The occurrence of singular configurations in parallel mechanisms must be avoided during motion since the actuators cannot control motion even in the neighborhood of these configurations. As a consequence, the knowledge of the singular configurations of the mechanism is important for control purposes, for singularity-free path planning, and also represents basic information for the synthesis of a desired mechanism workspace free from singularities. In this paper the mobility analysis of the 3-UPU parallel mechanism assembled for obtaining a pure translation motion of the output platform is performed and both translation and rotation singularity loci are presented in analytic form and their geometric interpretation is given.

Issue Section:
Technical Papers
Keywords:
manipulator kinematics, actuators, machine control, translational states, constraint theory, Parallel Manipulators, Mobility Analysis, Singularity, Pure Translational Motion
Topics:
Actuators, Mechanical admittance, Parallel mechanisms, Rotation, Manipulators
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