Accuracy Analysis For 3d Laser Scanning Technology For Modeling Ground

The traditional information expression way of surveying and mapping is based on twodimensional model. The three-dimensional model has intuitive and good visual effects, and can accurately and completely express the three-dimensional model information, but requires higher techniques in collecting and processing surveying and mapping information.3D laser scanning is the latest information collection technique of 3D information collection. It has been widely used since its introduction to mapping production areas in this century. This paper focuses on the study of scanning point cloud precision problems in digital terrain modeling process by using 3D laser scanning technology. Its main research contents and results are as follows:(1)Conducting deep discussion in engineering application of Leica Scanstation C10 scanner that use pulse ranging principle and its affiliated Cyclone software. Starting from the principle of a three-dimensional laser scanning technology, this paper makes specialized analysis about data processing, scanning data format conversion, data preprocessing and other content of Cyclone software.(2)In the three-dimensional laser scanning process, the conversion error of scanning coordinate system to engineering coordinate system is an important link that influencing accuracy and reliability of result.Because of the existence of the errors caused by control points themselves and measurement, the acquired coordinate conversion parameters based on control point target data registration often vary because of the different target selection of control points and lead to conversion error of engineering coordinate system. This phenomenon is called the coordinate conversion error in this paper. According to the conversion error of all known points in the survey area, establishing the corresponding correction model to apply residual correction of the measurement results, and then reduce the impact of conversion parameter error. Experiments show that, the proposed coordinate conversion method is simple and easy to realize, and improved the measurement accuracy of point cloud.(3)Conducting experimental study on elevation accuracy of the 3D laser scanning data. After filtering the collected data and introducing the commonly used mapping software, it is interpolated by using grid method, and compared the relationship between the elevation accuracy of different position and the variety of scanning range, and get the best position of target registration by considering density and height accuracy of the scan data.In summary, this paper’s experimental results of 3D laser scanner applied to digital terrain modeling put forward residual correction model of coordinate transformation. It has reference value to improve the precision of 3D scanning point cloud data and promote its engineering application.