Finite-time observer based tracking control of uncertain heterogeneous underwater vehicles using adaptive sliding mode approach

In this study, a finite-time consensus tracking problem is investigated for a group of autonomous underwater vehicles (AUVs) with heterogeneous uncertain dynamics. We firstly propose a two-layer distributed control strategy, which consists of an upper-layer distributed observer and a lower-layer controller, without using any global information. Based on Hölder's inequality and the theory of finite-time stability, a distributed finite-time observer is developed for each follower to estimate the position information of a leader (i.e., an exosystem). Based on the sliding mode control method, a consensus tracking control scheme is designed for each AUV, by which all follower AUVs can track the leader in finite time. Secondly, when the parameters in the AUV dynamics are uncertain, a parameter-adaptive sliding mode control algorithm is introduced to improve the control performance. Finally, simulation results are presented to demonstrate the effectiveness of the proposed control algorithms.