A Passivity-Shortage Based Control Design for Teleoperation With Time-Varying Delays

• Published in: IEEE robotics and automation letters Vol. 5; no. 3; pp. 4070 - 4077
• Main Authors: Venkateswaran, Deepalakshmi Babu, Qu, Zhihua
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 01.07.2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Communication channels; Data transmission; Delay effects; Delays; ENGINEERING; Feedback control; Negative feedback; Passivity; passivity-based control; passivity-short systems; position control; Robot kinematics; Shortages; Stability; Stability analysis; Telerobotics and teleoperation; Time varying control
• ISSN: 2377-3766; 2377-3766
• DOI: 10.1109/LRA.2020.2988142

This letter investigates the effect of time-varying delays in bilateral teleoperation, with respect to stability and performance, using the properties of passivity-shortage. Until recently, the desired stability and performance characteristics were achieved using the concept of passivity. However, passivity is limited to systems of relative degree zero or one, while passivity-shortage includes systems of higher relative degrees and possibly of non-minimum phase. Passivity-shortage also arises naturally when data transmission is subject to delays, either constant or time-varying. In this letter, the properties of passivity-shortage are employed to design a simple negative feedback controller. We show that the proposed method provides a faster responding solution and improved performance compared to the existing approaches. The performance improvements include improved steady-state error convergence, and robustness against environmental disturbances, even in the presence of varying delays.