Fault Tolerant Control of a Blended Wing Body Aircraft using Priority Weighted Control Allocation and Sliding Modes

With far greater fuel economy and reduced noise, the Blended Wing Body is an efficient alternative to the conventional aircraft layout which, up to this point in time, has dominated commercial aviation. However, the combination of highly coupled effectors, limited control authority, poor intrinsic stability and significant mechanical redundancy results in a complex control problem. This paper proposes a sliding mode controller with priority weighted control allocation to handle the mechanical redundancy and coupling of the controls. Furthermore, in the presence of imprecisely known actuator faults and failures, the controller is designed to reconfigure and reduce degradation in the systems performance. Simulation results from a non-linear 6-DOF model demonstrate the controller's effectiveness in faulty flight conditions.