Automatic Generation of Interference-Free and Posture-Smooth Toolpath for Robotic Belt Grinding of Complex Workpieces

Robotic belt grinding has shown great potential to achieve automatic machining of high-precision parts. However, its productivity in machining complex parts has been greatly limited by the problem that interference-free and posture-smooth toolpath planning is still a time-consuming and labor-intensive job. Therefore, this work presents a fully automatic and practical approach to facilitate interference-free and posture-smooth toolpath planning for robotic belt grinding of complex parts. With this approach, the interference correction spaces in two common belt grinding modes, namely, wheel face grinding and wheel edge grinding, are first established, where various types of interferences and their corresponding correction strategies are modeled. Then, two B-spline posture curves, which represent the rotational motion and translational motion of the workpiece for correcting interference throughout the entire cutter contact curve, are presented. With the two B-spline curves, a toolpath planning algorithm for robotic belt grinding of complex parts is further developed based on surface partitioning and iteratively correcting interference and smoothing grinding postures. The effectiveness and practicability of the proposed approach are validated by simulations and experimental studies, which demonstrates that the authors' approach can significantly improve the toolpath planning efficiency and ground surface quality for complex parts as compared with the leading commercial computer-aided manufacturing (CAM) software.