Abstract: Three-dimensional laser scanning technology breaks through the traditional point-by-point measurement and achieves surface scanning data acquisition. Using high-speed laser scanning measurement, the three-dimensional coordinate data of the measured object surface can be obtained quickly, which has the characteristics of fast acquisition speed and abundant data acquisition. Moreover, the measurement distance is long and the data is accurate, and it is not restricted by the accuracy of geoid. In this paper, three-dimensional laser scanning technology combined with RTK technology is introduced. After measuring the locating point of scanner and the orientation point of rear-view target, the continuous three-dimensional coordinates in the panoramic range are obtained. Station scanning is set outside the field of vision to make the whole survey area free of loopholes and finally realize topographic map production.

Key words: 3D laser, topographic survey, DEM, topographic map, contour line