Research And Development Of Double-channel CNC System Based On EhtherCAT

With the increasing demand of the diversification of product function and the compound of processing technology in the numerical control industry,the market demand for the processing capacity of numerical control machine tools is also increasing.Multi-axis and multichannel control for compound processing has become one of the important characteristics of numerical control technology,and has a wide range of application requirements in the field of industrial production.Therefore,it is of great practical significance to design and develop a multi-axis and multi-channel CNC system.This paper selects EtherCAT,which is one of the mainstream Industrial Ethernet technologies,and LinuxCNC open CNC platform,which is widely used in the field of industrial control.Based on the in-depth research,this paper designs the dual channel CNC software of EtherCAT master station,and develops the software and hardware of the slave station motion control card.Finally,through a series of experiments and tests,the dual channel machining function of CNC system is successfully realized.The main work of the thesis could be summarized as follows:Firstly,the paper analyzes the composition of the double-channel CNC system,and proposes the master-slave system structure based on EtherCAT bus communication.Two CNC machine tools are controlled simultaneously by the host computer with two motion control board.Then,according to the overall structure of the system,the hardware and software design scheme of the system is determined.Secondly,according to the hardware design scheme,the main hardware structure of the system is analyzed in thesis.The main hardware structure of the system is analyzed and selected,and the related circuit is designed.Including the selection of PC hardware,the selection of the main chips of motion control board and the design of the corresponding connection circuit between these chips,as well as SOEM main configuration circuit design,such as optocoupler isolation circuit,differential signal output and input circuit,D/A converter circuit,I/O circuit,etc.Thirdly,according to the software design scheme,the software is developed on the basis of the system hardware,including the software design of the PC master station and the motioncontrol slave station.Among these,the software development of the master station includes the installation and real-time expansion of Linuxoperating system,the installation of LinuxCNC software and EtherCAT master software,the expansion and design of LinuxCNC internal structure,the driver design of EtherCAT master station,the configuration of Hal module,and the design of GUI.The main software development of slave station includes the design of ARM and FPGA program.Fourthly,the basic functions of the CNC system are verified by experiments.In practical application,the joint debugging of industrial control host,motion control card and servo device is completed,and the dual channel processing function is realized.