The Design Of CNC System Based On Embedded Linux

CNC technology is a multi-disciplinary integration of micro-electronic technology,automation technology, detection technology, computer technology and so on, determines thelevel of national machinery, it has an important role in the development of the nationaleconomy.With the research on the status and development trend of CNC technology at home andabroad as well as open CNC system, and with the analysis on the structure and function ofCNC system, on account of the shortages such as structure is complicated and costly,hardware is redundant and can not be cutting, software versatility is poor, power consumptionis high and reliability is low, a set of universal CNC system solution is put forward, which isbased on hardware of embedded microprocessor ARM and DSP, software of embedded Linuxoperation system and graphical user interface tool MiniGUI.The system uses a dual-CPU architecture, the main controller of the host computer usesARM9as the system core modules, mainly to complete the man-machine interface functions,including the input function, display, storage, NC translation and interpretation function,communications, parameter settings function, on-site programming capabilities, themonitoring function, and fault diagnosis function, which do not ask for much real-time work,but highly require for the hardware storage and task scheduling. The motion controller of theslave computer is composed by DSP and FPGA, complete the interpolation operator andmotion planning, which has a response to interrupts, demand stringent real-time work. Hostand slave computer communicate through RS-485serial bus.After giving the overall architecture design of system, and software and hardwareplatform selection, focusing on the main controller of the host computer. Host controllerhardware circuit was designed in a modular fashion, including the ARM core board andbackplane circuit, and elaborated on ARM and FPGA hardware connection; buildingembedded Linux system platform and cross-compiler and debugging developmentenvironment based on the “host-target” structure. Given the multi-tasking, modular software architecture of host computer, Linux MiniGUI-Threads, multi-threaded mode is used todesign human-computer interaction module, communication module and servo-drivenmonitoring and debugging module, including man-machine interface design, ARM and DSPcommunication protocol design, the servo drive controller debugging tool design and so on.Finally the hardware, modular software and the system as a whole are debugged in thelaboratory stage, and get the desired results. The results show that the feasibility of thetechnical means of embedded Linux-based CNC system, and lays the foundation for the nextstep of riching system function, optimizing and improving.