设计一种以实时以太网EtherCAT为基础的机器人伺服通信总线控制系统,具有时延小、可扩展性强的优点。分析实时以太网通信总线的网络诱导时延,采用最小二乘支持向量机对网络时延进行在线预测;在此基础上,采用可变时延自校正PID控制器,在线辨识控制对象的参数,适应控制对象模型的变化。仿真结果表明了网络延时预测的性能和网络控制系统的控制性能,该系统能够实现闭环稳定控制。
A communication bus and servo control system based on EtherCAT for robots was designed with little delay and good scalability.The network-induced delay of real-time Ethernet used as robot's communication bus was analyzed.The networkinduced delay online was predicted using LSSVM.The self-tuning PID control method with variable delay was adopted in network control system.The parameters of controlled objects were identified online,which adapted to the change of model.The simulation verifies the excellent performance of network delay prediction and network control,and the stable closed loop control can be realized.