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Indexed by:期刊论文

Date of Publication:2016-11-01

Journal:MECHANISM AND MACHINE THEORY

Included Journals:SCIE、EI、Scopus

Volume:105

Page Number:369-387

ISSN No.:0094-114X

Key Words:Asymmetrical spherical parallel manipulator; Motion/force transmission; Transmission wrench screw; Stiffness; Universal joint

Abstract:This paper presents a comparative study of asymmetrical spherical parallel manipulators with respect to motion/force transmission and stiffness. The manipulators adopt a center shaft to both generate a decoupled unlimited-torsion motion and support the mobile platform for high positioning accuracy, where the difference lies in the rotationally/linearly actuated limbs in-parallel. The transmission indices are defined based on the virtual coefficient between the transmission wrench and twist screws for design analysis. Comparison of the manipulators is carried out based on a multi-objective optimization approach, which aims to maximize the workspace of high transmissibility and stiffness over a regular workspace. Performance isocontours are visualized to highlight the advantages/drawbacks among the manipulator counterparts. (C) 2016 Elsevier Ltd. All rights reserved.