基于ObjectARX的激光切割数控自动编程系统开发

数控自动编程是数控系统向集成化、智能化发展的重要环节，对提高数控程序编制效率、可靠性和降低数控编程人员工作难度具有重要作用。针对LCM-408激光加工机床，基于AutoCAD平台的二次开发工具ObjectARX及Visual C++建立了图形交互式激光切割自动编程系统。采用Polyline图形实体描述激光切割路径，实现了Polyline的顶点和凸度等图形信息的自动提取，通过图形实体的AcDbExtent对象获取并计算出激光切割区域最小包络矩形的宽度和高度。为避免某些材料在激光切割过程中发生“过烧”现象，实现了激光切割元件轨迹的元件起割切入和最后切出部分的自动生成。并采用交互式依次选取切割元件，以及对切割元件进行分组的方法确定多个切割元件的切割顺序，并将相应的图形信息、加工路径信息等转换为相应的数控代码。通过激光切割轨迹的静态模拟初步实现了数控代码程序的校验。

Automatic Programming System for Numerically Controlled Laser Cutting Machine Based on ObjectARX

Automatic programming increasingly plays an important role in intelligent numerically controlled (NC) coding and Computer-Aided Manufacturing (CAM), which greatly improves the efficiency and reliability of NC system, and relieves the work loads of programming. A graphic automatic programming system for NC laser processing machine LCM-408 is developed by using ObjectARX in AutoCAD and Visual C++. Laser cutting path is presented with the employment of Polyline, in which vertex and bulge are searched out in turn by iterating all graphic entities. The height and width of the tight bounding box of cutting region are obtained by comparing the minimum point and maximum point of the AcDbExtent of each cutting entity. The cut-in or cut-out curve is automatically added to the beginning and ending of each cutting entity for improving the quality of the cutting edge. The cutting sequence can be modified by user choosing one after another or grouping the cutting entities. G-code is generated from the laser cutting path and verified with static simulation.