Bundle Adjustment of Multi-station Spherical Panorama Images with GPS Positioning

Abstract

In this study we developed a portable panoramic image mapping system (PPIMS) It is designed for some areas that vehicle-based mapping systems are not allowed to enter such as rugged terrains forest areas and etc PPIMS is a specially designed platform equipped with eight cameras and a GPS receiver that it 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 and measure Finding targets among images becomes a puzzled task This study proposes a new concept of photogrammetry by using panoramic images It not only breaks the limitation of FOV in traditional photogrammetry but also resolves the problem that handling a lot of images are confusing Eight images captured with PPIMS can form an spherical panorama image (SPI) which is called PPIMS SPI The PPIMS SPIs are then used for photogrammetric triangulation and mapping instead of using the original images Because the collinearity condition is not rigorously kept that causes the gaps on the cutting edges of overlapped images This study first proposes using SPIs in bundle adjustment to solve the orientation of stations and coordinates of conjugate points in the object space Then we aim at the deficiency of PPIMS SPI to fix the imperfect geometry of PPIMS SPIs by coordinates of object points solved And solve the orientation of stations and coordinates of conjugate points in the object space again until the convergence Two experiments using PPIMS SPIs for bundle adjustment are done and both their results are validated with check points One is on the test field in Tzu-Chiang Campus and another one is in the Eternal Golden Castle (EGC) which has the much complicated landscape On the test field in Tzu-Chiang Campus the RMSD values in three directions decreases significantly from (±0 321m ±0 741m ±0386m) to (±0 209m ±0 376m ±0 270m) after applying corrections for PPIMS SPIs In EGC project the RMSD values in three directions become consistent and are about 0 1 m after applying corrections for PPIMS SPIs Both of them confirm bundle adjustment of SPI is possible and applying corrections for PPIMS SPIs is necessary and effective for bundle adjustment We also compare the results using SPIs with original images to understand their real differences On the test field in Tzu-Chiang Campus the maximum difference of rotation angles is about 0 03 degrees Ignoring two unreliable check points the maximum difference of check point coordinates is about 0 06 meters In EGC project the maximum difference of rotation angles is about 0 03 degrees and all difference of check point coordinates are under 0 04 meters The above confirms both results using SPIs are consistent with original images that presents SPIs can replace original images in bundle adjustment

Date of Award	2014 Aug 19
Original language	English
Supervisor	Yi-Hsing Tseng (Supervisor)