DOI QR코드

DOI QR Code

Accuracy Assessment of Feature Collection Method with Unmanned Aerial Vehicle Images Using Stereo Plotting Program StereoCAD

수치도화 프로그램 StereoCAD를 이용한 무인 항공영상의 묘사 정확도 평가

  • Received : 2019.11.20
  • Accepted : 2020.01.23
  • Published : 2020.04.01

Abstract

Vectorization is currently the main method in feature collection (extraction) during digital mapping using UAV-Photogrammetry. However, this method is time consuming and prone to gross elevation errors when extracted from a DSM (Digital Surface Model), because three-dimensional feature coordinates are vectorized separately: plane information from an orthophoto and height from a DSM. Consequently, the demand for stereo plotting method capable of acquiring three- dimensional spatial information simultaneously is increasing. However, this method requires an expensive equipment, a Digital Photogrammetry Workstation (DPW), and the technology itself is still incomplete. In this paper, we evaluated the accuracy of low-cost stereo plotting system, Menci's StereoCAD, by analyzing its three-dimensional spatial information acquisition. Images were taken with a FC 6310 camera mounted on a Phantom4 pro at a 90 m altitude with a Ground Sample Distance (GSD) of 3 cm. The accuracy analysis was performed by comparing differences in coordinates between the results from the ground survey and the stereo plotting at check points, and also at the corner points by layers. The results showed that the Root Mean Square Error (RMSE) at check points was 0.048 m for horizontal and 0.078 m for vertical coordinates, respectively, and for different layers, it ranged from 0.104 m to 0.127 m for horizontal and 0.086 m to 0.092 m for vertical coordinates, respectively. In conclusion, the results showed 1: 1,000 digital topographic map can be generated using a stereo plotting system with UAV images.

현재 무인항공사진측량을 이용한 지도제작의 지형·지물 묘사는 주로 벡터화로 이루어지고 있다. 그러나 벡터화는 평면과 표고 위치를 별도로 취득하기 때문에 시간이 많이 소요되고 수치표면모델에서 표고값을 추출 할 때 과대 오차가 발생될 수 있다. 이에 3차원 공간정보를 동시에 취득가능한 수치도화의 필요성이 증가하고 있으나, 고가의 도화장비가 필요하고 무인항공영상의 수치도화 기술이 불완전한 단점이 있다. 이에 본 연구에서는 저가의 시스템으로 수치도화가 가능한 Menci사의 StereoCAD를 이용하여 지형·지물의 묘사정확도를 분석 평가하였다. 무인항공영상의 취득은 Phantom4 pro에 FC 6310 카메라를 탑재하여 비행고도 90 m에서 GSD (Ground Sample Distance) 3 cm로 촬영하였다. 정확도 분석은 검사점과 점·선·면형 레이어별 모서리에 대한 지상측량결과와 도화결과의 3차원 좌표의 차이를 산출하여 비교하였다. 그 결과 검사점의 RMSE는 평면 0.048 m, 표고 0.078 m이고, 레이어별 RMSE는 평면이 0.104~0.127 m, 표고는 0.086~0.092 m로 나타나 무인항공영상의 입체도화로 1:1,000 수치지형도 제작의 가능성을 입증할 수 있었다.

Keywords

References

  1. Choi, Y. W., You, J. H. and Cho, G. S. (2015). "Accuracy analysis of UAV data processing using DPW." Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography, Vol. 23, No. 4, pp. 3-10 (in Korean).
  2. Jung, S. H., Lim, H. M. and Lee, J. K. (2010). "Acquisition of 3D spatial information using UAV photogrammetric method." Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography, Vol. 28, No. 1, pp. 161-168 (in Korean).
  3. Kim, D. I., Kang, D. W. and Lee, H. (2017). "Analysis of 3D-digital plotting using unmanned aircraft vehicle (UAV) stereo images." Proceedings of Korean Society for Geospatial Information Science, KSGIS, pp. 73-75 (in Korean).
  4. Kim, D. P. (2019). Accuracy analysis of feature collection methods using UAV-Photogrammetry, Master Thesis, Dong-A University, Busan, Korea (in Korean).
  5. Lee, J. O. and Lee, S. B. (2018). "Quality evaluation method for surveying result with UAVs." Proceedings of Korean Society for Geospatial Information Science, KSGIS, pp. 265-266 (in Korean).
  6. Lee, J. O. and Sung, S. M. (2016). "Evaluating spatial resolution for quality assurance of UAV images." Spatial Information Research, Vol. 24, No. 2, pp. 141-154. https://doi.org/10.1007/s41324-016-0015-0
  7. Lee, J. O., Sung, S. M. and Kim, D. P. (2019). "Accuracy assessment of stereo plotting with UAV images." Proceedings of Korean Society for Geospatial Information Science, KSGIS, pp. 142-143 (in Korean).
  8. Lim, H. M. (2010). Construction and updating of 3D spatial information for small areas using UAV, Ph.D. Dissertation, Chungbuk National University, Cheongju, Korea (in Korean).
  9. Lim, S. B., Seo, C. W. and Yun, H. C. (2015). "Digital map updates with UAV photogrammetric methods." Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography, Vol. 33, No. 5, pp. 397-405 (in Korean). https://doi.org/10.7848/ksgpc.2015.33.5.397
  10. Menci (2019). StereoCAD, Available at: https://www.mencisoftware.com/stereocad (Accessed: June 20, 2019).
  11. National Geographic Information Institute (NGII) (2018). Guidelines for the public survey using UAV, NGII Guidelines No. 2018-1075 (in Korean).
  12. Park, H. S. (2011). Precision assessment of stereo mapping using DMC images with different overlap ratios, Master Thesis, The University of Seoul, Seoul, Korea (in Korean).
  13. Rhee, S. and Kim, T. (2017). "Investigation of 1:1,000 scale map generation by stereo plotting using UAV images." The International Archives of the Photogrammetry, Remote Sensing, and Spatial Information Sciences, 2016 ISPRS International Conference on UAV in Geomatics, Bonn, Germany, Volume XLII-2/W6, pp. 319-324.
  14. Seo, S. I. and Lee, B. K. (2017). "In-situ self-calibration of non-metric camera and digital stereo plotting for public survey." Journal of the Korean Society of Surveying, Geodesy, Photogrammetry, Vol. 35, No. 3, pp. 145-154 (in Korean).
  15. Wolf, P. R. and Dewitt, B. A. (2000). Elements of photogrammetry with applications in GIS, McGraw-Hill, New York, NY.
  16. Yun, G. H., Kim, D. I., and Song, Y. S. (2018). "Accuracy assessment on the stereoscopic based digital mapping using unmanned aerial vehicle images." Journal of Cadastre & Land Information, Vol. 48, No. 1, pp. 111-121 (in Korean).