基于非线性模型预测的欠驱动船舶轨迹跟踪控制研究

Research on trajectory tracking control of underactuated ship based on nonlinear model prediction

针对欠驱动船舶轨迹跟踪控制系统具有非线性、大惯性、时滞、局部线性不可控等特点,结合扩展卡尔曼滤波器和序列二次规划算法,设计了基于非线性模型预测的船舶轨迹跟踪控制策略.首先,设计了具有一定复杂度的参考轨迹,用于测试船舶的各种工况及工况切换情况.其次,应用船舶欠驱动三自由度运动控制模型与所设计的参考轨迹建立了非线性约束优化问题的目标函数,采用序列二次规划算法进行优化求解,并在扩展卡尔曼滤波器中对测量函数的雅可比矩阵进行了预求解以减少算法计算量.最后,通过对一艘运输船进行仿真试验,验证了所设计轨迹跟踪控制器的有效性和实时性.

Aiming at the characteristics of underactuated ship trajectory tracking control system,such as nonlinearity,large inertia,time delay and uncontrollable local linearity,combined with extended Kalman filter and sequential quadratic programming algorithm,a ship trajectory tracking control strategy based on nonlinear model prediction is designed.Firstly,a reference trajectory with certain complexity is designed to test various working conditions and switching conditions of the ship.Secondly,the objective function of the nonlinear constrained optimization problem is established by using the ship underactuated 3-DOF motion control model and the designed reference trajectory.The sequential quadratic programming algorithm is used for optimization,and the Jacobian matrix of the measurement function is pre-solved in the extended Kalman filter to reduce the amount of calculation.Finally,through the simulation test of a transport ship,the effectiveness and real-time performance of the designed trajectory tracking controller are verified.