【作者】 郭万庶；

【导师】 任俊生；

【作者基本信息】 大连海事大学 ， 交通信息工程及控制， 2010， 硕士

【摘要】 航海模拟器在驾驶员培训、航道设计等诸多领域发挥着越来越重要的作用。随着船舶向着大型化发展,拖轮协助大型船舶操纵已经成为了十分重要的手段。2007年挪威船级社对航海模拟器的认证标准提出了A级和B级船桥模拟器都应至少包括一个拖轮模拟器单元,故将拖轮协助大型船舶操纵的数学模型加入到航海模拟器中,实现拖轮拖带作业运动的仿真是非常必要的。本文将拖轮作为一个单独本船,通过缆绳拖带被拖船,把拖轮拖带作业的操纵数学模型加入到航海模拟器中来。为此,本文做了以下三个方面的工作：(1)建立了拖轮拖带作业的运动数学模型,使用龙格-库塔四阶(RK4)算法对模型进行解算。被拖船的数学模型是针对丹麦水池试验标准船模Mariner轮采用整体型建模理论建立的,拖轮的数学模型是采用分离建模理论建立的。同时还对所建立Mariner轮的数学模型进行了旋回试验和Z形试验,试验结果与实船试验结果基本吻合,表明所建模型满足精度要求。(2)建立了拖缆张力的计算模型。拖缆张力的计算分两种情况：一是拖缆应变小于25%时,满足虎克定律,利用悬链线方程推导出拖缆水平张力与无应力长度之间的一一对应关系,然后通过迭代法计算出拖缆的张力。二是拖缆应变大于25%时,不满足虎克定律,忽略拖缆自重,通过拖缆应变曲线图拟合的多项式来计算拖缆张力。本文以直径为96mm的尼龙单丝复合缆为例进行了实例验证,结果表明所建拖缆计算模型是正确和有效的。(3)搭建拖轮拖带作业的测试平台。本文基于Visual C++6.0语言环境开发了测试平台,对建立拖轮拖带作业的模型进行实时仿真测试。测试分为两个阶段：第一阶段拖轮与被拖船自航;第二阶段拖轮速度明显快于被拖船,当两船间距大于拖缆张力模型开始解算的水平距离时,拖缆张力模型开始解算,实现拖轮拖带被拖船运动的仿真测试,结果表明所建拖带作业模型是正确的。更多还原

【Abstract】 Marine simulator plays an increasingly significant role in merchant marine officer training and channel design and some other fields. Since modern vessel is becoming larger, tug assistance operation during maneuvering is rather important. So it is neces-sary to incorporate apply mathematic model of tug assistance during maneuvering into marine simulator. In the thesis, tugboat is an individual own-ship. It is connected through line with a towed ship to carryout towing operation. In this way, mathematic model of towing operation can be used in marine simulator. The main contribution of this thesis are as follows.Firstly, mathematic model of towing operation is established, which is solved with 4th-order Runge-Kutta algorithm. Mathematic model of towed vessel is in the frame work of Abkowitz Model, based on Mariner vessel. Tugboat mathematic model is built with MMG theory. Turning circle test and Zig-zag test are conducted. The test results meet Ship Maneuverability Standards of International Maritime Organization and model accuracy is satisfactory.Secondly, mathematic model of towing line tension is built. The mathematic model for calculating towing line tension contains two cases. In the first case that towing line elongation is less than 25%, which obeys Hooke’s Law, iterative algorithmis used to obtain line tension. In the second case, towing line elongation is more than 25%, which does not meet Hooke’s Law. Under this hypothesis, that line tension is calculated by using the regressive polynomial obtained through line stress-strain curve. The correct-ness and practicability of the model are verified by computation example.Thirdly, test platform is established for towing operation. The test contains two cases. In the first case, tugboat and towed vessel move independently. In the second case, towing operation simulation is in process. With Visual C++6.0 programming simulation for mathematic model is tested, which proves that the towing operation model is reasonable.更多还原