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Title: On the kinematic design of spherical three-degree-of-freedom parallel manipulators

Journal Article · · International Journal of Robotics Research; (United States)

This article studies the kinematic design of different types of spherical three-degree-of-freedom parallel manipulators. The mechanical architectures presented have been introduced elsewhere. However, designs having at least one isotropic configuration are suggested here for the first time. Isotropic configurations are defined, in turn, as those configurations in which the Jacobian matrix, mapping the angular velocity vector of the effector into the joint velocities, is proportional to an orthogonal matrix. First, a review of the direct and inverse kinematics of spherical three-degree-of-freedom parallel manipulators is outlined, and a general form for the Jacobian matrix is given. Parallel manipulators with revolute or prismatic actuators are discussed. Then, the concept of kinematic conditioning is recalled and used as a performance index for the optimization of the manipulators. It is shown that this leads to designs having at least one isotropic configuration. Finally, a few examples of such designs are presented. 15 refs.

OSTI ID:
5692121
Journal Information:
International Journal of Robotics Research; (United States), Vol. 12:4; ISSN 0278-3649
Country of Publication:
United States
Language:
English