| Title |
Enhanced Crack Width Measurement Using GPS Coordinates From Drone Filming |
| Authors |
김태우(Kim, Tae-Woo) ; 설동현(Seol, Dong-Hyeon) ; 김구연(Kim, Gu-Yeon) ; 김홍진(Kim, Hong-Jin) |
| DOI |
https://doi.org/10.5659/JAIK.2023.39.11.243 |
| Keywords |
Crack Width; Drone; Photogrammetry; Collinear Condition Equation; Sub Pixel |
| Abstract |
In this study, concrete crack widths were quantified by converting boundary sub-pixels, which were calculated using the Gradient Variation
Vector, into 3D ground coordinates following photogrammetry principles. A series of experiments was conducted to validate the proposed
method. Initially, twelve virtual cracks of different widths were affixed to a wall, and image-based measurements were conducted.
Additionally, field tests entailed capturing images of real cracks on structural surfaces and measuring crack widths at four specified distances
for precision assessment. The results revealed distinct patterns. In the virtual crack experiment, a noticeable trend emerged: as crack width
decreased and imaging distance increased, measurement errors tended to increase. Conversely, in the actual crack experiment, a consistent
trend in measurement accuracy was absent when compared to the virtual crack scenarios. Deviations remained generally minimal, and despite
variations, measurement errors stayed largely consistent |