Research On The Key Technology Of Compiled-typed Cnc System Based On USB Communication Interface

CNC system is the key part of NC machine. Its performance has a great impacton machining quality and efficiency. The technology of CNC system, as a leadingand strategic technology, has been given more and more attentions by all countries.The traditional CNC system is a closed system with special used architectureand the function extension, match of platform and reusability of modules have beengreatly limited. Nowdays the development of CNC system has become more open,highly modular and more networked to improve the interchangeability, scalability,portability and extensibility of CNC system.Currently the Open-NC system has several problems, such as the poor real-time capability of operating system and low machining efficiency and limitation ofinterpolation algorithm caused by the traditional interpretive mode of NC codes. Inthis paper a new kind of compiled-typed CNC system based on USB interface isbrought up. This kind of system adopts ping pong model to store data to reduce thereal-time demand of operating system and uses compiling mode which is widelyused in advanced computer language to process NC code. And the feasibility ofcomplied-typed CNC system has been verified in theory and experiment.The architecture of compiled-typed NC system has been advanced based on theanalysis of working principle of traditional CNC system and the design scheme ofthe system is established. The key technologies, including the choice of data storeand communication model, have also been analysed. The modular design method isused to develop the hardware system of compiled-typed CNC system. The wholesystem is divided into basic and extend functional module. Each module is furtherdivided. And the entire hardware system is builded. The data transmission mode anddriver model of USB interface, multithread technology and boot code on ARM arediscussed in detail to develop the software system. Then the communicationsoftware in PC system, drivers of USB interface and fixed programs in lowercomputer system are developed. The principle of decoding module and interpolationmodule are studied and the compiler of NC program in Windows system isdeveloped. After analyzing the drive system and reference frame of CK0630NClathe, the testing system of this system has been established.The compiled-typed CNC system is used to do virtual and machiningexperiment. Then the processing effect is compared with that of original CNCsystem. At last the further research priorities are put forward.