Limit-protection Method for Workspace of a Parallel Power Head

Abstract

The position and pose of the end of 1T2R mechanism with one translational motion and two rotational degrees of freedom in the operation space is the nonlinear mapping of the servo motor action in the joint space, and the postures and states of the end of the mechanism can only be obtained through complex modeling calculation. Because of this, the key problem to be solved urgently is to realize the real-time and accurate limit protection function of this kind of structure machine tool, and to reduce the process and calculation amount of the position and pose judgment of the end of the mechanism. In this paper, a simplified algorithm for position and attitude judgment is proposed by analyzing the workspace of 1T2R mechanism. The position and attitude judgment of the terminal moving platform of the mechanism under any configuration can be realized only by summing up the length of three branch chains of the mechanism and calculating the difference. Further, the limit protection method of parallel power head based on this algorithm can be implemented based on the software and hardware conditions of the existing control system. It is easy to implement and has a small amount of calculation, which can further improve the safety of the operation of such structure machine tools.