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Vibration Design of a Rigid Body Supported by Orthogonal Springs

직교스프링들에 의해 지지되는 강체의 진동 설계

  • 장선준 (연세대학교 대학원 기계공학과) ;
  • 이준호 (연세대학교 대학원 기계공학과) ;
  • 최용제 (연세대학교 기계공학부)
  • Published : 2007.01.01

Abstract

Vibration analysis of a rigid body supported by in-parallel linear springs can be greatly simplified by utilizing the conditions for a plane of symmetry. The vibration modes of an oscillatory system having plane of symmetry are classified into the in-plane and out-of-plane modes. From the viewpoint of screw theory, they represent respectively the vibration axes perpendicular to the plane of symmetry and lying in the plane of symmetry. In this paper, the sets of orthogonal and mutually intersecting three springs are used as resilient support of a rigid body. The geometrical conditions for the system to have a plane of symmetry and diagonalized stiffness matrix are presented. From the orthogonality of the vibration modes with respect to the inertia matrix, the geometrical relation between the reaction wrenches and the vibration modes are derived. This geometrical relation is then used to get the cubic design equation for the design of out-of-plane modes. The numerical design example of engine mounts is presented in order to explain the suggested design technique.

Keywords

Vibration Modes;Plane of Symmetry;Screw Theory;Orthogonal Springs;Engine Mount

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