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http://dx.doi.org/10.20910/JASE.2018.12.4.75

A Motor-Driven Focusing Mechanism for Small Satellite  

Jung, Jinwon (Dept. of Aerospace and Mechanical Engineering, Korea Aerospace Univ.)
Choi, Junwoo (Dept. of Aerospace and Mechanical Engineering, Korea Aerospace Univ.)
Lee, Dongkyu (Dept. of Aerospace and Mechanical Engineering, Korea Aerospace Univ.)
Hwang, Jaehyuck (School. of Aerospace and Mechanical Engineering, Korea Aerospace Univ.)
Kim, Byungkyu (School. of Aerospace and Mechanical Engineering, Korea Aerospace Univ.)
Publication Information
Journal of Aerospace System Engineering / v.12, no.4, 2018 , pp. 75-80 More about this Journal
Abstract
The working principle of a satellite camera involves a focusing mechanism for controlling the focus of the optical system, which is essential for proper functioning. However, research on focusing mechanisms of satellite optical systems in Korea is in the beginning stage and developed technology is limited to a thermal control type. Therefore, in this paper, we propose a motor-driven focusing mechanism applicable to small satellite optical systems. The proposed mechanism is designed to generate z-axis displacement in the secondary mirror by a motor. In addition, three flexure hinges have been installed on the supporter for application of preload on the mechanism resulting in minimization of the alignment error arising due to manufacturing tolerance and assembly tolerance within the mechanism. After fabrication of the mechanism, the alignment errors (de-space, de-center, and tilt) were measured with LVDT sensors and laser displacement meters. Conclusively, the proposed focusing mechanism could achieve proper alignment degree, which can be applicable to small satellite optical system.
Keywords
Focusing mechanism; Schmidt-Cassegrain telescope; Small satellite; Flexure hinge; Optical system alignment;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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