A Coordinated Dynamic Positioning Control Algorithm Based on Active Disturbance Rejection Control

The problem of coordinated dynamic positioning for multiple vessels in the presence of uncertainties and unknown exogenous disturbances is considered. A robust coordinated positioning control algorithm based on the active disturbance rejection control is proposed in this paper. The proposed coordinated controller is designed utilizing the position of each vessel and its relative distance with respect to adjacent vessels. In addition, the velocity of each vessel is introduced in the design so as to thruster forces drive the vessels to constitute asymptotically a desired formation. The proposed controller integrates the active disturbance rejection control (ADRC) method with the dynamic surface control method. The coordination controller is improved by arranging the transient dynamics for the motion of vessels and designing extended state observer for the dynamic positioning ship model. Simulation experiments have been carried out to evaluate the performance of the proposed approach in comparison with the conventional methods. Simulation results show the effectiveness of the proposed algorithm.