have developed a robot that exhibits catlike motion in free fall. This work could ultimately lead to eliminating retrorockets, gas jets and gyroscopes in satellites and other spacecraft.
The robot, thus far tested only under less-than-ideal conditions in a university lab, rotates without angular momentum by changing the length of parts of its body while rotating them in opposite directions, much as a falling cat does. A successful NASA test of the concept could transform all space gear now based on gyroscopes — including satellites, the space station and the space shuttle — by enabling precise, vernier-like orientation control with zero angular momentum.
The robot is scheduled to fly this week in a NASA KC-135a to test the theory. See also EE Times Article.