Study On Formation Control Of Vessels

The formation control problem for vessels is a practical and strategic issue for the military and civilian. In this paper, the problem of the formation control of multiple vessels is systematically studied, based on deeply analysis of native and foreign research results on the formation control problem of multiple agents and summary of existing problems in these results. The contents are as follows:Constraint relations of the formation include tracking constraints and formation constraints. Tracking constraints as the driving function of trajectory, which make each vessels track their reference trajectory, and formation constrained as a formation constraint function to ensure achieving the desired formation using the Lagrange multiplier. In order to achieve the formation of vessels, we designed a distributed control strategy. The distributed control strategy is reasonable by analysis the stability. Combined with the kinematic and dynamic model of vessels, we designed a formation controller using the distributed control strategy achieving the designed formation structure of vessels through feedback of formation information. Control targets are achieved with the proposed controller by simulation results.Security issue is an important aspect of the formation control, which includes collision avoidance and obstacle avoidance. We can make the minimum safe distance between the vessels to ensure any two vessels against collision in the process of formation. Obstacle avoidance is another issue in the formation control, by designing safety trajectory, ensuring the vessels through obstacle safely. Beside, taking the nonlinear model of the nonholonomic constraint of underactuated vessels into account, we design output-feed controllers to estimate velocity vector. Based on the safety problem of the formation control, we design a formation controller using the backstepping technique and Lyapunov method, achieving the desired formation control. Effectiveness of the proposed results is verified by simulation results on collision and obstacle avoidance.The main conclusions of this paper are summarized, and the work for future research is put forward.