Adaptive Backstepping Control of Autonomous Undersea Vehicle with Input Limitation

For the axial position tracking control problem of an autonomous undersea vehicle (AUV) with input limitation, a controller is designed using the adaptive backstepping technology. The hyperbolic tangent smooth function is used to ensure bounded control input, a sliding mode control term is used to overcome the damping characteristic of the unmodeled part, and adaptation rate is designed to estimate the current speed. According to the Lyapunov theory, this controller can realize tracking control of the axial position and ensure that the tracking error of the system is globally uni-form and ultimately bounded. Simulation results show that the output of the controller is smooth and bounded, and it has good adaptability and certain robustness.