Design And Implementation Of A Synchronous Positon Detection Equipment Based On EtherCAT

EtherCAT fieldbus has been widely used in the industrial control system due to its excellent real-time synchronization performance.However,a large number of position detection devices in the current industrial control system have no access to the EtherCAT fieldbus when they have to be applied,such as detecting the position of multiple axes at the same time in the system of the multi-axis coordinated motion control and the complex surfaces contour detection.Therefore,a synchronous Positon Detection Equipment Based on EtherCAT is designed.The main research contents are as follows:After analyzing the demand of the practical engineering project,two main functional modules of the synchronous position detection equipment are proposed — the EtherCAT slave station communication function module and the synchronous position detection function module,and then the overall design scheme are put forward combining the functional requirements and the hierarchical design ideas.In view of the communication interface of the EtherCAT slave station,the hardware programming design of IP core based on FPGA is adopted to realize the function of the EtherCAT slave controller(ESC),and the corresponding hardware interface circuit is designed as well as the EtherCAT slave station communication protocol state machine based on STM32,what's more,the design is verified by simulation.Through the analysis on the position detection interface involved in the synchronous position detection equipment — the position signal input interface of the grating ruler and the trigger signal output interface of the laser displacement sensor,the corresponding interface design scheme is proposed.And then it is realized through the design of the hardware interface circuit and the FPGA firmware program.Besides,a synchronous position detection strategy is proposed and implemented.An experimental platform is set up to test the function of the EtherCAT communication and the position detection interface in the synchronous position detection equipment.The results show that the position detection device can be connected to the EtherCAT fieldbus control system with the synchronous Positon Detection Equipment Based on EtherCAT.