PELOS-based path following control for autonomous underwater vehicle with input saturation and dead-zone

This paper focuses on horizontal path following control with prescribed performance for an autonomous underwater vehicle (AUV) with input saturation nonlinearity and dead -zone nonlinearity. The proposed control scheme consists of two functional parts, namely prescribed -performance line -of -sight with extended state observer (PELOS) based guidance and nonlinear model predictive control (MPC) based attitude control. Firstly, PELOS guidance is derived with an error transformed function such that the path following errors are restricted in the prescribed maximum overshoot and converge at a rate not lower than the prescribed convergence rate bound. Subsequently, the dedicated MPC with a smooth inverse dead -zone model is designed to remove the chattering phenomenon caused by dead -zone nonlinearity. It is illustrated that with the help of the designed controller, required transient and steady constraints of path following errors are never violated and the control input is chattering -free and smooth despite of the influence of saturation and dead -zone of actuators. Finally, three comparative numerical simulation results are carried out to demonstrate the effectiveness and advantages of the proposed path following control method.