A Comparative Analysis of UAV-RTK and UAV-PPK Methods in Mapping Different Surface Types

Authors : Remzi EKER, Ece ALKAN, Abdurrahim AYDIN

Pages : 12-25

Doi:10.33904/ejfe.938067

View : 17 | Download : 6

Publication Date : 2021-06-30

Article Type : Research Paper

Abstract :This study aimed to compare unmanned aerial vehicle insert ignore into journalissuearticles values(UAV); based real-time kinematic insert ignore into journalissuearticles values(RTK); and post-processing kinematic insert ignore into journalissuearticles values(PPK); methods via five approaches: an RTK-CORS method insert ignore into journalissuearticles values(M1);, a short-baseline PPK method obtaining corrections from a GNSS base station insert ignore into journalissuearticles values(M2);, and three long-baseline PPK methods that obtained corrections from the three Turkish RTK-CORS network TUSAGA-Aktif reference stations insert ignore into journalissuearticles values(M3: IZMI, M4: CESM, and M5: KIKA);. The comparison was based on the accuracy of the corrected camera positions, the average error of the camera locations computed in the photo-alignment and optimization process, georeferencing errors of the models via nine GCPs based on four scenarios, and Root Mean Square insert ignore into journalissuearticles values(RMS); errors in the Z-direction for different surface types insert ignore into journalissuearticles values(i.e. roads, shadows, shrubs, boulders, trees, and ground);. For the surface types of “ground”, “roads”, and “shrubs”, RMS error rates were obtained 10 cm lower than that of other surface types in all methods except M4. The greatest differences were obtained over trees and shadowed areas. The conclusion of these comparisons was that the lowest RMS error rate was determined on a solid textured surface. The consideration of mean RMS error regardless of surface type in such model comparisons is misleading.
Keywords : Accuracy comparison, GNSS, Photogrammetry, RTK PPK, Surface Types, UAV