드론 장착 카메라를 이용한 하천의 표면유속측정 = Measurement of Surface Velocity in Open Channels Using Cameras on a Drone

국문 초록 (Abstract)

본 연구의 목적은 드론에 장착된 카메라로 하천 수표면을 촬영하여 하천의 표면유속을 측정하는 방법을 개발하는 것이다. 표면영상유속계를 이용할 때, 폭이 넓은 하천의 경우 하천 양안이나 교량 등에서는 충분한 화각을 확보하기 어렵다. 드론을 이용하면 사람이 접근하기 힘든 지역도 쉽게 촬영이 가능하므로 원하는 하천 표면의 영상을 쉽게 촬영할 수 있다. 다만, 드론에 장착된 비디오 카메라는 야간에는 촬영이 어려우며, 아무리 정지비행을 잘 하더라도 영상에는 다소간의 흔들림이 항상 존재한다. 이를 해결하기 위해 본 연구에서는 열영상 카메라를 추가적으로 드론에 장착하고, 흔들린 영상에 대해서는 형태 정합법에 의해 보정을 하였다. 영상 보정 과정은 고정된 표정점을 영상에서 추적한 뒤, 기준 영상의 표정점과 보정 영상의 표정점이 일치하도록 보정하였다. 영상 보정 후 영상 처리와 분석프로그램을 통하여 유속을 도출한다. 실험 하천에 대해 적용한 결과 상당히 만족스런 결과를 얻었다.

다국어 초록 (Multilingual Abstract)

The present study aims to develop a drone-based surface image velocimeter to measure velocity fields of a river surface. When we measure water surface velocity using a surface image velocimeter, it is difficult to get a proper angle of view from bridges or river banks, especially for wide rivers. If we use a drone to take images of river surface, it is possible to access anywhere and get good angle of view. However, most video cameras installed by default on drones cannot take image in night time. And another problem is in most cases the images taken with a drone camera will have small and large sway due to drone stabilization. To solve the problems, we installed a far-infrared camera on a drone and corrected images using a pattern matching technique. In the image correction process, we tracked some reference points on images, and transformed the images to a reference image so that the locations of ground control points on transformed images match to those of the reference image. After the image correction, a surface image volocimeter software can calculates velocity fields from those images. The analyses showed fairly good results.

목차 (Table of Contents)

• Abstract
• 요지
• 1. 서론
• 2. 기존 연구에 대한 검토
• 3. 드론영상을 이용한 표면영상유속측정법
• 4. 결론 및 고찰
• References

참고문헌 (Reference)

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