Study On Detection Of Lunar Impact Craters Based On DEM And Digital Terrain Analysis Method

With the development of the lunar exploration of Chang'e series in our country,the research on the lunar surface topography has gradually become a hot spot.As one of the most representative geomorphological units on the moon's surface,the research of the impact crater on the lunar surface is of great significance to the study of the ex-ploration of the evolution history of the lunar surface,the formation of lunar surface topography,and the early volcanic eruption.In addition,placement for lunar probe is also closely related with lunar surface topography study.The determination of the real shape and position of the lunar impact craters has some reference value for the selec-tion of the detector landing points.The real boundary reveals the order of impact,and the order of impact reflects the history of the evolution of the craters.Currently,most mainstream detection algorithms for lunar impact craters are based on circular to real-ise the detection of craters,but these methods counter difficulty in expressing the real shapes in an accurate manner.It is difficult to conduct an advanced analysis,such as characteristic and spatial heterogeneity analyses of the lunar surface.In this article,the lunar surface topography data obtained from the "Chang'e ?"and "Lunar Reconnaissance Orbiter"(LRO)were taken as the main data source.Through the analysis of spatial characteristics,the types of craters were defined.Based on the morphological characteristics and terrain features,the extraction index based on the crater features was established.On the basis of that,the digital terrain analysis algorithm was used to detect the real boundary of the lunar surface crater,in order to provide a valuable reference for the research and detection of the lunar sur-face topography.The main research contents and achievements of this article are as follows:(1)Based on the basic shape of impact crater,the basic components of impact crater such as crater rim,crater bottom,crater wall,central peak and sputter sediment were presented.The spatial features,morphological features and topographical features of lunar impact crater were analyzed,and the impact craters were divided into dispersal craters and complex craters based on the spatial relationship characteristics,which laid the foundation for the construction of extraction index system based on the char-acteristics of the crater.(2)Based on the above analysis of the characteristics of the lunar craters,the applica-bility of the characteristic index in describing the impact craters were evaluated,the indexes that followed the morphological differences and were conductive to the de-tection of impact craters were selected to construct the index system based on the characteristics of the crater for boundary detection,the way for the subsequent extrac-tion of craters was paved.(3)Taking the advantages of DEM in the study of object recognition,this article mainly focused on the lunar impact craters,presented an innovative algorithm for de-tecting lunar craters based on DEM and digital terrain analysis.A set of evaluation index system for crater detection algorithms was also designed to evaluate the preci-sion of detection results.From the experimental results for detection and comparing,it can be found that the proposed algorithm could extract the real boundary of the crater on the lunar surface and have high accuracy of extraction.At the same time,the ex-trated impact craters could enrich the existing catalog of lunar impact craters.The study of craters provided new technical support.