Measurement Method Research And Systems Development Of Vehicle Lidar In Farmland Three-dimensional Terrain

The land leveling has great significance to improve the utilization ratio of irrigation waterand to increase the production and quality of crops, as well to establish a foundation forrealizing the agricultural production processes of precision sowing, precision fertilizing andprecision reaping. For realizing the assessment of farmland leveling effect, and to provide datasupport for farmland leveling, it needs to measure the terrain of farmland’s surface. But thetraditional measuring methods are hard to reflect the real situation of farmland’s surface asthey requires too much time and energy, as well have lower density in measuring points.With the rapid development of techniques in electronics, optics and computer in recentyears, the laser radar technology has become a popular measuring technique. It has greatsignificance to utilize the Laser radar technology in measurement of land leveling, which cansubstantially increase the speed of the measurementand improve the effeciency of landleveling. Therefore, this paper is foucing on how to access the high-density point cloud datarapidly and accuratly, and then to generate the farmland terrain model.The paper analyze the current status and main fields of application of laser radarmeasurement techniques in home and abroad. The existing theories applied to farmlandterrain measurement process can not meet the need to obtain fast and accurate measurementdata in the land arrangement. On the basis of existing research, to develop data collectionsoftware, and to calibrate the system.To study the data preprocessing method of vehicle lidar,including the standard format of LAS and the coordinate system conversion algorithm fusedby the data of laser radar. And to focus on the study of point cloud filtering method forfarmland terrain and the filter experiment. Described the error sources of vehicle lidarplatform farmland terrain measurement, and to evaluate the measuring accuracy of thevehicle lidar platform by using the method of relative analysis to compare it with the DEM,which is measured by the vehicle lidar platform and RTK.To design and develop the dataprocessing software to measure farmland three-dimensional terrain by using vehicular laserscanner, it will obtain functions of measuring data fusion, point cloud data input and output,point cloud data wave filtering, three-dimensional display of point cloud data, establishmentof a TIN model and display of three-dimensional model and so on. Through the study of the measuring method of vehicular laser scanner in farmland three-dimensional terrain, it will establish a complete process from data acquisition to three-dimensional terrain model generation, as well to anaylze its accuracy. The study will havepractical and reference significances in application of the vehicle lidar technology in landleveling.