Bundle adjustment of multi-station spherical panorama images with GPS positioning

In this study, we developed a newly designed portable panoramic image mapping system (PPIMS). It is specially designed for some areas that a vehicle-based mapping system is not allowed to enter. PPIMS can capture eight images simultaneously with e-GPS positioning. When images are taken from multiple stations, a large amount of images are needed to handle. Finding targets among images becomes a puzzled task. To resolve this difficulty, this study proposes a new concept of photogrammetry by using panoramic images. Eight images captured by PPIMS can form a spherical panorama image (SPI). Instead of using the original images, PPIMS SPIs are used for photogrammetric triangulation and mapping. Because the collinearity condition is not rigorously kept that causes a certain amount of error in multi-station network adjustment. We also propose a method to correct the imperfect geometry of PPIMS SPI. Two experiments were done. One is on the test field at Tzu-Chiang Campus, NCKU, Taiwan, and the other is at the Eternal Golden Castle. Both of them reveal bundle adjustment of SPI is feasible, and applying corrections for PPIMS SPIs is necessary and effective for bundle adjustment.