Formation Tracking for a Multi-Auv System Based on an Adaptive Sliding Mode Method in the Water Flow Environment

TL;DR

This paper presents an adaptive sliding mode control method for multi-AUV formation tracking in 3D underwater environments, effectively handling water flow disturbances and ensuring stability through a robust control strategy.

Contribution

It introduces an improved adaptive sliding mode control approach with continuous terms and model predictive control for multi-AUV formation in water flow environments, enhancing robustness.

Findings

The proposed control method effectively tracks formation under water flow disturbances.

Simulations confirm the stability and robustness of the control strategy.

The approach reduces chattering and improves control smoothness.

Abstract

In this paper, formation tracking for a multi-AUV system (MAS) using an improved adaptive sliding mode control method is studied in the Three Dimensional (3-D) underwater environment. Firstly, the kinematics model and the dynamic model of the AUVs are given as the Six Dimensions of Freedom (6-DOF) considered. Then, control law based on the mathematical model of the AUVs is proposed based on the improved sliding mode method. A second order sliding mode control method is adopted to eliminate the chatting phenomenon of the controller. Thirdly, considering the water flow in the underwater working environment of the AUVs, an adaptive module is added to the controller. With the adaptive approach, the finite disturbances caused by water flow could be handled with the controller. The proposed method achieves stability by substituting an adaptive continuous term for the switching term in the controller. At last, a robust sliding mode controller with continuous model predictive control strategy for the multi-AUV system is developed to achieve leader-follower formation tracking under the presence of bounded flow disturbances, and simulations are implemented to confirm the effectiveness of the proposed method.