Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Dynamic Analysis of Gimbal Structure System Including Nonlinear Elastic Rubber Vibration Isolator with Shock Acceleration

비선형 탄성 방진 고무부에 충격 가속도를 받는 짐발 구조 시스템의 동적 해석

  • Lee, Sang Eun (Seeker & E/O IR R&D Lab., LIG Nex1 Co., Ltd.) ;
  • Lee, Tae Won (Dept. of Mechanical Design Engineering, Kumoh Nat'l Institute of Technology)
  • 이상은 (LIG 넥스원 연구개발본부 탐색기&광학연구센터) ;
  • 이태원 (금오공과대학교 기계설계공학과)
  • Received : 2015.10.28
  • Accepted : 2016.01.26
  • Published : 2016.04.01
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Abstract

When shock acceleration is applied to a mechanical system, it may cause malfunctioning and damage to the system. Hence, to prevent these problems when developing a gimbal structure system for observation reconnaissance, the MIL-STD-810G shock standard must be satisfied as a design specification. Rubber vibration isolators are generally assembled on the base of the system in order to reduce the shock transferred from the aircraft. It is difficult to analyze the transient behavior of the system accurately, because rubber has a nonlinear load-deformation curve. To treat the nonlinear characteristic of the rubber, bilinear approximation was introduced. Using this assumption, transient responses of the system under base shock acceleration were calculated by the finite element method. In addition, experiments with a true prototype were performed using the same conditions as the analytical model. Compared with experimental data, the proposed numerical method is useful for the transient analysis of gimbal structure systems, including rubber vibration isolators with nonlinear stiffness and damping.

충격 가속도가 기계 시스템에 가해지면 시스템의 기능 저하 및 파손이 발생할 수 있다. 이러한 문제점을 방지하기 위하여 감시 정찰 비행기에 장착되는 짐발 구조 시스템은 설계 사양으로 MIL-STD-810G 충격 규격을 반드시 만족해야 한다. 일반적으로 비행기에서 전달되는 충격을 완화하기 위하여 시스템의 기초부에 방진고무가 설치된다. 고무는 비선형 하중-변형 관계를 가지므로 정확한 시스템의 충격 응답 계산이 어렵다. 이를 해결하기 위하여 비선형 특성을 2개의 선형으로 근사화하여 기초부에 충격 가속도를 받는 시스템의 동적 해를 유한요소법으로 구하였다. 그리고 동일한 조건에서 행한 실험과 비교 결과 제안된 해석 방법이 강성과 감쇠에서 비선형성을 갖는 방진고무가 포함된 짐발 구조 시스템의 동적 해석에도 유용함을 입증하였다.

Keywords

References

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