Velocity Observer-Based Formation Control Approach for Multiple Under-Actuated Autonomous Underwater Vehicles Using Adaptive Back-Stepping Technique

In this work, an adaptive formation control scheme is designed for multiple under-actuated autonomous underwater vehicles (AUVs) subject to external disturbances. The leader-follower formation problem is divided into many decentralized subsystems. The follower AUV tries to keep a desired line-of-sight range and relative angle to its leader in each subsystem. The back-stepping procedure is then combined with an adaptive mechanism to compose a predefined formation of AUVs. Moreover, the leader’s velocity used in the control law is accurately estimated by a finite-time observer. Through Lyapunov stability analysis, it can be guaranteed that the formation control system is ultimately uniformly bounded. Finally, numerical simulation is used to demonstrate the feasibility and effectiveness of the proposed approach.