Design and implementation of a fault-tolerant controller using control allocation techniques in the presence of actuators saturation for a VTOL octorotor. Issue 9 (21st September 2022)

• Record Type: Journal Article
• Authors: Hafezi, Hamid; Bakhtiari, Ali; Khaki-Sedigh, Ali
• Is Part Of: Robotica. Volume 40:Issue 9(2022)
• Page Start: 3057
• Page End: 3076
• Publication Date: 2022-09-21
• Subjects: control allocation -- fault-tolerant control -- fault detection and diagnosis -- aerial robot -- octorotor; Robots -- Periodicals; 629.89205
• DOI: 10.1017/S0263574722000054
• Languages: English
• ISSNs: 0263-5747

Abstract

Abstract: Fault-tolerant control systems are vital in many industrial systems. Actuator redundancy is employed in advanced control strategies to increase system maneuverability, flexibility, safety, and fault tolerability. In this paper, a fault-tolerant control scheme is proposed to make an over-actuated octorotor robust, against actuators fault and saturation. A sliding mode observer is employed to determine the actuators condition. Then, a fault-tolerant control based on the control allocation methodology is proposed to distribute the control signals between the actuators by considering their condition. In a nonlinear system, an actuator fault can lead to the saturation of other actuators and steady-state errors that can cause closed-loop instability. Hence, the proposed control scheme corrects the actuator signals in a way that their limitations are considered. Finally, experimental studies are carried out and a comparison study is provided.