Cnc System Software Based On Rtlinux Development

Based on the previous achievements on developing a RTLinux-based CNC system, the thesis focuses on the overview of the development trending of CNC technology, the completeness of the frame of the RTLinux-based CNC system and the development of some associated modules.Some key issues of the development of the CNC system are addressed and investigated deep in detail, as follows:(1) To complete the frame of RTLinux-based CNC system. Due to the inherent disadvantages of DOS and Windows, a new concept of CNC system based on a free and real time operating system, RTLinux is introduced and a platform is developed. Moreover, some modules such as interpolation and position control modules have been completed in the environment of this platform.(2) Theoretical research and implementation of the CNC system error compensation. In the thesis, the software-based method for tpol length compensation is addressed, and some programmable formulas for tool radius compensation are summarized and used in the CNC system. A new software-based method for flexible thread pitch error compensation is proposed, considering the traditional equi-thread pitch error compensation and the usage of the CNC machine tools. Meantime, an algorithm to the error compensation of the tooth clearance is implemented.(3) Theoretical research and implementation of the speed-up and speed-down control in CNC system. An innovative algorithm of speed-up and speed-down control is proposed and implemented in detail.(4) The development of soft-PLC. Generally speaking, hard-PLC is used for control of machine tools' switch control in CNC systems, with the result of a poor universality and expensive price. The concept of soft-PLC is proposed to overcome the limits. Moreover, a soft-PLC system is developed.(5) To extend wed-based CNC technology. Up to now, CNC systems don't have or only has a little function of network, such as transferring NC file. With the development of IT, developer of PC-based CNC systems can easily develop function of network using PC's hardware and software resources. Network function is very important to CNC systems. For example, remote control is so convenient to maintain CNC systems that manufacturers can economize cost. A network programming idea of CNC is proposed and a module implementing remote control and file transferring is developed.(6) The development of data exchanging. The new idea of integrating the measurement and machining of CNC machine tools is proposed. In order to exchange data between CNC system and CAD/CAM system, a module of data exchanging is developed.