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http://dx.doi.org/10.20910/JASE.2018.12.4.64

Online Refocusing Algorithm Considering the Tilting Effect for a Small Satellite Camera  

Lee, Da Hyun (Defence Agency for Technology and Quality, Precedent Study Planning Team)
Hwang, Jai Hyuk (Dept. of Aerospace and Mechanical Engineering, Korea Aerospace University)
Hong, Dae Gi (Dept. of Aerospace and Mechanical Engineering, Korea Aerospace University)
Publication Information
Journal of Aerospace System Engineering / v.12, no.4, 2018 , pp. 64-74 More about this Journal
Abstract
Small high-resolution Earth observation satellites require precise optical alignment at the submicron level. However, misalignments can occur due to the influence of external factors during the launch and operation despite the sufficient alignment processes that take place before the launch. Thus, satellites need to realign their optical elements in orbit in what is known as a refocusing process to compensate for any misalignments. Refocusing algorithms developed for satellites have only considered de-space, which is the most sensitive factor with respect to image quality. However, the existing algorithms can cause correction error when inner and external forces generate tilt amount in an optical system. The present work suggests an improved online refocusing algorithm by considering the tilting effect for application in the case of a de-spaced and tilted optical system. In addition, the algorithm is considered to be efficient in terms of time and cost because it is designed to be used as an online method that does not require ground communication.
Keywords
Refocusing; Autofocusing; Self-focusing; Small Satellite Camera; MTF assessment;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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1 B. C. Braam, H. A. Van Mierlo, G. Buvril, and S. Gill, "Meteosat Second Generation refocusing mechanism," in Proceedings of 7th European Space Mechanisms and Tribology Symposium, B. H. Kaldeich-Schurmann 410, p. 27, 1997.
2 J. Foust, "Emerging opportunities for low-cost small satellites in civil and commercial space," 24th Annual AIAA/USU Conference on Small Satellites, 2010.
3 S. Lee and J. Song, "High resolution science observation satellite development trend," Science & Technology Policy 106, pp. 77-87, 1998.
4 Y. Jang, M. Park, S. Yu, S. Park, and G. Choe, "The trend and prospect of small satellite formation flying technology," Journal of The Korean Society for Aeronautical & Space Sciences Vol. 31, No. 7, pp. 136-149, 2003.   DOI
5 M. W. Werner, T. L. Roellig, F. J. Low, G. H. Rieke, M. Rieke, W. F. Hoffmann, E. Young, J. R. Houck, B. Brandl, G. G. Fazio, J. L. Hora, R. D. Gehrz, G. Helou, B. T. Soifer, J. Stauffer, J. Keene, P. Eisenhardt, D. Gallagher, T. N. Gautier, W. Irace, C. R. Lawrence, L. Simmons, J. E. Van Cleve, M. Jura, E. L. Wright, and D. P. Cruikshank, "The Spitzer space telescope mission," The Astrophysical Journal Supplement Series Vol. 154, No. 1, pp. 1-9, 2004.   DOI
6 M. Lee, J. Kim, J. Chang, and M. Kang, "Development of in-orbit refocusing mechanism for SpaceEye-1 electro-optical payload," Proceedings of SPIE 9972, 9972-10, 2016.
7 J. Jang, J. Kim, S. Yang, M. Kang, and E. Kim, 'Development of thermal control system for high resolution earth observation camera," Proceedings of The Spring Conference of Korean Society for Aeronautical & Space Sciences, No. 4, pp. 889-893, 2014.
8 D. Lee, Y. Youk, J. Yeon, S. Jang, and E. Lee, "Refocus mechanism development for high resolution electro-optical camera," Proceedings of The Autumn Conference of Korean Society Korean Society for Aeronautical & Space Sciences, No. 11, pp. 553-555, 2014.
9 D. Kim, Y. Choi, M. Kang, E. Kim, and H. Yang, "Optical alignment of a high-resolution optical earth observation camera for small satellites," Korean Journal of Optics and Photonics Vol. 15, No. 4, pp. 391-396, 2004.   DOI
10 J. Jo, J. Hwang, and J. Bae, "Online refocusing algorithm for a satellite camera using stellar sources," Optics Express Vol. 24, No. 5, pp. 5411-5422, 2016.   DOI
11 R. D. Gehrz, E. A. Romana, W. F. Hoffmann, J. P. Schwenker, J. E. Mentzell, J. L. Hora, P. R. Eisenhardt, B. R. Brandl, L. Armus, K. R. Stapelfeldt, D. C. Hines, A. K. Mainzer, E. T. Young, and D. G. Elliott, "The state of the focus and image quality of the Spitzer Space Telescope as measured in orbit," Proceedings of SPIE 5487, pp. 166-176, 2004.
12 H. G. J. Rutten and M. A. M. van Venrooij, "Telescope Optics: A Comprehensive Manual for Amateur Astronomers," Willmann-Bell, 1999.
13 A. Meygret, and D. Leger, "In-flight refocusing of the SPOT-1 HRV cameras," Proceedings of SPIE 2758, pp. 209-307, 1966.
14 D. Leger, F. Viallefont, E. Hillairet, and A. Meygret, "In-flight refocusing and MTF assessment of SPOT5 HRG and HRS cameras," Proceedings of SPIE 2758, pp. 224-231, 2003.
15 V. Amberg, L. Bernard, and C. Latry, "Star-based defocus computing technique for PLEIADES-HR satellites," Proceedings of SPIE 9643, 9643-03, 2015.