Control of underactuated AUVs: A flatness-based approach

The problem of tracking a desired trajectory for a nonlinear underactuated autonomous underwater vehicles (AUV´s) model with only three actuators is addressed. This paper proposes to compute offline open loop trajectories exploiting the liouvillian character of the nonlinear model. A flatness-based control approach is applied in the system linearized around the planned trajectories, which allows to obtain an incremental feedback controller to ensure a stabilization of the trajectory´s tracking error. In order to validate the proposed tracking control, simulation results are presented and discussed.