Stiffness Analysis for a Novel Parallel-Robot Based High-Precision Flexible Assembly Fixture


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In this paper, a novel parallel mechanism (3-RRRS/UPR) used in flexible fixture with configuration composed of two parallel robots (2-RR and 3-RRRS/ UPR) is presented. First, system modeling including the mobility study is conducted. Then a novel methodology is proposed that makes use of screw theory to analyze the deformation and stiffness of the mechanism: firstly we identified the existence of the deformation of the subchain, in terms of the relationship between the effective screw and deformation screw; then we took the deformation as an infinitesimal motion of the mechanism, and the stiffness matrix corresponding to the deformation can be deduced. Finally the global stiffness matrix of the whole mechanism is modeled by assembling different stiffness characters based on the presented methodology.



Key Engineering Materials (Volumes 364-366)

Edited by:

Guo Fan JIN, Wing Bun LEE, Chi Fai CHEUNG and Suet TO




H. J. Yu et al., "Stiffness Analysis for a Novel Parallel-Robot Based High-Precision Flexible Assembly Fixture", Key Engineering Materials, Vols. 364-366, pp. 327-332, 2008

Online since:

December 2007




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