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Prediction and Verification of Water-entry Traces Size of Small Falling Objects into the Sea
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 Title & Authors
Prediction and Verification of Water-entry Traces Size of Small Falling Objects into the Sea
Min, Anki; Hwang, Tae-Won;
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An unmanned aerial photography method by using an unmanned helicopter is useful method for measuring of the water-entry traces of small falling objects into the sea. Pixel sizes on the aerial photograph may be too large due to a limit of camcorder resolution and a wide shooting area. If the pixel size is too large, identification of water-entry trace is impossible. Thus an accurate prediction of water-entry trace size is required. The traces of water-entry could be classified into three types such as splash, water column, and bubble. Diameters of each trace are predicted by water-entry impact pressure theories, cavity theories, and trial test results. The results are verified by drop tests using an unmanned helicopter at two water-entry speeds. As a result, prediction and test results showed sufficient similarity to evaluate the identifiability of water-entry trace.
Traces of Water-entry;Unmanned Aerial Photography;Small Falling Object;
 Cited by
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