This paper investigates the tool-workpiece contact mechanism in the disc polishing process, where the soft polishing disc touches the rigid freeform workpiece with a small tilt angle. The developed contact force model can explain how the contact parameters, including the disc contact depth, the disc tilt angle, the radii of curvature of the disc and the workpiece, affect the normal contact force. Under some reasonable geometric and mechanical assumptions of the disc and the workpiece, an approximated contact force equation is derived in a simple power-law form similar to the Hertzian contact model. The contact force is found to be positively related to the disc contact depth and the disc radius, while negatively related to the disc tilt angle and the workpiece normal curvature that is orthogonal to the feed direction. Both finite element simulations and experiments verify the effectiveness of the proposed contact force model. Furthermore, the material removal process is analyzed and a model-based process parameter planning method is developed to achieve uniform material removal considering the variation of workpiece curvatures.

本文研究了圆盘抛光过程中的工具-工件接触机制，其中软抛光盘以较小的倾斜角接触刚性自由形状的工件。建立的接触力模型可以解释接触参数（包括磁盘接触深度，磁盘倾斜角，磁盘和工件的曲率半径）如何影响法向接触力。在圆盘和工件的某些合理几何和机械假设下，以类似于赫兹接触模型的简单幂律形式推导了近似的接触力方程。发现接触力与光盘接触深度和光盘半径成正比，而与光盘倾斜角和正交于进给方向的工件法向曲率成反比。有限元模拟和实验都验证了所提出的接触力模型的有效性。此外，分析了材料去除过程，并开发了基于模型的过程参数计划方法，以考虑工件曲率的变化实现均匀的材料去除。