Performance Prediction of Landing Gear Considering Uncertain Operating Parameters

운용 파라미터의 불확실성을 고려한 착륙장치 완충성능 해석

  • Received : 2012.12.28
  • Accepted : 2013.04.03
  • Published : 2013.07.01


The performance estimation of a landing gear with uncertain parameters is presented. In actual use, many parameters can have certain degrees of variations that affect the energy absorbing performance. For example, the shock strut gas pressure, oil volume, tire pressure, and temperature can deviate from their nominal values. The objective function in this study is the ground reaction during touchdown, which is a function of the abovementioned parameters and time. To consider the uncertain properties, convex modeling and interval analysis are used to calculatethe objective function. The numerical results show that the ground reaction characteristics are quite different from those of the deterministic method. The peak load, which affects the efficiency and structural integrity, is increases considerably when the uncertainties are considered. Therefore, it is important to consider the uncertainties, and the proposed methodology can serve as an efficient method to estimate the effect of such uncertainties.


Landing Gear;Oleo-Pneumatic Shock Absorber;Uncertainty;Convex Modeling;Interval Analysis


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