MECHANISM DESIGN AND MOTION PLANNING OF PARALLEL-CHAIN NONHOLONOMIC MANIPULATOR

摘要

Inspired by the nonholonomic theory, this paper proposes a parallel-chain nonholonomic manipulator with a chainable kinetics model. To build the manipulator, the friction disc motion synthesis and decomposition mechanism was taken as the joint transmission component. Based on Chow's theorem, the kinetics model of the manipulator was proved as nonholonomic and controllable. Then, the system's configuration coordinates were mapped from the joint space to the chain space via coordinate transformation, and the manipulator motion was planned in the chain space. Through two simulation experiments, it is proved that all joints of the proposed manipulator can move to the target configuration within the specified time. To sum up, the author successfully built an underactuated manipulator that can drive the motion of four joints with two motors. The research findings lay the basis for the development of small lightweight manipulators.