Output Constraint Adaptive Finite‐Time Sliding Mode Controller Design for Uncertain Quadrotor With Actuator Fault

ABSTRACT Quadrotor dynamics are always difficult to obtain precisely due to imprecise parameters, unmodelled dynamics. External disturbance like wind gust is always there, and there may be a possibility of unexpected actuator fault as well. It requires a robust control scheme to deal with issues. This paper presents a robust control scheme using sliding mode control while considering uncertain quadrotor parameters and actuator fault scenarios. In addition, the output states are guaranteed to stay within the user‐defined limits set a apripori, which becomes suitable in application for navigation in constraint spaces. Moreover, the proposed approach does not require any fault detection and diagnosis unit, which may increase the onboard computation otherwise; instead, an adaptive control scheme is developed to counter actuator fault. To handle the uncertainties, these are assumed as a state‐dependent structure and adaptive laws have been obtained to counter the uncertainties. Finally, the overall system stability is guaranteed in finite time along with the boundedness of all the adaptive parameters, which is non‐trivial. The proposed approach has been validated for quadrotor trajectory tracking scenarios in the presence of external disturbances, parametric uncertainties and actuator faults and a comparative analysis is performed with the existing approach.