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Artificial Muscles Using EAP 287

devices. This is in contrast to commercial applications, for which issues of mass production,
consumer demand, and cost per unit can be critical to the transfer of technology to practical use.
Some of the challenges that are facing the users of EAP materials in expanding their potential
applications to space include their capability to respond at low or high temperatures.
Space applications are of great need for materials that can operate at single digit degrees of
Kelvin or at temperatures as high as hundreds of Celsius as on Venus. Another challenge to EAP
is the development of large scale EAP in the form of films, fibers, and others. The required
dimensions can be as large as several meters or kilometers and in such dimensions they can be
used to produce large gossamer structures such as antennas, solar sails, and various large optical
components.
In order to exploit the highest benefits from EAP, multidisciplinary international cooperative
efforts need to grow further among scientists, engineers, and other experts (e.g., medical doctors,
etc.). Experts in chemistry, materials science, electromechanics or robotics, computer science,
electronics, etc., need to advance the understanding of the material behavior, as well as develop
EAP materials with enhanced performance, processing techniques, and applications. Effective
feedback sensors and control algorithms are needed to address the unique and challenging aspects
of EAP actuators. If EAP-driven artificial muscles can be implanted into a human body, this
technology can make a tremendously positive impact on many human lives.
This field of EAP is far from mature and progress is expected to change the field in future
years. Recent technology advances led to the development of three EAP-actuated robotic arms
that wrestled with a 17-year-old female student who was the human opponent in the competition
held on March 7, 2005. Even though the 17-year-old student won against the three arms
the competition helped increase the visibility of the field worldwide and the recognition of
its potential. While more work is needed to reach the level of winning against humans it is
inevitable that this would happen just like the chess game between the champion and the
Big Blue IBM computer (http://www.geocities.com/siliconValley/lab/7378/comphis.htm). Ini-
tially, the challenge is to win a wrestling match against a human (any human) using a simple
shape arm with minimum functionality. However, the ultimate goal is to win against the strongest
human using as close as possible a resemblance of the shape and performance of the human arm.
Once such a robotic arm wins against humans, it would become clear that EAP performance has
reached a level where devices can be designed and produced with the many physical functions of
humans with far superior capability. Such a success is one of the ultimate goals of the field of
biomimetics.

ACKNOWLEDGMENT

Some of the research reported in this chapter was conducted at the Jet Propulsion Laboratory (JPL),
California Institute of Technology under a contract with National Aeronautics and Space Admin-
istration (NASA).

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