Fault-tolerant control for reentry hypersonic vehicle with blended aerodynamic surfaces and RCS

This paper proposes a compound fault-tolerant control (FTC) scheme for a reentry hypersonic vehicle equipped with aerodynamic surfaces and reaction control system (RCS) under aerodynamic surfaces faults. Firstly, the healthy and faulty models of the vehicle are given. Secondly, in order to guarantee asymptotic attitude tracking, the sliding mode control technology is applied to obtain the desired control torque. Then, the control allocation (CA) maps the desired control torque into actuator commands. Aerodynamic surfaces act as the primary actuator, and the optimal CA of aerodynamic surfaces is realized based on the quadratic programming (QP) method. Whether faults occur or not, RCS is activated only when the desired control torque cannot be achieved using aerodynamic surfaces alone, and the insufficient torque is compensated by RCS. A novel CA method based on a fuzzy logic controller and a decision-making mechanism is proposed to solve the CA of RCS thrusters. Finally, simulation results are given to demonstrate the efficiency of the developed control scheme.