Design Of Motion Control Module Of Experimental Platform Based On EtherCAT Bus Technology

Traditional fieldbus technology is developing in the direction of industrial Ethernet.In the motion module of the experimental platform,the real-time industrial Ethernet protocol has become an important technology in motion control.The EtherCAT bus protocol,as a leader in industrial Ethernet technology,is due to its "on-The special mechanism of "the-fly" makes its communication efficiency high.It has the characteristics of fast response and good synchronization performance,and has an open source framework,which is favored by many small and micro innovative enterprises.This article designs and implements a motion control module based on X86 architecture using EtherCAT bus protocol.First of all,in view of the application problem of the motion control module of the experimental platform,the EtherCAT bus protocol’s network segment addressing,frame structure,state machine,distributed clock and other functions are deeply studied,the software scheme of the motion control module is explained,and the hardware The equipment was selected,the Ig H EtherCAT Master open source protocol stack was analyzed,and the overall scheme design of the motion control module was completed.Then,in view of the communication problem between the motion control module and the servo drive,the ESI file of the servo drive was analyzed and researched,the process data object mapping index was written,the Co E mailbox communication protocol model was established,and the communication client between the host computer and the motion control module was developed.End and server.Developed a motion planning algorithm,studied cubic polynomial trajectory interpolation and S-curve motion planning,and implemented functions on the motion control module to reduce the impact and vibration of the experimental platform during the initial,stop and change of motion.Through simulation and The calculation verifies the correctness of the motion planning algorithm.Then,the real-time performance and synchronization of the motion control module are studied.For the real-time performance,Linux+Xenomai dual-core is used.The motion control work with high real-time requirements is executed by the Xenomai kernel.In terms of synchronization,offset compensation and drift compensation are used.Research is carried out and the distributed clock synchronization function is added to improve the synchronization of the motion control module.Finally,using the X86 architecture host + CDHD servo drive + Omron IO board + DJTUPTX3-C1-NET three-axis platform,an experimental platform was built to conduct functional testing,real-time testing,and synchronization testing for the control module.The motion module of the experimental platform in this paper has complete functions,high real-time performance,and good synchronization performance.Experiments show that the motion control module can meet the requirements of motion control.