Dual-drive system for micro-manipulation of direct-drive robotic systems

摘要

A dual-drive system compensates for the effects of drive system nonlinearities for micro-manipulation of direct-drive robotic systems. The dual-drive system uses two actuators to drive a single manipulator joint. The extra actuator compensates for undesirable effects of the nonlinearities in the drive system by providing a correctional biasing force such as torque to the primary actuator. In a preferred embodiment, both actuators are DC motors and the biasing torque is modulated by monitoring the current in the primary motor winding. This torque monitoring can also be achieved by direct measurement, such as using a strain sensing element. The dual-drive system is capable of eliminating the effects of electromagnetic hysteresis and other nonlinearities in the amplifier-motor portion of a direct-drive robot arm. This system can be used to improve not only positioning performance, but also the dynamic manipulation of a robot manipulator.