AUTHOR=Liang Xu , Su Tingting , Zhang Zhonghai , Zhang Jie , Liu Shengda , Zhao Quanliang , Yuan Junjie , Huang Can , Zhao Lei , He Guangping 

TITLE=An Adaptive Time-Varying Impedance Controller for Manipulators

JOURNAL=Frontiers in Neurorobotics

VOLUME=16

YEAR=2022

URL=https://www.frontiersin.org/journals/neurorobotics/articles/10.3389/fnbot.2022.789842

DOI=10.3389/fnbot.2022.789842

ISSN=1662-5218

ABSTRACT=<p>Aiming at the situation that the structural parameters of the general manipulators are uncertain, a time-varying impedance controller based on model reference adaptive control (MRAC) is proposed in this article. The proposed controller does not need to use acceleration-based feedback or to measure external loads and can tolerate considerable structure parameter errors. The global uniform asymptotic stability of the time-varying closed-loop system is analyzed, and a selection approach for control parameters is presented. It is demonstrated that, by using the proposed control parameter selection approach, the closed-loop system under the adaptive controller is equivalent to an existing result. The feasibility of the presented controller for the general manipulators is demonstrated by some numerical simulations.</p>