A Model for the Prediction of Reaction Forces in a 3-2-1 Machining...

Prior knowledge of fixture reaction forces allows the fixture designer to better analyze fixture performance with regard to adequate force restraint, workpiece displacement, and workpiece damage. This paper describes the formulation and solution of a model for predicting the normal and frictional reaction forces between rigid fixture elements and an elastic workpiece due to clamping and machining forces. The model is based on closed-form solutions for an elastic half-space subjected to distributed normal and tangential loads. Model predictions are shown to be in good agreement with measured reactions when only clamping loads are considered. Preliminary results for machining loads show larger deviations between model predictions and measured reactions. Explanations for these deviations are given. Authors: Jose F. Hurtado, Shreyes N. Melkote, Georgia Institute of Technology, Atlanta, GA.