RTK GPS在超短基线声学定位系统安装校准中的应用

超短基线（uhra short base line,USBL）声学定位系统的换能器安装是具有一定方向性的,但是,在安装过程中,不能保证换能器方向与船艏方向严格一致,必然存在不可忽视的系统误差,影响了测量精度;因此,必须通过校准消除系统误差。本文应用高精度RTKGPS实现了换能器安装方向的校准,取得了满意的结果。     

基于倒置声学基阵的INSUSBL组合导航算法研究

文中关注水下潜航器导航定位时,电磁波传播途径中能量衰减、惯导系统长航时积累误差以及提高水下潜航器定位精度等问题。基于倒置的超短基线声学基阵,分析声波往返传播时间(RTT)、平面波近似方法和USBL导航解算方法及其坐标转换过程,结合INS误差方程,建立INS/USBL松组合模型。为进一步提高系统精度、动态性能和抗干扰性,考察USBL的原始斜距、斜距差以及声学基阵的空间分布信息,提出基于USBL原始输出信息的INS/USBL紧耦合组合导航方法。通过MATLAB仿真对导航算法进行验证,结果表明两种算法能充分抑制纯惯导误差随时间积累问题,且有效地估计出姿态、速度和位置误差角;其中紧耦合方法状态估计误差最小,导航参数精度相对松组合提高30%以上,对于提高水下载体导航定位精度、海洋探测具有重大意义。     

Target Deployment and Retrieval Using JIAOLONG Manned Submersible in the Depth of 6600 m in Mariana Trench

China''s 7000 m manned submersible JIAOLONG carried out an exploration cruise at the Mariana Trench from June to July 2016. The submersible completed nine manned dives on the north and south area of the Mariana Trench from the depth of 5500 to 6700 m, to investigate the geological, biological and chemical characteristics in the hadal area. During the cruise, JIAOLONG deployed a gas-tight serial sampler to collect the water near the sea bottom regularly. Five days later, the sub located the sampler in another dive and retrieved it successfully from the same location, which is the first time that scientists and engineers finished the high accuracy in-situ deployment and retrieval using a manned submersible with Ultra-Short Base Line (USBL) positioning system at the depth more than 6600 m. In this task, we used not only the USBL system of the manned submersible but also a compound strategy, including five position marks, the sea floor terrain, the depth contour, and the heading of the sub. This paper introduces the compound strategy of the target deployment and retrieval with the practical diving experience of JIAOLONG, and provides a promising technique for other underwater vehicles such as manned submersible or Remote Operated Vehicle (ROV) under similar conditions.     

Quantification of Spatial and Thematic Uncertainty in the Application of Underwater Video for Benthic Habitat Mapping

This study presents an analysis of the application of underwater video data collected for training and validating benthic habitat distribution models. Specifically, we quantify the two major sources of error pertaining to collection of this type of reference data. A theoretical spatial error budget is developed for a positioning system used to co-register video frames to their corresponding locations at the seafloor. Second, we compare interpretation variability among trained operators assessing the same video frames between times over three hierarchical levels of a benthic classification scheme. Propagated error in the positioning system described was found to be highly correlated with depth of operation and varies from 1.5m near the surface to 5.7m in 100m of water. In order of decreasing classification hierarchy, mean overall observer agreement was found to be 98% (range 6%), 82% (range 12%) and 75% (range 17%) for the 2, 4, and 6 class levels of the scheme, respectively. Patterns in between-observer variation are related to the level of detail imposed by each hierarchical level of the classification scheme, the feature of interest, and to the amount of observer experience.     

高精度水下定位的一种实现方案

提出了一种运用GPS和超短基线等设备实现潜器水下高精度定位的方案,给出了完整的定位解算数学模型,并进行了误差仿真分析。     

单应答器导航深海试验

布放于海底的单只应答器能够为安装有超短基线的水下潜器定位导航。介绍了单应答器导航的基本原理,简要分析了各种可能误差源对导航精度的影响。为了验证系统在深海中的工作性能,在中国南海进行了深海试验并给出了结果。     

水下地貌调查测量精度提高方法研究

海洋调查中,为确保调查信息与实际位置相匹配,提高调查成果的可信度,必须提高作业船拖曳调查设备的定位精度。论述了基于超短基线（USBL）水声定位与差分全球定位系统（DGPS）组合的新方法,消除了因作业船频繁变向、潮流的流向及流速等造成的调查设备位置的测量误差,成功地解决了调查信息错位,提高了海底地貌调查的定位测量精度,实用性较强。     

超短基线系统水下定位误差分析

介绍了超短基线定位的研究现状和定位精度,分析了超短基线水下定位系统误差的来源、各种数据融合过程中的误差和定位精度,最后提出了提高水下定位系统精度的几点措施。     

深海超短基线声学定位系统计算目标水平距离的一种新方法

对深海环境中工作的潜器或设备载体进行定位测量是深海调查的重要任务之一，本文基于射线声学原理对超基线声学定位系统的定位数据提出了一种迭代处理算法，能够得到非常精确的水平距离测量结果，这种方法对于大洋调查的深拖系统和其他下水设备定位有重要的现实意义。     

超短基线系统定位精度改进方法

超短基线是一种常用的水声定位技术,与其它基线相比,超短基线定位系统基线基阵尺寸小,易于安装。由于在远距离误差发散快,超短基线作用距离不远,其远距离定位精度也不高。为了满足深海作业需要,提高超短基线远距离的定位精度,提出改进超短基线定位精度的两种方法,一种方法是通过改进基阵阵形,从而加大基阵孔径提高定位精度;另一种是通过使用宽带信号测向,采用相关峰内插时延估计的方法。经计算机仿真,通过两种方法改进后的超短基线系统定位精度都得到不同程度的提高。