Adaptive Prescribed Performance Control of A Flexible-Joint Robotic Manipulator With Dynamic Uncertainties

• Published in: IEEE transactions on cybernetics Vol. 52; no. 12; pp. 12905 - 12915
• Main Authors: Ma, Hui, Zhou, Qi, Li, Hongyi, Lu, Renquan
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 01.12.2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Adaptive control; Adaptive fuzzy control; Adaptive systems; Control methods; Control systems; Control systems design; Control theory; event-triggered control; Feedback control; flexible-joint robot; Fuzzy control; Fuzzy logic; Manipulator dynamics; Manipulators; Nonlinear dynamical systems; prescribed performance; Robot arms; Robot kinematics; Robots; Tracking errors; Transient performance; Uncertainty; unmodeled dynamics
• ISSN: 2168-2267; 2168-2275; 2168-2275
• DOI: 10.1109/TCYB.2021.3091531

An adaptive fuzzy control strategy is proposed for a single-link flexible-joint robotic manipulator (SFRM) with prescribed performance, in which the unknown nonlinearity is identified by adopting the fuzzy-logic system. By designing a performance function, the transient performance of the control system is guaranteed. To stabilize the SFRM, a dynamic signal is applied to handle the unmodeled dynamics. To cut down the communication load of the channel, the event-triggered control law is developed based on the switching threshold strategy. The Lyapunov stability theory and backstepping technique are applied coordinately to design the control strategy. The semiglobally ultimately uniformly boundedness can be ensured for all signals in the closed-loop system. The designed control method can also guarantee that the tracking error can converge to a small neighborhood of zero within the prescribed performance boundaries. At the end of the article, two illustrative examples are shown to validate the designed event-triggered controller.