Modelling and Backstepping Motion Control of the Aircraft Skin Inspection Robot

Aircraft skin health concerns whether the aircraft can fly safely. In this paper, an improved mechanical structure of the aircraft skin inspection robot was introduced. Considering that the aircraft skin surface is a curved environment, we assume that the curved environment is equivalent to an inclined plane with a change in inclination. Based on this assumption, the Cartesian dynamics model of the robot is established using the Lagrange method. In order to control the robot's movement position accurately, a position backstepping control scheme for the aircraft skin inspection robot was presented. According to the dynamic model and taking into account the problems faced by the robot during its movement, a position constrained controller of the aircraft skin inspection robot is designed using the barrier Lyapunov function. Aiming at the disturbances in the robot, we adopt a fuzzy system to approximate the unknown dynamics related with system states. Finally, the simulation results of the designed position constrained controller were compared with the sliding mode controller, and prove the validity of the position constrained controller.