An EtherCAT-based motor drive for high precision motion systems

Industrial Ethernet-based motor drives offer many advantages for motion applications. This paper presents the implementation and analysis of a motor drive with the EtherCAT, an open real-time Ethernet standard, for high-precision motion systems. Considering the characteristics of the multitasked software and the network interface, we analyze the delay in actuating the motor in response to a command from the control host. Based on a response time analysis and the times measured from the developed drive, we discuss performance characteristics of the drive in respect of the end-to-end delay and the maximum achievable throughput for non-real-time traffic when the drive is controlled in position, velocity, or torque mode.