• Journal of the Institute of Electronics Engineers of Korea SC
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• v.46 no.3
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• pp.59-65
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• 2009

Recently, UAV(unmanned aerial vehicle) has evolved into various figure and become miniaturized. On using existing design method, it is hard to make modelling and standardizing design of flight control system of the figure including cylinder like pipe. These problems are caused by uncorrect express of nonlinearity in controller design. Therefore, it is developed through step of correct modelling and simulation on real time sing high efficiency computer in aircraft development of various figure. This is reducing period and expense of aircraft development. For the shake of solving these problems, in-design method has been devised by H.M. Wang. In this paper, an object of control is cylindrical UAV instead of the general figure of aircraft. It was analyzed flight condition, specification about level flight of the UAV and was presented algorithm to find control value.

• International Journal of Aeronautical and Space Sciences
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• v.15 no.3
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• pp.335-343
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• 2014

An airbag is an important safety system and is well known as a safety system in cars during an accident. Airbag systems are also used as a shock absorber for UAVs to assist with rapid parachute landings. In this paper, the dynamics and gas dynamics of five airbag shapes, cylindrical, semi-cylindrical, cubic, and two truncated pyramids, were modelled and simulated under conditions of impact acceleration lower than $4m/s^2$ to avoid damage to the UAV. First, the responses of the present modelling were compared and validated against airbag test results under the same conditions. Second, for each airbag shape under the same conditions, the responses in terms of pressure, acceleration, and emerging velocity were investigated. Third, the performance of a pressure relief valve is compared with a fixed-area orifice implemented in the air bag. For each airbag shape under the same conditions, the optimum area of the fixed orifice was determined. By examining the response of pressure and acceleration of the airbag, the optimum shape of the airbag and the venting system is suggested.