Method for determining image centroid of small irregular celestial body for deep space autonomous navigation

Abstract

The invention relates to a method for determining an image centroid of a small irregular celestial body for deep space autonomous navigation. According to the method, a centroid coordinate system is determined according to a small celestial body three-dimensional shape model generated by ground data, the Hu seven-type normalized constant central moment of the small celestial body in different directions is built according to imaging in different directions, the centroid correction factor corresponding to the current form center is given in the direction, and a model base is formed; the contour of the small celestial body is extracted according to the current time shot image; the first-order moment of a contour binary image is calculated, i.e. the form center is used as the center, and the Hu normalized one-type and two-type second-order constant central moment is calculated; the second-order central moment is calculated, the subsequent matching operation is carried out, when the matching is not successful, the three-type to seven-type third-order central moment is continuously calculated, and then, the complementary matching is carried out; and the calculated central moment is matched with the central moment stored in the model base, when the similarity meets the set threshold condition, the matching of the current position is considered to be completed, and the form center of the current form center is modified by the centroid factor. The method has the advantage that the consistency of the centroid output in different directions is guaranteed.

Description

technical field [0001] The invention relates to a method for determining the center of mass of an irregular small celestial body image for deep space autonomous navigation, and belongs to the field of image processing in aerospace technology. Background technique [0002] Small celestial bodies are the leftover matter after the formation of the solar system and are an important part of the solar system. They maintain the original state at the origin of the solar system and contain important information about the formation and evolution of the solar system. The study of small celestial bodies has very important scientific significance for revealing the origin and evolution of the solar system and exploring the origin of life, and has important practical significance for exploring and developing the solar system and responding to possible impact events on the earth. [0003] But small celestial bodies are not necessarily similar to spheres, they may be irregular geometric bod...

AI Technical Summary

Problems solved by technology

[0004] At present, there are many domestic research methods using the pointing information of small celestial bodies for navigation, but most of them assume that the pointing information of small celestial bodies has been obtained, and the specific acquisition method is unknown

In the research of foreign literature, the center of the small celestial body is defined as the center of the largest bright spot in the image, and then compensated, but the selection and calculation method of the compensation coefficient are not introduced in detail

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