1- university
Abstract: (157 Views)
Extended Abstract
Introduction and Objective: One of the products of photogrammetry and remote sensing is the digital model of the earth's surface, which is the basis of many widely used projects. Photogrammetry provides the user with the ability to create an accurate 3D model using 2D images. This research aims to investigate the height accuracy of the digital model of the land surface obtained from UAV images using accurate ground control points with different numbers and distribution and without ground control points to extract the accurate digital model of the ground surface with high and medium quality processing methods in the forests of District 1of Darabkola, Sari.
Materials and Methods: UAV images in suitable weather conditions with a flight height of100 meters above the ground, overlapping length of 85% and width of 75%, and with a speed of 5 meters per second by Phantom 3 Pro quadcopter drone in Bahman 1401 in a part of Darabkla forests with a length of about 2 kilometers 200 meters wide road around the road and in three separate flight projects were received during different days, the position of the points of ground reality observations was done using differential DGPS. Several ground control points were made for accurate ground referencing of the images and preparation of a precise and integrated orthophoto mosaic of the harvested area using differential DGPS. Digital elevation models of the area prepared with ground control points and without control points were processed and compared using Agiosoft Photoscan
Results: The results showed that the average point error (ME) for the digital height model prepared with high-quality control points was1.01 m and for the medium quality method was 1.21 m , while for the digital height model prepared without high-quality control points, It was 11.05 meters high and 10.72 meters with average quality. Also, the root mean square absolute error (RMSE) of the height values for the height digital model prepared with control points with high-quality method was 2.33 meters , and with medium quality was 2.39 meters . For the digital model, the height prepared without control points was 13.67 meters with high quality and 13.42 meters with medium quality. The root means square relative error (RMSE%) for the height digital model prepared with high-quality control points was 0.87% and with medium quality 0.90%, while for the height digital model prepared without high-quality control points 5.14% and average quality was 5.04%. In addition, the results of the paired T-test at the level of 5 and 1% probability of error showed that there was no significant difference between the height of the ground collection points and the digital height model with high and medium quality control points, but between the height of the ground collection points and the digital height model of the preparation without control points, there was a significant difference with high and medium quality methods.
Conclusion: The results of the research show that the use of accurate ground control points in the imaging and production of digital elevation models using UAV images produces accurate elevation digital models, and high-quality processing also increases elevation and even planar accuracy
Introduction and Objective: One of the products of photogrammetry and remote sensing is the digital model of the earth's surface, which is the basis of many widely used projects. Photogrammetry provides the user with the ability to create an accurate 3D model using 2D images. This research aims to investigate the height accuracy of the digital model of the land surface obtained from UAV images using accurate ground control points with different numbers and distribution and without ground control points to extract the accurate digital model of the ground surface with high and medium quality processing methods in the forests of District 1of Darabkola, Sari.
Materials and Methods: UAV images in suitable weather conditions with a flight height of
Results: The results showed that the average point error (ME) for the digital height model prepared with high-quality control points was
Conclusion: The results of the research show that the use of accurate ground control points in the imaging and production of digital elevation models using UAV images produces accurate elevation digital models, and high-quality processing also increases elevation and even planar accuracy
Send email to the article author
| Rights and permissions | |
 |
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. |