Resilient Flight Control: An Architecture for Human Supervision of Automation

We address the problem of flight control in the presence of actuator anomalies. A supervisory control architecture that includes the actions of both a human pilot and an autopilot is proposed to ensure resilient tracking performance in the presence of anomalies. The pilot is tasked with supervisory, higher level decision-making tasks, such as anomaly detection, estimation, and command regulation. The autopilot is assigned a lower level task of accurate command following based on an adaptive control design. The main innovations in the proposed architecture are the use of human pilot in utilizing the concepts of capacity for maneuver (CfM) and graceful command degradation (GCD), both of which originate in cognitive sciences and a judicious combination of the pilot inputs and the autopilot control action. Together, they provide guidelines for a system to be resilient, which corresponds to the system's readiness to respond to unforeseen events. The supervisory control architecture is shown to be capable of achieving maximum CfM while allowing minimal GCD, as well as satisfactory command following postanomaly, resulting in resilient flight capabilities. The proposed controller is analyzed in a simulation study of a nonlinear F-16 aircraft model under actuator anomalies. It is shown through numerical studies that under suitable inputs from the pilot, the overall controller is able to deliver resilient flight.