The study on the feasibility of Land Resurvey with UAV photogrammetry

• Main Authors: Chiang, Cheng-Chu, 江政矩
• Other Authors: Chio, Shih-Hong
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/9n6wpn

碩士 === 國立政治大學 === 地政學系 === 107 === Survey of boundary verification affects people's well-being. According to the methods of surveying and the ways of preservation, there are three kind of maps, i.e. digital cadastral maps, graphic cadastral maps and digitalized graphic cadastral maps. The coordinate system of the digital cadastral maps have been unified into TWD97 cadastral coordinate system, so the surveyors can use digital method to perform boundary verification. Additionally, though graphic cadastral maps have been digitalized for the past few years, digitalized graphic cadastral maps still preserve differential shrinkage, wrinkles, folds and damage of the original maps. It will cause problems such as the difference between maps and the map of land detail situation, map join of the map sheets, and the change of the area after map registering. Therefore, map registration with land detail situation should be done before boundary verification. For most studies on the boundary verification of the digital graphic cadastral maps used ground survey to survey land detail situation to perform map registration. Compared to ground survey, UAV photogrammetry can provide lots of land detail situation. Moreover, the current map registration only locally focuses on the neighborhoods of the parcel for boundary verification. UAV photogrammetry can measure land detail situation globally to perform map registration in the whole area. Therefore, it can reduce the problem of local consistence from local land detail situations surveying by ground surveying and increase the reliability of the map registration globally. Additionally, for the boundary verification in digital cadastral areas or digitalized graphic areas, control points are probably lost. Using space intersection of aerial photogrammetry by multiple bundles to measure the coordinates of control points can bring more flexibility when using free station method for verification of parcel points. Therefore, this study used four-rotor UAV carried middle format metric camera with 55 mm focal length at flying height about 300 meters to collect the images with 80% endlap and sidelap and 3cm ground sampling distance. Before that, the suitable control points were targeted and surveyed by eGNSS. After that, Pix4dMapper and ORIMA software were employed to perform aerotriangulation, the result show that the control points for verification of parcel points can be measured in Pix4Dmapper by space intersection of aerial photogrammetry by multiple bundles or using the aerotriangulation result of ORIMA to generate undistorted images and import these images with related results into Pix4Dmapper for determining the coordinates of control points by space intersection of aerial photogrammetry by multiple bundles are possible. Moreover, the generated orthophoto can identify the land detail situation and the land detailed map of generated by UAV aerial photogrammetry can assist map registration using Affine transformation in ArcMap can make the cadastral map and land detail situation more consistent. The difference between land detail points to cadastral lines can be reduced by 2-9 centimeters after map registration. Finally, the parcel points can be stakeout to complete the process of boundary verification, and the result proves that UAV photogrammetry is of the feasibility to assist the boundary verification.