Feasibility study of VBS-RTK GPS supportedaerial triangulation for UAV images using control entities as control points

Abstract

Recently, UAV (Unmanned Aerial Vehicle) can be used in civil purpose such as mapping and disaster monitoring. UAV can collect high resolution images and fly under the cloud for mapping demands. VBS-RTK GPS (Virtual Base Station-Real Time Kinematic GPS) technique can be used to support bundle adjustment aerial triangulation of UAV images to reduce the demands of GCPs (ground control points). The offset between camera projection center and GPS antenna is solved by introducing drift parameter for each strip. Additionally, self-calibration bundle block adjustment can be employed in aerial triangulation to overcome imperfect calibration of non-metric camera. However, GCPs are still necessary to perform VBS-RTK GPS supported aerial triangulation for precise position and orientation of UAV images. In Taiwan, there are lots of historic aerial photogrammetric projects for large scale topographic mapping. If GCPs, called as control entities in this study, can be obtained from these projects, it can reduce the costs for surveying GCPs and improve the efficiency of aerial triangulation for UAV images. Therefore, this study will investigate the feasibility of GPS supported self-calibration bundle adjustment for UAV images by using control entities from historic aerial images as GCPs. Meanwhile, the appropriate configuration of control entities for VBS-RTK GPS supported self-calibration bundle adjustment for UAV images will be proposed in this study.