基于扩张状态观测器的有限时间船舶编队控制

Finite-time ship formation control based on extended state observer

[目的]为了解决大多数船舶编队控制算法控制周期长和时效性差的问题,提出一种基于扩张状态观测器(ESO)的有限时间控制策略。[方法]采用一种非线性终端滑模算法,通过对控制律分区域设计,克服传统终端滑模存在的奇异性问题;将非线性终端滑模与图论结合,实现有限时间的船舶编队控制;利用扩张状态观测器观测并补偿船舶模型中的不确定性及外界的干扰,以保证船舶编队控制的精确性;运用Lyapunov理论验证船舶编队控制律的稳定性。[结果]仿真结果表明,采用所提控制策略使整个编队系统误差在5 s左右趋近于0,从而实现了稳定。[结论]该控制策略能有效控制船舶编队,且控制速度快、时效性好。

[Objective]In order to solve the problems of most current ship formation control algorithms such as their long control cycle and poor timeliness, this paper proposes a finite-time control strategy based on an extended state observer(ESO).[Methods]First, a nonlinear terminal sliding-mode control algorithm is proposed which overcomes the singularity problem of the traditional terminal sliding-mode by designing the control law in different regions. Then, the nonlinear terminal sliding-mode control and graph theory are then combined to realize finite-time ship formation control. In addition, the ESO is used to observe and compensate for the uncertainties and external disturbances in the ship model in order to ensure the accuracy of ship formation control. Finally, the Lyapunov theorem are used to verify the stability of the ship formation control law.[Results]The simulation results show that the system error of the whole formation approaches zero in about five seconds using the proposed control strategy, thus its achieves stability.[Conclusions]The proposed control strategy can effectively control ship formation and has fast control speed and good timeliness.