• 한국생산제조학회지
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• 제23권1호
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• pp.21-26
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• 2014

An arrow produced by a manufacturing process is evaluated using the archer's paradox and the intensity of the impact point. The accuracy rate in particular is changed by the arrow's vibrational movement, which is called the archer's paradox. The archer's paradox occurs not only in the right, left, upward, and downward directions, but in all directions. The optimized value of the archer's paradox has not been studied yet. This paper proposes to measure the archer's paradox to determine its optimized value. Measuring the archer's paradox using a high-speed camera is expensive, and it is difficult to translate the result to a numerical value. However, the device for measuring the archer's paradox proposed in this paper is inexpensive, and the results are easy to convert to a numerical value. Therefore, this device is more suitable for optimization of the archer's paradox than a high-speed camera. In this paper, we propose to measure the size of the paradox using multiple frames, which can measure the position of an arrow moving at a speed of 300km/h to within millimeters. We calculate the size of the paradox experimentally using the measured location in each frame. This value is not an approximate value, but an accurate numerical value.

• 한국생산제조학회지
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• 제21권3호
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• pp.459-464
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• 2012

The point of impact, the shot group, and the flight traces depend on the combination of unique features which decide moving traces of the arrow (paradox of the archer, length of the arrow shaft, weight, angle of the feather, and spline of the arrow shaft). The more dense the impact points in the shot group and the earlier elimination of paradox of the archer, the higher assessment is given for the product. However, there is no way to objectively assess the efficiency and quality of the arrow, and there is no numeric data to be used as the basis for comparison with other products. Although capturing the images of flying arrow using a high-speed motion picture camera is possible, we are limited to observation from specific view angle only. Hence, the criteria for efficiency and quality assessment are mostly based on subjective opinions of experts or hunters, or review on consumers' remarks. In this paper, we propose a hardware composition that are based on three detection frames consisting of line lasers and photo diode arrays without the high-speed motion picture camera. Predicated on measured coordinates data, a nobel method for the archer's paradox measurement, a key parameter that determine the arrow's trajectory, and corresponding numerical analysis model is proposed.

• 한국지능시스템학회논문지
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• 제22권4호
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• pp.521-526
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• 2012

제조공정을 통해 생산된 화살의 성능은 화살의 이동궤적(궁사의 패러독스)과 탄착점의 집적도에 따라 좌우된다. 특히 동일한 환경에서 반복적으로 화살의 슈팅실험을 수행할 경우, 반복실험에서 얻어진 화살의 탄착점 집적도는 화살 성능 평가에서 중요한 객관적 지표가 된다. 그러나 화살의 탄착점에 대한 분석은 현재 상용화된 기술이 부족하며, 기존의 연구들은 화살의 성능에 영향을 미치는 제조공정 변수(화살깃, 화살촉, 화살의 곧기, 중량, 외경, 스파인)만을 최적화하려는 방향으로 기술력이 집중되어 있다. 본 논문에서는 화살의 주요성능지표인 화살의 탄착점 측정 자동화를 위해, Mamdani 퍼지 추론 시스템(Mamdani Fuzzy Inference System)과 도형의 닮음(Similarity of Polygon)을 이용한 화살의 탄착점 측정 시스템을 제안한다. 라인레이저(Line Laser)와 포토다이오드어레이(Photo Diode Array)를 이용하여 고속(약 275km/h)으로 이동하는 화살의 탄착점 데이터를 계측하고, 계측된 데이터를 퍼지 추론과 도형의 닮음을 이용하여 화살의 탄착점으로 사상(Mapping) 시킨다.