• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.383.1-383
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• 2002

This research is concerned with ground experiments for satellite solar array deployment. The dynamic characteristics of the strain energy hinge is very important since it affects the shape and the speed of the solar array deployment. the rapid deployment results in overshoot and undesirable residual vibrations. The experimental results are in good agreement with theoretical results.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.9
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• pp.82-87
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• 2003

This research is concerned with ground experiments for satellite solar array deployment as well as the validation of theoretical modeling technique presented in the previous paper. We carried out the experiments on the strain energy hinge with stopper to investigate he buckling characteristics of the SEH, which affects the shape and the speed of the solar array deployment. The moment-angle diagram obtained from the experiments was later combined with the theoretical deployment model. This paper also presents the details of the ground experiments performed at the Korea Aerospace Research Institute(KARI) . It was found that the ground experimental results were in good agreement with the theoretical predictions thus validating the dynamic modeling technique.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.842-847
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• 2002

This research is concerned with ground experiments for satellite solar array deployment. The dynamic characteristics of the strain energy hinge is very important since it affects the shape and the speed of the solar array deployment. The rapid deployment results in overshoot and undesirable residual vibrations. The experimental results are in good agreement with theoretical results.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.9
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• pp.38-45
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• 2003

This research is concerned with the dynamic modeling of the multi-purpose satellite with deployable solar arrays equipped with strain energy hinges(SEH). To this end, we proposed the use of the equivalent torsional spring for the SEH and derived the equations of motion assuming that the satellite and solar arrays are being rigid. We also considered the effect of the support string for the ground experiment model, which has been observed as a critical factor affecting the deployment in the ground experiments. From the numerical simulation results, it is found that solar arrays are deployed in a similar pattern but the hub motions are different because of the support strings. It was concluded that the non-gravity deployment of the solar arrays can be approximately simulated by the ground experimental facility. The effects of the support string are also investigated by varying the length of the string. It was found that the current length of the string is adequate for the ground experiment. Ground experimental results will follow.

• Geophysics and Geophysical Exploration
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• v.8 no.1
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• pp.59-66
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• 2005

The main purpose of this paper is to describe a highly efficient common mid-point (CMP) data acquisition method for ground-penetrating radar (GPR) surveying, which is intended to widen the application of GPR. The most important innovation to increase the efficiency of CMP data acquisition is continuous monitoring of the GPR antenna positions, using a real-time kinematic Global Positioning System (RTK-GPS). Survey time efficiency is improved because the automatic antenna locating system that we propose frees us from the most time-consuming process-deployment of the antenna at specified positions. Numerical experiments predicted that the data density and the CMP fold would be increased by the increased efficiency of data acquisition, which results in improved signal-to-noise ratios in the resulting data. A field experiment confirmed this hypothesis. The proposed method makes GPR surveys using CMP method more practical and popular. Furthermore, the method has the potential to supply detailed groundwater information. This is because we can convert the spatially dense dielectric constant distribution, obtained by using the CMP method we describe, into a dense physical value distribution that is closely related to such groundwater properties as water saturation.