Passive Fault Tolerant Control Allocations for Nonlinear Systems

This article presents a new fault-tolerant control scheme to achieve maneuvering control of multirotor unmanned aerial vehicle (UAV) system experienced the actuator faults and failures conditions. The suggested control method consists of two independent control modules, one for virtual control and the other for control allocations. A fixed control allocation scheme is deployed as a low-level control module to distribute/redistribute virtual control signals among the available actuators in the nominal/faulty situations without acquiring actuator health information. In order to cope with uncertainty due to actuator faults and to attain fast and finite-time convergence of tracking error, a high-level control module is designed using a higher-order integral sliding mode control method. A rigorous closed-loop stability analysis is carried out to show the system’s stability. Finally, the numerical simulations are conducted on a nonlinear model of a multirotor UAV system, demonstrating the efficacy of the suggested approach.