Path following control of underactuated autonomous underwater vehicles

To address the problem of path following of underactuated autonomous underwater vehicles(AUV) with parameter uncertainties and external disturbances, an adaptive fuzzy backstepping sliding mode system is designed. Firstly, the fuzzy logic system was used to approximate the unknown system function and backstepping sliding mode controller was designed by combining sliding mode control technology with backstepping thought. Then the vertical speed was controlled and the heading angle was as input of path following error, designing calm function and the change rate of following parameter. Finally, using Lyapunov stable theory to prove the stability of the controller. Simulation experiments show that the control system has good adaptability and robustness in case of parameter uncertainties and external disturbances to avoid shaking of performance.