Autonomous underwater vehicle (AUV), as a new underwater operation platform, has been widely used in the field of ocean engineering. AUV underwater condition monitoring is an important guarantee for the safety and effective execution of AUV operations. To meet the requirement of real-time and high-precision underwater instantaneous velocity monitoring of AUV, this paper proposed an AUV instantaneous velocity estimation method. The method takes the target azimuth and Doppler shift as the observation information. It comprehensively uses the geometric relationship among the target azimuth, heading angle, radial velocity angle, and the physical relationship between Doppler and radial velocity to construct an AUV instantaneous velocity estimation model based on distributed dual acoustic observation nodes. We derive the analytical solution of AUV speed and heading angle and analyze the influence of each observation error on the estimation precision of the algorithm. The research and practical data processing results show that the proposed method can effectively estimate the instantaneous velocity of AUV. Compared with the traditional method based on position difference, it has the advantages of high estimation precision, is not limited by frame interval, and is adaptive to many kinds of motion modes. When AUV moves in a straight line at a uniform speed, the precision of speed estimation and heading angle estimation of the algorithm proposed in the paper is 0.506 m/s and 6.146°, which is equivalent to that of the traditional method based on position difference with 50 frame intervals.

中文翻译：

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基于方位角和多普勒频移的AUV瞬时速度估计方法

自主水下航行器（AUV）作为一种新型水下作业平台，已广泛应用于海洋工程领域。 AUV水下状态监测是AUV作业安全、有效执行的重要保障。为满足AUV水下瞬时速度实时、高精度监测的要求，提出一种AUV瞬时速度估计方法。该方法以目标方位角和多普勒频移作为观测信息。综合利用目标方位角、航向角、径向速度角之间的几何关系以及多普勒与径向速度的物理关系，构建基于分布式双声观测节点的AUV瞬时速度估计模型。推导了AUV速度和航向角的解析解，并分析了各观测误差对算法估计精度的影响。研究和实际数据处理结果表明，该方法能够有效估计AUV的瞬时速度。与传统的基于位置差的方法相比，该方法具有估计精度高、不受帧间隔限制、适应多种运动模式等优点。当AUV匀速直线运动时，本文提出的算法速度估计和航向角估计精度分别为0.506 m/s和6.146°，与传统基于位置差的方法相当50 帧间隔。