Unmanned Aerial Vehicles operational requirements and fault-tolerant robust control in level flight

Unmanned Aerial Vehicles (UAVs) are playing an important role both in military as well as civilian applications. However, their role in civilian applications is hampered by the lack of adequate guidelines and operational requirements. In this paper a set of flight, operational and performance requirements for the use of fixed wing UAVs in civilian applications are collated from several resources in the public domain. The application of these requirements to the flight control of an unmanned fixed-wing aircraft is also addressed in this paper. A robust controller is designed to maintain the stability and the desired performance of the system in the presence of modeling uncertainty and measurement noise. A neural network based Fault Detection and Identification (FDI) scheme is then developed to estimate the effectiveness of control inputs. Finally, a reconfigurable controller is designed to compensate for the degradation of the actuation on the occurrence of a fault. Monte Carlo simulation is used to validate the capability and performance of the designed controller.