以曲面形状简单、可直接仿制的产品为对象,提出了由工业计算机断层成像技术图像直接生成数控代码的方法。该方法首先对产品的切片图像进行边缘提取与轮廓跟踪,再采用B样条曲线进行轮廓拟合,然后引入平面任意区域加工填充技术,逐层生成刀具路径并进行有序连接,最后生成数控代码。在B样条曲线拟合中,为了提高拟合精度,提出了一种基于特征点提取与线段类型识别的型值点选取法;在数控代码生成步骤中,改进了单层切片轮廓岛屿关系判别方法,提高了判别正确率。开发了软件系统,将该软件生成的数控代码输入到加工仿真软件中,仿真结果验证了数控代码生成方法的正确性。
Considering the product with simple surfaces only by direct copy, a method of generating Numerical Con- trol (NC) codes based on industrial Computed Tomography (CT) image was proposed. In this method, edge extrac- tion and contour tracking for slice image of product were conducted firstly, and B-spline curve was applied to contour fitting. Then, regional machining and filling technology in arbitrary plane was introduced to generate tool-paths slice by slice linking each other orderly. Finally, NC codes were generated automatically. In the B-spline curve fitting, an approach of selecting control points based on featured points extraction and line type's recognition was proposed to improve fitting accuracy. The method of judging relationship between the contour islands in monolayer slice was im- proved to increase the rate of discrimination accuracy in the procedure of transforming NC codes, Furthermore, a software system generating NC codes was developed. After NC codes generated by the software system were input to the milling-emulation software, the validity and feasibility of the method were verified.