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相比于传统的长基线和超短基线等导航方式,水下单信标导航具有布放简单的优点,但其导航精度有待进一步提高。为此,提出了单信标导航的航路规划方案,通过泰勒级数展开推导了水平位置精度因子的表达式,并分析了导航点和声信标的相对几何位置关系对导航精度的影响,最终提出了航路规划方案。在此基础上,还提出了自主水下航行器(autonomous underwater vehicle,AUV)从其他位置接近最优航路的方法,包括两部分:一是建立以时延为观测量的滤波模型,利用滤波算法实时获取AUV的位置估计值;二是基于可观测度分析结果对最优航路接近过程的轨迹进行了设计。二者的结合使得AUV高效率且高精度地逼近最优航路。仿真证明了采用所提出的航路规划方案和最优航路接近方法可以提高导航精度,航路规划方案使得AUV位置估计的均方根误差近似为2 m。 相似文献
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《中国航空学报》2023,36(1):369-385
In information fusion, the uncertain information from different sources might be modeled with different theoretical frameworks. When one needs to fuse the uncertain information represented by different uncertainty theories, constructing the transformation between different frameworks is crucial. Various transformations of a Fuzzy Membership Function (FMF) into a Basic Belief Assignment (BBA) have been proposed, where the transformations based on uncertainty maximization and minimization can determine the BBA without preselecting the focal elements. However, these two transformations that based on uncertainty optimization emphasize the extreme cases of uncertainty. To avoid extreme attitudinal bias, a trade-off or moderate BBA with the uncertainty degree between the minimal and maximal ones is more preferred. In this paper, two moderate transformations of an FMF into a trade-off BBA are proposed. One is the weighted average based transformation and the other is the optimization-based transformation with weighting mechanism, where the weighting factor can be user-specified or determined with some prior information. The rationality and effectiveness of our transformations are verified through numerical examples and classification examples. 相似文献
365.
Warhead power assessment of the anti-ship missile plays a vital role in determining the optimal design of missile, thus having important strategic research significance. However, in the assessment process, expert’s judgement will directly affect the assessment accuracy. In addition,there are many criteria involved in the missile design alternatives. Some criteria with poor performance may be compensated by other criteria with excellent performance, and then it is impossible to find the truly opt... 相似文献
366.
The common design of serial civil aircraft, an important strategy of modern civil aircraft research and develop-ment, minimizes the whole life cycle cost of civil aircraft through asset reuse and resource sharing. However, the existing estimating model for the R&D cost of civil aircraft ignores the effects of common design, so the value estimated by estimating derivative models is significantly inconsistent with the actual one. To solve this problem, a novel assessment method for civil aircr... 相似文献
367.