End-to-end flow control using PI controller for force control system over TCP/IP network

This paper presents a novel flow control method using PI controller for motion control system over network. UDP/IP protocol is known to be effective for motion control systems over network such as bilateral control system. However, UDP does not have a mechanism of congestion avoidance. The congestion, which causes large communication delay, jitter and packet loss, significantly deteriorates performance and stability of motion control systems. To avoid this congestion, a novel congestion control method, which adjusts a packet-sending period in real time, is proposed. The validity of the proposed method is shown by simulation and experimental results.