The Theory And Methods Of Three-dimensional Terrain / Scene Matching And Registration

The concept of three-dimensional terrain matching appears in the 70 s. In the mid-80 s, it got rapid developed, and in the early 90 s it began to be applied to the construction of national defense. Until now, with the continuous development of science and technology and the improvement of the national defense requirements, as one of the main technical problems in the field of military applications, three-dimensional terrain matching occupies the important position in the field of the terrain matching aided navigation. Also because of its importance in the national defense science and technology, in recent years it has been researched at a high heat. In the mean time, with the development of three-dimensional terrain matching, its concept and matching methods are constantly changing. For example, the traditional three-dimensional terrain matching refers to terrain height matching. With the improvement of terrain matching requirements, now most three-dimensional terrain matching combines scenes, called three-dimensional terrain scene matching.Firstly, this paper summarizes the research status at home and abroad on the three-dimensional terrain matching, focusing on the analysis and research on the traditional height-based three-dimensional terrain matching method. For the problem that the height-based three-dimensional terrain matching method always can not match imprecisely when the terrain height dramatic ups and downs or did not change significantly, this paper proposed a three-dimensional terrain matching algorithm based on the features of the terrain surface texture. The algorithm firstly obtains the two-dimensional orthographic projection of a realistic three-dimensional terrain, then calculates out the direct matching relations between the reference terrain and the terrain to be matched based on the matching results of the two-dimensional projection, and finally draws the two terrains which have already established the matching relations. Many experiments using the proposed algorithm have been done on lots of different terrains in this paper, the results show that the proposed algorithm is able to match and accurately position the terrain areas.Secondly, on the basis of study of the line features present in the scene, this paper firstlydetects the roads in different scenes, and on this basis proposes a method for fast scene matching based on roads. This method can improve the matching speed, specifically in the part of feature detection stage, the feature extraction time has greatly reduced.Finally, according to the proposed algorithm, three-dimensional terrain/scene match and registration software is developed, and it is stable. On the basis of three-dimensional terrain modeling and visualization, the software can match and position the local terrain area. It also has the function of global terrain matching and terrain reconstruction when partial overlapping areas exist. In addition, by extract the road linear features, the software can achieve fast scene matching based on road features.