船舶运动纵向受扰力和受扰力矩估计方法研究

研究船舶纵向运动受扰力和力矩的估计对于船舶纵向减摇控制是非常必要的.针对典型船舶,建立了船舶纵向运动模型,论述了3种受扰估计方法,中心差分法、有色Kalman滤波方法及扩展Kalman滤波方法.仿真结果表明,以上3种估计方法均可行.若选取相同精度的测量仪表,扩展Kalman滤波估计效果最好,其估计方差相对值在10%以内,有色Kalman滤波估计次之,中心差分法估计最差,但中心差分法计算简便,而扩展Kalman滤波估计方法较繁,且需知干扰力和干扰力矩能量Rw的先验知识.若提高测量仪表精度,则中心差分法估计方差相对值明显改善,可提高到10%以内.

Estimation of longitudinal disturbing force and tortuosity of ship movement

The estimation of ship longitudinal disturbing force and tortuosity is vital for disturbance modeling and prediction as well as pitch reducing control. Based on a typical ship, this paper establishes a model of longitudinal movement and then discusses three ways of disturbance estimation: central difference, corlored Kalman filter and extended Kalman filter. Emulation indicates that the three methods are all feasible. With the same precision of measuring equipment, the extended Kalman filter has the best simulation result. The relative error of the estimation variance is less than 10%. The corlored Kalman filter performs second best, and using the central difference is the worst of the three. Even so, calculating the central difference is very simple. On the other hand,using the extended Kalman filter is complex, and requires knowledge about the energy of the disturbing force and tortuosity, that is R_w. If we heighten the precision of measuring equipment, the central difference's relative error of the estimation variance improved great, which is less than 10%.