船舶动力定位非线性自适应反步控制器设计

针对扰动不确定非线性船舶动力定位问题,提出了一种带观测器的不确定扰动非线性船舶动力定位自适应输出反馈控制.设计了一个非线性观测器,从附有噪声的输出中估计出船舶位置以及运动速度.用滤波后的位置信号,针对扰动不确定非线性船舶设计带观测器的自适应反步控制器,该控制在Backstepping设计方法的基础上引入积分环节,对存在未知参数和动态不确定扰动的船舶能有效的改善系统性能.根据Lyapunov稳定性理论证明所设计的控制器是全局渐近稳定的,仿真结果验证了该方法的有效性.

Design of nonlinear adaptive backstepping controller of dynamically positioned ships

Aiming at the problems of the nonlinear dynamic positioning systems(DPS) with uncertain disturbance,a nonlinear adaptive backstepping controller is proposed using vectorial observer.First,a nonlinear observer was derived,the proposed observer includes an estimation of both the position and velocity of the ship from noisy position measurements.Then the filtered position signal is used,an adaptive backstepping controller with observer is designed for the nonlinear ship.To improve the performance of the ship which has unknown parameter and uncertain dynamic disturbance,integral action is included into backstepping controller.Global asymptotic stability is proven by applying Lyapunov stability theory.Simulation results show that the designed controller is available and valid in ship dynamic positioning.