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Theoretical Analyses on Actuator Stiffness and Structural Stiffness of Non-redundant and Redundant Symmetric 5R Parallel Mechanisms

비과구동, 과구동 대칭형 5R 병렬기구의 구동 및 구조 강성의 이론적 해석

  • Jin, Sang-Rok (School of Mechanical and Aerospace Engineering, Seoul National Univ.) ;
  • Kim, Jong-Won (School of Mechanical and Aerospace Engineering, Seoul National Univ.) ;
  • Seo, Tae-Won (School of Mechanical Engineering, Yeungnam Univ.)
  • 진상록 (서울대학교 기계항공공학부) ;
  • 김종원 (서울대학교 기계항공공학부) ;
  • 서태원 (영남대학교 기계공학부)
  • Received : 2011.09.28
  • Accepted : 2012.02.21
  • Published : 2012.09.01

Abstract

Redundant actuated parallel kinematic machines (PKMs) have been widely researched to increase stiffness of PKMs. This paper presents theoretical analyses on the stiffness of non-redundant and redundant actuated PKM. Stiffness of each mechanism is defined by summation of actuator and structural stiffness; the actuator stiffness is determined from displacements of actuators, and the structural stiffness is determined from deformations of links by external forces. Calculated actuator and structural stiffness of non-redundant PKM show same distribution in entire workspace. On the contrary, the actuator and the structural stiffness of a redundant PKM has very different distribution in the workspace; so, we conclude the structural stiffness of redundant PKM should be considered to design the redundant PKM. The results can be used to design and analyze non-redundant and redundant PKMs.

Acknowledgement

Supported by : 한국연구재단

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