Globally finite-time stable three-dimensional trajectory-tracking control of underactuated UUVs

In this paper, the subject of the spatial trajectory-tracking control for underactuated unmanned underwater vehicles (UUVs) is addressed in the presence of model parameter perturbation and unknown ocean currents. The spatial trajectory-tracking guidance is established based on the dynamic virtual vehicle method, which continuously computes the desired motion states of an UUV to be used by the motion control system. The globally finite-time control strategy is proposed based on the proportional-integral-derivative sliding mode control (PIDSMC), which globally stabilizes all trajectory-tracking errors in the finite time. By all simulation results showing, this trajectory-tracking control strategy can drive the underactuated UUV with +/- 20% model parameter perturbation to track the predefined desired trajectory accurately in the three-dimensional space. All simulation results fully indicate that the tracking controller offer highly flexibility and strongly robustness in connection with the model parameters uncertainties.