Abstract

The main objective of this thesis is to design and evaluate reconfigurable flight control system against control surfaces faults in Unmanned Aerial Vehicle (UAV) and aircraft without modifying the baseline controller/control law by using control re-allocation technique. The faults are introduced in the form of partial loss and stuck at unknown positions of control surfaces on the UAV and aircraft. Four control reallocation algorithms with applications to UAV and fixed-wing aircraft were investigated, which include a pseudo-inverse, a fixed-point algorithm, a direct control allocation algorithm and a weighted least squares method. The thesis work is evaluated by a nonlinear UAV model ALTAV (Almost-Light-Than-Air-Vehicles), developed by Quanser Inc., and a nonlinear aircraft model ADMIRE (Aero-Data-Model-in-Research-Environment), developed by the Group of Aeronautical Research and Technology in Europe (GARTEUR). Different faults have been introduced in control surfaces with different commanded inputs. Gaussian noise was introduced in the ALTAV model. Different faults have been introduced in control surfaces with different command inputs. Comparisons were made under normal situation, fault conditions without control re-allocation, and with control reallocation. Simulation results show the satisfactory reconfigurable flight control system performance using control re-allocation methods for ALTAV UAV model and ADMIRE aircraft model.