Map renewal technique by using collaboration of GPS, GIS and remote sensing

Much local government has been utilizing the large scale digital map with Geographic Information System (GIS). GIS will be able to efficiently work and to reduce mapping costs. However, the maintenance and renewal of a map database need much labors and time. However, the updating method of a map is not established yet and, there is little successful example. The purpose of this study is establishment to update of the large scale map for local government by using a REAL TIME GIS and its collaboration. REAL TIME GIS, which definition decided by our laboratory, is a technology that updates the digital map instantly by using RTK-GPS and the cellular phone. RTK-GPS data use Japanese Geodetic Datum 2000 (JGD2000) of WGS-84, but most of the digital map of local government is still Tokyo Datum of old geodetic system. In order to correspond with two kinds of data which have different geodetic system, it is necessary to transform coordinates. Geographic Survey Institute of Japan (GSI) opened a website for the conversion parameters and programs. GPS data is able to apply to digital map in small scale. However, Base Map and thematic map which has made by the large scale (1/500 or 1/1000) on the old geodetic system did not obtain sufficient accuracy. To solve these problems, our laboratory proposed High-Accuracy Regional Parameter (HARP) which changes from an old geodetic system to a new geodetic system.