Control Allocation and Re-allocation for a Modified Quadrotor Helicopter against Actuator Faults

This paper investigates the modification of a conventional quadrotor helicopter Unmanned Aerial Vehicle (UAV) by adding two actuators to the helicopter for increased hardware redundancy and enhanced Fault-Tolerant Control (FTC) capability. On one hand, this redundancy improves the helicopter's safety margin and on the other hand, it extends the FTC methods that can be flying-tested on the quadrotor with more severe faults/damages. For illustration, control re-allocation is employed as a fault-tolerant control method in the presence of actuator faults. Some experimental results using the quadrotor testbed at the Networked Autonomous Vehicles (NAV) Lab of the Department of Mechanical and Industrial Engineering of Concordia University are given to illustrate the capabilities of the modified UAV system.