This is Slave Zero, a half human scale robotic figure with 21 servo actuators & 42 degrees of freedom. Designed and built by Carl Pisaturo in 1997-8, with sculpted body panels by Frank Garvey. She and a mate are blurring the boundaries between sculpture, dance and theater while extending the language of each.
The SLAVE 0 series of robots have 21 servos driving 41 joints with thin cables. An electronic control system allows several widely spaced robots to be controlled by an operator, a stored program, or environmental stimulii. Each of the 2 built machines has a roughly human range of motion in the arms, wrists, neck and jaw. And in each hand, there are 8 linked joints driven by 2 servos. The torso also twists 180 degrees. Great effort has gone into making motions smooth - with adjustable damping of individual joints, high resolution servo control electronics, and software motion filtering. The arm span is 36", half human scale.
The servos are all off-figure to lighten the limbs, simplify servo replacement / tensioning / phasing and also to banish clutter from the figure. This necessitates a very complex cable transmission system, the design and fabrication of which was the biggest challenge of the project. The difficulty, one soon finds, is making a durable system that maintains constant cable-run lengths as joints along the path flex. In broad geometric terms, the cabling strategy is to route through the center of joints, bringing the cables into parallel for bending (as at the elbow) and into a tight group for twisting (as at the torso). Two technologies evolved to achive this: constant length bender modules and re-vector blocks.