Trajectory control of flexible robot arms using approximate position of end effector as the controlled point

摘要

This paper presents a trajectory control scheme for flexible robot arms using an approximate position of the end effector as the controlled point. The scheme consists of five parts, namely, (i) selection of the approximate position to guarantee the stability of zero dynamics and the non-singularity of the inverse dynamics, (ii) computation of the corrected reference trajectory for the controlled point, (iii) transformation of the Cartesian coordinates of the controlled point and its reference trajectory to the equivalent joint angles assuming that the arm is rigid, (iv) derivation of the control input to make the equivalent joint angles to track their reference trajectories, (v) stabilization of the elastic vibration modes by the LQ method. Simulation results show that the accurate and stable tracking is achieved by the proposed scheme.