It has long been a desire of human beings to
project themselves into remote environments,
i.e. to have a sensation of being present or
existing in a different place other than the
place they really exist at the same time.
Another dream has been to amplify human
muscle power and sensing capability by using
machines while preserving human dexterity
and a sensation of direct operation.
In the late 1960s a research and develop-
ment program was planned on a powered
exoskeleton that a man would wear like a
garment. A concept of Hardiman was pro-
posed by General Electric Co. The idea was
that a man wearing the Hardiman exoskeleton
would be able to command a set of mechani-
cal muscles that multiply his strength by a
factor of 25, yet in this union of man and
machine he would feel objects and forces
almost as if he were in direct contact.
However, the project was unsuccessful for
the following reasons:
(1) It is potentially quite dangerous to wear a
powered exoskeleton when we consider
potential malfunction of the machine.
(2) Space inside the machine is required to
store computers, controllers, actuators
and the energy source of the machine,
which eliminated the space for a human
operator. Thus, the design proved
impractical in its original form.
Developments in science and technology have
now provided the means for an alternative
approach to realizing these dreams. The
concept of projecting ourselves by using
robots, computers and a cybernetic human
interface is called telexistence (tel-existence).
This concept expands to include projection in
a computer-generated virtual environment.
Figure 1 illustrates how telexistence has
evolved and emerged.
The realization of the concept of telexis-
tence was a fundamental principle of the eight
year Japanese National Large Scale Project
“Advanced Robot Technology in Hazardous
Environment,” which started in 1983 together
with the concept of Third Generation
Robotics. Through this project a theoretical
consideration of telexistence has been done
and its systematic design procedure has been
established. Experimental hardware telexis-
tence systems have been made and the
feasibility of the concept has been demon-
Volume 26 · Number 3 · 1999 · pp. 188–193
© MCB University Press · ISSN 0143-991X
Susumu Tachiis a Professor in the Department of
Mathematical Engineering and Information Science, at the
University of Tokyo, Tokyo, Japan.
Robots, Service, Telexistence, Teleoperation, VR
Telexistence (tele-existence) is technology which enables a
human being to have a real time sensation of being at a
remote location, while giving the person the ability to
interact with the remote and/or virtual environments. He
or she can “telexist” (tele-exist) in a real environment
where the robot exists or in a virtual environment that a
computer has generated. It is also possible to telexist in a
mixed environment of real and virtual, which is called
augmented telexistence. The concept of telexistence, i.e.
virtual existence in a remote or computer-generated
environment, has developed into a national R&D scheme
called R-Cubed (Real-time Remote Robotics). Based on the
scheme the National R&D Project of “Humanoid and
Human Friendly Robotics”, Humanoid Robotics Project
(HRP) in short, was launched in April 1998. This is an effort
to integrate telerobotics, network technology and virtual
reality into networked telexistence.
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