【作者】 刘洋；

【导师】 徐志祥；

【作者基本信息】 大连理工大学 ， 机械电子工程， 2006， 硕士

【摘要】 本文研究了STEP-NC标准在开放式数控系统中的实现问题,并通过实验验证了研究结果的可行性。 整个数控系统由上位PC机和下位DSP(Digital Signal Processor)模板两部分组成。PC机主要负责将STEP-NC代码转换到G代码以及通过USB2.0接口向DSP传送数控指令;下位TMS F2812型DSP芯片则主要用于实现复杂的插补及控制算法,并以西门子伺服驱动放大器和交流伺服电机作为驱动单元,对改造后的数控铣床各轴进行位置控制。 论文重点研究了STEP-NC代码向G代码的转换方法,主要包括:STEP-NC标准的文件架构及内容分析;STEP-NC文件中重要加工信息的提取方法及原则:工件某些典型特征的识别方法;具体走刀路径的形成原理;以及最后向G代码的转换的方法。之后,研究了以USB2.0标准作为数控系统中数据传输接口的方法,通过编写PC端Windows驱动程序和DSP端的固件程序,实现了上下位机之间的数据传输。最后,在VC++编程环境中利用MFC类库开发了用于数据传送及机床当前坐标实时显示等功能的用户接口界面。 实验结果表明STEP-NC转换成G代码后可传送至改造后的数控机床上运行;USB驱动程序运行正常,用户接口界面美观实用,达到了课题的要求,并为下一步的研究工作奠定了良好的基础。更多还原

【Abstract】 This contribution has investigated applying STEP-NC standards to open CNC system, and then demonstrated the feasibility of the research turnouts.The open CNC system consists of an upper PC and a lower DSP (Digital Signal Processor). The PC takes charge of the converting STEP-NC into G code and transferring G code to DSP module through USB2.0 interface. The lower DSP (TMS F2812) is used to realize the interpolation and control of three axes for the retrofitted CNC milling machine equipped with SIEMENS servo drive amplifiers and AC servo motors.The main focus of the work is the method of converting STEP-NC code into G code, which includes the analysis of STEP-NC standard file’s structure and content, the rules of extraction of important machining information, the recognition of class features, the rules of tool path’s generation and the method of final converting to G code. The second part of the research is the method of data transferring based on USB2.0 in CNC system. USB links the upper PC and the lower DSP by programming the windows driver on PC and firmware on DSP. Finally the end-user interface is developed with MFC in VC++ environment, which can transfer data and display the axes locations on-line.The experimental results have demonstrated that the converted G code from STEP-NC can be fully transferred to the retrofitted CNC milling machine for execution. The developed USB driver works well and the human-machine interface is carefully arranged and thus is friendly. All work in the paper forms a sound base for the coming research activities thereafter.更多还原