Parametric Study on the tendency of Stiffness Variation using Variable Stiffness Mechanism

변수변화에 따른 가변강성 메커니즘의 강성변화 경향성에 관한 연구

  • Ham, KiBeom (School of Mechanical Engineering, SunMoon University) ;
  • Han, Jiho (Department of Electronic Engineering, SunMoon University) ;
  • Jeon, JongKyun (School of Mechanical Engineering, SunMoon University) ;
  • Park, YongJai (School of Mechanical Engineering, SunMoon University)
  • 함기범 (선문대학교 기계공학과) ;
  • 한지호 (선문대학교 전자공학과) ;
  • 전종균 (선문대학교 기계공학과) ;
  • 박용재 (선문대학교 기계공학과)
  • Received : 2016.03.15
  • Accepted : 2016.06.02
  • Published : 2016.06.30


In general, a system can be stable when it is designed with a rigid material. However, the use of a rigid system can be limited, such as grasping a glass or using a small surgical instrument. To resolve this limitation, a variable stiffness mechanism was developed using a flexible material. Previous research verified the variable stiffness mechanism where flexible segments and rigid segments were connected alternately in series. However, research into the design parameters of the variable stiffness structure is needed to satisfy the desired stiffness. Therefore, a variable stiffness structure was tested by varying the design parameters to confirm the trend of the stiffness variation. When the radius of the structure becomes larger, the stiffness increases. The stiffness increased with decreasing length of the flexible segments. Under the same design parameters, the length of the flexible segments had a greater effect on the stiffness than the length of the rigid segments. In addition, the stiffness was estimated using the pseudo rigid body model and was compared with the experimental results. This parametric study can be used as a design guideline for designing the variable stiffness mechanism to satisfy the desired stiffness.


Supported by : 한국연구재단


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