Robust Self-Scheduled Fault-Tolerant Control of a Quadrotor UAV

This paper deals with active fault-tolerant control (FTC) of a quadrotor in the presence of actuator faults. In previous studies, authors generally assume that the fault has been detected, isolated or identified and then proceed with a reconfigurable controller. This paper presents a complete active fault-tolerant control system with both fault detection and diagnosis (FDD) and FTC. The proposed FTC design is based on gain-scheduling control in the framework of structured H-infinity synthesis. The scheduled gains are parameterized as polynomial functions of the loss of control effectiveness of the quadrotor's actuators, estimated by a two-stage Kalman filter. Then, the MATLAB-based function systune tune the polynomial coefficients to meet the robustness and performance requirement. In comparison with other FTC systems which use switching mechanisms, this smooth self-scheduled controller allows one to avoid undesirable transient phenomenons during the controller reconfiguration process. Numerical simulations based on an underactuated 6DoF quadrotor nonlinear model show the good effectiveness of the proposed FTC in accommodating different levels of actuator faults. (C) 2017, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.