An Experimental Approach for Determination of Locators Reaction Forces in Milling Fixtures

Document Type : Research Article

Authors

1 Advanced Technologies in Machine Tools Lab, Mechanical Engineering Faculty, Tarbiat Modares University, Tehran, Iran

2 Mechanical Engineering Faculty, Tarbiat Modares University

Abstract

The contact stiffness between the workpiece and fixture locating system is one of the decisive factors for the maintenance of the stability of the workpiece during the machining process. In order to estimate the contact stiffness, it is needed to determine the locator reaction forces. These forces are created by the clamping forces, cutting forces, workpiece weight, and friction effects of the contact between the workpiece and fixture locating system. Some analytical approaches have already been presented for calculating the location reaction forces. However, there are six equations for a 3-2-1 locating system, but 18 unknown parameters. Therefore, an optimization solution is proposed in the literature to obtain the reaction forces which involves several simplifying assumptions which result in considerable errors in the solution. In this study, in addition to presenting the mathematical model of the total system, an experimental approach has been proposed in order to determine the locator reaction forces. This can provide a suitable means for evaluating the optimization solutions and analytical models for determining the locator reaction forces and contact stiffness and diminishing the errors.

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References

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Amirkabir Journal of Mechanical Engineering
Volume 53, Issue 12
March 2022
Pages 5615-5626

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