Usability evaluation algorithm of sea area landmark

海域地标点可用性评估算法

¹ School of Automation, Northwestern Polytechnical University, Xi'an 710129, China
² AVIC Xi'an Flight Automatic Control Research Institute, Xi'an 710065, China

Received: 19 April 2021

Abstract

The landmarks encountered by a flight vehicle in its scene matching navigation are insufficient and distributed unevenly, thus being unable to effectively assist in its inertial navigation system (INS). Therefore, this paper proposes a novel algorithm for sea area landmark usability evaluation based on the probability model. The algorithm defines three types of sea area landmarks and gives their matching method and strategy. The visible range of each sea area landmark is determined according to its relative relations between each position and all landmarks in flight area, flight altitude, flight speed, camera field of view angle and INS drift error. The matching probability of different types of landmarks at different flight altitudes is calculated. Then the observable probability of each landmark is reckoned to give the probability cloud of the sea area landmark usability. The simulation results verify the effectiveness of the algorithm. The sea area landmark usability evaluation results can provide bases for INS to effectively utilize landmarks to perform route planning and realize long-time flight and high-precision navigation.

摘要

针对飞行器在海域景象匹配导航(SMN)中可遇到的地标点较少且分布不均匀, 不能有效辅助惯性导航(INS)的问题, 提出了基于概率模型的地标点可用性评估算法。该算法定义了三类海域地标点, 给出了三类地标点的匹配方法和策略; 根据飞行区内每个位置与所有地标点之间的相对关系、飞行高度、飞行速度、相机的视场角以及INS漂移误差确定每个地标点的可见范围, 并结合不同类型地标点在不同飞行高度下的匹配概率, 计算得到每个位置的地标点可观测概率, 最终给出海域地标点可用性的概率云图。仿真结果验证了该算法的有效性。海域地标点可用性评估结果可为INS有效利用地标点进行航路规划, 实现长航时、高精度导航提供依据。