Position and Attitude Control Method Using Disturbance Observer for Station Keeping in Underwater Vehicle

This paper proposes the position and attitude control method using a disturbance observer for an underwater vehicle. When the underwater vehicle such as a remotely operated vehicle (ROV) and an autonomous underwater vehicle (AUV) moves, the position and attitude control of the underwater vehicle is important. In this situation, the underwater vehicle is affected by disturbances such as ocean current and tidal current. These disturbances have the bad influence to the position and attitude control of the underwater vehicle. In addition, the dynamic model of the underwater vehicle has the modeling error, since this shape is not simple. This modeling error also degrades the tracking performance. This paper proposes the robust position and attitude control system against disturbances and the modeling error for the station keeping in the underwater vehicle. In order to compensate for disturbances, the disturbance observer is implemented as the proposed method. The advantages of the disturbance observer is high robustness against these disturbances. It is possible to compensate not only disturbances but also modeling error by using the disturbance observer. The validity of the proposed method was confirmed from the simulation results.