Abstract
Usual repetitive control, when applied to path control of robots, cannot afford dynamical path speed changes, which correspond to changes in the reference period. This paper proposes a modified repetitive control that achieves feedforward control by switching the waveforms previously stored in several controllers according to speed changes, in an interpolating manner if necessary. An algorithm to implement the proposed method for robots is developed, and a deburring robot is actually constructed to change its path speed according to the cutting load, which is detected by the variation of tool revolutionary speed. Experimental results with test models show that the method can significantly reduce errors even when speed changes, and is advantageous to achieve accurate robots.
