8 research outputs found

    China Maritime Report No. 29: PLAN Mine Countermeasures: Platforms, Training, and Civil-Military Integration

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    The People’s Liberation Army Navy (PLAN) has made incremental progress in its mine countermeasures (MCM) program in recent years. The PLAN’s current inventory of about 60 MCM ships and craft includes classes of minehunters and minesweepers mostly commissioned in the past decade as well as unmanned surface vessels (USVs) and remotely operated vehicles with demonstrated explosive neutralization capability. Despite the addition of these advanced MCM platforms and equipment, experts affiliated with the PLAN and China’s mine warfare development laboratory have serious reservations about the PLAN’s current ability to respond to the full range of likely threats posed by naval mines in future contingencies. The PLAN’s MCM forces are currently organized for operations near China’s coastline, but writings by Chinese military and civilian experts contend that to safeguard Beijing’s expanding overseas interests, the PLAN must develop MCM capabilities for operations far beyond the First Island Chain. PLAN and civilian mine warfare experts have proposed various solutions for offsetting perceived shortcomings in the PLAN’s MCM program, including the development of autonomous USVs and unmanned underwater vehicles (UUVs), deployment of modularized MCM mission packages on ships such as destroyers and frigates, and mobilization of civilian assets such as ships and helicopters in support of MCM operations. Although there appears to have been little to no adoption of these proposed solutions to date, the PLAN recognizes MCM as one of its biggest challenges, and one can expect the PLAN to continue making measured progress in its MCM program in the years ahead.https://digital-commons.usnwc.edu/cmsi-maritime-reports/1028/thumbnail.jp

    Research on the methods of ship\u27s autonomous collision avoidance in complex environment

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    Prediction Method Research on Motion Attitude of UnmannedSemi - submersible Vehicle

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    针对半潜式无人艇运动过程中首摇和纵摇受外界环境影响较大,影响运动控制系统的有效性的问题,采用时间序列分析预报方法和灰色预报方法,进行运动姿态预报方法研究。根据一般工况下半潜式无人艇的首摇和纵摇数据建立了AR模型和GM(1,1)模型,并进行了实时预报仿真及对比。仿真结果表明,AR模型和GM(1,1)模型对首摇和纵摇预报的整体效果良好。通过比较,AR模型预报的整体效果都优于GM(1,1)模型。AR模型对于半潜式无人艇运动姿态的预报具有一定的适用性,是一种可行的方法

    基于数据驱动的遗传算法的无人艇路径规划研究

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    遗传算法(GA)是无人艇路径规划系统中的一种有效方法,为了克服该算法易陷入局部最优早熟和收敛速度慢等缺陷,在不增加算法复杂度的前提下,基于数据驱动线性动态交叉策略提出了一种能够在最短时间内自适应动态调整控制参数的改进遗传算法(LCPGA)。与传统的遗传算法相比,LCPGA增加了种群多样性,能更有效地避免陷入局部最优,并提高了路径规划的精度、稳健性和收敛速度。仿真实验和无人艇现场试验验证了该算法具有更优良的性能,该算法可为无人艇路径规划提供一定的应用价值

    一种无人艇的规划测绘方法、装置及系统

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    本发明公开了一种无人艇的规划测绘方法、装置及系统。所述规划测绘装置包括信息获取单元以及覆盖测绘单元。所述规划测绘系统包括规划测绘模块、无人艇以及用户交互模块。通过栅格地图以及实时更新的相邻栅格列表显示测绘进度,并通过预设的外螺旋覆盖算法以及预设的转弯优先级代价启发函数,该规划测绘方法、装置及系统不仅提升死区逃离计算的效率,并实现测绘区域覆盖任务的可视化

    Research and Design of Light Electro-optical Stabilized Platform

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    无人艇在海洋环境侦察、扫雷、港口保护、海洋科考等领域具有广阔的应用前景,越来越受到大家的关注。无人艇上通常搭载有摄像机、热像仪等光电传感器,由于受到无人艇在海洋中的摇荡运动和艇载设备引起的动载荷的影响,容易造成视场目标丢失和成像模糊。极大地影响了光电传感器的效能,考虑采用光电稳定平台来克服动载荷对光电传感器的影响。光电稳定平台基于陀螺稳定原理,能够克服动载荷引起的视轴晃动。针对某无人水面艇桅杆较高、负载对航行体姿态影响较大的特点,设计了一两轴两框架轻型光电稳定平台。本文首先利用能量谱的方法对无人艇在随机波浪下的运动特性进行了分析,获得了无人艇摇荡运动仿真曲线。采用虚拟仿真技术建立简化的两轴两框架稳定平台模型,对稳定平台由无人艇摇荡运动引起的框架运动进行了分析,获得了需要补偿的稳定平台框架角运动补偿范围。对光电传感器的作用距离和平台的稳定精度也进行了分析。确定了光电稳定平台的总体设计指标,对相关传感器进行了选型。 然后,根据光电稳定平台的总体设计指标对轻型光电稳定平台进行了详细结构设计。主要包括方位框的驱动机构和俯仰框架的驱动机构。考虑了其驱动、测速、制动、防电线缠绕等问题。由于总体设计指标中,体积和重量都很小,需要考虑在较小的空间布置较多的部件,因此在设计时如何减小结构占用空间是一个主要的考虑因素。对光电稳定平台的驱动部件和支撑部件的载荷进行了分析,根据其载荷对力矩电机进行了选型,对轴承和驱动轴进行了设计校核,并对法兰、基座等形状复杂结构利用有限元分析进行了强度和刚度校核。 最后,分析了稳定平台框架谐振频率对系统伺服性能的影响,对稳定平台中较为关键的方位框架,进行了动态特性分析。为进一步降低框架重量,以方位框架的谐振频率和重量为目标进行了多目标优化。本文设计的光电稳定平台体积小、重量轻,并且满足无人水面艇的光电传感器探测距离需求。文中设计光电稳定平台的结构对于设计小型伺服驱动结构有一定的借鉴意义
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