自动抛光凸区域上自由曲面的扫描路径算法

为了减小抛光加工的表面粗糙度和提高效率,构建抛光工具路径并均匀覆盖于三维曲面上,曲面的定义域为任意二维凸区域。扩展扫描方式根据曲面一个方向上的一组切割曲线的标准长度分布,灵活调整相应位置穿越的扫描线数量,既包含一般的贯穿曲面的曲线,又包含起点或终点在曲面内的曲线,与传统扫描方式相比具有很大灵活性。为优化扫描方向和确定扫描线的端点,给出了曲面立体光固化(STL)模型的边界提取算法。通过一个曲面的扫描路径建构实例,详细阐述了任意二维凸区域上扩展扫描的算法流程,包括曲面分割、点列筛选和路径点的连接等步骤。路径长度和相邻扫描曲线的间距分布定量地表明扩展扫描方式可适应曲面形状变化并提高路径覆盖均匀度。

Scanning path generation algorithms for automatic polishing of free-form surfaces in convex domains

Polishing tool paths were constructed to evenly cover a 3-D free-form surface defined within a 2-D convex domain to reduce surface roughness and improve efficiency. Unlike conventional methods, the extended scanning path can vary the number of scanning curves through one position according to the normalized length profile of a group of partitioning curves in a specified direction characterized by curves normal to each boundary and by curves starting or terminating within the surface. Boundary recognition algorithms were developed for the stereo lithography model to optimize the scanning direction and to locate the scanning curve end points. The extended scanning method was illustrated using a surface curve construction case, including surface partitioning, point selection and path point connection. The path length and the spacing interval distribution of neighboring scanning curves quantitatively show that the extended scanning path can adapt to surface variations and improve the coverage evenness.