Milestone-Proposal:TRON Intelligent House

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Docket #:2023-28

This proposal has been submitted for review.

To the proposer’s knowledge, is this achievement subject to litigation? No

Is the achievement you are proposing more than 25 years old? Yes

Is the achievement you are proposing within IEEE’s designated fields as defined by IEEE Bylaw I-104.11, namely: Engineering, Computer Sciences and Information Technology, Physical Sciences, Biological and Medical Sciences, Mathematics, Technical Communications, Education, Management, and Law and Policy. Yes

Did the achievement provide a meaningful benefit for humanity? Yes

Was it of at least regional importance? Yes

Has an IEEE Organizational Unit agreed to pay for the milestone plaque(s)? Yes

Has the IEEE Section(s) in which the plaque(s) will be located agreed to arrange the dedication ceremony? Yes

Has the IEEE Section in which the milestone is located agreed to take responsibility for the plaque after it is dedicated? Yes

Has the owner of the site agreed to have it designated as an IEEE Milestone? Yes

Year or range of years in which the achievement occurred:


Title of the proposed milestone:

The Pioneering TRON Intelligent House, 1989

Plaque citation summarizing the achievement and its significance:

The first TRON Intelligent House was based on the concept of a Highly Functionally Distributed System (HFDS) as proposed in 1987. Built in Tokyo in 1989 using about 1,000 networked computers to implement Internet of Things (IoT), its advanced human-machine interface (HMI) provided “ubiquitous computing” before that term was coined in 1991. Feedback by TRON’s residents helped mature HFDS design, showing how to live in an IoT environment.

200-250 word abstract describing the significance of the technical achievement being proposed, the person(s) involved, historical context, humanitarian and social impact, as well as any possible controversies the advocate might need to review.

TRON Intelligent House was built in Tokyo in 1989. It had about 1,000 computers, and many sensors and actuators in a 333 square meter space. It was built by a group called TRON Intelligent House Study Group, consisting of 18 member companies, which understood the concept of Highly Functionally Distributed System (HFDS), essentially today's IoT. HFDS proposed in the 1980s by Ken Sakamura, the leader of TRON Project, was the true pioneer of today's IoT vision. Computers were hidden as much as possible to create a people-friendly atmosphere. People lived in the house so that we could obtain valuable feedback about the computer-controlled living environment. There have been many off-the-shelf housing components developed later from the prototype created for the TRON Intelligent House. The TRON Intelligent House had an impact on smart house research and development in Japan and elsewhere. In its wake, newer TRON Intelligent House projects (v2 in Japan in 2004, v3 in Taipei in 2009) followed and so-called IoT campus building in Japan was built in 2017, and the latest smart house research goes on which inherits the knowledge of the first TRON Intelligent House and the later projects.

IEEE technical societies and technical councils within whose fields of interest the Milestone proposal resides.

In what IEEE section(s) does it reside?

Tokyo section

IEEE Organizational Unit(s) which have agreed to sponsor the Milestone:

IEEE Organizational Unit(s) paying for milestone plaque(s):

Unit: Tokyo Section
Senior Officer Name: Kiyoharu Aizawa

IEEE Organizational Unit(s) arranging the dedication ceremony:

Unit: Tokyo Section
Senior Officer Name: Kiyoharu Aizawa

IEEE section(s) monitoring the plaque(s):

IEEE Section: Tokyo section
IEEE Section Chair name: Kiyoharu Aizawa

Milestone proposer(s):

Proposer name: Chiaki Ishikawa
Proposer email: Proposer's email masked to public

Please note: your email address and contact information will be masked on the website for privacy reasons. Only IEEE History Center Staff will be able to view the email address.

Street address(es) and GPS coordinates in decimal form of the intended milestone plaque site(s):

The Daiwa Ubiquitous Computing Research Building, The University of Tokyo (Address: 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; GPS coordinates; N 35.7079711, E 139.7626922)

Describe briefly the intended site(s) of the milestone plaque(s). The intended site(s) must have a direct connection with the achievement (e.g. where developed, invented, tested, demonstrated, installed, or operated, etc.). A museum where a device or example of the technology is displayed, or the university where the inventor studied, are not, in themselves, sufficient connection for a milestone plaque.

Please give the address(es) of the plaque site(s) (GPS coordinates if you have them). Also please give the details of the mounting, i.e. on the outside of the building, in the ground floor entrance hall, on a plinth on the grounds, etc. If visitors to the plaque site will need to go through security, or make an appointment, please give the contact information visitors will need. It is a university campus building. It is where Prof. Ken Sakamura (Professor Emeritus, The University of Tokyo) who proposed and designed TRON Intelligent House completed in 1989 held his last office at the University of Tokyo. He held many meetings for TRON Intelligent House on the University of Tokyo Campus. back then.

Are the original buildings extant?

No. TRON Intelligent House was demolished after five and half years to make way for a high rise building.

Details of the plaque mounting:

The plaque will be displayed in the entrance hall of The Daiwa Ubiquitous Computing Research Building, The University of Tokyo.

How is the site protected/secured, and in what ways is it accessible to the public?

The plaque will be fixed on the wall of the entrance hall in the Daiwa Ubiquitous Computing Research Building, the University of Tokyo, which is accessible to the public with permission.

Who is the present owner of the site(s)?

Professor Noboru Koshizuka (The University of Tokyo).

What is the historical significance of the work (its technological, scientific, or social importance)? If personal names are included in citation, include justification here. (see section 6 of Milestone Guidelines)


This section explores the TRON Intelligent House, a pioneering experiment in smart home technology initiated in Tokyo in 1989. The house integrated about 1,000 computers and numerous sensors and actuators across 333 square meters, employing the concept of the Highly Functionally Distributed System (HFDS), a precursor to the Internet of Things (IoT). The home was a living laboratory where real people resided to provide feedback on a computer-controlled living environment. Multidisciplinary contributions from leading technology companies resulted in a seamless blend of technology and traditional Japanese architecture, with natural materials and a design focus on user comfort and interaction.

Key features of the house included motorized windows and ventilation systems responsive to weather sensors, computerized kitchen equipment, an intelligent storage system, and health-monitoring toilets, most of which were later commercialized and influenced today's smart homes. The house's computers including Sun Microsystems, and PCs running BTRON OS that showcased early graphical user interfaces pre-dating Windows 3.0. Additionally, an emphasis on Human-Machine Interface (HMI) standardization offered simplified operation despite the underlying complexity.

The TRON Intelligent House aimed to hide technology from view, stressing calm computing [CALM2024] environment where interactions with the house's systems were designed to be as natural and non-disruptive as possible. This philosophy extended to the use of natural building materials, the integration of green spaces within the living areas, and subtle, computer-controlled lighting, offering residents varying scenarios that complimented their activities and time of day.

Behind the scenes, sophisticated coordination among devices performed energy-saving tasks like opening windows to naturally regulate temperature, while security measures ensured personal safety and privacy. With details enriched by quotes from Sakamura's works and a few reports of the smart house activities from Popular Science, descriptions of the interdisciplinary cooperation among companies, and a YouTube video for visual context, the section offers an in-depth look at the TRON Intelligent House as an early embodiment of smart living and a testament to the potential of integrated, intelligent design in architecture.

The section concludes by tracing the legacy of the TRON Intelligent House through a series of follow-up projects, including TOYOTA PAPI, Taipei u-home, and ongoing research at TOYO University, reflecting a sustained evolution in smart home and building innovation. These developments underscore the project’s influence on smart house technologies, which continue to evolve and expand globally.

Historical significance of the TRON Intelligent House as a realization of the IoT

The TRON Intelligent House was built with the design philosophy based on the notion of Highly Functionally Distributed System (HFDS) in mind. [SAKA1987d][SAKA1988b][BRIT2024]

What is HFDS?

In the vision of HFDS, many objects in our surroundings are embedded with computers. They are called intelligent objects. They talk to a local network (and with outside if such connection is available), and to other intelligent objects to offer coordinated activities together. Intelligence can be in the Intelligent objects themselves or in the servers accessed via networks. Thus various functions become distributed in our surroundings, thus Highly Functionally Distributed System.
HFDS is essentially today's notion of the IoT. Please see the following figure.


  Figure of the Concept of HFDS from Sakamura, K.: The Objectives of TRON Project: Open-Architecture Computer Systems”, Proceedings of the Third TRON Project Symposium, Springer Verlag, pp. 3-16., 1987.

The notion of HFDS had been proposed in 1987 BEFORE the phrase "ubiquitous computing" coined by Marc Weiser became popular in the 1990s by his Scientific American article [WEIS1991]. Even before ubiquitous computing, the similar notion had been already stated using the word HFDS by Sakamura and was used in TRON Project, and it was behind the design philosophy of the TRON Intelligent House.

Similarity of HFDS and the IoT

The vision of HFDS is basically the Internet of Things today in that the Intelligent objects are things that are connected to the network, most likely to be the local wire full LAN, Wi-Fi, Bluetooth that connect other things together. In this sense, HFDS encompasses Machine-to-Machine (M2M) communication. It also places the humans as the recipients of the services and as occasional command issuing entities. So it encompasses the human-to-machine interaction, thus human-machine interface (HMI) is very important in HFDS scheme. This importance of HMI is discussed in as 'G.1 HMI enabling use by anyone' in "TRON Intelligent House gave valuable feedback to the design of HFDS", and "Importance of HMI for tangible objects not only for PC Desktop" section.

Important thing is that these intelligent objects do not exist alone, but they offer services when they work together: sensors, and actuators work together to perform actions. They executed the collaborative activities in the first TRON Intelligent House completed in 1989 as explained in the section "Coordinated IoT-like Services". It should be stressed that the TRON Intelligent House was built in 1989 BEFORE the concept of ubiquitous computing was widely disseminated in 1991.

Recognizing the importance of HFDS proposed in the 1980s, the achievement of the TRON Intelligent House and the on-going research since then, International Telecommunication Union (ITU) awarded Sakamura the prestigious ITU150 award along with other five members who have made great contributions to telecommunication industry and IT industry in general in 2015. The full citation of the ITU150 Award is given in [ITU2015]. Here is a partial excerpt from it:

 He has been the leader of TRON Project since 1984, and has designed the TRON open computer system architecture which will be useful for ubiquitous computing of the future. Today, the real-time operating systems based on the TRON specifications are used for engine control on automobiles, mobile phones, digital cameras, and many other appliances, and are believed to be the among most popular operating systems for embedded computers around world. The R&D results from TRON Project are useful for ubiquitous computing. 

Background History of HFDS

Before delving into the TRON Intelligent House, let us position the birth of HFDS in the historical context.

In 1985, when Sakamura published the book "Intelligent Cities: Science Fiction and Future Computers," (in Japanese 電脳都市: SFと未来コン ピュータ) [SAKA1985] (a second version was published in 1987 [SAKA1987g]), he envisioned implementing the first TRON Intelligent House, then TRON Intelligent Building, and finally TRON Intelligent City, the largest application of the HFDS environment, in order to realize a society with computers everywhere. The first target was the TRON Intelligent House, to be followed by the "TRON Intelligent Building".

In 1987, Sakamura presented his concept of the HFDS in an English paper [SAKA1987d]. He predicted that in the future global human society, microprocessors would be embedded in every part of daily life (a single light bulb, a single wall panel, etc.) and would interact with humans in some way. He presented a vision of the future in which these devices would not be controlled separately, but would behave cooperatively with each other talking over the network. TRON Project was defined as a project to prepare for the realization of this vision.

The things or tangible objects with computers embedded inside are called intelligent objects in HFDS terminology.

When an HFDS society is realized, and intelligent objects are installed in everywhere around us, a network system to control them will be necessary. In 1988, the "Macro TRON" paper [SAKA1988b] (quoted below) was published.
From Macro TRON paper:

  MTRON (Macro-TRON) is the network architecture for building the HFDS (Highly Functional Distributed System) in the TRON Project. Nodes with embedded microprocessors in an MTRON network are called intelligent objects The HFDS is designed to be scaled into a very large network consisting of vast numbers of such intelligent objects. The HFDS needs various forms of data and real-time communication services, which MTRON is designed to provide using a composite layered architecture approach. Applications in the HFDS include management of buildings. In order to handle the position-dependent processing of intelligent objects inside a building, MTRON is specifically designed to handle the concept of the physical position of a node. In order to communicate with the large number of nodes that will be connected to networks in the future, communication protocols are defined dynamically using TULS (Tron Universal Language System).

The idea of MTRON had been in the works even before that. [SAKA1987][SAKA1987h].

It was assumed that the existence of MTRON would create an open network (distributed computing) environment. In other words, it is the equivalent of a control environment for the entire system in a house, a building, a city, or even a society as a whole in today's IoT vision.

Development based on this concept was carried out in many fields. For example, the μITRON 3.0 specification[SAKA1998], a specification document for a real-time OS, states that the goal of TRON Project is to realize a "Computer Augmented Environment" in which "computer embedded devices are connected to a network and are allowed to actively affect their environment. The role of RTOS is positioned within this overall framework.

The design and implementation of the TRON Intelligent House need to be understood in this historical context.

Popularization of HFDS under different names - Computing Everywhere

The notion of HFDS was deemed a bit difficult to explain to the general public, In his enlightenment activities in the late 1980s and 1990s, Sakamura often called it "Computing Everywhere" (or "Computers Everywhere"). ([SAKA1993b], "Guest Editor's Introduction: Toward a World Filled with Computers" in IEEE Micro) It referred to the fact that computers will be in many things, i.e., intelligent objects will be everywhere in our living environment. After the term "ubiquitous computing", coined by Mark Weiser became popular ([WEIZ1991] Mark Weiser, The Computer for the 21st Century, Scientific American, September 1991) around 2000, he started to use the phrase. Furthermore, since around 2010, he began to use the word, the IoT, since the general population became familiar with the term and its concept, which is basically HFDS.

Readers who may try to read old papers may be confused by the different terms used at different times. But the original concept in TRON Project is traced to the HFDS concept from the 1980s.

Technological significance

The TRON Intelligent House was a true pioneer of today's smart houses.

It housed about 1,000 computers in a 333 square meter space and had many sensors and actuators. It was built with the HFDS concept. (We come back to this "House with the HFDS concept at the core" section.) Computers were hidden as much as possible to create a people-friendly atmosphere. People lived in the house so that we could obtain valuable feedback about the computer-controlled living environment.


Photo from [NORM1990] (Dennis Normile, From Japan: Intelligence with Classic Style, Popular Science Popular Science, September 1990)

English caption:

  The experimental house has motorized windows that automatically act
  in concert with external weather sensors and the ventilating

The first TRON Intelligent House was built by the group companies of TRON Intelligent House Study Group (tentative English translation) which was headed by its leader, Dr. Ken Sakamura, then an associate professor of the University of Tokyo, The members/companies are as follows (from the listing in [SAKA1990-a]).

  • Design by Ken Sakamura
  • Execution design, production, and construction / TRON Intelligent House Study Group
  • Construction / Nihon Homes
  • Intelligent Function Software / ATC
  • Control and Information Equipment / Takenaka Corporation, and Eiraku Electric
  • Kitchen Equipment / Sun Wave Industries (now LIXIL Corp.), and Tokyo Electric Power Co.
  • Sanitary Equipment / Toto Equipment (today's TOTO)
  • Air Conditioning Equipment / Taikisha, and Mitsubishi Electric Corporation
  • Lighting equipment / Yamagiwa
  • Storage equipment / Motoda Electronics Industry (元田電子工業)
  • Audio equipment / YAMAHA
  • Communication and Information Equipment / Nippon Telegraph and
  • Telephone, and Japan Airlines
  • Plant management equipment/Daiichi Engei Co., Ltd
  • Sash / Sankyo Alumi (then, now it is Sankyo Tateyama, Inc.)
  • Glass / Nippon Sheet Glass Co., Ltd
  • Roofing / Nippon Steel Nisshin Co., Ltd. (now merged into NIPPON STEEL CORPORATION and no longer exists.)
  • Household goods / Seibu Department Store (then. Now, it is Seibu Sogo Department Store.)

They were the leading companies of the respective technological fields. Having these members in the group which built the house was instrumental in bringing the new or improved technologies into the market later in the form of off-the-shelf products for construction industry to use in people's homes.

Japan Airlines, JAL, was listed in the Communication and Information Equipment section: it is because JAL offered BBS-like service to its customers and was interested in bringing graphical interface to the PC terminal client using BTRON OS (explained later).

The TRON Intelligent House needs to be viewed with its holistic approach of HFDS to build a computer-assisted living environment instead of looking at individual devices. [SAKA1987d][SAKA1988b]

Also, despite the plethora of computers, devices, sensors and actuators, the TRON Intelligent House posed a very simple user-friendly face to the residents. The uniform GUI based on the TRON guideline [SAKA1991, Human interface with computers in everyday life] and the default behavior deduced by the computer system made the operation very simple despite the complexity hidden behind the user interface (This is explained more in detail about HMI standardization in "Importance of HMI for tangible objects not only for PC Desktop" section.)

Let us explain the technological features of the TRON Intelligent House using some articles.

Here is a quote from Sakamura's article in April 1990 issue of IEEE MICRO [SAKA1990b] (Ken Sakamura, The TRON Intelligent House, IEEE MICRO, April 1990):

  Approximately 1,000 computers interact to support this house. The direct cost of building on this 300-square-meter lot was 1 billion yen (US$6.7 million), and the additional indirect costs reached 2 billion yen (US$13.4 million).

(Submitter's Note: There seems to have been a typo.: 300-square-meter ought to read 333-square-meter. See [SAKA1990a].)

Introduction to The House of the Future

The introduction of the first TRON Intelligent House written by Ken Sakamura for April 1990 issue of MICRO [SAKA1990b] is still current. Additionally, the magazine, Popular Science, published its September 1990 issue with the special theme of Smart House. [POPU1990] The issue covered the TRON Intelligent House in an article [NORM1990] written by an objective third party reporter who interviewed Sakamura and visited the house. So let us quote some paragraphs from the articles as a detailed introduction to the house.

Note: The readers of this Milestone application are also advised to watch the video of the TRON Intelligent House available on YouTube [YOUT-1].
This is an edited video created in the 2010 from a much longer video (30minutes or so) made circa 1995 while the TRON Intelligent House still existed.
Parts of the video are referenced again when each sub-component of the TRON Intelligent House is discussed later in this application document.

Sakamura begins [SAKA1990b]:

  The TRON Intelligent House is the experimental prototype of the future house, which incorporates the results of the TRON Project that proceeds under my leadership. The house reflects my idea of the house of the future. Many parts of the TRON House have sensors, computers, and actuators. These network-connected devices can work with each other in a cooperative manner. For example, if the controls of two subsystems seek conflicting objectives, an overall control instructs them to compromise.

Here, the coordinated behavior of network-connected devices is mentioned. This is a reference to the HFDS control. The computer architecture project called TRON Project is mentioned. Sakamura has been the leader of the project since its inception. [TRON2024][SAKA1989a]
TRON Intelligent House project was a sub-project of TRON Project. [TRON2024] (TRON Project is explained in detail in Appendix VIII.)

Sakamura continued in [SAKA1990b]

  I based my concept of the intelligent house on the idea of the "intelligent object" that uses computers to control its behavior. I designed the house, however, with an express purpose of not placing computers in visible places and using natural materials and natural surroundings to best advantage to create a pleasant environment. Computers help run the house to maintain comfortable living conditions only when problems arise.

The above paragraph refers to the HFDS and intelligent objects. It also refers to the architectural approach of the TRON Intelligent House. One of the characteristics was hiding computers from human eyes. This approach of so-called Calm Computing [CALM2024] is elaborated further in the "Hiding the computers and sensors to make the house natural" in "Features that set apart this from others" section.

In the later part of the article [SAKA1990b], Sakamura stated, as follows.:

  So, I stress here that the computerized appliances of the future must communicate with each other to offer good service to users.
  Why, then, don't today's appliance designers take this total approach?
  Generally, it is because designers know consumers will select many appliances from various manufacturers and will always purchase additional devices later on. As a result, the operation methods in appliances have no standard interface. With this background, no manufacturer will be able to take a system approach to appliance design unless supporting infrastructures such as standardization are available. The TRON Project aims at offering such infrastructure.

So the TRON Intelligent House was a testing ground for computer infrastructure of the future, as well as a testing ground of sensors and actuators of the era beyond the barriers of enterprises. (Basically, in today's parlance, the spirit of open API was taught to the engineers of member companies. It was an uphill battle.)

Human-machine interface standardization was attempted for the TRON Intelligent House. It is explained later in this Milestone application. (in "Importance of HMI for tangible objects not only for PC Desktop" section.)

Sakamura continued to explain in [SAKA1990b]:

  Let me explain the functions of the TRON House briefly. The objective of this pilot house is to allow designers to participate in many experimental approaches rather than offer a practical house immediately.
  The TRON House includes house wide networks and sensor, telephone, video, audio, and utility subsystem networks.  A central computer system placed in the basement, and called the house server, monitors and controls these networks and handles the database.
  The sensor network keeps track of temperature, humidity, wind direction, air pressure, carbon dioxide content, rain, interior air circulation, and people's positions. The multifunction telephone system contains a digital PBX that controls the telephone, intercom, and computer communication. A video system broadcasts the images taken by internal cameras of the entrance and living rooms, the data from each subsystem, and television data received from outside. An audio system feeds sounds to the listeners from internal sources, external radio sources, and combinations of these.

Despite experimental feature mentioned in the first paragraph, or rather because of it, the house was lived in to obtain valuable feedback for the future research. (More in section, "People lived in the house for prolonged time.)

The second paragraph in the above quote refers to the home server in the basement. This was a Sun Microsystems server. Ordinary desktop PC of the time did not have the horsepower to handle all the ambitious services of the TRON Intelligent House. However, the house used some PCs that ran BTRON OS on Intel 80286 CPU to handle graphical user interface and some audio-visual peripherals (explained later).

Photo: Courtesy of Ken Sakamura

  Photo caption: The upper half of the photo shows the wiring in the
  first TRON Intelligent House. There were serial cables (RS232C,
  RS482, RS485, etc.) and co-axial cables.  The lower half of the
  photo shows the home server, a Sun Microsystems machine in the left
  corner near the wall. (The violet one).
  The computer below the desk ran BTRON OS (a stylized 'B' is visible in
  the logo in the front.).  There were other computers to control devices.
  Near left is the rack of AV signal distribution devices.

The third paragraph above refers to the sensor network and sensors. These are important topics even today in the age of the IoT. Basically, the TRON Intelligent House created an IoT network in a large scale that had not been attempted before within the area of 333 square meters. (This is elaborated more in the section "Protocols of internal bus inside the houses and buildings".)

It also refers to a multifunction telephone system. Please note that smartphone that connects to the Internet was a dream in the eyes of some visionaries back in 1989 and the preceding years that led to the construction and completion of the house. There was no commercially available Internet connection to begin with. So telephone PBX played an important role to connect the house to external entities back then. We could control the house functions from a payphone using dial tone, for example.

The second and third paragraphs refer to the audio visual data. Audio visual data handling was not easy on computers back in the late 1980s. Aside from Alto of Xerox PARC [ALTO] and Apple Macintosh [MaciII], graphics handling on general PCs was very poor and often black/white only. Color graphics on Macintosh appeared first with Macintosh II that was first sold in March 1986. Windows 3.0 appeared later on May 22, 1990. [WIND30]

Sakamura continued in [SAKA1990b]:

  A system that consists of sensors, automatic windows, four heater/cooler systems, a water spray machine on the roof, and fans to draw in the external air controls the air conditioning. Computers control the lighting so that it allows different lighting scenarios for each room. This system also controls the closing and opening of curtains. The kitchen has a computer cooking guide that uses the multimedia functionality of the BTRON computer (another TRON Project feature). This computer controls the cooking utensils and even dispenses the right amount of seasonings as needed.
  Your health can be monitored by a computerized toilet facility that performs a urinalysis automatically. An automated storage system can place unused objects into containers and move them to the basement warehouse. An automated garden system grows plants using hydroponic techniques, and water-level sensors control the water supply. The security system is based on external infrared sensors and internal heat sensors.
  A computerized house is useless if the people living there cannot make use of it easily. So, operation of all the switches in the house is designed according to the TRON Design Guideline. Today, we find that the standardization of operation on computer workstations attracts much attention. What we have done is apply the same idea to the switches in our surroundings. Inhabitants in the house can control operations with standardized switches, intelligent remote controls that have receivers in every room, or BTRON computers.
  Over the course of three years, we plan to let people live in the TRON House so that we can monitor the data and analyze the cooperative behavior of intelligent objects. We will also try to gather valuable experience from simulated computer breakdowns, fires, and intruders.
  April 1990

Please recall that all the services mentioned above were designed and executed in the HFDS framework.

Human Machine Interface (HMI) issue needs to be explained first. The second to the last paragraph in the above quote refers to the TRON Design Guideline ([SAKA1991]). This was later published as TRON Human-Machine Interface Guideline ([SAKA1996]). Eventually the contribution was standardized and published as a guideline document by international standardization organization IEC.: "Guidelines for the user interface in multimedia equipment for general purpose use". It was published as Technical Report [IEC2001]. You can see the switches in the first TRON Intelligent House all conform to the guideline as much as possible. They look similar from afar.


Photo from [SAKA1990a] Japanese caption:

  The switch on the master bedroom. Switches for illumination, air conditioner and
  motorized curtain and the generic "good morning" and "good night"
  switch to control many objects at once are there.

There is an overview about the switches that follow the design guideline in the video, [YOUT-1]:

By the time the TRON Intelligent House construction was started, TRON Project had produced BTRON OS for desktop computers. (See [SAKA1987c][SAKA1987e], for example.) Application programs on that OS could handle graphics data in a windowing environment. It could control audio visual data on the peripheral devices such as VCR and laser disks. There are some video clips that show how the BTRON screen looked like on YouTube. An example is as follows.: (The video is from the TV original series, "Age of Computers", aired in 1987. [NHK1987])
This was before Windows 3.0 appeared. The TRON Intelligent House used computers that ran BTRON OS to handle video such as the one used in the kitchen (the kitchen is explained later in more detail.)


BTRON Desktop circa 1987

   Photo caption: In this picture captured from the YouTube video, the
   left window shows a live video stream from a connected VCR (or laser
   disc). The image could be imposed on figures like the circular clock
   face on the right. The operation is shown in the video).

The second paragraph above refers to the following services:
- health monitoring toilet
toilet on the second floor (medical check). The short explanation is given in the video, [YOUT-1]:

SAKA1990a-toilet.JPG Photo of the toilet from [SAKA1990a]
Japanese caption reads:

  Health monitoring toilet. Urinalysis and blood pressure
  measurement is done. On the left is the urinal with automatic door.

- computerized storage system
Photo from [SAKA1990a], Japanese caption reads:

  The entrance opening of "computer archive" (It was called with this
  name back then, it seems.)  Many household things were put into
  containers stored underground.  They can be retrieved using the
  image monitor and operation panel.

There is also a short introduction in the video, [YOUT-1]:

- garden system

SAKA1990a-garden-system.JPG Photo from [SAKA1990a]

There is also a short introduction in the video, [YOUT-1]:
The video explains how to grow plants in the TRON Intelligent House.

- Security system

This feature was an important IoT-like service for LIVING in the house. People lived in the house for real so we could obtain valuable feedback on the devices and software. The house was NOT a simple experiment for novel devices. We could learn how easy it was for the residents to obtain the service of computer-controlled devices.

The third paragraph refers to the feedback collected after people lived in the house for a while. This really distinguishes this house from other smart houses. This is explained in more detail in the section, "Features that set apart this from others".

House with the HFDS concept at the core: Not a random collection of devices

The holistic design approach and implementation of the TRON Intelligent House based on HFDS distinguish it from some other projects where only a few devices were tried, or where the overall design framework was missing.

Context awareness: The TRON Intelligent House was aware of the surrounding. It knew how clear the sky was, whether it was raining outside, outside/indoor temperature, and humidity. It used the information to control itself. It also knew the presence of human residents.

The sensors and devices mentioned in the introduction of Sakamura's Japanese article [SAKA1990a] and in the following explanations, and computers installed in the TRON Intelligent House were not just a random collection of novel devices. They were connected via network and their behavior were coordinated under the notion of HFDS. These "novel devices" were not just placed randomly.

Such grand vision seemed to be missing in other attempts at creating smart houses at the time. This is discussed more in "Features that set this apart from others".

Many imagined devices were missing and needed to be built

The devices taken for granted for today's smart houses were non-existent then. Also, futuristic services of the smart houses were conceived, and necessary devices were developed.

Many such devices (mostly sensors and actuators) were commercialized afterward.

Let us explain how they were used in the TRON Intelligent House in the following and the coordinated behaviors under the control of the "home server" that tried to control the house in a holistic manner based on HFDS.

Here is a table of some devices that were created and installed in the TRON Intelligent House in 1989 aside from the ones already explained.
(Submtter's note: Table tags do not work; thus I am attaching a table in JPEG format.) TRON-Intelligent-House-devices-v3.jpg
The last entry of the table needs explanation. Many legacy devices were turned into IoT-enabled devices by attaching small computer boards that can talk to intra-house network, and were installed in the house. E.g., motorized window screen, window opener, audio-visual equipment (few people envisioned the network-control of these devices yet), etc.

Details of the devices in the table are explained in Appendix X.

Coordinated IoT-like Services

There were many coordinated behaviors of IoT like services. Their implementation and testing were carried out by the member companies during the TRON Intelligent House project over a few years and no complete listing exists now.

Let us enumerate a few of them recorded in published documents here.

E.g.: Opening windows to let wind flow into the house when it was fine outside, and the temperature was just about right, (both checked by sensors).

The windows were opened by actuators automatically to let the wind in. This was part of the energy saving feature and compliments the air conditioning system installed in the house. This was observed in detail by the third party Popular Science reporter and was described on page 60 of [NORM1990]. Note that lighting is intricately linked with cooling.:

     The integration of the various systems is refined to the
  extreme. For example, people sitting under bright lights gain
  radiant heat even though the lighting does little to warm the
  air. Therefore, lighting level is one of the considerations in
  controlling the heating, ventilation and air conditioning systems.
     There are actually three HVAC systems. Forced-air heating and
  colling are delivered throughout the house. In addition there
  are two radiant systems on the first floor. For heating, hot water
  is piped beneath the floor, for cooling, cold water is piped above
  the ceiling. The intent is to eliminate cold floors and hot
  Ongoing "living" experiment
     At some point with the next year, a family will move into the
  house and live with the ongoing experiments.
     *Thermographic devices, which can tell how many people are in a
  room and can determine their body temperatures by the infrared
  radiation emitted will feed data to the HVAC control systems. This
  information helps the system determine the cooling or heating load
     *Data from indoor air-velocity and temperature sensors will be
  used to determine HVAC fan speeds. The goal: to eliminate hot and
  cold spots within a room.
     *Digital phones will control functions from the house and
     *Microprocessors in the roof-mounted weather station (which
  includes wind-direction, wind-velocity, air-pressure, rain, and
  brightness sensors) will actuate motors to open and close windows.

Interestingly, thermographic devices were not mentioned explicitly in [SAKA1990a][SAKA1990b][SAKA1991b]. But it is noted in [NORM1990] as above. There were many experiments, 100+, during the project, so nobody at one time was on top of EVERY experiment that went on.

E.g.: Music sound volume from the speakers was turned down when the phone rang.

E.g.: The house activated and controlled the air conditioners only when there were human inhabitants inside the rooms.

E.g.: weather sensor and window actuator

When it rained outside, the windows were closed automatically. Again, the sensor and actuators were coordinated by a control program.

E.g.: Turning on foot light when someone woke up during night

When someone woke up and got out of bed in the middle of the night, the human sensor recognized it and automatically turned on the light. Lighting including general overview and foot light is explained briefly in the video, [YOUT-1]:
In [SAKA1991b], Sakamura mentioned a few more examples of coordinated behavior obviously implemented in the first year of experience/experiments in the TRON Intelligent House. Quote:

  * Information from the security system can be shared with
  the lighting system, so that lights are turned on automatically
  when a room is entered, and turned off when the room
  is vacated.
  * Likewise, daylight information is useful not
  only to the lighting system but to the air conditioning system
  as well. The amount of heat emitted by electrical appliances
  is also something the air conditioning system should
  * While we are at it, music lovers would appreciate an
  air conditioning system that would compromise its cooling
  or heating objectives during soft passages in music by operating
  more silently.
  * Besides refined services like those I have mentioned,
  another advantage of HFDS is the greater possibility of
  cross-checking and backup, for safer overall system operation.
  HFDS realization is the ultimate goal of the TRON Project.

Since the project was privately funded, no comprehensive report of the experimentation done by the member companies exists. But many were reflected in the later development by the member companies such as the acoustic field creation by YAMAHA. (These are discussed in Appendix X.)

We already realize that the third party reporter wrote a coordinated behavior which was missing from Sakamura's writing. The impact on the living residents (or visitors) was quite likely to be different from the original intent of the designer. So having people live in the house to obtain feedback is an important step for smart house design. The TRON Intelligent House followed this step.

Architectural significance from the viewpoint of building a house

The TRON Intelligent House was user/resident friendly.

The house and the computer system were designed by Sakamura.

The beneficial uses of computers for house residents were investigated and were implemented. But there were architectural design issues.

Computers ought to be invisible

When the TRON Intelligent House was designed, it was decreed by Sakamura as the main architect that computers and sensors were hidden as much as possible. They were the servants and services shall be provided naturally as much as without human intervention. Sensors were placed as discreetly as possible. This aspect is discussed in more detail in "Hiding the computers and sensors to make the house natural" section.

The house used natural material according to Japanese tradition such as wood and stones. The design was simple and modern.

There was a large open space to facilitate communication among family members, and semi-open spaces in the center and indoor garden. (Glass separators that became transparent helped to create spacious atmosphere.) Indoor plants grew on artificial soil, watering was computer controlled. This gives a very natural feeling to the house. This aspect of the house is explained briefly in the video, [YOUT-1]:
This type of automatic watering system has been commercialized. For example, in u-Home, a Taiwanese TRON Intelligent House built in 2009 (explained later and in Appendix II) used a similar commercial off-the-shelf system from a different company.

Lighting sources were hidden and controlled finely

The lighting was adjustable under computer-control. They were not simply turned on/off. They were controlled to offer particular preset lighting environment such as bright setting for party time, and dim setting for private moment. This was to give natural comfortable feeling to the house.


Photo from [SAKA1990a] Japanese caption:

  A view of the kitchen and the semi-open space from the dining room.
  The lighting source and power source are all controlled by
  computers. The residents choose the basic scenario setting and then
  the final lighting tuning is done based on the season of the year,
  the hour of the day, etc. The photo is the supper scene lighting.

Lighting including general overview is explained in the video, [YOUT-1]:
Such adjustable lighting has been commercialized and has become very common now.

Many prototype devices tried at the TRON Intelligent House were commercialized as explained above by the members of the Study Group and other companies that followed.

Social Significance

The TRON Intelligent House was one of the earliest smart house projects in the world in which people really lived for a prolonged time to test various features to obtain the feedback for future smart houses.

There were impacts on the society before and after the project.

Bringing the vision of HFDS (i.e., the IoT) to the masses

Before the TRON Intelligent House project, it was necessary to appeal to various industries that create components for buildings and construction companies that the future house represented by the yet-to-be-built TRON Intelligent House is possible.

Aside from writing academic papers, Sakamura wrote many non-academic magazine articles. Enlightening books that "market" the future vision of computers envisioned in TRON Project, i.e., HFDS, had been written and read widely. [SAKA1982, How to cope with computers: the latest technology explained to non-techies], [SAKA1987g, New Version: Intelligent City], [SAKA1987i, Making of TRON], [SAKA1988c, Overview of TRON Project] to mention just a few. There are more. The whole list is given in [1994c].

Sakamura also appeared in many educational/nonfiction TV programs to enlighten the general population. [For example, he appears around 04:20 in the following video: コンピュータの時代、 「TRON の誕生」 The age of computers, "TRON Project is born." in Japanese,] These books and TV programs had effect on the society in general including construction industries and beyond. This was one reason many companies joined the TRON Intelligent House Study Group in 1985 when Sakamura initiated the project for the "House of the Future" in the first place.

Ten thousand visitors experienced the TRON Intelligent House

During the TRON Intelligent House was in existence (it was removed after five and half years due to the high cost property tax), it attracted media attention. During the project, approximately 10,000 visitors looked at the inside and outside of the TRON Intelligent House. The Dutch prince and the Minister of Construction of Sweden were among them. BBC, CNN and other overseas broadcasting corporations, newspapers, magazines sent reporters to cover the TRON Intelligent House and thus it was covered very well. Popular Science was among them. Unfortunately, because this was before the commercially available Internet age, few searchable articles remain. [TRON1994]

[WATA1990] is an interesting article in LA Times with negative and positive comments. It also mentions the USTR issue that is mentioned in the "Obstacle to be overcome" section.

BBC has archived a TV news aired in 1990 in on YouTube in which the TRON Intelligent House is covered for a couple of minutes. [BBC1990] ( You can see the kitchen monitor screen and a BTRON OS running in the house in the very good quality video. The PC in the video had a JAL logo because JAL demonstrated an online reservation system that uses the advanced graphics on the BTRON OS there.
Note: BBC news uses the term, TRON, in a very sloppy manner. This application document refers to TRON Project, and desktop OS developed in the TRON Project as BTRON OS. However, BBC news refers to all these and other technologies developed in the project using the term, TRON, in a very generic manner. Please do not get confused.

Popular Science recognized the novel approach of the TRON Intelligent House and its impact and gave it "The Best of What's New, Home Technology award" in 1990. [POPU1990b]

After TRON Intelligent House was removed, it spawned various similar projects later, executed in the grand framework of TRON Project, some realized, some on blueprint only due to the worsening of the Japanese economy later.

As noted earlier, many technologies developed for the TRON Intelligent House were commercialized and sold. They are available in the market.: YAMAHA's acoustic field creation system, TOTO'S washlet toilet, etc. (Washlet had been in the market already, but the sales took off in the 1990s. The wide publicity of the TRON Intelligent House in Japanese media, TV, magazines, newspaper, undoubtedly added to its sales later.) Many members of the TRON Intelligent House Study Group were specialized companies that created building components including hardware and software. Having them as part of the study group was essential for future deployment of newly devised devices and concepts.

Impact on the later evolution of smart house/building/city projects

In the long running TRON Project, the first TRON Intelligent House in 1989 spawned follow-up projects. These were triggered by the encouraging feedback from the first TRON Intelligent House. This Milestone application lists just a few to explain the evolution of the technology and impact in the years after 1989. The legacy of the TRON Intelligent House still lives on.


TOYOTA smart House PAPI was built in 2004. This house pursued energy-efficiency and the support for the aged. The house was called "the House of Sustainability". [A+U2005] It also appears in the video [YOUT-2]:

It incorporated many lessons from the first TRON Intelligent House and incorporated many new technologies at the same time.

Detailed explanation of TOYOTA PAPI is given in Appendix I.

There has been a healthy build-evaluate-improve feedback cycle in the history of the TRON Intelligent House project.

Smart Building project that followed

In the grand scheme of HFDS as explained in "Background history of HFDS", the smart house project naturally led to smart building and smart city project later.

TRON Intelligent Building Study Group (tentative translation) was formed in 1985 with 11 companies. [SAKA1991][TRON1994c]

The detailed explanation of the Smart Building project is given in Appendix III TRON Intelligent Building.

Unfortunately, at that time, nothing came out of the study group due to the downturn of Japanese economy later in the 1990s.

Smart City Project that followed

TRON Intelligent City project as an application subproject of TRON Project is explained in [SAKA1991b] and [TRON1994c]. This subproject was started in May 1989 while the first TRON Intelligent House completed in December 1989 was still under construction.

The detailed explanation of TRON Intelligent City project including a web page description is given in Appendix IV.

A modern IoT building: INIAD HUB-1 building at Toyo University 2017

INIAD HUB-1 is a building on the campus of Faculty of Information Networking for Innovation And Design (INIAD), Toyo University in Tokyo. Sakamura is the dean of the faculty until the end of March 2024. It was completed in April 2017. It is based on the concept of the IoT fully. This is based on the philosophy of TRON Project, HFDS. The building itself is the testbed for the IoT for research and education. [INIA2024]

Detailed explanation of INIAD HUB-1 is given in Appendix VI.

On-going Smart House project: Open Smart UR Study Group 2019

The heritage of TRON Intelligent House is still carried on in 2024. Sakamura as the dean of Faculty of Information Networking And Design (INIAD), Toyo University has collaborated with a large Japanese housing agency called Urban Renaissance Agency to start the study of smart homes for the 2030s since 2019. The joint collaboration already has built a demonstration room in Tokyo. [UROP2024]

This obviously is based on the tradition of the first TRON Intelligent House and subsequent ones (TOYOTA PAPI and Taipei u-home) and also the IoT-enabled INIAD HUB-1 campus building (explained previously).

In this manner, there has been an on-going research and development in Japan since the first TRON Intelligent House. Overseas development is explained in the next section.

Regional Impact outside Japan: Taipei u-home 2009

This topic does not follow the advancing timeline, but the date is back in 2009. It is generally accepted that the first TRON Intelligent House was the first smart house in Japan.[WIKI電脳] [NIKK2020], [NEWS2019], and [MONO1996] are examples of news pieces and blog pages that mention the TRON Intelligent House as the first house based on the IoT concept, namely HFDS.

The prolific writing of Sakamura disseminated the concept of TRON Project and HFDS, and the TRON Intelligent House had a huge impact on the Japanese IT and construction industry.

Triggered by the popularity of first TRON Intelligent House and then TOYOTA PAPI, the interest in TRON Intelligent House grew much in Japan. This was also true in other Asian countries, too.

Taipei u-home

Taipei u-home was completed in 2009, in Taipei. Built by Taiwan Land Development Corporation (TLDC), now called Taikai Group, it was promoted as the smart house of the future. Taipei u-home was a commercial demonstration of smart house based on the TRON Intelligent House Technology and design philosophy.

Construction of Taipei u-home shows the geographical expansion of the influence of the TRON Intelligent House project outside Japan that can be traced to the first TRON Intelligent House.

An overview of u-home is available as a short video on YouTube, [YOUT-3]:

Details of TAIPEI u-home is Appendix II.

Technology Transfer/Enlightening the public in Taiwan

Preceding and after the construction of Taipei u-home, Sakamura was instrumental in introducing the notion of smart house and smart city to Taiwan. This is a geographical expansion of the concept of TRON Intelligent House and HFDS outside Japan.

For TLDC, Sakamura talked in the city of Hualien (花蓮) on TRON Project and smart house/building/city development as part of enlightening the general population as well as construction companies in Taiwan. A few of the talks are available at Facebook account of TLDC (Taiwan Land Development, 台灣土地開發), For example, see its post on 2017 12/20.

In 2018, TLDC changed a new name of Taikai Group (台開集團). [CRYS2018] ("TLDC rebrands to reflect diversifications", Taipei Times). The newspaper article reported the new and expanded activity of the company and said "Taikai Group has also inked a cooperation pact with Japanese information science professor Ken Sakamura to turn Hualien into a smart city, making it more friendly for foreign visitors.", thus showing Taikai Group was seeking guidance from the original TRON Intelligent House project leader, Sakamura, to pursue it smart city project in Hualien.

What obstacles (technical, political, geographic) needed to be overcome?

Obstacles to overcome

This section delves into the obstacles encountered during the development of the TRON Intelligent House, focusing on technical, political, and geographical challenges. Key technical difficulties included creating new devices from scratch, given the absence of commercially available smart house technologies at the time, along with a lack of internet connectivity and standard communication protocols. Consequently, the project relied on extensive cable networks within the house and invented the TRON Application Databus (TAD) for device communication.

Political challenges were significant, most notably the incorrect classification of the BTRON operating system as a non-tariff barrier by the United States Trade Representative (USTR). This misclassification had a detrimental impact on the wide adoption of BTRON OS-based technologies in consumer electronics outside Japan, as companies feared possible repercussions on the U.S. market. Although the USTR eventually removed BTRON OS from the non-tariff barrier list, the damage to its adoption had already been done.

Geographically, land prices in Tokyo influenced certain design decisions, like the innovative intelligent storage system to efficiently use underground space. Despite political setbacks, the concepts and technologies developed through the TRON Intelligent House were successfully implemented in subsequent projects in Taiwan, demonstrating the project's ability to transcend geographical boundaries and influence smart building practices in Asia.

In summary, the TRON Intelligent House project was pioneering in integrating a holistic approach to smart home design, but it faced substantial obstacles that ranged from developing new technologies to navigating international trade misunderstandings. The legacy of the project is evident in its influence on later smart home and building developments in Asia and beyond.

Technical Obstacles

There were many technical obstacles to solve back in 1989.

New sensor/actuator devices had to be created.

Commercially available off the shelf devices for today's smart houses were non-existent then. Existing devices were not meant for external control by a device from different manufacturers. So they had to be either made from scratch or existing models for very special target fields (military, etc.) had to be modified heavily for commercial housing.

A portion of such devices are explained in Appendix X.

No Internet for external communication

Connecting with external sites and objects was rather difficult since there was NO INTERNET connection for commercial users in 1989. The bandwidth available for external connection at affordable price via telephone or dedicated line made it impossible to have high bandwidth communication which is possible today. No video streaming with external sources/destinations, for example.

Still, we could control some functions of the house by dial tone from outside payphones. Advanced encryption was used when the resident's medical data collected from the intelligent toilet was sent. Privacy and security were already paid due attention then.

All serial cable connection without Wi-Fi or Bluetooth

Wi-Fi and Bluetooth appeared in later years and were not available at the time of the first TRON Intelligent House. Connecting all the sensors and actuators with RS232C, RS482, RS485, etc. and other wire full technology including coaxial cable in the house was cumbersome and tedious. Wires stored in the house ran a dozen kilometers or so in total. Popular Science editor-in-chief stated as follows. [ABAT1990]: (Note that the photo of TRON Intelligent House was on the cover of the September 1990 issue of the Popular Science magazine in which this comment appeared.)

    By the numbers, the houses that comprise this month's cover
    report are staggering: Some 60 miles of wiring in one. A
    strategic array of 33 televisions and monitors in another. Price
    tags of $6 million and $7 million. Research and development
    expenditures upward of $30 million for one project alone.

Available devices often used proprietary ad-hoc protocols and there were no agreed upon data format for many environmental values. The home server in the basement had to understand them all.

To counter the lack of existing communication protocol for real-time data exchange, some researchers in TRON Project proposed a data bus for such data communication. [SAKA1987f][SAKA1988]. TRON Intelligent House used so called TRON Application Databus (TAD), a standard data exchange format for passing various data among devices at the level of central home server. TAD is explained in [SAKA1989b].

There is an additional discussion about the intra-house network in "Protocols of internal bus inside the houses and buildings" section.

Political obstacles to overcome

One reason the house may not have been known widely outside Japan and outside Asia was the following unfortunate incident.

The office of United States Trade Representative (USTR) of the US government listed the BTRON OS which was used inside the TRON Intelligent House widely as non-tariff barrier which made it difficult for overseas companies to enter the Japanese market. This happened in April 1989. [WATA1990]

This listing by USTR was patently incorrect because IBM and Unisys, both American companies, had already been working with their Japanese branch and Japanese partners to build PCs that ran BTRON OS and had interesting peripherals for audio visual education purposes.

Fearing a reprisal in the form of heavy import tax in the US market, Japanese home electronics companies which were expected to take up the technologies developed using BTRON OS PCs as controller in the TRON Intelligent House all stepped aside and stayed away from further development.

One year later, the US government removed BTRON OS from its non-tariff barrier list.: They admitted BTRON OS was not a non-tariff barrier after all. The US Commerce Department was tracking TRON Project at the time. (The proceedings of the 1991TRON Project Symposium only is in their database, while no earlier or later proceedings seem to be in their library. So obviously it was monitored for the trade friction issue for about a year. See, for example, )

But the damage had already been done by that time. The expected wide adoption in the Japanese home electronics industry did not happen. ([SYDN2003] - Japanese software guru doesn't envy Gates's riches, The Sydney Morning Herald)

This development was a great disappointment to TRON Project and BTRON OS developers. However, building component companies, mostly doing business in Japan, did take up the technology and produced many building components afterward based on what they learned from the TRON Intelligent House.

Geographical obstacles

It could be argued that the high land price in Tokyo prompted the creation of "Intelligent Storage System" which made it possible to use underground space for storage with easy retrieval mechanism. But this system should be very useful for single independent house everywhere.

The high property tax due to the high land cost led to the early demise of the TRON Intelligent House. After five and half years, a project member company who owned the land where the house was built could not justify paying the high property tax for foreseeable future anymore. So the project reluctantly agreed to demolish the house and let the member company develop a profitable high rise building there.

Taiwan u-home was built in 2009 and smart buildings were built in Hualian (花蓮) in 2011 using the technological elements developed from the heritage of the TRON Intelligent House. So in that sense, the barrier to disseminate the concept of HFDS and TRON Intelligent House technology outside Japan was low except for the political obstacle mentioned in the previous section.

The Intelligent Storage system that used underground storage space has not caught up in a big manner due partly to Japan's very humid climate. Until the early 2000s, Japanese houses did not try to use the underground space due to the water-rich soil in many parts of Japanese cities. But the trend has changed, and a simplified storage system is now marketed commercially by a company in Japan. In a drier climate of North America and Europe, the system should find useful application.

What features set this work apart from similar achievements?

Features that set apart this from others

This section illustrates the unique features of the TRON Intelligent House that distinguished it from other smart house projects of the late 1980s and early 1990s. At the heart of its design was the Highly Functionally Distributed System (HFDS), a forerunner to the modern concept of the Internet of Things (IoT). This house was part of a larger vision by Sakamura, including "TRON Intelligent Building" and "TRON Intelligent City," which envisioned a society enveloped in "computing everywhere."

The TRON Intelligent House was a live-in laboratory, a significant departure from other projects at the time, which allowed real-time collection of feedback to refine the HFDS framework. This feedback influenced the development of human-machine interfaces (HMI), ensuring that the technology was accessible to all users, including children, the elderly, and people with disabilities. Physical elements such as switches adhered to the TRON HMI guidelines, merging standardization in physical controls with virtual interfaces on BTRON OS computers.

Challenges in home automation and bus protocols such as CEBus and D2B, which primarily catered to AV equipment, did not meet the needs of a fully integrated intelligent environment; they lacked the holistic approach of HFDS. In contrast, the TRON Intelligent House overcame these limitations by developing a network that connected AV equipment, sensors, actuators, and employing a comprehensive communication system understood by a central home server. The TRON Application Databus (TAD) was part of this, highlighting the project's forward-thinking approach to data format standardization and device coordination decades before widespread adoption of similar concepts.

Lastly, the TRON Intelligent House's internal communication employed both existing technologies and those developed specifically for the project. The μBTRON Bus, a lightweight token ring bus created to handle musical data transfer, exemplifies the innovative spirit of the project. This approach extended to video and audio data handling, which was not based on universal standards but rather on ad-hoc solutions tailored to the House's system. The chapter showcases how the TRON Intelligent House not only executed the vision of HFDS but also contributed significantly to the basic research of the HFDS concept, influencing future developments in smart home technology.

The notion of HFDS was a key difference

The computers and sensors in the TRON Intelligent House were not a random collection of devices. They were assembled under the idea of HFDS. They were connected to the network, and they acted in a cooperative manner.

This is a key differentiating factor of the TRON Intelligent House.

The TRON Intelligent House is part of HFDS

TRON Intelligent House was a logical first step of the realization of HFDS, and was studied by a group that was formed in 1985. It is not an idea that came out of nowhere. It was implemented by 18 members who contributed the financial burden, land, workforce, etc. in 1989.

The history of these development were explained in [SAKA1991b].

The collection of environmental information to become aware of the surrounding context (context awareness) and the action based on the information were the basic principle of control done in the house.

Other similar activities did not have such a grand guiding scheme

It is not entirely clear whether other similar smart house projects of the same period were conducted under such a general guiding principle. Generally speaking, it seemed novel devices were tested without any coordinated behavior of devices.

The two smart house projects that were prominent in the USA and in Europe in the same time frame were covered in Popular Science September 1990 issue [POPU1990] which was published after the completion of the TRON Intelligent House. They are mentioned for comparison purposes in this IEEE MILESTONE application.

Many projects could not match the scale and budget of the TRON Intelligent House project which was completely financed by private enterprises. The scope of the project to include the real living in prototype houses was not easy to match. Also the vision of the IoT was missing from other experiments until years later. These points are clearly demonstrated by the observation of Popular Science writers.

For example, such grand vision like HFDS seemed to be missing in American Smart House initiative in the same time frame according to [GILM19990], an editorial of September 1990 issue of Popular Science on p.55 and 56.
It says, on p. 56, CEB-style home automation assumes that most of the intelligence will be in the devices that plug into the system. Smart House puts more smarts in the system.
And, on p. 57, it tells the readers CEB-style house would begin construction in April 1991, though the central controller and smart outlets won’t be ready till fall.

So although the American smart house covered by Popular Science then was supposed to supply some intelligence, the software and such was not available UNTIL the construction was to begin in late 1991.

This is a stark contrast to TRON Intelligent House Study Group’s approach. The group had been formed in 1985 already and the group had discussed the ideas and deployment of HFDS, and member companies had developed and produced components to be used in the TRON Intelligent House. So the software was already operating. The TRON Intelligent House was made open to public in April 1990. About 10,000 people visited the house in total. Then it was lived in for real to obtain feedback from the residents.

TRON Intelligent House gave valuable feedback to the design of HFDS

[SAKA1991b] explains the significance of activities of TRON Intelligent House and other application subprojects of TRON Project as follows. Quote from [SAKA1991b]

  The application projects play an essential role in achieving
  the ultimate goal of the TRON Project, which is to realize
  highly functionally distributed systems, or HFDS. In
  the HFDS concept, as more and more objects in our living
  environment are given microchip intelligence, their functioning
  can be made much more effective by networking
  them in loose alliances that will allow them to coordinate
  their activities. The TRON application projects are exploring
  HFDS possibilities through actual implementations, and
  are introduced here from this standpoint.

Thus application projects such as TRON Intelligent House project was executed to realize the vision of HFDS, and at the same it was expected to give valuable feedback to the design of basic specification of HFDS and other basic research projects (including TRON RTOS family, another IEEE Milestone). In this sense, the application projects were very important. Basic research subprojects and application subprojects were both wheels of TRON Project.

When the TRON Intelligent House was designed the following three major goals were set as objectives.

  • G.1 - HMI enabling use by anyone
  • G.2 - Establishing mechanisms for activity coordination (cooperative action) among intelligent objects
  • G.3 - Establishing programmable interface techniques

The last one is what we would call today, open API reachable via network. [SAKA1990c]

Importance of HMI for tangible objects not only for PC Desktop

HMI is very important in HFDS due to the following reason. TRON Project regarded the HFDS would expand the scope of users to include ORDINARY people because computers would be part of everyday life.: Children, elderly, and people with physical disabilities would interact with computer systems, like it or not. The Effect of computers on society as a whole would be significant.

So, how to make computer accessible to the new user base would be very important. This led to the human-machine interface (HMI) research.

The requirement was that the computers embedded in intelligent objects must be easy in ALL sorts of applications.: Not only in offices, in schools, not only multimedia support, but for home electronics products and for home control. (Remember that the 1980s was the time when PCs made inroads to schools, and offices.)

Again, this sounds so natural and true and is taken for granted today. But in 1989, the view was not universally shared.

As an example for easy HMI in TRON Intelligent House, the switches used in the TRON Intelligent House followed the TRON Human Machine Interface Guideline.[SAKA1991][SAKA1996] The designers were aware of the importance of following basic design guideline based on a design philosophy so that the users can guess the use of different switches based on the previously learned operation of existing switches. Since many partners who built parts of the TRON Intelligent House were not computer manufacturers, the standardizing the design of switches meant the standardization in the physical infrastructure components for homes/buildings for them.

While major computer industry was busy standardizing GUI library for workstation desktop (Windows 3.0 did not appear until the next year), the partners who built the TRON House ADDITIONALLY tried to standardize PHYSICAL switches and the SIMULATED VIRTUAL SWITCHES on the screen on BTRON OS computers used as GUI for the TRON Intelligent House. [SAKA1991b]

HMI specification was later improved from the feedback from professional designers through a couple of design contest, and other application projects. [KOSH1995]

Again, what is described above may seem very similar to the use of HMI on the smartphone to control various electronic devices today, and the readers may wonder why this is stressed in this application submission, but remember it was in the late 1980s when the TRON Intelligent House was designed and implemented. Even today, the standardization of HMI on user devices is not quite polished and often confuse users.

Mechanism for activity coordination

As for the language for control, the data description language and control language were developed. They used the data model adopted in BTRON OS, and made it possible for users to use the APIs of BTRON OS fully from the language to create an application program. [KOSH1988] (N Koshizuka, et al. Implementation Issues of the TACL/TULS Language System on BTRON, pp 113-132, in TRON Project 1989, Springer Verlag), [SAKA1988d][SAKA1988e].

The latter is essentially open API invoked via network in today's parlance.

Data format standardization was carried out in the name of TAD (TRON Application Databus).[SAKA1989b][UESH1991][TRON1994b] Thus, the data from sensors were handled in TAD format on the central home server of the TRON Intelligent house.

Semantic standardization of coordination is the holy grail of IoT research. The research has been going on since the first TRON Intelligent House to today. See [ASAN2016], for example of how uniform handling of different semantics of device operation was proposed.

Such design issues and ideas in computer architectures were presented and discussed at TRON Project Symposium (later renamed TRON Symposium) that has been running for 40 years. [More on proceedings from the symposiums in Appendix VI]

People lived in the house for prolonged time

There have been some SF-like stories and anecdotes of computer assisted living. The movie 2001 Space Odyssey released in 1968 [Kubr1968] depicted space station, and lunar bases with computers, for example. These were discussed in [SAKA1985], and [SAKA1987g].

But a real computer-assisted smart living environment, actually a rather large house, built in the commercial district of Tokyo, a very big city, which was inhabited for an extended period of time was rare. This was one of the first such houses where people lived. This is why the TRON Intelligent House which was built with the notion of HFDS, essentially the concept of the IoT, is deemed the true pioneer of the smart house.

Having people really live inside the house was very important to gather requirements from the residence to feedback the information to the basic research in the HFDS development work.

The difference of this aspect between TRON Intelligent House and other similar activities of the time was noticed by a reporter for Popular Science. Its September 1990 issue covered an European smart house project. [SCOT1990]. In it, it was mentioned that the main person behind the large European smart house project told the reporter the following:

  "It's unlikely that the family home of the future will resemble our
  project," Titulaer admits, "but it generates ideas that may well
  carry over."

The house itself was considered more of an exhibition pavilion than a true house." (Quote from [HOUS2017].)

In contrast, the TRON Intelligent House was lived in for checking out comfort and emergency handling for real. 55 persons in 11 groups lived there after the house was visited by about 10,000 visitors during open house period and was then closed for internal experimentation. [SAKA1991] A brief overview of the survey is in [TRON1994].

Calm technology: hiding the computers and sensors to make the house natural

The TRON Intelligent House hid computers and their control as much as possible to the dismay of some engineers. But this is an important architectural consideration. The service from computers ought to be given as naturally as possible without human intervention and only when it is necessary. If we do not need to be aware of the existence of computers to enjoy the benefit, that will be best. Such an approach of technology adoption was later called Calm Technology circa 1995. [CALM2024].

This architectural characteristic was observed by the Popular Science reporter, who wrote at the beginning of his coverage of the TRON Intelligent House [NORM1990]:

  As I step inside this advanced "intelligent" house, the first thing that strikes me is that it doesn't look like a high-tech wonder. The interior has the spare, clean lines of modern Japanese architecture: Natural wood and neutral colors give it a warm, homey feeling. The south wall is glass, enclosing a two-story atrium filled with trees and plants.

It was also vital to make it easy for the residents to obtain the service from computers. So there was a strong standardization effort to create a uniform HMI including switches that were used in the first TRON Intelligent House.

These aspects of the design philosophy of the TRON Intelligent House set it apart from some computer-controlled living environment depicted in movies and such.

The building architectural design philosophy of TOYOTA PAPI can be found in [SAKA2005] that appeared in [A+U2005] and in Appendix I. Design philosophy of TAIPEI u-home is found in the Appendix II.

Protocols of internal bus inside the houses and buildings

TRON Intelligent House in 1989 tried to realize the IoT network of today using the available hardware and software of the time.

Home bus standards of the day dealt only with audio visual devices

In the 1980s, there were attempts to establish bus structure and protocols used in houses and buildings. They were meant to establish a home bus standard (HBS).[WATA1991]

Typical examples were D2B [D2B1984] from Europe, CEBus [CEBU1989][ESPR1990] from the USA, and Japanese HBS [HOME1988] efforts. It is interesting to note that Popular Science mentioned the effort of smart house construction using CEBus in USA when it also reported the TRON Intelligent House, and a European smart house project.[POPU1990]

Such bus standardization efforts for houses fell much short of establishing usable wiring and bus protocol necessary for the HFDS or the IoT. Basically, they were only for home electronics audio visual equipment, telephone, FAX environment, and maybe power line, too. They did not consider sensors or actuators, the essential elements of HFDS or the IoT. The shortcomings could be listed as follows.

  • (1) such proposed bus standards were basically a bus for AV equipment (not electronic home appliances in general, it is not intended to attach sensors or actuators).
  • (2) Bidirectional (duplex) is possible, but only command transfer (In terms of OSI, they only address the OSI 3 layer and below. There is no upper layer of communication (layer 4-7).
  • (3) The basic topology is a bus or star topology with master-slave host controllers. In other words, the system is not "distributed." (It is not "distributed" because no distributed framework such as HFDS was assumed.)
  • (4) Individual devices were regarded by the host controller as objects to be controlled primarily by polling. In other words, individual devices did not work "autonomously." (To be precise, most of them were not "autonomous.")
  • (5) No coordination between non-autonomous devices (no "cooperation," an unavoidable problem for devices built in the absence of a holistic framework such as HFDS).

The shortcomings, (2), (3), (4), and (5) were direct result of the lack of the holistic approach of the HFDS. Existing devices were not meant for external control by a device from a different manufacturer.

IoT Sensor network in the TRON Intelligent Home

In the TRON Intelligent House, the shortcomings of then current home networks explained in the previous sections were eliminated in the following manner.

First of all, the designers and participating companies in the TRON Intelligent House Study Group understood the notion of HFDS to begin with.

  • (A1) AV equipment was connected, and sensors and actuators were connected.
  • (A2) Communication was bi-directional except for the connection to the external sources. (Please recall that the Internet was not available commercially in 1989.).
  • (A3) Many subsystems have their own autonomous controlling modules in the home server computer.
  • (A4) Many devices created for the TRON Intelligent House had autonomous function with communication capability. Either devices were created from scratch to incorporate these functions, or small microprocessor boards were produced to attach to existing devices to add the required functionality. Basically, such microprocessor boards were created afresh for the TRON Intelligent House. And many were commercialized later.
  • (A5) Home server accomplished the coordination between devices to cause desired behavior of actuators based on sensor data.

The report [NORM1990] of Popular Science September 1990 observed the point two (A2) above correctly and quite clearly. The reporter must have known the shortcoming of the generic CEBus standardization attempt of that time.

Figure from [NORM1990] Overview of the connections inside the TRON Intelligent House

English caption:

 Key to the TRON system is its interactive design. Although the home
 server is a central computer of sorts, it is more a work-flow
 coordinator than controller. Data exchange is two-way between all
 microchip-controlled devices and the server; only outside sources
 are one-way.

The diagram created by Popular Science above captured the essence of communication well, especially the bi-directional nature.

A detailed diagrams in [SAKA1990a] are shown in the following. Each diagram is followed by an English translation.

SAKA1990a-mechanical-systems.JPG Saka1990a-mechanical-systems English-v2.jpg

From [SAKA1990a] Location of Available Functions

SAKA1990a-sensor-network.JPG Saka1990a-sensor-network English-v2.jpg

From [SAKA1990a] The connected devices to support the functions.

Acronyms unfamiliar to readers outside Japan or the current generation of engineers are as follows.

   - BS: Broadcasting Satellite. In Japan, TV channels broadcast via
     satellite are referred as BS in general.
   - BTRON: The BTRON (Business TRON) OS explained elsewhere in this document.
   - ISDN: Integrated Services Digital Network offered by NTT in the
     late 1980s. Back in 1989, it offered 64Kbps speed in its basic
     configuration. It is being phased out in 2024 and will end in 2025.
   - JALCOM was the generic name of the reservation system used by JAL in 1989.
     (There had been JALCOM, JALCOM I, JALCOM II, JALCOM III since 1964)
     It is no longer used now.
   - LD: Laser Disc
   - NTT: Nippon Telegraph and Telephone public corporation

Translation of the caption to the above figure(s).

     The sensor network and the information
  transmission system for transmitting video and audio computer data
  are attached to the house server in the basement. Telephones are
  connected to a digital switching system, video to a head end, and
  audio to a sound controller, and information is exchanged through
  telephone terminals, TV terminals, and speakers installed in all
  rooms throughout the building.

Note by the submitter: A head end (sometimes headend) is a device that is used by the CATV company to deliver what it receives to the CATV transmission line for delivery to the viewer. "The power meters for energy monitoring, water meters" is essentially display of today's HEMS (Home Energy Management System).

Original Japanese in the diagram:

  センサーネットワークと映像・音声コンピュータのデータなどを伝え合う情報伝送 系が地下のハウスサーバーに接続されている。電話はデジタル交換機, 映像はヘッドエンド, 音声は音響コントローラによって 一元化され, 全館全室に設置された電話端子・テレビ端子・スピーカーによって相互 の情報交換がされる

Notes on the protocols used in TRON Intelligent House

There were only a few technical publications regarding protocols due to the nature of privately funded TRON Intelligent House project, except for the few technical publications on top of the diagrams available in [SAKA1990a].

The following explanation demonstrates the TRON Intelligent House built the intra-house networks using existing technology AND newly developed technology and always paid attention to the issues of HFDS realization.

BTRON OS terminals used so called μBTRON Bus for communication with stationery goods.[SAKA1988]. BTRON OS PCs or terminals were connected using full-fledged LAN.

The requirement of such bus connection was outlined on page 128 of in [SAKA1987f] (μBTRON Bus: Design and Evaluation of Musical Data Transfer) That paper explains the pros and cons of μBTRON Bus for transferring musical data from the perspective of YAMAHA who built the acoustic field creation system in the TRON Intelligent House later.

  Quote from the paper:
  The requirements for microBTRON bus are summarized below.
  1) The bus should be capable of controlling several devices simultaneously. In a typical
     application, one microBTRON workstation controls many electronic stationery goods.
  2) Bandwidth should be several megabits per second (Mbps).
  3) The physical cable must be thin and flexible to be used in office environment.
  4) The system operation should not be disturbed severely even if device is connected or
     disconnected, or if the power supply to devices is turned on/off.
  5) The cable, connector, and controller should be inexpensive.
  6) It should be capable of interfacing with HOME BUS (see the explanation about
     HOME BUS below).
  7) Realtime transfer of voice or musical data should be possible.
  8) LAN cable should be extensible to a few hundred meters long.
  9) It should support one hundred nodes at the maximum.

(As for point 3, please recall Wi-Fi or Bluetooth was a long time coming.)

The ongoing standardization in Japan of Home BUS protocol was mentioned and the microBTRON BUS was to talk to HOME BUS network via gateway. Quote from the paper:

  In Japan, HOME BUS standard to facilitate home automation has been
  established since the beginning of 1987. Some electronic appliances
  which conform to HOME BUS have already stated to appear in the
  market. In order to control these devices from BTRON workstations,
  the microBTRON bus should be capable of interfacing with HOME BUS via

So co-existence with other popular bus protocols was paid attention.

[SAKA1987f] further discusses the popularity of MIDI (of that time, 1987. MIDI has progressed much since then) as music data exchange format. The first version of MIDI was standardized in 1983 by MIDI Manufactures Association (MMA).[MIDI] MIDI 1.0 followed in 1995, and MIDI 2.0 followed in 2020.

The following description quoted from [SAKA1987f] was against the MIDI of 1987.

  Some drawbacks have been pointed out as following;
  1) MIDI is one-way serial line per cable and "one to many" broadcast technique without
  hardware handshaking function from the receiver. Large scale MIDI network
  requires too many cables to be connected, making cable routing too complex and too
  2) Baud rate is fixed to 31.25 Kbps. The speed is not fast enough when multiple
  channeled information is transferred, or bulk data transfer is required.
  3) MIDI is "one to many" broadcast technique without hardware handshaking
  function from the receiver. This simple structure makes the mixture of different
  data types (e.g., real time data and file data) to be sent simultaneously on the
  network very difficult.

After evaluating the data transfer patterns of musical performance done by many musical instruments, the microBTRON Bus was to become a lightweight token ring bus. Quote from [SAKA1987f]:

  micro BTRON bus is similar to Token Ring network with the following modifications for
  compactness of the specification and more responsiveness for real time applications.
  1) Smaller frame with shorter address and FCS length.
  2) Limited maximum frame length.
  3) Ability to send consecutive frames from the same node.

Interested readers are referred to the details of microBTRON Bus proposal in [SAKA1987f].

In this way, the new issues encountered in TRON Intelligent House construction as HFDS environment were always in the designers' mind, and solutions were proposed before, during, and after the TRON Intelligent House construction.

For example, [UESH1991] (A fundamental study on picture motion TAD on BTRON specification operating system) is a paper published AFTER the construction in 1989 and evaluation subsequently by residents of TRON Intelligent House.

Please note that MPEG-1 audio layer was standardized only in 1991 and later published as ISO/IEC 1172-3 (MPEG-1 Audio or MPEG-1 Part3) in 1993. [MPEG]

So, video handling in TRON Intelligent House was rather ad hoc at the time, not based on universally recognized standard yet. The data from VCR, laserdisc, or from cable TV feed was handled via special driver tied to the formats on these devices on the BTRON OS PC terminals.

Instead, [UESH1991] proposed the synchronization of audio and visual data, the overlaying of visual data, and other meta-level operations of video (i.e., graphics image) data in a truly exchangeable manner and in real-time fashion. It precedes the efforts of today's video streaming standard effort by a couple of decades, so to speak. It grew out of the necessity to deal with various video and audio data sources simultaneously in TRON Intelligent House project and other projects.

Thus, the TRON Intelligent House did offer much needed requirement specification to the basic research subprojects that comprise the components of HFDS as a whole.

TRON Intelligent House was designed based on the philosophy of HFDS, In return, it helped us to obtain requirements of smart house to strengthen the HFDS concept and helped us to enhance concrete specifications for infrastructure technologies.

Supporting texts and citations to establish the dates, location, and importance of the achievement: Minimum of five (5), but as many as needed to support the milestone, such as patents, contemporary newspaper articles, journal articles, or chapters in scholarly books. 'Scholarly' is defined as peer-reviewed, with references, and published. You must supply the texts or excerpts themselves, not just the references. At least one of the references must be from a scholarly book or journal article. All supporting materials must be in English, or accompanied by an English translation.


* A

[ABAT1990] Fred Abatemarco, Editor-in-chief comment, p 4, Popular Science, September 1990. The whole issue is available online as [POPU1990].

[ALTO] Xerox Alto, Wikipedia
Available online:
It contains many bibliographical references.

[ASAN2016] S. Asano, T. Yashiro and K. Sakamura, "Device collaboration framework in IoT-aggregator for realizing smart environment," 2016 TRON Symposium (TRONSHOW), Tokyo, Japan, 2016, pp. 1-9, doi: 10.1109/TRONSHOW.2016.7842886.


  Device collaboration framework helps diversified interconnected devices to work together to form a smart environment. To realize such device collaboration in practical scenarios, API standardization is necessary to assure interoperability of products from different manufacturers. However, such standardization efforts face limitation and tend to be difficult in the IoT, where target devices are not restricted to specific types of devices, and where manufacturers are strongly motivated to go beyond standards by adding new functions to make their products more attractive than competitors' products. Based on this observation, we have come up with a framework to translate standard API requests to device-specific API requests that devices natively understand. We use so-called device profile, a machine-readable description of device API for translation. Device profile consists of two distinct parts: general device profile (GP) and device specific profile (SP), each of which defines the standard set of API for device class and API conversion rules needed for translation, respectively. Manufacturers can register the profiles of their products in a central repository to publish their new standard set of APIs as GP, and let their products conform to other standards by adding SP. As multiple GPs can be bound to devices, they can support APIs of multiple standards at the same time, regardless of providing only one set of API natively in devices. We have implemented our framework and thoroughly evaluated it with respect to performance, usability, expressiveness, security and scalability. Our evaluation shows that our framework works effectively for realizing device collaboration in practical usage.

[A+U2005] Architecture and Urbanism 2005 Special Issue, A House of Sustainability: PAPI
This is a special magazine issue on TOYOTA PAPI, which is explained in detail in Appendix I.

* B

[BBC1990] 1990: NINTENDO and the JAPANESE SOFTWARE boom | The Money Programme | Retro Computing | BBC Archive, YouTube
This YouTube video covers TRON Intelligent House starting at 417 seconds.
BBC reporters visited the house during the public open period with a group of visitors.
Please note that the news used the term "TRON" in a somewhat sloppy manner. This application form tries to refer to the TRON as the name of the TRON Project which aims at establishing the new computer architecture of the future. However, the BBC video news somehow uses the name, TRON, to refer to the operating systems developed in the TRON Project partners such as BTRON OS, and also other ideas of computer architecture coming out from TRON Project in a mixed manner. Please beware and do not get confused.

[BRIT2024] Entry for TRON 電脳住宅 (in Japanese. Meaning is TRON Intelligent House)
Available online:
This is an excerpt from Encyclopedia Britannica Japanese edition made available through a dictionary service. Having an entry in Britannica shows the wide recognition of the TRON Intelligent House (TRON 電脳住宅 in Japanese) in Japan.
English Translation by the submitter:

  A house with facilities extensively controlled by computer. It was
  designed based on the TRON concept proposed by Ken Sakamura of the
  University of Tokyo. In 1989, a house with more than 1,000 computer
  chips and numerous sensors was completed in Minato Ward, Tokyo, and
  a project team led by Sakamura began a full-scale experiment of an
  intelligent house. In the experiment, the built-in computers
  operated various devices autonomously, and the information and
  operating conditions collected by the computers were transmitted to
  other devices through the network so that they could operate in
  conjunction with each other, thereby providing the house with
  practical and advanced functions such as an alarm system and air
  conditioning system that responds to wind changes. Various studies
  were conducted to provide practical and advanced functions to
  enhance the comfort of living by enabling automatic response of
  lighting to ambient light, and making acoustic system to respond to
  the change of ambient sound, The experiment was terminated in 1993,
  but through these efforts, the idea of incorporating computer chips
  into various places and objects to optimally control the living
  environment became generally known, and research and development
  has continued since then.

Original Japanese in the entry:

  健の提唱した TRON理論に基づいて設計された。 1989年に東京都港区に
  験は 1993年に終了したが,こうした取り組みを通してコンピュータ・チッ

* C

[CALM2024] Calm technology,

[CEBU1989] ISO/IEC JTC1/SC83/WG1 N125: “Consumer Electronics Bus Committee (CE Bus) Draft Physical and Media Specifications”, CE Bus Committee, 1989.

This is the proposal of home bus standard from Europe back in 1989. Phillips chaired the working group.

[CRYS2018] Crystal Hsu, TLDC rebrands to reflect diversification, TAIPEI TIMES Jan 02, 2018
Available online at
The former TLDC, and now renamed Taikai Group had learned of the TRON Intelligent House, then TOYOTA PAPI and sought guidance from Ken Sakamura to build its u-home and then develop Hualien into a smart city.
Excerpts of key paragraphs and sentences:

   Taiwan Land Development Corp (TLDC, 台灣土地開發) is adopting the name Taikai Group (台開集團) and is to raise NT$6 billion (US$201 million) in the next five years to take better advantage of its “smart” city, digital entertainment and preventive medicine businesses.
   The company made its plans known at an investors’ conference in Taipei on Friday last week.
   “We intend to expand our business interests at home and abroad,” Taikai Group chairman Chiu Fu-sheng (邱復生) said.
   Toward that end, the company has adopted a new English name to reflect its diversified businesses that have grown from the development of government-owned industrial parks to the construction of residential complexes, theme parks, retail outlets, hotels and smart cities, Chiu said.
   Several investment projects are about to bear fruit, he said.
   Digital entertainment facility New Paradise (新天堂樂園) in Hualien, which is to be completed by the end of this year, is also to feature assorted sports activities, as well as augmented reality and virtual reality games, he said.
   A flagship Starbucks outlet is due to begin operations in March, Chiu said.
   The group is also to open a hotel with 186 guestrooms in Hualien by the end of next year, as well as teaming up with Marriott International Inc to operate another hotel with 320 rooms under the Aloft brand to court motorcycle riders, he said.
   Aloft Hualien could begin operations as soon as April next year, he added.
   In addition, the group expects to sell its Sunrise Village residential complex in Hualien that features the latest technology and an environmentally friendly design.
   Taikai Group has also inked a cooperation pact with Japanese information science professor Ken Sakamura to turn Hualien into a smart city, making it more friendly for foreign visitors.
   “The company aims to introduce cashless transactions in its facilities as e-commerce grows in popularity,” Chiu said.

* D

[D2B1984] “D2B Specification”, Mullard Limited, Publication, Bo. 62833801, 1984.

Developed by Phillips. It is a bi-directional protocol meant for audio visual devices, and uses paired cable. It was first proposed to IEEE in 1981 as D2B (Domestic Digital Bus). It was proposed to IEC/TC84/WG12 in 1986.

* E

[ESPRI1990] ISO/IEC JTC1/SC25/WG1(WG12) N215: “Media and Interface Specifications for PL, TP, CX, IR and Radio”, ESPRITHS Project, 1990.

This standardization activity was mainly done by organizations/enterprises from USA. Japanese Home Bus System was proposed to this working group.

* F

* G

* H

[HOME1988] EIAJ: ”Home Bus System”, ET-2101, 1988.
Japanese Home Bus System standard draft.

[HOUS2017] House of the Future, Rosmalen Archived October 19, 2007, at the Wayback Machine
Available on line at
This is a short description of the house of the future, archived at Way Back Machine. The house was created by Chriet Titulaer, (wiki: ) mentioned as the leader of the European smart house project by [POPU1990]. PLEASE NOTE THAT THE DESCRIPTION BELOW IS BASED ON THE ONE ARCHIVED IN 2017. The functions back in 1990 therein may not have been as functional as described there. Quote from the Way back machine archive:

   client: BV Huis van de Toekomst, Rosmalen
   The House of the Future was built to show a wide public that with
   the aid of technical innovations, living in the immediate future
   could look utterly different from the way it is now. Beside the
   house itself, the complex includes a prefatory building comprising
   the entrance, a film theatre, and a shop; the whole standing on an
   island in a lake near the Autotron in Rosmalen. The house and the
   additional building are linked by an all-glass bridge across a
   tiled ornamental pond. Next to the house is a garden enfolded by a
   semicircular concrete wall, and a pool in which stands a glazed
   tea house.
   In principle, the House of the Future contains the same functions
   as those familiar to us from the traditional house – kitchen,
   bathroom, dining room, living room, bedrooms, etc, but in an open
   spatial composition strengthened by a lavish use of glass
   partitions, voids, and views through. Because it is more an
   exhibition pavilion than a true house, it is somewhat larger than
   normal. The internal subdivision is open to rearrangement; the
   roof garden includes a reception area for visitors. New techniques
   have been assimilated in the architecture as much as
   possible. Thus the structure involves concrete panels reinforced
   with arapree, enabling it to take greater, freely subdivisible
   spans. The glass in the bedrooms can be rendered opaque
   electronically, and there are, of course, videophone facilities
   and a cable system enabling communication between personal
   computers. In the way of gimmicks, the bathroom roof can be opened
   or closed in response to the human voice. The house can be
   analysed as a number of components each with its own design, and
   maintaining its status as independent element within the
   composition as a whole.  

* I

[i386] i386 wiki entry,

[IEC2001] “Guidelines for the user interface in multimedia equipment for general purpose use", Technical Report IEC TR 61997, 2001.
Available Online: (Retrieved September 20, 2022,

This describes the new (2017) campus building INIAD HUB-1, built using the current IoT technology and is used for education and research for the IoT.

The English translation of the page is in Appendix VII.

[ITU2015] ITU 150 Award; (Retrieved September 20, 2022,
Ken Sakamura received the ITU 150 Award in 2015.

  Citation:Ken Sakamura – ITU 150 Award
  Born in Tokyo in 1951, Ken Sakamura received a Ph.D. in Electrical Engineering from Keio University, Japan in 1979, and subsequently became a research associate at the University of Tokyo, where he has stayed ever since. Currently, he is a professor of the Interfaculty Initiative in Information Studies at the Graduate School of the University of Tokyo, the director of the YRP Ubiquitous Networking Laboratory (UNL for short), and the chair of TRON Forum and uID Centre. He has been the leader of TRON Project since 1984, and has designed the TRON open computer system architecture which will be useful for ubiquitous computing of the future. Today, the real-time operating systems based on the TRON specifications are used for engine control on automobiles, mobile phones, digital cameras, and many other appliances, and are believed to be the among most popular operating systems for embedded computers around world. The R&D results from TRON Project are useful for ubiquitous computing. For example, UNL joined the standardization efforts at ITU-T and helped produce a series of Recommendations, including H.642 “Multimedia information access triggered by tag-based identification”. The idea behind H.642 series is based on de facto “ucode” standard developed by UNL for communication in the age of the Internet of Things. For his achievements, Sakamura has won many awards: Takeda Award, the Medal with Purple Ribbon from Japanese government, Okawa Prize, Prime Minister Award, and Japan Academy Prize. He is a fellow and the golden core member of the IEEE Computer Society.

* J

* K

[KOSH1988] N Koshizuka, et al. Implementation Issues of the TACL/TULS Language System on BTRON, pp 113-132, in TRON Project 1989, Springer Verlag


  In the computer systems of the TRON Project, many interfaces are described with TULS (TRON Universal Language System). TACL (TRON Application Control-flow Language) is a language based on TULS which defines the protocol between the end user and the BTRON system. TACL can describe various programs such as batch programs, home automation control programs, and some application programs of BTRON. This TACL/TULS language system consists of four components: the TACL/TULS Manager, the Dictionary Manager, the TACL/TULS interpreter task, and the TACL/TULS program editor.

[KOSH1995] N. Koshizuka, T. Muto and K. Sakamura, "Human-machine interface specifications in the "computing everywhere" age," Proceedings of the 12th TRON Project International Symposium, Tokyo, Japan, 1995, pp. 87-90, doi: 10.1109/TRON.1995.494745.


  In the near future, computers will be embedded in all kinds of facilities. They will be connected by computer networks, cooperate with each other, and support our daily life. In such a "computing everywhere" environment, human beings will be surrounded by numerous computers and use them anytime anywhere. Thus, in the "computing everywhere" environment, human interfaces to embedded computers are very important. We have built TRON Human-Machine Interface Specification to make human-machine interfaces in the "computing everywhere" environment consistent and to free users from confusion in using many kinds of electronic equipment. This paper describes the design philosophy and technical/theoretical background of our specification.

[KUBR1968] 2001: A Space Odyssey,

A movie directed by Stanley Kubrick based on the script by Arthur C. Clarke. It was made in 1968 and the dialog of computer HAL with astronauts in the spaceship to Jupiter is legendary.

* L

* M

[MaciII] Macintosh II, Wikipedia entry
Available online:
It has enough bibliographic references.

[MIDI] MIDI, Wikipedia entry

You can find relevant references about MIDI here.

[MONO1996] TRON House / Intelligent House is operated by an independent researcher, a retiree from Musashino Institute of Technology where he gave lectures on architecture design in graduate school with his collaborators. The content of the web site is about the future houses and buildings.
Translation of the first section: (note: there is a typo of the year in which the TRON Intelligent House was built. It was in 1989, not in 1990.)

  TRON House, built in 1990 in Roppongi, Tokyo, was constructed by
  the TRON Intelligent House Study Group, a group of 18 companies,
  and was designed and supervised by Ken Sakamura, assistant
  professor at the University of Tokyo, as part of the TRON Project.
  TRON Project is proceeding in search of the ideal computer society
  of the future, and in turn, is considering what to start now.
  The TRON house explored the true potential of an intelligent house:
  a system that integrates a variety of functions, coordinates them
  in a finely tuned manner, and is easy for anyone to use, rather
  than a collection of disparate devices and half-baked home
  automation systems.
  Thus, in the TRON House, all facility equipment was organically
  connected to create a system that enables unified control, so that
  complex functions can be used through simple operations. This was a
  very difficult task.
  There were two objectives. The first was to make it possible for
  the equipment to cooperate with each other. Cooperative operation
  enables more comfortable and economical control.
  The second was to improve usability. By unifying the operability,
  the same steps can be used for different types of equipment.

Japanese Original:


There are enough references in the wiki entry about MPEG in general.

* N
[NEWS2019] Ken SAKAMRUA: Cohabitation with AI, House As A Service (HaaS), the near-future building scenario (original Japanese: 【坂村健】「AIと同居」「HaaS」…近未来の住宅はこれだ)
This website is published by Nikkan Kogyou Shimbun, a large nation-wide trade newspaper on industry.
The translation of the first question from the interviewer, which shows that the wide recognition of the TRON Intelligent House in 1989 was the first "smart house" in Japan:

  Compared to past demonstration houses such as the "TRON Intelligent
  House" developed by Takenaka Corporation and others in 1989, what
  are the features of the concept of the "Open Smart UR Startup
  Model," the near-future house developed with UR?

Original question in Japanese:

  住宅と比較してURと開発した今回の近未来住宅「Open Smart UR スター

[NHK1987] コンピューターの時代 教育テレビスペシャル (in Japanese)
Age of Computers, special program series on education channel, NHK

This was a series of programs focused on computers and how it would impact our lives. Aired in 1987, the fourth installment of this series featured BTRON OS computers and its desktop very well.

The fourth installment of the series has been uploaded on YouTube by someone. BTRON desktop with embedded video recording is shown in

A vision of the future house, which was implemented in the TRON Intelligent House can be seen starting around 39:25.

[NIKK2020] Third generation Intelligent House created by Ken Sakamura using IoT and AI (original Japanese title: 坂村健氏がIoT・AIで創る第三 世代の電脳住宅とは )
This is a website of journal publishing company of Nikkei Newspaper group. The first interviewer recognizes that TRON Project and the TRON Intelligent House predated "the IoT".
The translation of the first interviewer question:

  In the 1980s, when the term "Internet of Things (IoT)" had not yet
  been coined, Dr. Sakamura envisioned a society in which computers
  would be placed inside tangible objects and all of these objects
  would be connected via the computer networks, and you launched the TRON
  Project, an open computer architecture project for realizing this
  vision. As part of this project, the TRON Intelligent House built
  in 1989 in Roppongi, Tokyo, was an experimental house based on the
  very idea of the IoT of today.

Japanese original:

  坂村先生は、IoT(Internet of Things)という言葉がまだない1980年代か

[NORM1990] Dennis Normile, From Japan: Intelligence with Classic Style, Popular Science p 58-61, Popular Science, September 1990

The whole issue of Popular Science is available online:

This is a very objective third party report of the TRON Intelligent House.

  p.58 Right column.
  Architectural design philosophy.
  Home server
  p. 59 Left column, the first paragraph
  Limitation of the CPUs of the devices. Home server p. 59, central
  column, the third paragraph.
  p. 60 second paragraph in the middle column.
  coordinated behavior
  p. 60 central column.
  HVAC system
  p. 60, right column TV and audio.
  p. 60 right column
  disaster simulation / robustness of distributed nature
  Figure on p. 60.
  Data exchange is two-way between all microchip-controlled devices and the server.; only outside sources are one-way.
  (Submitter's note: in today's cloud environment, even the outside source could be two way.)
  p.61 Start from clean slate

* O

* P

[POPU1990] Popular Science September 1990 issue. This issue is available online:

[POPU1990b] "The Best of What's New, Home Technology award"
The following is the printed award Ken Sakamura received in 1990. By courtesy of Ken Sakamura. PopularScience-1990-Award.jpg

* Q

* R

* S

[SAKA1982] Ken Sakamura, コンピュータとどう付き合うか: 文化系にもわかる最新技術情報 (in Japanese) How to cope with computers: the latest technology explained to non-techies (in Japanese), Ken Sakamura, published by Koubunsya, November 1982

The title of the book says it all. It is meant for non-computer professionals.

[SAKA1985] Ken Sakamura, 電脳都市: SF と未来コンピュータ(初版) (Intelligent City: SF and future computers (first edition), Ken Sakamura, 303 pages, published by Tojyusya, 1985.

This is the first edition of [SAKA1987g] published two years later.

[SAKA1987] K. Sakamura, "The Tron Project," in IEEE Micro, vol. 7, no. 2, pp. 8-14, April 1987.
doi: 10.1109/MM.1987.304835.
Available online:


  TRON designates a family of architectures, operating system
  kernels, and VLSI CPU chips. It is an open specification, intended
  to foster the development of compatible products by many vendors.

[SAKA1987b] Ken Sakamura, "Looking into the Future with TRON," in IEEE Micro, vol. 7, no. 2, pp. 4-6, April 1987, doi: 10.1109/MM.1987.304832. URL:

  TRON designates a family of architectures, operating system kernels, and VLSI CPU chips. It is an open specification, intended to foster the development of compatible products by many vendors.

[SAKA1987c] Ken Sakamura, “BTRON: Human-Machine Interface”, Proceedings of the Third TRON Project Symposium, "TRON Project 1987 Open-Architecture Computer Systems", pp. 83-96, Springer Verlag, 1987. Abstract:

  BTRON is an operating system architecture designed in the TRON project. BTRON specification aims at establishing operating systems for workstations in 1990's. BTRON workstations will offer ease of use and learning, efficient operation for experienced users, support for many languages of the world including the support for many character sets, data interchange across different BTRON machines, consistent data model, uniform man-machine interface, and a set of functions which will make it easy for application developers to build programs that use similar man-machine interface.

[SAKA1987d] Ken Sakamura, The Objectives of the TRON Project, in the proceedings of the third TRON Project Symposium, "TRON Project 1987 Open-Architecture Computer Systems", pp. 3-16, 1987. Springer Verlag, ISBN: 978-4-431-68071-0

  HFDS (Highly Functionally Distributed System) is heterogeneous loosely coupled computer network and generally has large number of computers including large number of intelligent objects.
  The TRON project has been under way to bring the dream of computerized society, where HFDS's play important roles, into reality. The project will produce ITRON, BTRON, CTRON, MTRON, and TRON VLSI CPU when it is finished.
  ITRON is a real-time OS specification for embedded computer systems.
  BTRON is an OS specification for workstations, and it will define TAD (TRON Application Databus) data exchange standard.
  CTRON is an OS specification for servers and gateways on HFDS. MTRON is a network OS specification to control the operation of HFDS's.
  TRON VLSI CPU will run the TRON based software systems efficiently.
  The long-term objective of the TRON project is to realize an HFDS by utilizing the results of these subprojects.

[SAKA1987e] K. Sakamura, "BTRON: THE Business-oriented Operating System," in IEEE Micro, vol. 7, no. 2, pp. 53-65, April 1987, doi: 10.1109/MM.1987.304846.


  Designed for use with office workstations with bitmapped displays, this operating system offers a uniform man-machine interface and data transportability.

[1987SAKAf] K. Sakamura, K. Tsurumi and H. Kato “µBTRON Bus: Design and Evaluation of Musical Data Transfer,” TRON Project 1987 (Proc. of the Third TRON Project Symposium), pp.127–138, Springer-Verlag, 1987.


  μBTRON bus is designed to connect electronic stationery goods to BTRON-based workstations. The design objectives of μBTRON bus are described and then the performance of musical data transfer on the bus is discussed according to simulation results. The results show that the μBTRON bus offers satisfactory performance for this application.

[SAKA1987g] Ken Sakamura, 新版 電脳都市 (New Edition: Intelligent City in Japanese) , Ken Sakamura, 1987, Published by Iwanami Shoten, November 1987

This is about the vision of the future Intelligent City (today's Smart City) including the vision of the house. Anecdotes and potential scenarios were taken from many SF novels with the interpretation by the author. This was meant for the general audience as well as people in the IT industry.

This is an edited version of the earlier [SAKA1985].

There is a reader's review posted in 2007 that read as follows at
Translated by this Milestone application submitter.:

     This book takes various science fiction novels as its subject and predicts the future cybercity.
     I admire the author for not just dreaming up the idea, but for
     subsequently spreading the results of TRON Project that would
     implement such cyber cities to the rest of the world.
     JP Hogan's science fiction novels depicted the ubiquitous society itself.
     I admire the fact that this book was published 20 years ago, and
     to be precise, I own the original, not a new edition, so that
     means 22 years ago.

[SAKA1987h] Ken Sakamura, TRON からの発想 (New Concepts from the TRON Project in Japanese), published by Iwanami Shoten, Feb. 1987.

This book explains TRON Project, HFDS, various real-time OSs for different applications, etc. to the general public as well as people in the IT industry.

[SAKA1987i] Ken Sakamura, TRON を創る: Making of TRON (in Japanese), published by Kyoritsu Shuppan, Jan 1987.

This is an introduction to the TRON Project and what it aims to achieve for engineers.

Abstract available at Japan Amazon site: Translated into English.

  TRON stands for "The Realtime Operating System Nucleus. However, the TRON project is not just a project to re-create operating systems, but a grand project to rebuild the VLSI CPUs, OSs, and even the human-machine interface, the rules for how computers and humans interact with each other, while keeping an eye on the technological standards of the 1990s (and beyond).
  Unlike the conventional steps of introducing the latest results of science and technology, in which the necessary corresponding social design is done after the product has been developed, TRON Project first conducts social design and then feeds it back to the product development process. In addition, TRON Project attempts to address distortions in the computer systems that cannot be resolved by individual performance improvements and technological advances alone, by adjusting the computer industry as a whole to address distortions caused by the lack of uniformity and/or holistic approach in the past. The TRON Project also includes a number of new concepts, such as the inclusion of multilingual and multimedia functions, based on the premise of a 21st-century society in which computers are seen as tools for communication.
  This book is primarily an introduction to TRON Project for engineers, providing an in-depth description of the TRON Project's starting point in understanding the technical issues involved and how it views the technology surrounding computers.

Original Japanese:

  TRON とは"The Realtime Operating System Nucleus"(実時間処理に適したオペレーティング・システムの核) の略である。しかし、TRON プロジェクトは単にOSを作るというだけのプロジェクトではなく、90年代(これから)の技術水準をにらみながら、VLSI、OS、コンピュータと人間との付き合い方のルールであるマンマシン・インタフェースまでも作り直すという壮大なプロジェクトである。
  製品ができてから対応する社会デザインが行なわれるといった従来の科学技術の導入ステップではなく、TRON ではまず社会デザインを行なってからそれを製品の開発にフィードバックしようとしている。このような点や、個々の性能向上や技術進歩だけでは解決できない、従来の統一的に作られていなかったためのコンピュータの歪みに対して、コンピュータ産業全体としての調整を行なうことにより対処しようとしていること、さらに21世紀の社会を前提とし、コンピュータをコミュニケーションの道具ととらえて、多国語やマルチメディアなどの機能を持たせていること、など多くの新しい概念をTRON プロジェクトは含んでいる。
  本書は主にエンジニアのためのTRON の入門書である。TRON プロジェクトがどのような技術的な問題点の把握を出発点としているのか、またコンピュータ周辺の技術をどのように見ているのか、といったことについて突っ込んだ記述をしている。

[SAKA1988] K. Sakamura et al., The μBTRON Bus: Functions and Applications Pages 101-112, TRON Project 1989, Springer Verlag


  In addition to the BTRON bus which is used as a heavy-duty LAN, the BTRON standard includes the μBTRON bus, which is a simple LAN used to connect a BTRON-based workstation with electronic stationery goods. The μBTRON bus is intended to be a low-cost LAN which takes advantage of the following features of TRON.
   1) Realtime response
   2) Ease of use
   3) Compatibility
  In order to provide realtime response, the μBTRON bus is a token ring type LAN, but from considerations of ease of use, cable routing has been simplified so that it can be done by non-technical users. Standardization is expected to bring cost reductions of the basic devices.
  It is expected that the use of systems such as Home Bus system and ISDN will continue to spread. By interconnecting with these systems, we expect that BTRON will find even wider application as the home network for the 1990s.

[SAKA1988b] K. Sakamura, Design of MTRON: Construction of the HFDS, TRON Project 1988, The proceedings of TRON Project Symposium, Springer Verlag


  MTRON (Macro-TRON) is the network architecture for building the HFDS (Highly Functional Distributed System) in the TRON Project. Nodes with embedded microprocessors in an MTRON network are called intelligent objects The HFDS is designed to be scaled into a very large network consisting of vast numbers of such intelligent objects. The HFDS needs various forms of data and real-time communication services, which MTRON is designed to provide using a composite layered architecture approach. Applications in the HFDS include management of buildings. In order to handle the position-dependent processing of intelligent objects inside a building, MTRON is specifically designed to handle the concept of the physical position of a node. In order to communicate with the large number of nodes that will be connected to networks in the future, communication protocols are defined dynamically using TULS (Tron Universal Language System).

[SAKA1988c] K. Sakamura TRON概論 (Overview of TRON Project in Japanese), published by Kyoritsu Shuppan, June 1988, ISBN 9784320024090

This is a Japanese translation of the articles in May/April 1987 issue of IEEE MICRO. This was done to introduce technical aspect of the TRON Project to the engineers in Japan. The May/April issue was considered very handy since it assembled the articles from many authors and covered the whole activities of TRON Project back then.

English Translation of the book's summary:

  This is the complete and expanded edition of the 1987 IEEE MICRO special issue on TRON Project. It consists of an overview of the project as a whole, and an overview of the I, B, and C TRONs and TRON chips.
  For the TRON project, the background of the project, its necessity, and the design approach common to all TRONs, such as the concept of architectural series and layers, are described.

For ITRON, its features, task state, system control, etc. are described. For BTRON, its design goals, approach, and technical features such as the real/virtual object model and TAD are described. For CTRON, the design concept, design policy, etc. are described, and the various models considered in the design are explained. The TRON VLSI CPU chip is described, including its instruction set, addressing mechanism, and comparison with other 32-bit MPUs.

  In this way, this book is ideal for getting a concise technical overview of the TRON project. It is also a good introduction to the products that are being developed at the product level based on the TRON specification, and is suitable as a primer before learning more about the specifics of each TRON product.

Original Japanese description:

  本書は、1987年の IEEE MICRO誌のTRON特集の完訳増補版である。プロジェクト全体の概論、I、B、C の各TRONや TRONチップの概論よりなっている。
  TRONプロジェクトにおいては、プロジェクトの背景、その必要性、アーキテクチャのシリーズ化とレイヤの概念などすべてのTRONに共通の設計アプローチについて述べている。ITRONでは、その特長、タスクの状態、システムコントロールなどについて解説している。BTRONについては、その設計目標、アプローチについて述べ、実身/仮身モデルやTADなどの技術的特徴について述べている。また、 CTRONについては、その設計概念、設計方針などについて述べ、設計において考慮された各種モデルについて解説している。さらに、TRON チップについては、そのインストラクション・セット、アドレッシング・メカニズムについての解説、さらに他の32ビット MPUとの比較などについてのべている。

[SAKA1988d] Ken Sakamura, TACL: TRON Application Control-flow Language, TRON Project 1988, The proceedings of TRON Project Symposium, Springer Verlag

  In the TRON Project, many interfaces are described in extensible
  manner using a language called TULS (TRON Universal Language
  System). TACL (TRON Application Control-flow Language), which
  provides a programming, environment on BTRON is based on TULS. The
  execution of TACL is done by the expansion of macros. It uses
  volatile dictionaries stored locally, and permanent storage in the
  form of real objects, which are the same as the real/virtual
  objects of BTRON data model. Macros are defined in the
  dictionaries. Display of data inside a window is done by
  interpreting the content of data as a TACL program. TACL handles
  external events, such as those from devices, as part of macro
  processing. the dictionaries used in TACL offer a versatile
  processing capability.

[SAKA1988e] Sakamura, K. (1988). TULS: TRON Universal Language System. In: Sakamura, K. (eds) TRON Project 1988. Springer, Tokyo.


  In future computer systems based on TRON specifications, various interfaces will use programming languages. The basic specification for such languages in building these interfaces is TULS (Tron Universal Language System).
  This paper explains the motivation behind the use of programmable interfaces.
  In this paper, the design of TULS is explained along its philosophy. An example of a TULS application is the physical data layout format of TAD (TRON Application Databus), which is described using TULS.
  TULS is meant to provide programming capability for various types of interfaces.
  The specification of the interfacing parts of computer systems can be dynamically changed for optimum load balancing using TULS.
  This makes it possible to adapt the interfaces to new technologies that will emerge in the future, while maintaining compatibility over the long run.
  TULS will be used for data representation, the human interface, network protocols, user programming interfaces, system program interfaces, etc. BTRON, ITRON, and CTRON will use TULS.
  TULS is what makes the building of the MTRON environment possible.

This paper describes TULS (Tron Universal Language System), which was at the core of application programming language of MTRON back in the 1980s.

[SAKA1989a] Ken Sakamura and Richard Sprague, The TRON Project, p. 292 - , BYTE April 1989

This issue is available online:


  An open architecture, a family of VLSI chips, and system software
  designed to revolutionize the way we use computers

This is an introduction of the TRON Project in 1989 to the audience of very popular PC magazine about personal computing. BYTE magazine was a highly esteemed magazine on personal computing at the time.

BYTE magazine was widely read in the IT industry, and by hobbyists also, and one of THE periodicals for personal computing, which inherited the spirit from the early days of microprocessor deployment on the west coast of USA in the 1970s.

[SAKA1989b] An overview of BTRON/286 specification, Ken Sakamura, Y. Kushiki, K. Oda, p 14-25, IEEE Micro ( Volume: 9, Issue: 3, June 1989)

This explains the implementation of BTRON OS on Intel 80286 CPU. More importantly, it explains TAD (TRON Application Databus) format.


  A description is given of BTRON, or Business TRON, a set of operating system specifications for workstations and personal computers that use bitmapped displays. BTRON is a 16-b version of the Japanese TRON project's 32/64-b architecture, designed to be more affordable and fill business data and graphics needs. The primary goals set for BTRON call for the realization of easy operation through a standardized human-machine interface (HMI) and the assurance of data compatibility across different applications and machines. BTRON establishes a method for exchange data and control across applications, and it realizes a document management system in which text and graphics can be mixed freely and layouts handled with ease. It offers standard support of English, Japanese, and other languages, providing a wide variety of fonts. Basic services of the operating system nucleus that are examined are process, file, event, device, and real and virtual object management. TAD (TRON Application Databus) is also explained

[SAKA1990a] K. Sakamura, TRON Intelligent House, Shinkenchiku/新建築 (New Architecture in Japanese) vol 2. In Japanese.

This article is one of the few available detailed descriptions of the TRON Intelligent House by its designer. It appears in a magazine for construction industry.

A photocopy of the article will be sent to the history committee.

[SAKA1990b] Ken Sakamura, The TRON Intelligent House, IEEE MICRO p.6-7, April 1990.
(Strangely, this is not available in IEEE Xplore. A full scanned copy will be sent to ETHW mail address.)
The first two paragraphs:

  The cover of this issue depicts the
  TRON Intelligent House built in
  the Roppongi district of Tokyo.
  approximately 1,000 computers interact
  to support this house. The direct cost of
  building on this 300-square-meter lot
  was 1 billion yen (US$6.7 million), and
  the additional indirect costs reached 2
  billion yen (US$13.4 million).
  The TRON Intelligent House is the
  experimental prototype of the future
  house, which incorporates the results of
  the TRON Project that proceeds under
  my leadership. The house reflects my
  idea of the house of the future. Many
  parts of the TRON House have sensors,
  computers, and actuators. These network-
  connected devices can work with
  each other in a cooperative manner. For
  example, if the controls of two subsystems
  seek conflicting objectives, an
  overall control instructs them to compromise.

The rest of the paragraphs are quoted in the main text. (Submitter's Note: There seems to have been a typo.: 300-square-meter ought to read 333-square-meter.)

[SAKA1990c] Programmable interface design in HFDS in TRON Project 1990, pp. 3-22, Springer Verlag, 1990.


  A programming/communication model on a shared memory base is proposed as a framework for devising standard interface specifications, in a large-scale, loosely coupled distributed environment. Although this model assumes a shared memory base, it is designed to allow different access mechanisms, structures, and a diversity of practical restricting conditions to be introduced at the model level to account for specific applications. The model integrates common data spaces found in a variety of applications, making it possible to realize compact interface specifications optimized to each application.
  The aim behind this model is to realize programmable interfaces, as required in implementing the highly functionally distributed systems (HFDS) that are an ultimate objective of the TRON Project. By realizing programmable interfaces on this model, it will be possible to achieve commonality among each of the interfaces in HFDS, and at the same time to allow interface expansion to adapt to technological advances and to application differences.

[SAKA1991a] K. Sakamura, "Human interface with computers in everyday life," Proceedings [1992] The Ninth TRON Project Symposium, Tokyo, Japan, 1992, pp. 2-12, doi: 10.1109/TRON.1992.313273.

This article explains the philosophy and the positioning of HMI in TRON Project, including its use in TRON Intelligent House.


  The computerization of equipment making up our ordinary living environment is proceeding rapidly, and the networking of these computerized objects is likely to become a major issue in the future. Embedded microchips endow equipment with advanced functions, often bringing the need for a high level of information exchange with users. For this reason, human/machine interface (HMI) with computerized objects requires at least the same level of advancement and standardization as HMI in personal computers and workstations. The author discusses the concepts and policies being incorporated in the TRON Project's standardization of HMI, based on the above premises. He describes the 'TRON Human Interface Specifications for Computers in Everyday life' as a specific result of these standardization efforts.

[SAKA1991b] K. Sakamura, "TRON application projects: gearing up for HFDS," Proceedings Eighth TRON Project Symposium, Tokyo, Japan, 1991, pp. 2-14, doi: 10.1109/TRON.1991.213121.

This paper surveys the status of various application subprojects of TRON Project including the TRON Intelligent House. It is a handy reference to then on-going follow-up projects on smart buildings, smart cities, and smart transportation then.


  The TRON project, which is designing new computer architectures premised on the applications of the future, is being carried out in two kinds of subprojects. The foundational projects are researching and developing computers themselves, while the application projects are looking into future computer uses. The application projects play an essential role in achieving the ultimate goal of the TRON project, which is to realize highly functional distributed systems, or HFDS. In the HFDS concept, as more and more objects in our living environment are given microchip intelligence, their functioning can be made much more effective by networking them in loose alliances that will allow them to coordinate their activities. The TRON application projects are exploring HFDS possibilities through actual implementations, and are introduced here from this standpoint.

[SAKA1993] K. Sakamura eds, "TRON 電脳生活ヒューマンインターフェイス" TRON Computerized Living Human Interface Standard Handbook", published in 1993.

The content of this book was superceded by [SAKA1996]

[SAKA1993b] K. Sakamura, "Guest Editor's Introduction: Toward a World Filled with Computers" in IEEE Micro, vol. 13, no. 05, pp. 6-11, 1993.
DOI: 10.1109/MM.1993.10044
Available online:

This article describes the cycle of forecast, design, develop and obtain feedback of TRON Project activity succinctly.

Excerpt from page 9 of this article on TRON Project update:

  TRON Project update
  The TRON Project is looking ahead to a world filled with
  computers. As I noted at the beginning of this piece, interest
  is beginning to focus on environments that are filled with
  computers everywhere you look. The TRON Project has constructed
  a pilot TRON-concept Intelligent House (ref 4,5)  with around
  1,000 built-in computer elements. We are about to begin construction
  of the first TRON-concept Intelligent Building that
  incorporates tens of thousands of computers.
     What sets the TRON Project apart is its attempt to get a
  jump on the next computer age by considering what kinds of
  computer applications are likely to emerge, actually building
  such applications, and feeding hack the results into the design
  of basic components such as microprocessors and operating
     Besides trying to determine the most suitable architecture
  for an age when the number of microchips in use is thousands
  or ten thousands of times greater than today, this project
  takes a comprehensive look at questions such as the following.
  What should computers be made to do? What should
  they not be made to do? What kinds of infrastructures are
  needed? What rules are necessary for data interchange? In
  these ways the project is planning and building information
  infrastructures for the future.(ref 6)”
     From the TRON Intelligent House to the TRON Hyper-
  Intelligent Building. We completed the TRON-concept Intelligent
  House experiment, conducted as an application
  project to get an advance look at the future, in the spring of
  1993. (Submitter's note: this means the project was finished in
  1993) At the same time we finished the basic design of the
  TRON Hyper-Intelligent Building, incorporating tens of thousands
  of computer elements, in preparation for the start of
  construction later this year. (See Figure 2, next page.)
     The significance of this project is that a life-size model of a
  “computers everywhere” building will be built and put to
  actual use as a place of work. The building’s computers will
  be able to locate people wherever they go and will fine-tune
  lighting (see Figure 3), temperature, and other environmental
  factors to personal preferences. The overall model is that
  described earlier of “intelligent objects” (ordinary objects containing
  microchips, sensors, and actuators> linked in wired or
  wireless networks that enable them to coordinate their actions.
  The component parts making up these networks are
  the results of fundamental research and development taking
  place in the TRON Project. In addition to the microprocessors‘
  used to control the intelligent objects, these important
  development results include real-time operating systems, highlevel
  data interchange protocol, and human-machine interface
  4. Ken Sakamura, “About the Cover: The TRON Intelligent House,”
  IEEE Micro, Apr. 1990, pp. 6-7.
  5. Volker Hartkopt et al., Designing the Office of the future: The
  Japanese Approach to Tomorrow’s Workplace, John Wiley &
  Sons, New York, 1993.
  6. Ken Sakamura, “TRON Application Projects: Gearing Up for
  HFDS,” Proc. Eighth TRON Project Symp., IEEE Computer Society
  Press, Los Alamitos, Calif., 1991, pp. 2-l 4.

Ref 4 is [SAKA1990b], and Ref 6 is [SAKA1991b] in this bibliography.

Unfortunately, the economic bad turn in Japan in the 1990s cancelled the building the office of the future.

[SAKA1995] K. Sakamura, "Bibliography of the TRON project (1984-1996)," in TRON Project Symposium, Tokyo, JAPAN, 1996 pp. 144-175. doi: 10.1109/TRON.1996.566206

  Abstract: Activities of the TRON Project in the past twelve years (1984-96) have produced a large amount of technical results which are published as papers, books, and reports. Because such publications of TRON are scattered among diverse journals, proceedings, technical reports, etc., it is difficult for the new TRON researchers and developers to discover relevant documents. The primary objective of the bibliography is to eliminate this difficulty, and to improve the accessibility of technical information of the TRON Project. Its contents are restricted to publications on technical issues. At present, the bibliography contains more than 600 entries. Entries in this bibliography are classified into ten sections by their interests: books on the TRON Projects, specifications and technical papers on general issues, on TRON Specification CHIP, on ITRON, on CTRON, on BTRON, on HMI, on Enableware, and on MTRON/HFDS.


[SAKA1996] Ken Sakamura eds, トロンヒューマンインタフェース標準ハンドブック in Japanese
TRON Human Interface Standard Handbook, TRON Electronic device HMI study group (tentative English translation), published by Personal Media Corporation, 1996. ISBN 978-4-89362-141-2

It is actually a re-issue of an improved version of the earlier [SAKA1993] published in 1993. The essence of this document is published as [IEC2001]

See the description at (in Japanese)

[SAKA1998] "μITRON3.0 An Open and Portable Real-Time Operating Systems for Embedded Systems", Ken Sakamura, April 1998, IEEE Computer Society Press, ISBN:‎ 978-0818677953

This is an English book on μITRON3.0 specification and with an introduction to RTOS programming.

[SAKA2005] Intelligent House in the Age of Ubiquitous Computing, Ken Sakamura, pp. 56-65, Architecture and Urbanism, December 2005 Special Issue, House of Sustainability: PAPI (referenced as [A+U2005] in the application text.)

This special issue of a magazine contains an article by SAKAMURA that includes the overview of the TRON Intelligent House in 1989 (Ver 1) from the viewpoint of Ken Sakamura in 2005 as hindsight.

Excerpts will be sent to the history committee.

[SCOT1990] From Europe: Bauhaus with Brains, David Scott, Popular Science pp. 62-65, 102, September 1990.

This issue is available online:

This describes the smart house being built in Europe at the time. Unlike the TRON Intelligent House, it was never meant to be a house to be lived in for long.

Foreword and the first three paragraphs:

  Holland's striking entry in the home-
  automation tournament shelters a col-
  lection of integrated electronic systems in a
  geometric structure that is itself a
  showcase of future technology.
  Conventional ideas do not cloud the vision of Chriet Titulaer, who
  sees a future rife with possibilities for home automation and con-
  struction. The chief idea man for the Dutch House of the Future
  explains its underlying concept simply:
  "Think of it as a platform for exploring home life in the year 2000," says Titulaer, the author of more than 50 books on topics ranging from artificial intelligence to space research. "The house anticipates rapidly changing social attitudes and developing technology." Which, I suppose, explains its cylindrical glass-enclosed bathroom--including a translucent tub with underwater lighting.  
  "It's unlikely that the family home of the future will resemble our project," Titulaer admits, "but it generates ideas that may well carry over."

* T

[TOTO] (Japanese company web page) US subsidiary

This is the website of TOTO company that provided the special toilet in the TRON Intelligent House.

[TRON1994] Status Overview of the application subprojects of TRON Project in 1994 (in Japanese)

In particular [TRON1994b] TRON Intelligent House (in Japanese)

This contains a very detailed view of the TRON Intelligent House by the project members (the submitter of this application thinks so). And it is very important to understand their view back then. So its English Translation of the above web page is in Appendix IX.

[TRON1994c] TRON Intelligent City (in Japanese)

NOTE/CAUTION: the above web page uses JavaScript, and you have to select various entries by first selecting the following entries from the index page. (If you are reading a web page of an individual project, the link to the index page is at the bottom of the web page).

   Index Entry      The content
   はじめに          -> Introduction
   TRON電脳住宅      -> TRON Intelligent House
   トロン電脳ビル     -> TRON Intelligent Building
   トロン電脳都市     -> TRON Intelligent City
   トロン電脳自動車網  -> TRON-based Autotraffic Information Systems
   参考文献           -> References.

The description of TRON Intelligent House is very interesting read, and thus English translation is given in Appendix IX.

The *almost* complete list of introductory and enlightenment books written by Sakamura can be found in Introduction part and is quoted below. Only the Japanese titles are shown to convey the volume of the writing back in the 1980s. It turns out it did not include [SAKA1982], for example. Maybe [SAKA1982] was deemed too primitive. The list somehow missed [SAKA1987i] and [SAKA1988c], too. The list include books for general audience. They helped the eventual acceptance of the vision of TRON Project, namely HFDS, by many researchers and enterprises later.

   電脳社会論 /飛鳥新社
   コンピュータの時代1 トロンへの道程 /角川書店
   コンピュータの時代3 電脳未来論 /角川書店
   新版TRONで変わるコンピュータ /日本実業出版社
   TRONからの発想 /岩波書店 
   新版電脳都市 /岩波書店  [SAKA1987g]
   快適生活の技術 /光文社 
   マンガトロン /ごま書房
   トロン革命 /ソフトバンク
   コンピュータアーキテクチャ 電脳建築学 /共立出版
   電脳激動 /日刊工業新聞社
   BTRONへの招待 /パーソナルメディア
   コンピュータ未来館 /日本放送出版協会 

[TRON2024] TRON Forum website,
The above website is the focal point of the current TRON Project activities.

Detailed explanation of TRON Project is given in Appendix VII.

[SYDN2003] Japanese software guru doesn't envy Gates's riches
The Sydney Morning Herald, July 21, 2003.
Available online at:

This article relates the aftermath of USTR's naming BTRON OS as potential trade barrier very well.

Submitter's note: There is a somewhat inaccurate description about the TRON Project. The newspaper article may give the reader the impression that TRON Project was government one. It is not. Please bear in mind that the government plan to use the BTRON OS software (which was simply called TRON in the article, which is quite confusing), and the TRON Project which has been an academia-industry consortium are two separate things although there *ARE* government lab members in TRON Project.

* U

[UESH1991] Y. Ueshima et al., A fundamental study on picture motion TAD on BTRON specification operating system, Proceedings Eighth TRON Project Symposium, Year: 1991


  This study is aimed at specifying the TRON application data-bus (TAD) that handles digitized picture motion data based on real-time TAD. This TAD is called picture motion TAD. A conceptual model of a digitized picture motion and the basic structure of picture motion TAD are proposed. In real-time TAD, real-time data is represented as strings of events which occur in multiple output devices in parallel. The concepts of events and output devices in picture motion TAD are clarified by a multiplane model of digitized picture motion that represents the modification and composition processes.

[UROP2024] Open Smart UR Study Group (in Japanese)

This is a web page of on-going smart house project.

* V

* W

[WATA1990] Teresa Watanabe, House of Controversy : Technology: A new computer standard automates the TRON home with 1,000 microprocessors. Some American firms, however, are leery of Japanese intentions. July 2, 1990, LA Times
Available online at:

Interesting negative comment quoted in the article. It shows that predicting the future is difficult indeed.:

  The TRON house looks to me like an electronic whiz kid’s dream. It’s like the 1938 World’s Fair vision of the future,” said Gib Hoxie, a senior consultant with the Los Angeles office of Arthur D. Little, a technology consulting firm.
  He said consumers are already disgruntled with digital videocassette recorders and microwave ovens. They find dials easier to use and are moving toward them again.
  “TRON isn’t addressing that at all. They say, ‘Let’s pull all of this together in a universal digital interface.’ That’s a nightmare to me. It means I can’t run anything in my house,” Hoxie said. After some research last fall, he concluded that TRON “would be of no lasting significance” in the computer market, and he no longer follows it closely.

Submitter's comment: Mr. Gib Hoxie might have changed his opinion if he had visited the TRON Intelligent House as the reporter for Popular Science did. Also, what would he think of today's smartphones?

[WATA1991] Yoshimi Watanabe: “Home Bus System”, Vol. 45, No. 1, pp.40-47, 1991. テレビジョン学会誌 (The Journal of the Institute of Television Engineers of Japan)

This is a survey of home bus standardization efforts back in 1990.

Abstract/Forewords (Translated from Japanese)

  The great wave of advanced informatization is not limited to companies, but has begun to settle in homes with the use of advanced databases and information communication devices. The informatization of the home is called "home automation" or "intelligent house," and it is hoped to realize a system that provides a safe and comfortable home life and spiritual enrichment. The Home Bus System Standard, which will serve as the backbone of such a system, has been established. This paper provides an overview of this standard and overseas trends.

Note the use of "intelligent house" above. It is definitely influenced by the "TRON Intelligent House" name. But the grand scheme of HFDS did not seem to be understood very well yet because it was only mentioned in parallel with "home automation". HFDS goes much further to cover all aspects of the society which uses computers.

Original Japanese:

  高度情報化の大きな波は企業にとどまらず, 高度なデータベースの利用や情報通信機器が家庭に 定着しはじめた. 家庭の情報化はホームオートメーションとかインテリジェントハウスと呼ばれ, 安全快適な家庭生活と,心の豊かさを提供するシステムの実現が望まれている.その基幹となるホームバスシステム規格が制定された.この規格の概要と海外の動向について解説する. 

[WEIS1991] Mark Weiser, The Computer for the 21st Century, Scientific American, September 1991, Vol 265, Issue 3.

  Specialized elements of hardware and software, connected by wires, radio waves and infrared, will be so ubiquitous that no one will notice their presence.

A copy is available online at:

This article disseminate the term "Ubiquitous Computing" to the world.

[WIKI電脳] 電脳住宅 wiki entry in Japanese

TRON Intelligent House was called TRON電脳住宅 in Japan.

[WIND30] Windows 3.0, Wikipedia
Available online:
It has enough references.

"Windows 3.0 is the third major release of Microsoft Windows, launched in 1990."

This came after the TRON Intelligent House was built in 1989.

* X

* Y

[YAMA2024] Active Field Control (Online web page of YAMAHA)
This web page of YAMAHA explains the so called Active Field Control, the modernized version of the acoustic field creation system implemented in the TRON Intelligent House.

Translation of the first paragraph by the submitter.:

  AFC (Active Field Control): Sound Field Support System
  AFC (Active Field Control) is a system that uses the latest electroacoustic and signal processing technology to naturally change the auditory impression of architectural acoustics, such as room resonance, spatial expansion, and volume impression. The optimum length of a room's resonance depends on the type of performance being held. For example, for classical music, a space with resonance that enriches the musical sound is suitable, while a space with little resonance is suitable for a theater or a lecture.

AFC was developed as an acoustic design tool about 30 years ago to meet the needs of customers who wanted to hold various types of performances in a single space, and has been improved in various ways up to the present day.

Original Japanese from the web page:

  AFC(Active Field Control):音場支援システム
  AFC(Active Field Control)とは、最新の電気音響・信号処理技術を用いて、室内の響きや空間の拡がり・音量感などの建築音響の聴感印象を、自然に変化させることができるシステムです。室内の最適な響きの長さは、行われる演目によって異なります。例えばクラシック音楽には、楽音を豊かにする響きのある空間が適しており、演劇や講演会には、響きの少ない明瞭な空間が適しています。

The figure available on the web page, quoted below explains basically the same principle of the system which was used in the TRON Intelligent House, and thus we see a similar diagram in [YOUT-1].:

YAMAHA afc image02.jpg
The YAMAHA web page says YAMAHA developed this AFC as an acoustic design tool about 30 years ago. But since the submitter does not know how old this web page is, it might as well have been made available soon after TRON Intelligent House was built.

This is an overview of the first TRON Intelligent House.

   00:40 Natural and simple design
         Communication among family members
   01:14 Indoor garden and semi open space
   01:22 Windows open automatically
   01:34 Leaving the house button
   01:43 Air flows from the rooftop
   01:58 Intelligent kitchen
   02:28 Cooking support system
   03:00 Japanese bath
   03:14 Switches in the bathroom follow the design guideline
   03:27 Electrically controlled transparent glass
   03:40 Bathroom vanity
   04:03 Toilet on the first floor
   04:21 Toilet on the second floor (medical check)
   04:53 Party cart (movable sink)
   05:13 Lighting (hidden and adjustable)
   05:44 Dim footlight turned on automatically
   05:55 Air conditioning in the living room
   06:27 Temperature sensors (and airflow monitor)
   06:48 Acoustic field creation
   07:23 Sensors are placed discreetly. Opening windows and controlling lighting.
   07:53 Growing plants in indoor garden
   08:33 Computerized storage system

Title: [2011-09] TRON Intelligent House

This video looks at the TRON Intelligent House project including the first TRON Intelligent House in Tokyo in 1989, TOYOTA: PAPI (v2) in 2004, and Taiwan u-home (2009).

  00:00 TRON Intelligent House history, the first one, PAPI, u-home,
  01:00 TOYOTA PAPI: SDGs energy-efficiency, wall/windows maintenance free
  01:40 Context Awareness (the first TRON Intelligent House in 1989)
  02:01 Context Awareness (u-home)
  02:10 waking up occupants at the right time.
  02:26 PAPI
  02:40 connected devices, toilet in the first TRON Intelligent House
  02:58 wristwatch-like monitor device
  03:13 Future refrigerator PAPI
  03:31 automatic storage system (the first house)
  03:42 self-playing electric piano (PAPI)

[YOUT-3]video 3 u-home
This is an overview of Taipei u-home.

  00:00 2009 Taipei u-home
  Comfortable living space, low-energy cost, reasonable construction cost
  (for more wider adoption of smart houses)
  00:39  Tropical Plant on the wall
  The unit to grow plant in this manner has evolved from the first TRON Intelligent House in 1989.
  00:49  Recognition of residents’ whereabout
  lighting is 99% by LED lamps (u-home was built in 2009).
  01:09  Power Usage awareness
  This alone encourages the efficient energy usage of the residents.
  01:35 UC terminal helps residents talk to the networked devices via universal virtual switches
  Please recall that Apple i-Phone appeared in 2007 (and u-home was completed in 2009).
  Lighting, opening curtains, playing BGM
  02:18 delivery arrivals with security consideration
  02:54 bathroom with smart functions
  03:03 RFID usage in u-home
  u-code tags
  03:17 toilet (u-home)

* Z



The second TRON Intelligent House TOYOTA PAPI was completed in 2004. It inherited the experience and knowledge of the first TRON Intelligent House and subsequent research and development activities.

For PAPI, LAN replaced the serial wiring of the first TRON Intelligent House. The following photo shows the change. Maintenance became much easier.


Also, the computer power increased, and computer board became much smaller. Thus basically, all the server-related functions could now be handled by computers inside the wall. We no longer had a big server room or space as in the first TRON Intelligent House.


Photo: Courtesy of Ken Sakamura

RFID technology was used widely in this house. Also, a smartphone-like device called Ubiquitous Communicator (UC) built around that time was used for control purposes.[UC is explained later.] UC had appeared a few years before Apple iPhone. iPhone was announced in January 2007, and was sold in June 2007 in the USA.

For PAPI, TOYOTA Housing and other project partners developed novel technologies aside from computers: For energy efficiency, PAPI used solar batteries that were thin coating on the window glass(Dye-sensitized Solar Cells on p. 126 of [A+U2005]), fuel cells (Residential Fuel Cells, p 131 of [A+U2005], and took advantage of TOYOTA's hybrid car, Prius, as emergency backup to make the smart house operate when there is a black out of electricity outside.

TOYOTA PAPI achieved the following features which were later commercialized.

  • Smartphone and the control of house facilities by it
  • Healthcare by wireless wrist-band sensor
  • Facility control using natural voice recognition
  • HEMS (Home Energy Management System)
  • Power generation by plug-in hybrid car
  • Fuel cell for home use
  • Dye sensitized solar cell
  • Photocatalyst self-cleaning outer wall
  • LED display for housing
  • BGM that follows people's movement
  • Use of wireless markers for indoor positioning

Some features of TOYOTA PAPI are explained below.

Maintenance free

TOYOTA PAPI featured maintenance free windows and exterior walls. Windowpanes were self-cleaning using optical catalytic material to wash away dirt when it rained. VIDEO: [YOUT-2]

This feature is an extension of the bathroom sink of the first TRON Intelligent House. It also had self-cleaning surface. This time, PAPI extended the use to the external walls and glass windows of the total house.

Intelligent Refrigerator

The refrigerator knew what was inside, and it could tell the residents when a food item would go bad based on the expiration date.

Such approach was made possible by the extensive use of barcode technologies in the food distribution network and the wide availability of RFID technology so that the scanning of items allowed the refrigerator to recognize the food item and access database to learn its expiration data. VIDEO: [YOUT-2]

Comfortable living: waking up people at the right time.

The house woke up residents at the most comfortable moment by monitoring sleep of residents. VIDEO: [YOUT-2]

Wristwatch-like sensors

It is common to see people walking with medical sensors built into wristwatch-like devices in 2024.

Such wristwatch-like device had to be built from scratch for TOYOTA PAPI. Blood pressure and heart beats could be monitored, and an emergency signal could be generated, and a call could be made to a nearby hospital if there were anomalies.

Music play

On top of the acoustic creation system, an electric piano was installed, and it could play a melody according to a master’s arrangement when a futuristic concert-ticket is scanned. VIDEO: [YOUT-2]

Improved Storage system and assisted kitchen.

Intelligent Storage and computer assisted kitchen modeled after the that of the first TRON Intelligent House were created using more advanced technology. For example, the advanced affordable CCD image sensor used in digital camera could be used for Intelligent Storage system, and display screens were thin LCD screens by then instead of the bulky CRT monitors used in the first TRON Intelligent House. (p. 84, Intelligent Storage System in [A+U2005]).

The advent of IT technologies was reflected in the second TRON Intelligent House, PAPI.

The project adopted newer technologies and built on the lessons learned from the early project this way.

Ubiquitous Communicator

To show that the lesson learned from the first TRON Intelligent House was reflected in later projects, let us explain why a device called Ubiquitous Communicator was created for the second TRON Intelligent House, PAPI. [p. 72, Ubiquitous Communicator, of [A+U2005]

English caption:

  Above: Ubiquitous communicator: a communication device equipped
  with diverse communication modes such as wireless LAN, RFID
  reader/writer and infrared communication, and diverse HMI modes such
  as sound, video, touch panel, buttons, and fingerprint scanner: A
  person will carry one such device at all times. An advanced form of
  the present-day cell phone, this satisfies all communication
  demands from conversations with an intelligent house, such as
  giving directions to mechanical systems and receiving reports from
  mechanical systems to conversations with other occupants as well as
  the outside world.

No switches on the wall: Why UC was created

Toyota PAPI did NOT have switches on the wall at all. Instead UC terminal acted as hand-held versatile device to control objects such as lighting, audio visual display, etc. Even though the efforts were made to standardize the switches in the first TRON Intelligent House to decrease the confusion on the side of users, there were limit. Mere switches could not offer the many user interfaces necessary for advanced devices in the 21st century. So UC with a small LCD screen acted like today's smartphone to offer versatile user interface.

The feedback from the first TRON Intelligent House resulted in the development of UC as replacement, and the radical approach of eliminating physical switches on the wall. This pushed the envelope of the technology, so to speak.

Appendix II: Taipei u-home

Here are some features for Taipei u-home that was completed in 2009.

u-home's three main features were achieved using then available IoT technology.

  • comfort of living
  • energy efficiency
  • lowering the cost of maintenance

Another objective of u-home to show that such a smart house could be built using then available technology at reasonable price.

An overview of u-home is available as a short video on YouTube, [YOUT-3]:

There is also a PDF brochure that explains Taipei u-home. Interested readers are referred to it. File:U-home-brochure.pdf

TLD would later build a larger residential building in Hualian (花蓮) in 2011.

Greenery was used widely for comfort.

The indoor plant support system used there is a newer version of such system from a different company from the one that supplied similar system in the first TRON Intelligent House. Such a system had become common in the 20 years since the first TRON Intelligent House.

Energy efficiency

LED lamps were used exclusively for illumination. Also, every use of electricity was visualized in the ubiquitous communicator terminal and this affect residents psychologically to keep energy use down.

Appendix III: TRON Intelligent Building

TRON Intelligent Building project as an application subproject of TRON Project is explained in [SAKA1991b] and [TRON1994c]. This subproject was started in May 1989 while the first TRON Intelligent House completed in December 1989 was still under construction.

From [SAKA1991b]:

  2.2 TRON-concept Intelligent Building Research Group
  Prototype construction of next-generation office buildings and
  development of software for near-future offices are goals of the
  intelligent building project, started in May 1989. The 12 members are
  construction firms and makers of building materials, including Hazama
  Corporation.  Preparations are now under way for actual construction
  of the first building, in the Aoyama-Harajuku part of Tokyo.  (Photo

The translation of the first paragraph of [TRON1994c]: From [SAKA1994c]:
Choose "TRON電脳ビル" from the index. (If you are reading a web page of an individual project, the link to the index page is at the bottom of the web page).

  The TRON Intelligent Building” provides comfortable and lively offices that are "people-centered" and "worker-centered" based on the main concept of "motivating offices. The building is organically arranged with open offices for work requiring communication, private rooms for concentration, a rooftop garden and semi-outdoor terrace for change of mood, and a refreshment zone.
  A decentralized supply chain management system provides support for material management, with robots delivering necessary documents and other items, and storing them for safekeeping. They also deliver drinks to the location of each person.
  Super ID cards allow the building to recognize who is where , so that phone calls and information can be transmitted instantly, no matter where they are.
  The building also includes an analyzer/compiler system that analyzes the movements of workers and suggests the best floor layout for their work, advanced sound and lighting control systems, highly functional conference rooms, and a security system.
  The TRON Intelligent Building is positioned as a model for office space in the 21st century, and the goal is to move from a stand-alone building to a TRON Intelligent City in the future, using the TRON network.

Please note that this was written circa 1994 before the smartphone became popular.

Appendix IV: TRON Intelligent City

From [SAKA1991b]:

  2.3 Chiba TRON Computer City Study Group
  The Computer City project is planning and developing
  an entire city complex, in which intelligent houses, buildings,
  traffic and other systems are all brought together. This
  ultimate in application projects will link countless intelligent
  objects and communication machines in a true HFDS .
  The project began in May 1989. There are 47 members,
  including special members like Chiba Prefecture. The construction
  site is a 250-acre plot in Ichihara, Chiba. Development
  work is expected to continue into the next century.
  (Photo 4)

From [SAKA1994c]: Choose "TRON電脳都市" from the index.
(If you are reading a web page of an individual project, the link to the index page is at the bottom of the web page).

  TRON Project aims to establish the fundamental technologies necessary for a "Computing Everywhere" society - a future society in which computers will be embedded in various "objects" around us and will support all aspects of our lives while being connected to and cooperating with each other via networks. - The project aims to establish the basic technology necessary for a future society in which computers will be embedded in various "objects" around us, connected to each other by networks, and operating in concert to support all aspects of our lives.
  For this purpose, we have proposed and are conducting research, development, and experiments on TRON Intelligent House, which incorporates 1,000 computers, and on a larger scale, TRON Intelligent Building. As the largest application of this "Computing Everywhere" environment, we are conducting research on the application of computers in urban areas. This is the TRON Intelligent City (TRON 電脳都市) Project .
  As a specific case study, for about two years starting in 1989, a research activity was conducted on integrating information systems at all levels by applying TRON concepts to urban infrastructure and urban intelligence (in 2024 parlance, smart city)  in a hilly area of about 300 hectares centered on Ichihara City in the central part of Chiba Prefecture (Chiba TRON Intelligent City, 千葉トロン電脳都市).
  Currently, for the construction of a "human-friendly" intelligent city, we are working on guidelines for various components of the city, including the institutional structure, with a focus on human interfaces and information infrastructure.
  The following is the basic concept of Chiba TRON Dennen Toshi and the functions to be introduced. ...
  [rest is omitted.]

There are a couple of nice drawings of the then planned cityscape in the web page.

The vision of HFDS is clearly demonstrated in this subproject of TRON Project.

Appendix V: TRON-Based Autotraffic Information System

TRON-Based Autotraffic Information System as an application subproject of TRON Project is explained in [SAKA1991b] and [TRON1994c]. This subproject was started in November 1989 while the first TRON Intelligent House was about to be completed in December 1989.

This is about the intelligent network for automobiles of the future (as envisioned by TRON Project in the 1980s.)

From [SAKA1991b]:

  2.4 Technical Committee on the TRON-Based Autotraffic
  Information System
  Major automakers have banded with electronics firms to
  design the concepts of future automobiles, and of traffic
  systems that will allow information to be exchanged among
  cars, roads, and cities.
  This group was formed in November 1989 , and comprises
  13 firms. Presently the members are drawing up
  HMI specifications for automobiles based on TRON Project
  design guidelines, and also data standards for electronic
  cards that will be used with automobiles. Continuing studies
  will focus on patterns of cooperative action applicable
  to intelligent cars and computerized traffic systems, and
  also on data standards for communication between cars and
  road systems.

From [SAKA1994c]: Choose "TRON電脳自動車網" from the index.
(If you are reading a web page of an individual project, the link to the index page is at the bottom of the web page).

English translation of the first section:

  The TRON Research Committee for the TRON-based Autotraffic Information Systems was established in November 1989, bringing together the automotive, electrical, and construction industries to build the automobile and automotive transportation network in the future cyber society. TRON-Based Autotraffic Information System is an "automobile network of the future" in which automobiles use computers to exchange information not only with other vehicles but also with roads and cities in a coordinated manner, making automobile operation safer and more comfortable.
  TRON application projects include Intelligent House, Intelligent Building, and Intelligent City, etc. In the coming TRON Intelligent Society, automobiles will be integrated into the network and function within that society. In the TRON-Based Autotraffic Information System, automobiles will use computers to cooperatively exchange information not only with other automobiles but also with roads and cities to make automobile operation safe, comfortable, and efficient. This study group was a time-limited study group for three years, which ended in December 1992.

The vision of HFDS is clearly demonstrated in this subproject of TRON Project and precedes today's automobile network concept by many years.

Appendix VI: Publication about the TRON Project

The article published in 1996, [SAKA1996], lists almost all the major publication related to TRON Project, including TRON Intelligent House, and HFDS in the period (1984-1996). Most of the references are found in this list.

  • Proceedings of Annual Symposiums
  • - TRON Project 1987-1990
  • - Proceedings of the TRON Project International Symposium, 1991-1996

"TRON Project 1987, 1988, 1989, and 1990” and “Proceedings of the TRON Project International Symposium, 1991, 1992, 1993, and 1994” are the proceedings of the TRON Project International Symposium, which is a conference on purely technical/scientific content. The symposium is annually held. The proceedings of the TRON Symposium were published by Springer Verlag initially. Since 1991, the symposium has been held in cooperation with IEEE Computer Society and the proceedings have been published from the IEEE Computer Society Press.

All the proceedings of TRON symposiums available in IEEE Xplore can be searched using the following URL.

In a nutshell, IEEE Computer Society press published the proceedings from 1991 to 1996. Then TRON Project stopped publishing the proceedings since the emerging web was deemed good enough for disseminating the technical result of the project. However, it again has begun publishing the proceedings of the symposium now co-sponsored by then IEEE Consumer Electronics Society, now Consumer Technology Society since 2014 until today (the last conference was in 2023 and it is going to be held in December 2024 again).

Appendix VII: INIAD HUB-1, an IoT university campus building

INIAD HUB-1 is a building on the campus of Faculty of Information Networking for Innovation And Design (INIAD), Toyo University in Tokyo. Sakamura is the dean today. It was completed in April 2017. It is based on the concept of the IoT fully. This is based on the philosophy of TRON Project. The building itself is the testbed for the IoT for research and education. [INIA2024]

6LowPAN is used widely to connect sensors and actuators on top of Wi-Fi and Bluetooth. These were not available back in the days of the first TRON Intelligent House in 1989.

The Internet is now used fully, and some control functions now reside in the clouds. The home server of the first TRON Intelligent House is no more.

The following photo shows the technology change between the first TRON Intelligent House (v1), TOYOTA PAPI (v2), and INIAD HUB-1. The necessary computers have become much smaller, and wiring disappeared. The small computer board next to a fan in the photo talks to 6LowPAN and gets command from the control program in the cloud.

KEN-分散かと機能外部化.jpg Photo: Courtesy of Ken Sakamura

Many parts of the ceiling of the INIAD HUB-1 are simply covered by metal mesh. This makes it easy to install 6LowPAN border routers, projectors, etc. for research activities. This mesh is reminiscent of the first TRON Intelligent House where wooden mesh covered the ceiling in which lighting fixtures were installed.

Photo from [INIA2024]

Here is the explanation of INIAD HUB-1 from [INIA2024].

English Translation of the description in the above web page.

  IoT-enabled campus of the future
  Learning in a state-of-the-art space
  The INIAD at Akabanedai Campus uses innovative IoT technology to connect various facilities and equipment to computer network, which then operate in concert according to the conditions of the campus to provide an optimal environment for people and to optimize the energy usage. This concept of optimally controlling facilities and equipment according to the conditions of the space is the goal of the TRON Project, for which Dean Ken Sakamura is the project leader, and the Akabanedai Campus is a future campus that incorporates the results of this research.
  There are no light or air conditioner switches in the laboratories. The environment is automatically recognized and controlled using environment sensors on campus, and instructions from users are given via the campus computer network from smartphones or PCs. Users enter and exit classrooms and laboratories by unlocking them with IC cards or smart phones. Information on lectures and other announcements can be found on digital signage and smartphones installed on campus.
  Network environment suitable for computer education
  The campus is equipped with Wi-Fi and has sufficient Internet access bandwidth for education, allowing students to bring their own PCs and smartphones for use in classes and research.
  In addition, the INIAD Education Cloud is provided as a cloud
  computing environment. Many lectures are available using the INIAD
  Education Cloud. The INIAD Education Cloud is also equipped for
  students to use it for their own learning and research, and the
  operation staff is available to assist students when they have
  The entire building is the learning material of the IoT
  In INIAD HUB-1, various facilities, equipment and devices such as sensors, lighting, air conditioning, lockers, and elevators are directly connected to the cloud, and can be operated through an API (Application Programming Interface, which defines a protocol used by computer programs to obtain information from and control other programs and equipment). The equipment can be operated through an API (Application Programming Interface, which defines a set of commitments from a computer program to retrieve and control information from other programs and devices). At INIAD, we are taking advantage of the small class size to actively develop courses that use these APIs. By learning the APIs and programming to operate them, students can control this IoT-enabled smart campus as they wish, within the limits of the access privileges assigned to them.
  For example, let's say that a student is given an assignment to write a program to repeatedly turn the lighting to  FULL (bright)/DIM (dim)/OFF (off) state. The students would write the program using the INIAD API. Then, using the classroom projector, each student's screen would be projected, and the API would be immediately executed and presented. They are also taught to mash up the INIAD API with APIs from various external services to develop more advanced applications. For example, a program that controls the lighting in a room by saying "please turn on the lights" or "please turn off the lights" can be realized by mashing up the APIs of voice recognition services provided by Google and INIAD's API.
  In this way, INIAD students will acquire the knowledge necessary for the IoT era, in line with the concept of open APIs.

Example of INIAD Campus API usage

     Automatic blinds are lowered, and lighting is turned on when outdoor
  sunshine interferes during a presentation in a room.
     When a person enters a room by holding up an IC card, the
  illumination and air conditioning will operate according to the
  preferences of the person entering the room.
     If the floor to be used and the destination floor are entered into
  the smartphone in advance, the elevator can be automatically
  controlled to move to the destination floor simply by going in
  front of the elevator, even when both hands are occupied carrying
  Intelligent Locker
     The surface of the Intelligent Locker has a simple design with
  no nameplate. There are only plain rows and columns of
  panels. These panels, or each locker door, can be opened by IoT
  control. The IC card for transportation payment is used to open the
  locker door. The train commuter pass serves as the key to the
     The intelligent lockers are also used as educational materials
  for students. Students will be able to use their own lockers for
  the first time by linking the door to their smart phones and IC
  cards through programming. As students learn more, they can, for
  example, send an electronic key by e-mail to a friend who has given
  them permission to open the door only once.
     The intelligent lockers are also used as educational materials
  for students. Students will be able to use their own lockers for
  the first time by linking the door to their smart phones and IC
  cards through programming. As students learn more, they can, for
  example, send an electronic key by e-mail to a friend who has given
  them permission to open the door only once.
  Digital Signage
     INIAD's paperless policy means that there no blackboards or
  whiteboards in the classrooms, and there are no bulletin boards to
  put up paper. For this reason, a number of digital signage systems
  have been installed throughout the INIAD HUB-1. Of course,
  information can be obtained from smartphones or computers, but
  digital signage is the most effective way to disseminate
  information. The main digital signage is a 55-inch touch panel
  display. The display content changes always. But it stops when
  touched, allowing visitors to find the information they need, read
  it on the spot, and import it to their smartphones or other
  devices. In addition, there are a number of projectors for wall
  projection, making it easy to disseminate information within the

Appendix VIII: Introduction to TRON Project with its goal of HFDS

This is a slightly edited version of TRON Project description in the IEEE Milestone application for “TRON Real-time Operating System Family, 1984”.

  TRON Project:
  Here is a brief historical background of the TRON Project which
  produced the TRON RTOS family, another IEEE Milestone, and the TRON
  Intelligent House. In the late 1970s, Ken Sakamura recognized the
  potential of the microprocessors as the infrastructure of the
  future society in the 1990s. However, he and his team identified
  several problems with regard to the use of microprocessors in the
  early 1980s. He started a computer architecture project to solve
  such identified problems in 1984.
  The project is called TRON Project. He has been its leader since then.
  TRON Project formed the TRON Intelligent House Study Group
  (tentative English name) and that group created the TRON
  Intelligent House under the leadership of Sakamura.

Note: In some public speeches or commercial trade press articles, the project name, TRON, is used to refer to the popular TRON RTOS family. The distinction is subtle, but the readers are cautioned not to mix these two different concepts.

  One of the goals of TRON Project has been to design and standardize OPEN and FREE computer architecture for the embedded systems. The ultimate goal of the project is, in today’s technical terms, the full deployment of the IoT and related services in the society to better our living environment. The service created by IoT edge nodes and cloud services was referred to as HFDS (Highly Functionally Distributed System) in the vision of TRON Project [SAKA1987].
  cf. A figure of the concept of HFDS from page 7 of paper [SAKA1987]
  is quoted elsewhere in this Milestone application.
  Sakamura has chaired two Non-Profit-Organizations (NPOs), TRON
  Association and TRON Forum. The latter has absorbed TRON
  Association since 2010, that had been created to support TRON
  Project by publishing technical specifications, offering the
  communication channel among its members and held annual symposiums
  and accompanying exhibitions.
  Supporting Non-Profit Organizations of TRON Project:
  It is important to note that there have been NPOs to support the
  project as the organization to publish the technical
  specifications, to offer technical seminars to train people, to
  help organize the annual technological symposium with accompanying
  exhibition called TRON Symposium (TRONSHOW), and to hold the
  special symposium called TRON Enableware Symposium to help the
  physically challenged or disabled people by the use of
  computers. (This was an important goal of the second TRON
  Intelligent House, TOYOTA PAPI. By then, people know we can build
  so-called smart houses. But for what? PAPI paid attention to
  Enableware topics.)
  The current NPO is called TRON Forum. The TRON Symposium (TRONSHOW)
  has been held 38 times and technically supported by IEEE Consumer
  Technology Society since 2016 so far. It was technically supported
  by IEEE Computer Society from 1991 to 1996.  TRON Symposium
  (TRONSHOW) website,],

Appendix IX: TRON Intelligent House description in [TRON1994c]

The Museum of The University of Tokyo web page has an interesting description of the TRON Intelligent House.[TRON1994c] It was written in circa 1994, and sums up the house very well. It does not mention IoT since the world has not caught up with the HFDS notion very much yet and the phrase, the IoT and for that matter, "ubiquitous computing" took at least another year or two to become popular in the IT industry and it took more to become common.

Here is an English translation of the page content for reader's reference.

  TRON Intelligent House
  The TRON Intelligent House is a housing project that embodies the philosophy of TRON Project which envisions "a future society in which computers will be used by ordinary people in all aspects of their daily lives, not just by a few specialists," and which addresses a wide range of themes, including devices and systems that anyone can use, the concept of future life to be realized through new technologies, and the social structures and rules that support this concept., and which tries to  create a total design that addresses these issues head-on.
  TRON Intelligent House Study Group was established by 18 private
  sector companies that agreed with this idea, and they built TRON
  Intelligent House which was completed in December 1989 for a
  private sector experiment for the realization of true home
  In April 1990, a portion of the pilot house was opened to the
  public, attracting a total of 10,000 visitors. including the Crown
  Prince of the Netherlands, the Swedish Minister of Construction,
  and many other prominent figures from Japan and abroad. Many
  broadcasters, newspapers, and magazines, including the BBC and CNN,
  also visited the site to cover the event, which was widely
  After that, the study group suspended the open house and conducted
  experiments to verify the operability and comfortableness of the
  system by actually having people live in it, pursuing the comfort
  of "true home automation" houses, future lifestyles, and the
  possibilities of new design methods. After five years of research,
  the study group was terminated in January 1993.  Although the terms
  "intelligent house" and "home automation" have been used for a long
  time, most of them were simply a collection of disparate devices,
  not a total proposal. In addition, recent home appliances are
  becoming increasingly sophisticated, but the operating methods for
  using the abundant functions are becoming more complicated. The
  TRON Intelligent House, on the other hand, has a simplified
  appearance despite its high functionality, thanks to the
  unification of operating methods and the simplification of
  instructions by means of coordinated operation.
  Basic Concept
  Embodying the TRON Project philosophy in housing The TRON Project's
  philosophy is to seek the ideals of the society to come, without
  being bound by the constraints of reality, and to consider what
  should be started now, rather than later. The "TRON Intelligent
  House" also began with a dream of living style as it would be in
  the near future. The "TRON Pilot House" is a "Pilot House" where
  people can actually experience living style of the future.
  "TRON Intelligent House" proposes the true potential of "Intelligent House"
  A house is a place where various people live safely, conveniently,
  and comfortably. As lifestyles become more diverse and society
  becomes more information-oriented, the requirements for housing are
  becoming more complex. Therefore, a system that integrates and
  finely adjusts various functions and that can be used by anyone is
  needed. The goal is to create a "true intelligent house" that is
  highly functional, flexible, and sophisticated.
  The "TRON Intelligent House" pursues a total design that transcends industry barriers
  A house is the stage for all aspects of life, and it must be richly
  inclusive and harmonious. Comprehensive planning of buildings and
  facilities, coordination of space and interior design, and harmony
  between high functionality and a living environment that is
  compatible with Japanese sensibilities are the key elements of the
  TRON Intelligent House. The ideal total design is made possible by
  the unprecedented collaboration of companies from different
  housing-related industries in the construction of a single
  experimental house.
  The "TRON Intelligent House" is a new approach to spatial design.
  The installation of a semi-outdoor space allows residents to live
  with wind, light, and plants. The introduction of an automated
  warehouse allows for a home that is not bound by preconceived
  notions of storage space. The holistic design harmonizes natural
  materials, equipment, and computers. A house that protects healthy
  and safe living style through an intelligent system. The search for
  new functions begins with a scenario of a new way of living. Then,
  by qualitatively changing the function, a new spatial design
  becomes possible.
  Each device in the TRON Intelligent House operates autonomously and
  transmits information to other devices through the network, such as
  collected information and operational status. In addition, each
  device controls its operational status based on the information
  that flows to it as needed. The format of the information that
  flows in this manner is called TAD (TRON Application
  Databus). Therefore, the method of cooperative behavior is defined
  by how this information is taken in and used. The residents'
  impressions will differ depending on how this cooperative behavior
  is performed.
  In order to find out what kind of impression residents have of the
  TRON Intelligent House, what kind of cooperative behavior should be
  performed, and what features are perceived differently by
  individuals,  a trial occupancy experiment was conducted by
  volunteers of the TRON Intelligent House Study Group members.
  The overall impression and design of the house were generally highly evaluated. In particular, impressions of the interior, living room, semi-outdoor space, and bathroom were very high. In addition, many of the residents would like to return for another trial move-in.
  In addition, the in-home LAN and operation methods were examined. The results, especially with regard to the operation method, were reflected in the TRON Electronic Equipment HMI Study Group's "TRON
  computerized living HMI Specifications".

Above was English translation of the quote from [TRON1994c] ("TRON Intelligent House" written in 1994).

The original Japanese can be read by the following steps. Visit the web page.

The above web page seems to use JavaScript, and you have to select various entries by first selecting the following entries from the index page. (If you are reading a web page of an individual project, the link to the index page is at the bottom of the web page).

   Index Entry      The content
   はじめに          -> Introduction
   TRON電脳住宅      -> TRON Intelligent House
   トロン電脳ビル     -> TRON Intelligent Building  <--- THIS
   トロン電脳都市     -> TRON Intelligent City
   トロン電脳自動車網  -> TRON-based Autotraffic Information Systems
   参考文献           -> References.

The description of TRON Intelligent House is available on indexed page as "トロン電脳ビル".

Appendix X: Devices created for the TRON Intelligent House

Explanation of the devices that were created for the TRON Intelligent House by the member companies is given here.

Human motion sensors

High security main bank vaults and military installations had some form of human sensors back in the late 1980s. But there were NOT commercially available off the shelf human sensors that could be used in a commercial housing easily. So such sensors were built. They became commercial products years later.

Detection of resident was used in various ways. In a sleeping quarter, if someone woke up in the middle of the night and got out of bed, the motion sensor detected it and turned on foot light automatically in the TRON Intelligent House. (The footlight that turns on automatically after sensing human motion has been commercialized.)

When someone was near a window, the house tried not to use the window blind actuator since the person may be watching outside the window, and would be surprised if the window blind suddenly closed, for example. So human motion sensors were used to detect the presence of people, and the house incorporated the position of the people to disable the activation of window blind devices while the residents were nearby. Window blinds were automatically closed based on the day or the cold temperature outside.

Weather sensor: outdoor and indoor wind sensors

Wind sensors used outdoor are common. But for optimum passive air conditioning system used in the TRON Intelligent House, an air flow sensor was developed to monitor air flow in rooms (indoor anemometer).


A photo from [SAKA1990a]: Radiant cooler in the ceiling of the living room.
Japanese caption:

  Radiant cooler panel and a speaker for creating acoustic field 

The second floor of the house used fans for air conditioning and the speed of air flow was detected by these indoor anemometers and got adjusted.

Passive Air conditioning system: rain sensor

The TRON Intelligent House tried to cool the house with natural air flow as much as possible It opened windows when the outside temperature was about right and there was breeze outside. All the window panels of the house could be opened/closed via actuators controlled by computers.


  Photo from [A+U2005] Windows of the semi open space were all opened.
  Above: Roof on the south side of TRON Intelligent House Ver. 1: the
  central pyramid also automatically opens and closes. Below:
  Intelligent windows with an automatic opening/closing mechanism for
  covering the half-outdoor space: each pair of windows automatically
  opens and closes separately, depending on conditions such as wind
  direction. I believe a computerized house of the future is a matter
  not of design, but of function. I there made the house a simple,
  two-sided building, square in plan and made of natural
  materials. The exterior walls are stuccoed with a scratched finish,
  and the entrance is paved in Oya stone. The interior walls are made
  mainly of washi (Japanese, hand-molded paper), and wood materials
  which are also made principally of Japanese wood used in a natural

There is a short overview of how the windows were controlled in the video, [YOUT-1]:
The hot air and heat are released from the top of the roof.

The living room used floor heating and radiant cooling. Computer-controlled fans made the temperature gradient small to make the whole living quarter comfortable. For detailed explanation of the air conditioning, please see the video, [YOUT-1]:

The air flow inside rooms were monitored using small air flow sensor.

The whole house had many temperature and humidity sensors in the rooms and the house controlled air conditioning system accordingly to provide comfortable living space.

Toilet with medical sensor (blood pressure and urinalysis)

Popularity of Japan's famed shower toilet [TOTO: ] could be traced to this house. The manufacturer, TOTO was a member of the TRON Intelligent House Study Group. (it changed its name to TOTO in 2007.) Such toilet was marketed since the beginning of the 1980s. But it did not take off until about the year 1990. The publicity generated by the many general news in newspapers and TV news programs, and industry trade magazines that covered the TRON Intelligent House certainly helped its popularity.

In the house, you could operate the toilet without ever touching anything. Moving your hand over the sensors operated it. In the bathroom, you could watch TV and use a telephone (remember there was no smart phone in 1989). It is explained in the video [YOUT-1]:
The toilet on the second floor was special. It had a blood pressure sensor and urinalysis system. It could monitor the residents' health and the information was stored in an individual IC card. The data could be sent to external medical service via encrypted communication. (Remember, there was NO Commercial Internet connection back in 1989.)

The scaled down version without the medical checkup facilities has been sold commercially with great success. [TOTO] There are TOTO products and many similar products from other companies now.

Intelligent Storage system

Objects that are not used frequently could be stored in underground storage space. But finding where such objects had been stored was a hassle.

Photo from [NORM1990]

  An automated storage system takes bins from access parts in the
  living area through a shaft to the basement. A video camera in the
  ceiling can record either a still shot of the contents or a video
  of a bin being loaded. The image can be viewed on the monitor and a
  bin selected for retrieval using the control panel (inset).

There is an overview of the computerized storage system in the video, [YOUT-1]:
So a system was built to store objects in movable containers. The system records what was stored when into which container. (It was done by taking a digital photo of the container content using a camera on the ceiling.)

When an object was to be retrieved, the container that held the object was automatically moved to the front space so that the object could be easily picked up.

Intelligent kitchen

There were many elements in the so-called Intelligent Kitchen. (It is best explained by the video, [YOUT-1]: )


Kitchen heater: Photo from [SAKA1090a]
Japanese caption:

  Cooking table: Heaters (220V 6kw), fridge, freezer, water purifier,
  and water cooler are built in.
  It memorizes the steps for a recipe and automatically follow the
  steps for heating and the amount of seasonings. The
  computer-assisted cooking support system can recall the recipes by
  famous cooks of the world.

The listing of technology elements are listed in the following.

  • computer-controlled induction heater

FYI, Matsushita, today’s Panasonic, started to sell the first Induction Heater (IH) for kitchen in 1990.

  • computer-controlled oven
  • computer-controlled refrigerator
  • computer display
  • computer-controlled dispenser for seasonings
  • cooking assistant

There was a special cooking assistant system with computer display:

  • It could suggest menus based on available food ingredients
  • It played the video to show how best cooks in the world prepare particular dish, and the system dispenses the right amount of seasoning accordingly automatically
  • movable sink with water supply

There was also a movable party wagon. It could be moved and connected to water supply/drainage/electricity stations.


Photo from [SAKA1990a], courtesy of TRON Intelligent House Study Group
Japanese caption:

  Movable party wagon: It has connector for hot water supply from the
  floor station, mini sink, hot plate, and a fridge.
  The house has three stations for water supply/drainage and
  electricity and the wagon can be placed on one of them.

The overview of movable sink (part cart) is in the video, [YOUT-1]:

Japanese bath

Japanese Hinoki bathtub was installed to follow the Japanese tradition. But the novel feature of the TRON Intelligent House should not be overlooked.

Switches based on the TRON Human-Machine Interface Guideline

The operation of switches in the bathroom follows TRON Human-Machine Interface Guideline. This is a testament that the whole house was built with a guideline to offer uniform human machine interface. All other switches in the house followed the guideline, too. There was an effort to create de facto standards among the builders. The switches in the bathroom are explained briefly in the video, [YOUT-1]:

Glass window with electrically controlled transparency

This was to make the bathroom and other interior rooms look much more spacious when the glass became transparent. This was controlled by a switch or a computer. The action of the glass is explained in the video, [YOUT-1]: Such a glass panel is now common in hotels and other places

Faucet that changes its height via computer control

This was to make it easy to wash your hair there, for example. The sink was equipped with built-in shampoo and conditioner dispenser. The sink's surface was auto-cleaning type with catalytic material. It is explained briefly in the video, [YOUT-1]:

Acoustic field creation system

In the house, the audio system could mimic the audio environment of a big concert hall, small music studio, etc. The microphone installed on the ceiling picked up the sound and fed it to digital signal processing system to create an artificially created echo. This echo was fed to speakers on the ceiling to give the resident the acoustic feeling of a big concert hall, etc.
This acoustic field creation system was implemented by YAMAHA.

Such sound effect software was commercialized later. We have such a system in today's audio software on PCs.

The principle is explained briefly in the video, [YOUT-1]:


Photo from [SAKA1990a], speakers were on the ceiling.
Japanese caption:

  Radiant cooler panel and a speaker for creating acoustic field 

YAMAHA, responsible for the acoustic field creation in the TRON Intelligent House, has developed the technology to support the concert hall and other public places over the years and has been offering the technical support for such facilities. [YAMA2024]

Electrically controlled keys

Locks for doors and windows could be controlled electrically. For a security measure, a single push of "leaving the house" button locks the doors and windows. It is explained in [YOUT-1], Such a mechanism has been commercialized and sold.

[end of Appendix]

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