Journal of Mechanical Science and Technology

  • 제16권6호
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  • Pages.799-809
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  • 2002
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  • 1738-494X(pISSN)
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  • 1976-3824(eISSN)
대한기계학회 (The Korean Society of Mechanical Engineers)
권호 표지

Error Analysis of a Parallel Mechanism Considering Link Stiffness and Joint Clearances

  • Park, Woo-Chun (Department of Mechanical Engineering, Korea University) ;
  • Song, Jae-Bok (Department of Mechanical Engineering, Korea University) ;
  • Daehie Hong (Department of Mechanical Engineering, Korea University) ;
  • Shim, Jae-Kyung (Department of Mechanical Engineering, Korea University) ;
  • Lim, Seung-Reung (Graduate Students, Department of Mechanical Engineering, Korea University) ;
  • Kyungwoo Kang (Graduate Students, Department of Mechanical Engineering, Korea University) ;
  • Park, Sungchul (Graduate Students, Department of Mechanical Engineering, Korea University)
  • 발행 : 2002.05.01
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초록

In order to utilize a parallel mechanism as a machine tool component, it is important to estimate the errors of its end-effector due to the uncertainties in parts. This study proposes an error analysis for a new parallel device, a cubic parallel mechanism. For the parallel device, we consider two kinds of errors. One is a static error due to link stiffness and the other is a dynamic error due to clearances in the parts. In this study, we propose a stiffness model for the cubic parallel mechanism under the assumption that the link stiffness is a linear function of the link length. Also, from the fact that the errors of u-joints and spherical joints are changed with the direction of force acting on the link, they are regarded as a part of link errors, and then the error model is derived using forward kinematics. Lastly, both the error models are integrated into the total error, which is analyzed with a test example that the platform moves along a circular path. This analysis can be used in predicting the accuracy of other parallel devices.

키워드

참고문헌

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