Passive and active fault tolerant control of octorotor UAV using Second Order Sliding Mode control

In this paper, Second Order Sliding Mode technique is used to develop a Passive Fault Tolerant Controller (PFTC) for octorotor UAVs. Super twisting algorithm is applied to form the discontinuous part of the controller. Optimal controller gains are found using Ecological Systems Algorithm, a bio-inspired optimization algorithm made to search within the stability region of the controller. An Active Fault Tolerant Controller (AFTC) version of the controller is designed using Pseudo-Inverse and Dynamic control re-allocation methods. SIMULINK based simulation results show the effectiveness of the proposed controllers which exceed the performance of First Order Sliding Mode active fault tolerant controller.