|Improved Four-channel PBTDPA Control Strategy Using Force Feedback Bilateral Teleoperation System
Xin Gong, Lixiao Wang, Yuanyuan Mou, Haili Wang, Xiaoqian Wei, Wenfeng Zheng*, and Lirong Yin*
International Journal of Control, Automation, and Systems, vol. 20, no. 3, pp.1002-1017, 2022
Abstract : Bilateral teleoperation robots with force feedback enable humans to accomplish these tasks without exposing them to these hazardous environments. Its stability and transparency describe the performance of bilateral teleoperation systems with force feedback. Bilateral teleoperation with force feedback enables humans to combine tactics with optesthesia. However, the force feedback may lead to bilateral teleoperation instability if the communication channels’ time delay exists. The instability of bilateral teleoperation with force feedback, which is brought in by the time delay, has become one of the complicated problems researchers need to solve. Transparency is one of the leading design objectives of the teleoperation system. There are two evaluation criteria for transparency: the accuracy of the position followed by the master mechanical arm and the accuracy of the feedback received by the slave arm from the master arm. The main content of this paper is as follows: 1) This paper researches and summarizes the control structures and control algorithms of several well-developed force-feedback bilateral teleoperation systems and decides to improve the PBTDPA algorithm, which aligns with practical application requirements. 2) The fourchannel structure makes the transparency of force-feedback bilateral teleoperation systems perfect in theory. This paper uses the four-channel structure combined with the PBTDPA algorithm to improve the transparency of the approach. 3) Moreover, the delay predictor is used to improve the four-channel power-based time domain passivity approach (PBTDPA) control strategy. The delay differential predictor is added to the communication channel. The delay change rate differential predictor can estimate the communication channel’s delay change rate instead of the maximum delay change rate to improve transparency. The simulation experiment of the improved control strategy was carried out. The results show the excellent performance of our design.
Bilateral teleoperation, delay, force feedback, PBTDPA, stability, transparency.