VBS-RTK GPS Supported Positioning and Orientation for Helicopter UAS Thermal Images

• Main Authors: Hsu, Ling Yi, 許翎㳖
• Other Authors: 邱式鴻
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/2b8ddu

碩士 === 國立政治大學 === 地政研究所 === 102 === Thermal infrared images can show the temperature change of objects that represent the significant characteristics; therefore they have been applied on many fields. With the development of UAS (Unmanned Aircraft Systems), the thermal infrared camera can be carried on the Helicopter UAS to collect thermal images with high resolution in a local area more efficiently. However, the ground control marks for thermal images are uneasy to be set up. In this study, the Trimble BD970 GNSS OEM board will be carried on the Helicopter UAS to collect GPS data by VBS-RTK GPS technique to support the bundle adjustment for the positioning and orientation of collected thermal images, i.e. AT (Aerial Triangulation). In theorey, the GPS antenna offset is not changed and can be viewed as constant. Therefore, in this study, the new model based on bundle adjustment will be developed to solve GPS antenna offset, exterior orientation parameters and the object coordinate of tie points simultaneously by unified least squares adjustment. Besides, thermal infrared camera is a non-metric camera. In order to acquire high precision camera parameters for AT, thermal infrared camera will be calibrated by field method. In this study, the simulated tests verify the feasibility of the new developed model for GPS supported aerial triangulation and show that the GPS antenna offset can be solved based on the ideal accuracy of GPS observations and the observation constraint of GPS antenna offset. Due to the bad accuracy of GPS observations in real data collection, the GPS antenna offset can be not solved. Besides, tie point matching for thermal images is so hard, thus the connection among images is not strong. Therefore, only the accuracy of real test data consisted of many strips with two cross trips with double control points at each corner is the same as the accuracy of simulated data. Although the accuracy of GPS obervations is bad, the GPS observations can also be used to support the bundle adjustment for the positioning and orientation of thermal images under better block geometry and ground control points still can be reduced.