Event‐triggered shared control for Euler–Lagrange systems with actuator fault and unknown control direction

Abstract

Security is of paramount importance in the operation of human‐controlled mechanical systems. In the unfortunate event of an accident, the operator may find themselves in a state of distress. This research focuses on the study of adaptive event‐triggered shared control techniques for uncertain Euler–Lagrange systems afflicted by actuator faults and the presence of unknown disturbances. Unlike existing results on shared control, the uncertain Euler–Lagrange system considered in this study contains both an unknown control direction and actuator faults, making it more practical. Furthermore, the controller we have designed demonstrates enhanced stability in the face of these challenges. To counteract the impact of unknown control direction, we introduce a state feedback controller employing Nussbaum functions. Additionally, the devised event‐triggered mechanism serves to reduce the system's network communication resource utilization. The implementation of our shared control strategy ensures asymptotic tracking of target trajectories by the system's outputs while maintaining consistent operation within a defined safe region. Finally, a simulated example is presented to validate the effectiveness of our proposed methodologies.