Pentagon spends $50M on bionic men:
Robotic fish puts soldiers step closer to leaping buildings in single bound 

The Ottawa Citizen - February 22, 2001 - by Adam Sherwin

A giant leap for mankind may have begun with one small flip of a robotic
fish. The fish is the first robot to be powered by real muscles and American
military chiefs believe the same technology could be harnessed to enable
soldiers to leap tall buildings. 

The Pentagon is trying to develop robotic "muscle-suits" to give more power
to a soldier's natural movements. Like Steve Austin, the bionic man played by
Lee Majors in the 1970s television series The Six Million Dollar Man, anyone
wearing such a suit would be "better, stronger, faster."  

In research funded by the military, scientists at the Massachusetts Institute
of Technology built a robot fish that swam using live muscle tissue taken
from a frog. The leader of the research, Dr. Hugh Herr, has a special
interest in the project. 

An attack of frostbite cost him both his legs below the knee, and he believes
that his work could lead to improvements in artificial limbs. 

The robotic fish worked by using a microprocessor that sent electric signals
to frog muscles on either side, making them contract, New Scientist magazine
reports. Tendons on the muscles were sewn to the nose and tail and the
robotic fish wiggled and swam in response to the signals. The muscles took
their energy from a glucose solution in which the fish swam. 

The next step is to create another prototype that contains its own nourishing
glucose. Bigger muscles would need an artificial circulatory system to pump
the glucose to them. 

The Pentagon is spending $50 million U.S. on developing the muscle suits in
which real muscles would activate the robotic components. A spokesman for the
Pentagon's Defence Advanced Research Projects Agency said: "The idea would be
some kind of exoskeleton that would allow a soldier to have increased
strength, increased endurance, increased speed."  

The soldier would wear it as an outer skin, rather than operate it, and its
functions would optimally become an extension of the soldier's natural
movements. The suits, fully equipped with computers and communications gear,
would run on a compact power generator that would provide 24 hours of
continuous use. 

Agency documents claim that the suits will "augment human strength" and allow
soldiers to "leap extraordinary heights and distances."  The Pentagon plans
appear to be influenced by the mobile combat suits used to fight alien bugs
in the 1997 film Starship Troopers. 

Civilians could also feel the benefits. Artificial limbs tend to be stiffer
than real ones and cannot adapt to different surfaces. Prototype limbs
currently contain noisy joint motors. Dr. Herr said: "If all our muscles were
motors, we wouldn't hear ourselves talking."  

His next step is to improve the prototype robot by giving it a small stomach
to contain the nourishing glucose. Bigger muscles would need an artificial
circulatory system to pump the glucose to them. 

As long ago as 1786, Luigi Galvani discovered that electricity made a
dissected frog's leg twitch. But until now, nobody has tried to apply the
concept to power a machine. Dr. Herr's original robot has now expired, since
its muscles would keep only for a few hours. 

Another American team is reported to have succeeded in growing artificial
muscle cultures that live for several months. Bob Dennis, from the University
of Michigan, and his colleague Paul Kosnick, have persuaded human muscle
fibres to grow in the laboratory by simulating them electrically. It is the
first time that human muscle has been grown artificially. 

The pair believe that the technique might make some animal tests redundant
because chemicals could be tested on muscle cultures. Although the muscles
survive three to five months, compared with only a few hours for natural
muscle removed from the body, they are only a tenth as strong as the real
thing. Yoseph Bar-Cohen, who heads NASA's advanced actuators laboratory in
Pasadena, California, admitted: "There are issues of robustness with these
artificial muscles. They oxidize easily."  

Bob Dennis, a colleague of Dr. Herr, was skeptical. He said: "Why would
anyone want to build artificial muscle? Real muscle can adapt to its
environment, it can heal itself and it can self-regulate."