Adaptive event-triggered fault-tolerant tracking control for robotic arm systems based on fully actuated system approach

Abstract

An adaptive event-triggered fault-tolerant tracking controller is designed in this paper for a certain type of robotic arm systems with multiplicative actuator faults and uncertainties. First, the robotic arm model constructed by the Lagrange method is transformed into a second-order fully actuated system model. The high-order fully actuated (HOFA) system approach is employed in designing an intermediate controller, addressing the challenges posed by multiplicative actuator faults, while adaptive techniques are utilized to estimate unknown parameters. Second, for conserving system resources, the controller as well as its event-triggering system are designed. By the Lyapunov stability theory, the designed controller guarantees the stability of the system. Finally, through the simulation of a two-link robotic arm, the validity of the theoretical results gets verified.