中文摘要：

为了建立一个复杂程度适宜、精度满足要求的非线性船舶运动数学模型，用非线性状态空间数学模型做船舶回转试验，采用最小二乘法辨识出船舶的非线性参数，最后用得到的响应型非线性船舶运动数学模型做Z形试验，并与实船试验结果比较．研究结果表明，仿真曲线与实船试验曲线符合度较好，与状态空间模型相比，该模型计算比较简单，所得微分方程可保留非线性影响因素，可以满足进行船舶闭环控制系统仿真研究时对模型精度的要求．

英文摘要：

In order to build a nonlinear mathematical model useful for ship motion control with reasonable complexity and accuracy, a turning test for ships was carried out using a nonlinear state space mathematical model. These nonlinear parameters were then identified with the least square method, and finally a Z test was performed using the acquired mathematical model of nonlinear responding ship motion. Theoretical results were then compared to an actual ship test. Results show that the simulation curves tally with the experimental curves of the actual ship. Compared with the state space model, the computation of a responding ship model is simpler, but the differential equation can preserve the nonlinear effect and the model can also satisfy the requirements of model precision when the simulation of a ship closed-loop control system is studied.