Robust Finite-Time Command-Filtered Backstepping Control for Flexible-Joint Robots With Only Position Measurements

• Published in: IEEE transactions on systems, man, and cybernetics. Systems Vol. 54; no. 2; pp. 1 - 13
• Main Authors: Zhang, Yang, Zhang, Menghua, Du, Fuxin
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.02.2024; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Backstepping; Backstepping control; Closed loop systems; Closed loops; Controllers; disturbance observer; Disturbance observers; Feedback control; finite-time control; flexible-joint robot (FJR); Liapunov functions; Manipulators; matched/mismatched disturbance; Position measurement; Robot control; Robots; Robust control; Stability analysis; Trajectory tracking
• ISSN: 2168-2216; 2168-2232
• DOI: 10.1109/TSMC.2023.3324761

This article presents a robust finite-time command-filtered backstepping control strategy for flexible-joint robotic systems with only position measurements. To the best of our knowledge, this method is proposed for the first time and applied to the flexible-joint robot (FJR) system subject to matched/mismatched disturbances. Herein, two finite-time disturbance observers (FTDOs) are adopted to reconstruct unmeasurable system states and total matched and mismatched disturbances. By combining a finite-time command-filtered backstepping controller with two FTDOs, a novel robust command-filtered backstepping controller is presented. Meanwhile, the practically finite-time stability analysis of the closed-loop system is rigorously presented by the Lyapunov function. Finally, numerical simulations and experimental studies are carried out for the FJR, whose results show the superiority of the proposed scheme in comparison with the existing approaches, such as the FTCFBC, the ADRC, and the CSMC.