Fault Detection and Isolation for a 3-DOF Helicopter with Sliding Mode Strategies

This paper analyzes the problem of detection and isolation of faults in the actuators of a 3-Degree-of-Freedom (3-DOF) helicopter by a residual-based approach. A third-order sliding mode differentiator is designed for the evaluation of the residuals. Moreover, two sliding mode controllers are suitably designed to stabilize the angular positions and velocities: (i) a super twisting control system and (ii) a continuous twisting control system. The performance of the designed controllers and the effectiveness of the residual-based method are illustrated by simulations.