Servo - September 2016

We all know that the nuclear power we use today for electricity, ships, and submarines is utilized in the same way as we use coal and gas to produce electricity: by boiling water to drive a steam turbine. I never saw Steve Austin spouting steam as he ran along at 60 MPH, nor water dripping out of his right elbow as he lifted a car. Even the one ton (on Earth) multi-billion dollar Mars Science Laboratory, Curiosity obtains only 125 watts of electricity from its radioisotope thermoelectric generator (RTG) shown in Figure 13, which is powered by 11 pounds of decaying hot plutonium-238 dioxide.

The main advantage of nuclear fission reactors or decaying radioactive isotopes to produce electric power is that they last for years on just a small amount of fuel for the needed heat. As a side note, the US has only 12 pounds of Pu238 remaining, so, let’s just forget this type of power for robots. Power capacity and density is still the Achilles’ heel of today’s robots.

There is Real Progress in Robot Hand Development

With all these negative thoughts put aside on robot hand capabilities, there is real progress being accomplished in robot hand development. I’m not referring to sci-fi atomic-powered robots, but actual robot prostheses for use on humans or by robots to simulate human hands. The hands shown in Figure 14

University of Washington illustrate the ultimate goal of completely replacing human hands with robotic equivalents. These are considered the most detailed and kinematically accurate biomimetic anthropomorphic robotic hands in that they function and appear the same as human hands.

The hand shown in Figure 15 is the i-Limb Ultra Rev 3 by Touch Bionics

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Figure 14. Robot hands by Zhe Xu of the

University of Washington, as seen on the IEEE Figure 15. i-Limb Ultra Rev 3 by Touch Bionics controlled by a mobile app or the wearer's muscle’s impulses. Figure 13. MSL Curiosity's RTG protruding out the back of the Mars rover.