Topographic Survey with Analytical Close Range Photogrammetry


Topographic survey uses to determine the relative locations of points (coordinates) on the earth's surface by measuring horizontal distances, differences in elevations and directions. Generally speaking the production of large scale topographic maps requires precise topographic survey with land surveying instrument such as (Total Station) which is costly and time consumed. The objective of this research is to produce topographic maps using an unconventional means through application analytical close range photogrammetry. The analytical close range photogrammetric method is characterized by low efforts and cost, the speed of topographic survey works, as well as the possibility of measuring and / or assessing places inaccessible. Photos strip was selected at University of Technology as a case study with area (400 m2). The fieldwork started with generation of ground control points around the area. A theodolite (wild T2) was used to measure the ground (X, Y, and Z) coordinates for GCPs within the study area. The strip consists of eight overlapped images, overlap more than 60% were captured using a single non metric digital camera (Canon EOS D500) (with a resolution of 15.10 mega pixels). After capturing images for study area two steps were used for processing data.The first step was used to process these images for producing 3D coordinates from 2D images with different methods by using two software. The first software using Matlab2014b dealing with different methods Sequential (R-I) and bundle adjustment (BA) methods, and another software ERDAS IMAGINE (LPS) using block bundle adjustment. The second step was used GIS software to producing large scale topographical map.The computed Root Mean Square Error (RMSE) for three methods (Resection – Intersection, Bundle Adjustment and Bundle Adjustment Block) and it was found that the RMSE in R-I method is (2.917cm) , RMSE in B-A method is (2.882cm) and RMSE in Bundle Block Adjustment method is (3.112cm). The final result was a topographic map with scale (1:100 and 1:200).