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1.
综述舰船运动极短期预报国内外的研究现状及采用的新方法,对各种方法进行了分析、评述,指出当前研究的重点和难点,并探讨了可供海上舰船实用的预防模式。  相似文献   

2.
突破舰船耐波性预报领域里极短期预报用时域分析法、短期预报用频域分析法的框架,从舰船实际运行需求出发,以风浪中预报舰载直升机安全起降时机为例,提出了先用频域分析法优选舰船在风浪中航向航速,再用时域预报方法,准确求出该航向航速上适于直升机起降的时刻,从而使舰—机组合能在较高海情下作业,井为舰船耐波性研究拓宽了领域。  相似文献   

3.
船舶运动极短期预报方法综述   总被引:1,自引:0,他引:1  
文章对船舶运动极短期预报技术进行了探讨和评价。论述了极短期运动预报的定义,从不同角度对极短期预报方法进行了分类。并对极短期预报方法的发展进行了叙述及讨论,分析了这些预报方法的优点和缺点,并对今后极短期运动预报技术研究的发展提出了建议。  相似文献   

4.
舰船运动姿态预报可更好地保障舰船各项作业的顺利进行,提高航行安全性。该文从频域角度仿真随机风浪,据此仿真舰船运动。考虑到舰船运动姿态时域上的非线性、非平稳特点,采用多层AR模型进行舰船运动姿态预报,并根据仿真案例进行预报检验。多层AR方法能有效提高极短期预报的精度。  相似文献   

5.
运动预报是部分舰船系统的重要组成部分。为了有效地解决这一问题,文章提出了一种基于海浪峰值频率估计的自适应舰船运动预报方法。在舰船运动与海浪激励的建模基础上,建立了基于最小二乘估计的自复位海浪峰值频率估计器。采用自回归移动平均(ARIMA)模型拟合方法预报舰船运动,并通过海浪峰值频率估计值自适应调节ARIMA模型的采样周期,提高了复杂海况下对舰船运动的预报能力。该方法与常规ARIMA模型方法、反向传播神经网络方法的仿真对比结果表明了该方法在解决舰船动态预报问题上的良好精度和鲁棒性。  相似文献   

6.
船舶运动极短期预报研究   总被引:4,自引:1,他引:3  
本文通过对两艘有航速情况下的船舶运动实测数据的分析,试图寻求一种准确程度较高的极短期预报模型。该文共分两部分,第一部分利用AR模型导出多级AR模型,预报精度明显提高。在对运动瞬时值预报中,利用包络对结果进行修正,精度有所改进;第二部分利用人工神经网络导出了包络的预报模式,预报精度明显高于AR模型。  相似文献   

7.
舰船的短期运动预测有助于舰载武器系统的校准,从而提升武器系统的打击精度,由于舰船在海浪作用下持续不断做非线性多自由度运动,因此,必须建立一种非线性预测模型进行舰船目标运动的准确预报。本文介绍一种非线性灰度理论,结合该理论对舰船的短时纵摇角度等运动进行预测建模。结果表明,基于灰色系统的舰船目标运动预报有较高的精度。  相似文献   

8.
传统的船舶横向运动短期姿态预报数学模型存在着预报性能低的缺陷,为此提出船舶横向运动短期姿态预报数学建模可行性研究。采用平均滤除法对船舶横向运动数据中的不良数据进行去除,完成船舶横向运动数据准备,将得到的船舶横向运动数据进行归一化处理,适应预报函数的需求,将得到的归一化的船舶横向运动数据输入到BP神经网络算法中完成船舶横向运动短期姿态的预报,实现了船舶横向运动短期姿态预报数学模型的建立。通过实验得到,构建的船舶横向运动短期姿态预报数学模型预报误差比传统模型低了21.41%,预报时间比传统模型高出3.25 s,充分说明构建的船舶横向运动短期姿态预报数学模型具备良好的可行性与预报性能。  相似文献   

9.
具有艏前波观测量的大型舰船姿态运动极短期预报   总被引:6,自引:0,他引:6  
本文提出了具有艏前波观测量时大型舰船姿态运动建模的预报方法,仿真计算表明,该方法具有满意的预报精度。最后,将该方法与通常的AR方法进行了比较。  相似文献   

10.
文章基于混沌动力系统相空间重构理论,利用关联维数法和最大Lyapunov指数法,对船舶运动时间序列的混沌特性进行了判定。并利用RBF神经网络较强的非线性映射功能,结合相空间重构理论建立了船舶运动极短期直接多步预报模型。实例预报结果表明,所建立的预报模型应用于船舶运动极短期预报取得了令人满意的预报精度,预报时间可达10 s。  相似文献   

11.
Appropriate modeling of roll damping is one of the key issues in accurately predicting ship roll motion. The difficulties in modeling roll damping arise from the nonlinear nature of the phenomena. In this study, we report a new effort in modeling the bilge keel roll damping effect based on the blocking mechanisms of an object in the potential flow. This effect can be implemented as a component of appropriate ship motion models. We used our digital, self-consistent, ship experimental laboratory (DiSSEL) ship motion model to test its effectiveness in predicting ship roll motion. Our numerical experiment demonstrated clearly that the implementation of this roll damping component improves significantly the accuracy of numerical model results (the results were compared with ship experiment data from the Naval Surface Warfare Center, Carderock Division, Maneuvering and Seakeeping Facility).  相似文献   

12.
In this paper, Neural Networks (NNs) are used in the modeling of ship maneuvering motion. A nonlinear response model and a linear hydrodynamic model of ship maneuvering motion are also investigated. The maneuverability indices and linear non-dimensional hydrodynamic derivatives in the models are identified by using two-layer feed forward NNs. The stability of parametric estimation is confirmed. Then, the ship maneuvering motion is predicted based on the obtained models. A comparison between the predicted results and the model test results demonstrates the validity of the proposed modeling method.  相似文献   

13.
In this paper, Neural Networks(NNs) are used in the modeling of ship maneuvering motion. A nonlinear response model and a linear hydrodynamic model of ship maneuvering motion are also investigated. The maneuverability indices and linear non-dimensional hydrodynamic derivatives in the models are identified by using two-layer feed forward NNs. The stability of parametric estimation is confirmed. Then, the ship maneuvering motion is predicted based on the obtained models. A comparison between the predicted results and the model test results demonstrates the validity of the proposed modeling method.  相似文献   

14.
内河航道船舶航行操纵平面二维数值模拟初步研究   总被引:1,自引:0,他引:1  
船舶航行操纵数学模型包括水流数学模型和船舶航行数学模型,其中水流数学模型是船舶航行模拟的基础。基于船舶航行操纵数学模型的基本原理,研究开发了船舶航行操纵平面二维数学模型,其中水流数学模型采用贴体坐标系下的平面二维水流数学模型,采用有限体积法对水流基本控制方程进行了离散,在求解过程中采用了欠松弛技术和逐线迭代法,船舶航行数学模型采用比较流行的"组合型"水动力模型,并采用有限差分法离散求解船舶运动方程。根据实船或船模在静水条件及均匀流条件下的航行试验资料,对所建立的船舶航行操纵数模进行了验证和参数率定,结果表明该船舶数模能够正确模拟船舶的航行操纵性能。  相似文献   

15.
In the present study a novel modeling approach is presented to solve the combined internal sloshing and sea-keeping problem. The model deals with interesting effects arising due to the coupled interaction between the sloshing in partially filled containers of several geometries and the ship motion. The study is very important for the liquid cargo carrier operating in rough sea or under different environmental conditions. The resulting slosh characteristics that include transient pressure variation, free surface profiles and hydrodynamic pressure over the container walls have been reported in this study. In addition, the effects of coupled ship response and sloshing on ship motion parameters have also been investigated. The equations of motion of fluid, considered inviscid, irrotational, and partially compressible, are expressed in terms of the pressure variable alone. A finite difference-based iterative time-stepping technique is employed to advance the coupled solution in the time domain. Several parameters of interest, including the container parameters, level of liquid, thrusters modeling and some important environmental factors are investigated.  相似文献   

16.
船舶列队是未来水路运输的重要方式。分析船舶列队协同控制的特点和原理;从船−岸协同交互、列队控制模型、列队运动控制、列队典型应用等4个方面分别进行现状分析与梳理。总结当前船舶列队控制技术瓶颈,包括人机共驾控制、列队控制运动不确定性建模、列队协同控制一致性、通信受限下船舶列队鲁棒控制及一致性控制等。最后,指出未来的船舶列队协同控制发展,应重点解决基于数据驱动与机理融合的列队运动建模、基于生物群体机制的船舶列队控制、基于分层控制的船舶列队控制等关键问题。  相似文献   

17.
应用三维时域水动力理论,以挪威船级社(DNV)的WASIM程序系统作为主要工具,分析研究了一条在国际航线上航行的某一集装箱船的水动力特性,包括船体运动与波浪诱导载荷的规律,给出了不同航速下的船体运动特性和剖面诱导载荷百年一遇长期预报结果,深入分析了船体的航速效应,为船体设计中船体波浪载荷设计提供了参考依据。  相似文献   

18.
[Objective]To investigate ship motion and load responses in realistic 3D waves and overcome the limitations of the traditional 2D wave assumption, this paper develops a method for predicting ship motion and load responses in short-crested waves. [Method]The long- and short-term responses of ship motion and load in long- and short-crested waves are numerically predicted using the spectral analysis and statistical probability methods, respectively. The influence of directional function on ship response is also numerically analyzed. Moreover, tank model tests and a large-scale model sea trial are comparatively conducted to validate the difference between ship response and statistics in long- and short-crested irregular waves. [Results]The results show that when navigating against the waves in the same sea condition, the long-crested wave assumption overestimates the statistical mean value of ship load response, but underestimates extreme load in real seas. For long-crested waves, the ship motion and acceleration power spectrum is concentrated around a certain frequency band. [Conclusion]Ship motion and load responses in realistic 3D waves are significantly different from those in 2D long-crested waves. The directional function of short-crested waves also has a significant effect on ship motion and load responses. © 2023 The Author(s).  相似文献   

19.
康伟  褚建新  黄辉  顾伟 《中国造船》2012,(1):107-116
根据船舶分离型运动建模方法,分析了可回转双桨船舶的运动规律及其在船舶纵荡、横荡和艏摇三个自由度上的作用力,建立可回转双桨作用下的电力推进船舶的推进与回转运动模型,导出船舶运动线性响应方程。通过数值仿真,验证了可回转双桨电力推进船舶的推进与回转运动模型的准确性。  相似文献   

20.
舰船运动的一种改进经典谱估计方法   总被引:3,自引:1,他引:2  
通过对经典谱估计各种方法的性能分析与比较,并结合实际加以改进,进而提出了针对舰船运动的切实可行的谱估计方法,通过仿真,获得了比较令人满意的结果。此方法在提高舰船运动建模及预报的精度等方面,具有一定的实用价值。  相似文献   

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