Online reference shaping with end-point position feedback for large acceleration avoidance on manipulator control

摘要

A nonlinear reference shaping method for manipulators which are operated in living environments is proposed. It generates an intermediate reference position, and it is combined with a control based on the virtual spring-damper hypothesis proposed by Arimoto et al. The initial acceleration is moderated by an intermediate reference position inserted between the original target and the current position of the manipulator's endpoint and by a second-order-lag filter. The endpoint position is fed back to the proposed controller to prevent from excessive trailing force and large acceleration. As the result, human-like smooth reaching motions and pliant behaviors against external forces are achieved. The validity of the proposed method is shown through computer simulations on a planar 4-DOF manipulator.