Target Force Tracking and Automatic Contour Surface Processing in Grinding of Industrial Robots

Abstract

Some studies have shown that constant grinding force has an appreciable impact on the quality of material removal, such as consistency. However, there are still two short-comings in practical applications. Firstly, it often produces a large instantaneous contact force when the grinding tool contacts the workpiece. Moreover, the grinding force fluctuates greatly in high feed speed. A series of practical solutions are proposed in our paper to these issues. A force planning strategy based on a compliance model can overcome the defect of excessive instantaneous contact force. Based on some functional modules of active disturbance rejection control (ADRC) framework, effective signals can be extracted, and some coarse disturbance feedback force can be eliminated. In addition, an impedance model combined with a PID regulator can realize fast suppression of grinding disturbance force and maintain target force. Besides, an algorithm prototype for automatic contour surface processing and target force tracking is proposed to simplify the programming of grinding. Physical experiments have proved the correctness and effectiveness of the above strategies.