Event-Triggered Adaptive Sliding Mode Fault-Tolerant Control for UAVs with Self-Adjusting Constraint Boundary

A performance-guaranteed robust control scheme is proposed to tackle the challenges of external disturbances, actuator faults, performance constraints, and limited communication resources in the attitude control of unmanned aerial vehicles. By introducing the initial value of the tracking error and its sign, an adaptive performance constraint boundary is designed, which enables quantitative control over the overshoot, convergence time, and steady-state error. This approach overcomes the limitation of existing methods that require the initial tracking error to be within the initial constraint boundary. Furthermore, a modified sliding variable is constructed to eliminate the reaching phase, upon which a barrier function adaptive sliding mode controller is developed to smoothly adjust the adaptive gain, thereby effectively compensating for uncertain disturbances and actuator faults. In addition, the performance function is employed as an event-triggering condition to optimize communication resource utilization. Theoretical analysis and numerical simulations validate the effectiveness and superiority of the proposed method.