A full-kinematic model of fixtures for precision locating applications

نویسنده

  • Michael Y. Wang
چکیده

The conventional point-kinematic model of fixtures has only treated point geometry of the contacts between locators and workpiece. However, this model, which ignores the underlying surface properties of the locatorsplus-workpiece system, is inherently incapable of capturing the effects of the geometric properties important to accurate positioning of the workpiece. In this paper, we present a fixture model based on the full kinematics of locatorworkpiece contact. This model incorporates a “virtual” kinematic chain with meshing parameters of contact kinematics. It is shown that the conditions of deterministic localization are related to surface properties of both the workpiece and the locators, including the surface curvature, torsion and scale factors, as opposed to the conventional pointkinematic model. The full-kinematic model developed here has a strong implication for designing fixtures with high locating precision requirements. Keywords— Fixture model, contact and grasp, fixturing, grasping

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تاریخ انتشار 2001