Robust Finite-Time Command-Filtered Backstepping Control for Flexible-Joint Robots With Only Position Measurements
针对仅能测量位置的柔性关节机器人，提出一种结合有限时间扰动观测器的指令滤波反步控制方法，能同时估计不可测状态和匹配/非匹配扰动，并通过仿真和实验验证了其优于现有方法。
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.