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自动表面船用于岛礁水深测绘 总被引:1,自引:0,他引:1
岛礁具有重要的地位,然而对其附近水深的调查手段却不充分。比较了几种水深测绘手段的优缺点,设计了一种小型自动表面船用于岛礁水深测绘。该表面船底部安装声学测深仪,具备自动定位、导航与运动功能;其尾部安装两个电动推进器提供动力,通过独立控制两个推进器的转速,可实现船体的前进、后退和转向;利用无线电与岸基单元进行数据通讯。根据不同水深测绘条件,该船可以用三种控制方式进行水深测量:直接控制、间接控制和自主控制。测量数据实时传输到岸基单元,并自动存储于船载存储单元。初步试验结果表明,设计的自动表面船测量系统具有可行性。 相似文献
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沿岸水深测量技术方法的探讨 总被引:4,自引:3,他引:4
对沿岸水深测量各种技术方法进行了探讨,对各种技术方法的特点进行了阐述,根据海岸带图测量水域为沿岸浅水区的特点和当前测深技术及装备的情况,对水深测量方案的选择给出结论。 相似文献
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中尺度涡在大洋中普遍存在,研究发现其能量比大尺度海洋环流的能量大一个量级,在海洋物质能量输运和全球气候变化中起着重要的作用。受观测条件限制,目前对中尺度涡的观测主要通过卫星高度计实现,只能从海面高度来推算中尺度涡大小、分布、强度及其伴随的水体和能量输送,而卫星高度计对中尺度涡垂直结构特征认识不足,也导致了对中尺度涡所引起的上层海洋能量、热量输送估计误差偏大。目前对中尺度涡三维结构观测认识不足,展望未来将会出现基于无人船平台的大洋中尺度涡三维结构自动观测系统,该平台将集成自动水下剖面观测功能等先进技术,以便观测中尺度涡的垂直结构特征及其时空变化特征,进而可对中尺度涡带来的物质和能量输送进行系统认识。 相似文献
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A trajectory-cell based method was proposed for unmanned surface vehicle (USV) motion planning to combine the expression of the dynamic constraints and the discretization of the search space. The dynamic constraints were expressed by the USV trajectories produced by the mathematical model. The search space was performed by the discretization rules with the consideration of the path continuity, the search convenience and the maneuvering simplification. Therefore, the trajectory-cells were the discretized trajectories, which made the search space meet the USV dynamic constraints, and guaranteed the final spliced path continuous. After abstracting the characteristics of those cells, the available waypoints and headings were represented as the search indexes. Finally, a trajectory-cell based path searching strategy was proposed by determining the cost function of the A* algorithm. The results showed that the proposed algorithm can plan a practical motion path for the USV. 相似文献
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水面无人艇(USV,Unmanned Surface Vehicle)具有吃水浅、灵活机动、安全高效的特点和优势,日益成为浅水调查的重要手段。对于常规船只和考察人员不能到达的浅水环境的调查,无人艇具有填补甚至替代的价值和意义。C-Worker 4水面无人艇平台搭载了多波束测深、侧扫声呐、浅层剖面声学系统,运用脉冲同步控制和发射频率差异化配置的方法实现数据同步采集,旨在提高调查效率、优化调查方法和节约成本。基于2019年在海南岛澄迈湾1.2~22 m浅水环境的调查数据,处理和分析评估表明其采集数据可靠性高,能清晰识别海底沙波、波纹、礁石、埋藏河道、港池、航道、拖痕等微地貌单元。研究证实水面无人艇搭载多源声学系统同步测量可提供精细、立体、可靠的海底地貌基础资料,服务于海岸带地质调查、资源开发、工程建设、水运交通和国防安全等。 相似文献
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Considering the dynamic changes of unmanned surface vehicle (USV) in berthing tasks, the planning and control modes are divided into two phases: the remote phase and the terminal phase. According to the main influencing factors of the two phases, an improved artificial potential field method is proposed to complete autonomous berthing trajectory planning based on the analysis of environment constraint, berth point constraint and USV’s dynamics constraint. Combining with the dynamic characteristics and control objectives at different phases of berthing and analyzing the fuzzy rule regulation strategy of USV’s heading and speed control, an improved adaptive fuzzy PID control method is proposed to solve the control problem of USV, which is influenced by weak maneuver, large disturbance, limited water area and strong shore effect. Finally, the comparative test of berthing simulation verifies the superiority of the proposed control method. The autonomous berthing field experiment is completed based on the "Dolphin-I" small USV. It verifies the validity and feasibility of the proposed autonomous berthing method. 相似文献
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卫星影像是监测海面漂浮绿藻的重要数据源, 但是混合像元的存在使得绿藻提取存在一定的误差。想要实现近海区域底栖绿藻的精细监测, 需要解决绿藻亚像素覆盖度的问题。本文以厘米级分辨率无人机数据的绿藻提取结果为基准, 通过分析Landsat卫星影像绿藻光谱, 建立绿藻亚像素覆盖度与多种植被指数和多个特征波段反射率的反演模型。结果表明, 蓝、绿、红波段反射率与绿藻亚像素覆盖度呈现较好的线性关系, 随着绿藻亚像素覆盖度递增, 蓝、绿、红波段反射率的值均递减。将蓝、绿、红波段的三种绿藻亚像素覆盖模型进行验证, 发现绿波段反射率所建立的反演模型具有更高的准确性, 决定系数、均方根误差、平均相对误差分别为0.92%、0.07%、10.85%。本文所建立的模型可以估算大型绿藻亚像素覆盖度, 实现Landsat卫星影像对大型绿藻的精细监测。 相似文献
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针对海岸线区域地形复杂和卫星遥感影像分辨率的不足,精度难以满足大比例尺成图要求,以及常规解译方法的局限性,选取青岛小岛湾海岸线为研究区,以无人机(UAV)遥感影像为基础数据,提出一种面向对象的海岸线提取方法,结合现场实测验证,开展了人工海岸线和砂质海岸线识别的应用实验。结果表明:人工海岸线和砂质海岸线概率边缘指数(PRI)分别为0.97和0.88,边缘定位误差(BDE)分别为4.33和2.84,提取的人工海岸线和砂质海岸线与实测海岸线结果整体上匹配较好,仅在局部细微处存在微小差异。本文提出的方法可快速有效地获取海岸线信息,其精度能够满足海岸线动态变化监测的需求,可在海岸线资源管理中推广应用。 相似文献
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Based on the model-free adaptive control (MFAC) theory, the heading control problem of unmanned surface vehicles (USVs) with uncertainties is explored. First, as a USV’s heading subsystem does not satisfy the quasilinear assumption of the MFAC theory, a new type of input and output information fusion MFAC, i.e., the IOIF–MFAC algorithm is proposed. The novel algorithm proposed herein renders the MFAC theory applicable to the heading control of USVs. Next, the input and output information of the heading subsystem, namely the rudder angle and heading angle, are combined, and the data model of the heading subsystem is subsequently deduced using a compact format dynamic linearization method. Based on which, the stability of the control system is proved. Finally, the effectiveness and practicability of the IOIF–MFAC algorithm are verified by simulation and field experiments through the “Dolphin IB” test platform developed by our group. 相似文献