Abstract: Gauss projection band changing of topographic map is an important work in the process of surveying and construction of engineering projects. It can be realized with the help of GIS software, but it is unable to solve the problem of projectionon arbitrary elevation plane.Moreover, it is easy to lose graphic information in the transformation of AutoCAD map and GIS map. In this paper, three common ellipsoid expansion Gauss projection band conversion methods are introduced, and DXF file coordinate direct modification method and graphic entity position attribute modification method are implemented on AutoCAD platform.The test results show that the method in this paper is rigorous in theory, the result of gauss projection band change is accurate and the software has strong practicability.

Key words: AutoCAD, Gauss projection band changing, offset elevation plane, ellipsoid expanding