Proceedings of the 35th International Symposium on Robotics (ISR2004), Paris-Nord Villepinte, France, March 23-26, 2004

Robotics Research toward Next-Generation
Human-Robot Networked Systems
Susumu TACHI, Ph.D.
Professor, The University of Tokyo
Department of Information Physics & Computing
7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 Japan
http://www.star.t.u-tokyo.ac.jp/
Abstract. Research on human-robot systems started as teleoperation and cybernetic prostheses in the 1940's. Teleoperation developed intotelerobotics, networked robotics, and telexistence. Telexistence is fundamentally a concept named for the technology that enables a humanbeing to have a real-time sensation of being at a place other than where he or she actually exists, and to interact with the remote environment,
which may be real, virtual, or a combination of both. It also refers to an advanced type of teleoperation system that enables an operator at thecontrol to perform remote tasks dexterously with the feeling of existing in a surrogate robot. Although conventional telexistence systems
provide an operator the real-time sensation of being in a remote environment, persons in the remote environment have only the sensation that asurrogate robot is present, not the operator. Mutual telexistence aims to solve this problem so that the existence of the operator is apparent topersons in the remote environment by providing mutual sensations of presence. This enables humans to be seemingly everywhere at the sametime, i.e., to be virtually ubiquitous. This paper reviews the generation of robots and the prospects of future networked robotics.
Keywords: generations of robots, networked robotics, real-time remote robotics (R-Cubed), humanoid robotics project (HRP), telexistence,
mutual telexistence, telepresence, virtual reality, retro-reflective projection technology (RPT)

1. Introduction

insurance, real estate, warehousing, transportation,communications, nuclear power, space, and ocean development,
to social work, such as medical treatment, welfare andsanitation, and to disaster control, leisure, household, and othertertiary industry-related fields.
Another dream of human beings has been to amplify
human muscle power and sensing capability by using machines
while reserving human dexterity with a sensation of direct
operation. Also it has long been a desire of human beings toproject themselves into a remote environment, that is, to have asensation of being present or existing at the same time in adifferent place other than the place they really exist, i.e., tobecome virtually ubiquitous.
This dream is now on the way to accomplishment using
robots as surrogates of ourselves over networks throughtechnologies such as virtual reality, augmented reality, wearable
systems and ubiquitous computing.
As this realization progresses our relations with the robot
are becoming more and more important. These are called
human-robot systems, human-robot interfaces, or human-robot
communications, and are also referred to as teleoperation,telerobotics, networked robotics, r-cubed (real-time remote

One of humanity's most ancient dreams has been to have asubstitute that can undertake those jobs that are dangerous,difficult or tedious. In primeval times, the dream was realized
by utilizing animals, and unfortunately, by using fellowmen as
slaves. In some countries, such conditions continued until
nearly a hundred years ago.
With the advent of robotics and automation technology,
and also the progress of computers and electronics in recent
years, it has become possible to let automated machinery
replace human labor. Robots are expected to replace human
work as the only tolerable slave from a humanitarian point ofview. The “Human Use of Human Beings” of N. Wiener willbe truly realized only when humans make robots to replacethem for adverse tasks, supporting an important end in thedevelopment and safety of our modern society.
The application fields are not limited only to ordinary
manufacturing in secondary industry, but have been expanding
gradually to mining, civil engineering and construction in thesame secondary industry, as well as to agriculture, forestry andfisheries in primary industry.
They are expanding also to retailing, wholesaling, finance,

1

S.Tachiapplication area is limited. These robots can be most effectively
used in manufacturing processes in secondary industry,
especially in material handling, painting, spot welding, etc.
In other areas, such as arc welding and assembling, it isnecessary to vary actions and to better understand human
instructions by using not only knowledge from within, like for
the First Generation Robot, but also to acquire external
information with sensors. A device that could change its actions
according to the situation using a sensor is the so-called
Second-Generation sensor-based adaptive robot. It came toprevail gradually in the 1970’s.
The non-manufacturing areas of primary industry(agriculture, fisheries, and forestry), secondary industry(mining and construction), and tertiary industry (security andinspection) had so far been excluded from mechanization andautomatization, as the older type First and Second Generation
robots could not operate in environments that were dangerous
and unregulated or unstructured. However, harsh andhazardous environments such as nuclear power plants, deep
oceans, and areas affected with natural disasters, are where
robots are needed the most as substitutes to humans who risk
their lives working there. The Third Generation Robot was
proposed to answer these problems.
The key to the development of the Third Generation
Robot was to figure out a way to enable the robot to work in anenvironment that was not maintained or structured. The Firstand Second Generation Robots possess the data of themaintained environment. This means that humans have a graspof the entire scope of data concerning the environment. This iscalled the “structured environment.” The factory where firstand second generation robots work is an example of thestructured environment. All the information concerning thestructure of the factory, such as where passages are and how
things are arranged, is clear. One can also change theenvironment to accommodate the robot. For example, objects
can be rearranged to where the robot's sensor can recognize
them easily.
However, there are structured environments that cannot bealtered so easily. For example, it is not possible to change theenvironment in places such as the reactor of a nuclear power
plant, objects in the ocean, and areas affected by disasters.
Even with full knowledge about the environment, one cannot
alter the environment to accommodate robots. In many cases,
one cannot determine the vantage points and lighting.
Furthermore, one can encounter an “unstructured environment”
where humans do not possess accurate data. Nature is also fullof environments where humans are totally disoriented.

robotics) or telexistence when robots are remotely placed.
These are some of the most undeveloped areas despite being
among the most important in robot technology.
An example of the human-robot cooperation system,
which will play an increasingly important role in the highly
networked society of today and the future, as well as topics
such as virtual reality and augmented realty for realizing such asystem will be presented and intensively discussed.

2. Generations of Robots
Since the latter half of the 1960’s, robots have beenbrought from the world of fiction to the practical world, and thedevelopment of the robot is characterized by generations, as in
the case of the computer.
With the rapid progress of science and technology afterWorld War II, the robot, which had been only a dream, came torealize some human or animal functions, although it had adifferent shape. Versatran and Unimate were the first robots
made commercially available in 1960, and were introduced toJapan in 1967. They are called industrial robots and can be said
to be the First Generation of robots finding practical use.
This is considered to have resulted from a combination of
two large areas of development after World War II: hardware
configuration and control technology for a remote operational
type mechanical hand (or manipulator), which had been underresearch and development for use in the hot radioactive cell ofa nuclear reactor, and automation technology for automatedmachinery or NC machine tools.
The term “industrial robot” is said to have originatedunder the title “Programmed Article Transfer,” which G. C.
Devol applied for registration in 1954 and which was registeredin 1961 in the United States. It has come into wide usage since
the American Mental Market, a U.S. journal, used theexpression in 1960. After passing through infancy in the latter
half of the 1960’s, the industrial robot reached the age ofpractical use in the 1970’s.
Thus the robot entered an age of prevalence in anticipationof a rapid increase in demand. That is why 1980 is called "thefirst year of the prevalence of the industrial robot." From atechnical point of view, however, the first generation robot thatfound wide use is a kind of repetition machine, which plays
back repeatedly its position and posture instructed in an
embedding process before commencement of operation.
In essence, it is a composite system of technology basedon control techniques for various automated machines and NC
machine tools, and design and control techniques ofmanipulators with multiple degrees of freedom. Naturally, the2Proceedings of the 35th International Symposium on Robotics (ISR2004), Paris-Nord Villepinte, France, March 23-26, 2004

augmentation of the real environment.
The concept of telexistence was proposed and patented inJapan in 1980, and became the fundamental guiding principleof the eight-year Japanese National Large Scale Project called"Advanced Robot Technology in Hazardous Environments,"
which was initiated in 1983 together with the concept of Third
Generation Robotics. Through this project, we made theoreticalconsiderations, established systematic design procedures,developed experimental hardware telexistence systems, anddemonstrated the feasibility of the concept.
Through the efforts of twenty years of research anddevelopment in the U.S., Europe and Japan [1-10], it has nearly
become possible for humans to use a humanoid robot in aremote environment as if it was an other self, i.e., they are able
to have the sensation of being just inside the robot in the
remote environment.
Our first report [5,7] proposed the principle of thetelexistence sensory display, and explicitly defined its design
procedure. The feasibility of a visual display with a sensationof presence was demonstrated through psychophysicalmeasurements using experimental visual telexistence apparatus.
A method was also proposed to develop a mobile telexistencesystem that can be driven remotely with both an auditory andvisual sensation of presence. A prototype mobile televehicle
system was constructed and the feasibility of the method wasevaluated.
In 1989, a preliminary evaluation experiment oftelexistence was conducted with the first prototype telexistence
master slave system for remote manipulation. An experimental
telexistence system for real and/or virtual environments was
designed and developed, and the efficacy and superiority of thetelexistence master-slave system over conventional
master-slave systems was demonstrated experimentally [11].

In the development of the Third Generation Robot, one
focused on the structuralization of the environment based on
available information. Robots conduct their work automaticallyonce the environment was structured, and worked under the
direction of humans in an environment that was not structured.
This system, called the supervisory controlled autonomous
mobile robot system, was the major paradigm of the Third
Generation Robot.
Thus the Third Generation Robot was able to work inplaces where humans possessed basic data of the environment
but were unable to alter the environment. These robots areengaged in security maintenance in such uncontrollable
environments, and could deal with unpredictable events withthe help of humans.
In Japan, between 1983 and 1991, the Ministry ofInternational Trade and Industry (now Ministry of Economy,
Trade and Industry) promoted the research and development of
a National Large-Scale Project under this paradigm called“Advanced Robot Technology in Hazardous Environments”.
Telexistence played an important role in the paradigm of theThird Generation robots.

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Brain
Function

1st generation

2nd generation

3rd generation

4th generation

Intelligence

A Priori [inborn]
Play back

Adaptation
Accommodation

Inference
Problem Solving

A Posteriori [acquired]
Learning, Neural Network

Knowledge

Data

Knowledge BaseCommon Sense

Exist

Exist

Internal
Information

SensorFunction

External
Information

Application
FieldsTechnical
FeatureExist

Unilateral

3-D
3-D
1-D, 2-D
Natural Environment
Structured Environment Unstructured Environment
Bilateral Communication
Bilateral Communication
Interactive(teaching, NC tape)(robot language)

None or Point

Communication

Effector
Function

Data Base

Exist

Manipulation Position Control(Static)
Locomotion 1-D(guide cable)

Position Control(Dynamic)

2-D(plane, guided)(supervisory control, telexistence)

Cooperative Control

3-D(structured)

3-D (unstructured)

Secondary Industry

Secondary Industry(manufacturing)(manufacturing)(nonmanufacturing)

Material handling,
Painting, Spot welding

Arc welding,
Assembly

Internal Sensor＋
Servo Control
Technology

External Sensor＋
Microprocessor
System Technology

Secondary Industry(natural language, gesture, body language)

Force Control

Primary Industry
Tertiary Industry(inspection, maintenance)

Knowledge Engineering＋
Man-MachineInterface Technology

Secondary Industry(nonmanufacturing)

Primary Industry
Tertiary Industry(office, hospital, home, service)

Virtual Reality＋
Network Technology

Fig. 1 Generations of Robots.

3. Telexistence
Telexistence (tel-existence) is a technology that enables us
to control remote objects and communicate with others in aremote environment with a real-time sensation of presence byusing surrogate robots, remote / local computers and cybernetic
human interfaces. This concept has been expanded to include
the projection of ourselves into computer-generated virtualenvironments, and also the use of a virtual environment for the

Fig. 2 Telexistence Surrogate Anthropomorphic Robot (TELESAR) at
Work (1988).

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S.TachiAugmented telexistence can be effectively used innumerous situations. For instance, to control a slave robot in apoor visibility environment, an experimental augmented
telexistence system was developed that uses a virtualenvironment model constructed from design data of the realenvironment. To use augmented reality in the control of a slave
robot, a calibration system using image measurements was
proposed for matching the real environment and theenvironment model [12].
The slave robot has an impedance control mechanism forcontact tasks and to compensate for errors that remain evenafter calibration. An experimental operation in a poor visibility
environment was successfully conducted by using a humanoid
robot called TELESAR(TELExistence Surrogate
Anthropomorphic Robot), shown in Figure 2, and its virtual
dual. Figure 3 shows the virtual TELESAR used in theexperiment, and Figure 4 shows the master system for thecontrol of both real TELESAR and virtual TELESAR.
Experimental studies of tracking tasks demonstrated
quantitatively that a human being can telexist in a remote
and/or computer-generated environment by using the dedicatedtelexistence master slave system [11].

telexist anywhere through a network, the Japanese Ministry of
Economy, Trade and Industry (METI) together with the
University of Tokyo, proposed a long-range national researchand development scheme in 1995 dubbed R-Cubed (Real-time
Remote Robotics) [13].
Figure 5 shows an example of an artist's rendition of afuture use of R-Cubed System. In this example, a handicapped
person climbs a mountain with his friends using a networked
telexistence system.
In an R-Cubed system, each robot site includes its local
robot's server. The robot type varies from a mobile camera on
the low end, to a humanoid on the high end. A virtual robot canalso be a controlled system to be telexisted.

Fig. 5 Mountain Climbing using R-Cubed.

Each client has a teleoperation system called a cockpit,
ranging from an ordinary personal computer system on the low
end to a control cockpit with master manipulators and a Head
Mounted Display (HMD), or a CAVE Automatic Virtual
Environment (CAVE) on the high end. RCML/RCTP(R-Cubed Manipulation Language / R-Cubed Transfer
Protocol) is now under development to support the lower end
user's ability to control remote robots through a network [13].
To standardize the following control scheme, a language
dubbed RCML (http://www.rcml.org), which describes a
remote robot's features and its working environment, has been
proposed. A communication protocol RCTP has also been
designed and developed to exchange control commands, statusdata, and sensory information between the robot and the user.

Fig. 3 Virtual TELESAR at Work (1993).

5. Humanoid Robotics Project (HRP)
After a two-year feasibility study called the Human
Friendly Network Robot (FNR), which was conducted from
April 1996 till March 1998 based on the R-Cubed Scheme, a
National Applied Science & Technology Project called“Humanoid and Human Friendly Robotics (HRP)” waslaunched in 1998. It is a five-year project toward the realization

Fig. 4 Telexistence Master (1989).

4. R-Cubed
In order to realize a society where everyone can freely

4Proceedings of the 35th International Symposium on Robotics (ISR2004), Paris-Nord Villepinte, France, March 23-26, 2004

display. This made the operator feel as if he or she was inside
the robot, walking around the robot site (Fig. 7).
A CG model of the robot in the virtual environment wasrepresented and updated according to the current location andorientation received from sensors on the real robot. The model
was displayed on the bottom-right screen of the surround visualdisplay, and by augmenting real images captured by the camera
system, it supported the operator's navigation of the robot.
Since the series of real images presented on the visual display
are integrated with the movement of the motion base, theoperator feels the real-time sensation of stepping up and down.
This was the first experiment and success of controlling ahumanoid biped robot using telexistence [15].

of a so-called R-Cubed Society by providing humanoid robots,
control cockpits and remote control protocols.
A novel robot system capable of assisting and cooperatingwith people is necessary for any human-centered system to be
used for activities such as the maintenance of plants or power
stations, the operation of construction work, the supply of aid
in case of emergency or disaster, and the care of elderly people.
If we consider such systems from both a technical and a safety
point of view, however, it is clearly intractable to develop acompletely autonomous robot system for these objectives.
The robot system should therefore be realized with the
combination of autonomous control and teleoperated control.
By introducing telexistence techniques through an advanced
type of teleoperated robot system, a human operator can beprovided with information about the robot's remote site in theform of natural audio, visual, and force feedback, thus invoking
the feeling of existing inside the robot itself [14,15].

Fig. 7 HRP Humanoid Robot at Work (2000).

6. Mutual Telexistence using RPT
By using a telexistence system, persons can control therobot by simply moving their bodies naturally, without using
verbal commands. The robot conforms to the person’s motion,and through sensors on board the robot the human can see, hearand feel as if they sensed the remote environment directly.
Persons can virtually exist in the remote environment without
actually being there.
For observers in the remote environment, however, thesituation is quite different: they see only the robot moving andspeaking. Although they can hear the voice and witness the
behaviour of the human operator through the robot, it does not
actually look like him or her. This means that the telexistence is
not yet mutual. In order to realize mutual telexistence, we havebeen pursuing the use of projection technology withretro-reflective material as a surface, which we call
Retro-reflective Projection Technology (RPT) [16,17,18,19].
RPT is a new approach to augmented reality (AR)combining the versatility of projection technology with thetangibility of physical objects. By using RPT in conjunction
with an HMP, the mutual telexistence problem can be solved as

Fig. 6 Telexistence Cockpit for Humanoid Control (2000).

In order to address the problem of narrow fields of view
associated with HMD's, a surround visual display using
immersive projection technology (as adopted in the CAVE),
has recently been developed (Fig. 6). The surround visualdisplay panoramically presents real images captured by a stereo
multi-camera system for a wide field of view mounted on the
robot, which allows the operator to have the feeling of
on-board motion when he or she uses the robot to walk around.
Various teleoperation experiments using the developedtelexistence master system confirmed that kinesthetic
presentation by the master system through visual imagery
greatly improves both the operator's sensation of walking, anddexterity at manipulating objects.
If the operator issued a command to move the robot, therobot actually walked to the goal. As the robot walked around,real images captured by a wide field of view multi-camera
system were displayed on four screens of the surrounded visual

5

S.Tachishown in Figure 8: suppose a human user A uses his
telexistence robot A' at the remote site where another humanuser B is present. The user B in turn uses another telexistence
robot B', which exists in the site where the user A works. 3-Dimages of the remote scenery are captured by cameras on board
both robots A' and B', and are sent to the HMP’s of humanusers A and B respectively, both with a sensation of presence.
Both telexistence robots A' and B' are seen as if they were theirrespective human users by projecting the real image of theusers onto their respective robots. The first demonstration of
RPT together with an HMP was made at SIGGRAPH98,
followed by demonstrations at SIGGRAPH99 and
SIGGRAPH2000.

Fig. 10 Head-Mounted Projector.

Motion Control / Tactile Control
Visual & Auditory Information

HMP

3D image observed by
Telexistence Robot B’is projected and observedby Human User B witha sensation of presence.

3D image observed by
Telexistence Robot A’
is projected and observed by
Human User A with asensation of presence.

Human
User A

Telexistence
Robot A’

Telexistence Robot B’
Telexistence Robot B’ isobserved as if it is Human
User B by the projectionof real image of B on
the robot B’.

Telexistence Robot A’ is HMP
observed as if it is Human
User A by the projectionof real image of A on
the robot A’.

Human
User B

Fig. 11 (A) Miniature of the HONDA Humanoid Robot,(B) Painted with Retro-reflective Material,

Visual & Auditory Information
Motion Control / Tactile Control(C) and (D) Examples of Projecting a Human onto it.
(adopted from [16]).

Fig. 8 Concept of Robotic Mutual Telexistence (adopted from [16]).

Figure 9 shows the principle of Retro-reflective Projection
Technology (RPT) and Figure 10 shows a Head-Mounted
Projector (HMP) constructed according to RPT [17,18,19].
Figure 11 presents an example of how mutual telexistence
can be achieved through the use of RPT. Figure 11(A) shows aminiature of the HONDA Humanoid Robot, while Figure11(B) shows the robot painted with retro-reflective material.
Figures 11 (C) and (D) show how they appear to a human
wearing an HMP. The telexisted robot looks just like the humanoperator of the robot, and mutual telexistence can be naturally
performed [16]. However, this preliminary experiment was
conducted off-line, and real-time experiments are yet to be
conducted by constructing and using a mutual telexistence
hardware system.

Fig. 9 Principle of Retro-reflective Projection Technology (RPT).

7. Toward the Future
There are two major styles or ways of thinking in

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Proceedings of the 35th International Symposium on Robotics (ISR2004), Paris-Nord Villepinte, France, March 23-26, 2004

this type of robot. Isaac Asimov's three laws of robotics, forexample, are quite relevant in designing this type of robot. It is
crucial to find a solution to make sure that machines would
never harm humans by any means.
The safety intelligence requires high technology and its
innovation will not an easy task. The intelligence must be
perfect, as a partially successful safety intelligence would be
totally useless. The robots need to possess safety intelligencethat even exceeds human intelligence. As Alan M. Turing hasargued, this idea was still not relevant in the twentieth century,
when autonomous robots could not have true intelligence ashumans have. However, inventing the safety intelligence is themost important mission in the twenty-first century as robots areabout to enter the everyday lives of humans.
On the other hand, there is an alternate approach to thisproblem. One could argue that the "one's other-self-robots"
rather than the "independent robots" should be the priority indevelopment. The other-self-robots are analogous toautomobiles. The robots are machines and tools to be used byhumans; robots are extensions of humans both intellectuallyand physically.
This approach pre-empts the problem of robots having
their own rights, as they remain extensions of humans.
Humans therefore need not to be threatened by robots, as therobots remain subordinate to humans. One's other-self-robot
therefore is a promising path that humans can follow.
Take nursing for example. It is not desirable for a nursing
robot that takes care of you to be an independent being. We canprotect the patient's privacy the most when it is the patient who
is taking care of himself. Accordingly, it is more appropriate if
the nursing robot is the other-self-robot, an extension of oneself.
The other-self-robot can either help himself or other people.
The other-self-robot is more secure than the robot as anindependent being, as the rights and the responsibilities
associated with the robot are evident in the former type. The
right and the responsibility of the robot belong to the humans
who own the robot as their other self. Robots cannot claim theirown rights or responsibilities.
One can nurse himself not only by using his own otherself-robot but also by asking family members and professional
nurses to take care of him by using robots. These people, who
may live far away from the patient, can use telexistence
technology to personify the robot near the patient to help him.
One important consideration in using this technology is thatthrough the robot the patient needs to feel as though a person
he knows, rather than an impersonal robot, is taking care ofhim. It is essential that the robot have a "face": a clear marker

designing robots. An important point to note here is that theseways of thinking have nothing to do with the forms of robots,
such as the distinction between humanoid robots or those withspecial forms. Other distinctions include those that performgeneral or specific functions, and those in the shapes of animals
or those that are not. These distinctions are indeed important
especially when the robots are applied to practical use, andmust be considered in practical situations.
However, the distinction that is discussed here concerns
the philosophy toward robot design per se. The two different
ways of thinking concern the question of whether to make"robots as independent beings" or "robots as extensions ofhumans". Robots as independent beings will ultimately have awill of their own, although that is far off from the stage ofdevelopment today. Accordingly, commands toward the robots
are made through language, such as spoken words, written
manuals, or computer instructions.
On the other hand, robots as extensions of humans do nothave a will of their own. Robots are a part of the humans whocommand them, and humans are the only ones who possess
will. Commands are made automatically according to human
movements and internal states, and not through language.
Robots move according to the human will.
A prime example of robots as extensions of humans is a
prosthetic upper-limb or an artificial arm, which substitutes lostarms. Humans move artificial arms as though they moved theirown arms. What if one gained an artificial arm as a third arm,in addition to the existing two arms? The artificial arm would
move according to the human will and function as an extra arm
extending the human ability. The artificial arm, or, a robot as anextension of human, could physically be separate from thehuman body; it would still move according to the human will
without receiving lingual commands. The robot would not haveits own will and function as part of the human, even though therobot is physically separated from the human body. This iswhat can be called "one's other-self-robot". There may be
multiple other-self-robots.
It is also possible to create an environment where humans
feel as if they are inside one's other-self-robots, thereby thehuman cognizes the environment through the sense organs of
the robot and then operates the robot using its effect organs.
This technology is known as telexistence. Telexistence enables
humans to transcend time and space, and allow them to be
virtually ubiquitous.
Robots as independent beings must have the intelligencethat pre-empts any attempt of the robots to harm humans.
That is to say, "safety intelligence" is the number one priority in

7

S.Tachifinding out and replicating the working of human intelligence;the safety intelligence is a far more important and pressing
topic for research. Pursuit of research concerning these threeelements are essential to future technology as a whole, and willlead to the realization of twenty-first century robotics, i.e.,
Next-Generation Human-Robot Networked Systems.

of who personifies it.
The analogy with the automobile is effective inconsidering the importance of clarifying who is using the robot.
Just as the driver of a car, as opposed to the car itself, isresponsible for the consequences of the car, so is the personusing the robot is responsible for the robot's conduct. When
you interact with a robot controlled by someone else, you needto know who is using the robot. I call this concept a robot's"anti-anonymity". To put it simply, the concept refers to thevisibility of the face and figure of the robot's user.
In general, there are two major uses of one's
other-self-robots: one is to transcend time and space by
expanding one's existence, and the other is to supplement andextend human abilities by using the robot as part of oneself, as
exemplified by artificial arms and seeing-eye dog robots [20].
Furthermore, the ultimate use of the other-self-robot would be
to make an appreciator of oneself. It is a copy of oneself,
including its intelligence. The robot would memorize theintelligence and the behavioral patterns of its user by being
used through telexistence. The robot becomes, so to speak, thereplica of its user.
Computers can imitate language and memory; however,
only robots can imitate behaviors. One's other-self-robot spends
its daily life with its user as the other-self or a companion,
thereby recording that human individual’s behaviour. The robot
can exist after the user's death, serving as the remnant of thedeceased person, together with his photos, recorded voice,videotaped images, writings, paintings, and music
compositions that the person leaves behind. The otherself-robot therefore has a more extended use than the robot as
an independent being.
Thus "one's other-self," "anti-anonymity," and "safety
intelligence" will be the three pillars of technical elements thatare essential to future robots. As previously noted, the other selfmust be part of oneself even though it is physically separated,as the self and the other self share their lives. Accordingly, theother-selfness is the key to robots working in daily life space.
Research on this topic must take the concept of the humanbody into consideration.
Anti-anonymity means visibility of the user's face andfigures. The robot must indicate its user every time it is in use
through telexistence via a network. One needs not explain
how dangerous the world would be without a system thatenables this visibility of the user. In addition, the importance ofsafety intelligence is evident for one's other-self robots as well.
A paradigm shift is essential in this research in the sensethat the research of intelligence should not be focused on

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