Real-time renewal of the digital map for local government by using remote sensing and RTK-GPS

Abstract

Much local government has been using a large scale digital map with Geographic Information System (GIS). However, the updating method of a map is not established yet. The purpose of this study is the real-time renewal of the digital map for local government by using Remote Sensing and RTK-GPS. This concept was defined as REAL TIME GIS. This system has the problem that RTK-GPS measuring data is Japanese Geodetic Datum 2000 (JGD2000) of WGS-84, but most of the digital maps of local government are still Tokyo Datum of old geodetic system. It is necessary to transform an old geodetic system to a new one. In this study, the coordinate transformation methods were compared Affine Transformation with TKY2JGD. Moreover, the number and arrangement of control points were changed, coordinates were converted by Affine Transformation. In this paper, the parameters which were calculated by Affine Transformation were called “High-Accuracy Regional Parameter (HARP)”. As a result, TKY2JGD has a maximum 15cm error. Affine Transformation has 2cm errors using 4 control points at the corner of unit. It is suggested that the process of REAL TIME GIS and HARP should be introduced to the work of local government.