There is a credit in Rising Sun thanking "The MIT Leg Lab" and "Marc
Raibert and his Running Team." This refers to a short scene where
the two detectives go out to a fancy-looking research lab (really a
water treatment plant; also used as the set for Starfleet Academy on
the TV series "Star Trek - The Next Generation). In the background
of some of the shots there are two legged robots: one hopping in a
circle in a tea-house; the other bouncing up a garden path.
These robots are actually academic research projects from the MIT
AI Lab's Legged Locomotion Lab. They really do hop about and maintain
their balance. Power comes from off-board hydraulic pumps (hence the
guy in the background (me!) pulling hoses for the robot), and body
attitude is sensed with gyroscopes. A human with a joystick tells
the robot what direction to go, and the control algorithms (which are
the real subject of Leg Lab research) maintain speed, direction, and
balance.
However, the robots aren't designed for special effects. They're
always being modified, and they tend to break down frequently. This
made shooting in the hot july sun of the San Fernando Valley a real
nightmare, with transputers crashing in the heat, stuck gyros, and
hydraulic leaks.
Three grad students and a professor worked steadily for about a
month before Hollywood, and then five days on the set and on location
to get the robots in about 15 seconds of film. The credits are:
Marc Raibert (our prof), and Charles Francois, Rob Playter and Lee
Campbell (me) who are students. We three students appear in the film
in white lab coats acting like Robot Scientists!!