A Utility Map Transformation System Based on Map Understanding

In recent years some electric power companies or gas suppliers have begun to use computerized utility map management systems. And there is a demand to share their utility data with each other. But that is difficult because their topographic maps, which give the base of equipment location, are different. So we developed an automatic transformation method of utility data, which transforms utility data for one system to another. This method enables utility map management systems to share their utility data with each other, even if their topographic maps are different. This transformation method consists of the following two stages ; 1) MAP UNDERSTANDING ; Topographic maps of two systems are analyzed and skeletons of geographic elements are extracted. 2) MODIFICATION OF EQUIPMENT LOCATION DATA ; Correspondence between skeletons of the two maps is established. And the equipment location is modsed according to i ts relative location to the neighboring skeleton. An experimental system is implemented and the effectiveness of this method is shown. 2. Outline of Utility Data Transformation 2.1 Needs of Utility Data Transformation Fig.1 shows examples of utility maps for electric power supply. In this case, utility maps consist of a series of topographic maps and a series of equipment location maps. A topographic map gives the location of geographic elements such as roads, houses, rivers, sidewalks, elc. -each of them expressed as a contour. An equipment location map shows the location of equipments such as electric poles, electric lines, transformers, etc. each of them expressed as a symbol. Overlaying the two maps, one can understand the relative location of the equipments to the geographic elements. (1) equipment location map