Control, Performance and Applications of Antagonist Actuated Manipulator Joints

Antagonist actuated joints are defined as being driven by a pair of opposing actuators, as in the arrangement of muscles in human joints. A simple method of controlling the motion and varying the compliance of the joint is presented, along with examples of the performance of a prototype joint. The use of antagonist actuators to reduce the size, inertia and backlash of manipulator arm joints is discussed. An antagonist actuated joint is one that is driven by a pair of opposing uni-directional actuators rather than by a single bi-directional actuator. This arrangement is necessary in human limbs since muscles can apply force in contraction only.