System Identification and Sliding Mode Depth Control of the Micro AUV SEMBIO

This paper presents an approach of system identification of the autonomous underwater vehicle (AUV) SEMBIO leading to a sliding mode depth controller for precise underwater movements. A dynamic model has been derived, including static nonlinearities induced by the brushless motors of the thrusters. This leads to advantages in comparison to common PID controllers eliminating effects of non-rotating thrusters due to small computed control variables. Different experiments under realistic conditions and resulting behaviors proving this statement are presented.