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“Stiffness Analysis and Optimization of a Co-axial Spherical Parallel Manipulator”

Authors: Guanglei Wu,
Affiliation: Aalborg University
Reference: 2014, Vol 35, No 1, pp. 21-30.

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Keywords: Spherical parallel manipulator, virtual spring, Cartesian stiffness matrix, singular value decomposition, stiffness optimization

Abstract: This paper investigates the stiffness characteristics of spherical parallel manipulators. By virtue of singular value decomposition, the 6x6 dimensionally inhomogeneous Cartesian stiffness matrix is transformed into two homogeneous ones, i.e., the rotational and translational stiffness matrices. The decomposed singular values and the corresponding vectors indicate the directions of high/weak stiffness and the stiffness isotropy for the manipulator at a given configuration. Two indices, one for rotation and the other for translation, are introduced to optimize the manipulator stiffness and to map the stiffness isocontours over the workspace to show an image of the overall stiffness.

PDF PDF (2616 Kb)        DOI: 10.4173/mic.2014.1.2

DOI forward links to this article:
  [1] Alessandro Cammarata, Ivo Caliņ, Domenico D Urso, Annalisa Greco, Michele Lacagnina and Gabriele Fichera (2016), doi:10.1016/j.jsv.2016.08.014
  [2] S. Ramana Babu, V. Ramachandra Raju and K. Ramji (2016), doi:10.1007/s12206-016-0847-5

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  title={{Stiffness Analysis and Optimization of a Co-axial Spherical Parallel Manipulator}},
  author={Wu, Guanglei},
  journal={Modeling, Identification and Control},
  publisher={Norwegian Society of Automatic Control}


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