Electromechanical Coupling Dynamic and Vibration Control of Robotic Grinding System for Thin-Walled Workpiece

Abstract

The robotic grinding system for a thin-walled workpiece is a multi-dimensional coupling system composed of a robot, a grinding spindle and the thin-walled workpiece. In the grinding process, a dynamic coupling effect is generated, while the thin-walled workpiece stimulates elastic vibration; the grinding spindle, as an electromechanical coupling actuator, is sensitive to the elastic vibration in the form of load fluctuations. It is necessary to investigate the electromechanical coupling dynamic characteristics under the vibration coupling of the thin-walled workpiece as well as the vibration control of the robotic grinding system. Firstly, considering the dynamic coupling effect between the grinding spindle and thin-walled workpiece, a dynamic model of the grinding spindle and thin-walled workpiece coupling system is established. Secondly, based on this established coupling dynamic model, the vibration characteristics of the thin-walled workpiece and the electromechanical coupling dynamic characteristics of the grinding spindle are investigated. Finally, a speed adaptive control system for the grinding spindle is designed based on a fuzzy PI controller, which can achieve a stable speed for the grinding spindle under vibration coupling and has a certain suppression effect on the elastic vibration of the thin-walled workpiece at the same time.