Extracting the split line of narrow and long patches is important for the generalization of land-use thematic data. There are two commonly used methods for extracting the split lines: One is based on Delaunay triangulation and the other is based on straight skeletons. However, it is difficult for the straight skeleton method to preserve geometric structure and topological consistency with the original data when dealing with polygons that have irregularity and complexity of junctions. Therefore, we propose an improved jitter elimination and topology correction method for split lines based on a constrained Delaunay triangulation. First, a split line adjustment algorithm based on the geometric structure of the polygon is proposed to eliminate the jitters. Second, a split line topology correction algorithm is proposed for nodes with degree 1 or degree 2, considering the boundary topological constraint. The reliability of the proposed method is verified by comparing it with the straight skeleton method using sample data and the superiority of the proposed method is verified by using actual data from China’s geographical conditions census in the Guizhou province.

This paper mainly introduces a Cirloc3D-vision location method used in robot tube plate welding. The visual position system uses a point laser sensor to measure the photo height, and can through three points to ensure a place to correct the camera posture. The captured image is used to extract the location information by the template matching method and searching the center of a circle's method. Then the information is sent to the robot and leads the robot to run to the specified position. Finally the welding gun at the end of the robot begins to perform the precision welding of the tube plate. This method is fast and accurate, so it can provide accurate position and orientation information for six axes industrial robots.

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ABSTRACT:With the globalization and rapid development every filed is taking an increasing interest in physical geography and human economics. There is a surging demand for small scale world map in large formats all over the world. Further study of automated mapping technology, especially the realization of small scale production on a large scale global map, is the key of the cartographic field need to solve.In light of this, this paper adopts the improved model (with the map and data separated) in the field of the mapmaking generalization, which can separate geographic data from mapping data from maps, mainly including cross-platform symbols and automatic map-making knowledge engine. With respect to the cross-platform symbol library, the symbol and the physical symbol in the geographic information are configured at all scale levels. With respect to automatic map-making knowledge engine consists 97 types, 1086 subtypes, 21845 basic algorithm and over 2500 relevant functional modules.In order to evaluate the accuracy and visual effect of our model towards topographic maps and thematic maps, we take the world map generalization in small scale as an example. After mapping generalization process, combining and simplifying the scattered islands make the map more explicit at 1:2.1 billion scale, and the map features more complete and accurate. Not only it enhance the map generalization of various scales significantly, but achieve the integration among map-makings of various scales, suggesting that this model provide a reference in cartographic generalization for various scales.

Building aggregation is an important part of large-scale map generalization. A triangulation-based building aggregation approach is proposed here. To improve aggregation's efficiency and accuracy, a six-feature filtering process is integrated to screen the triangles in the constructed constrained Delaunay triangulation (CDT). After filtering, the contours of retained triangles, as the connecting parts between buildings, are rectangularized and aggregated with buildings. Our experiments using diverse and real-world data have proved that this method is efficient and practical. 1