Estimation Method for Three Dimensional Forms

Abstract

This paper describes a new method for the evaluation of geometrical deviations of the workpieces in three dimensional coordinates measurements. In this method three fundamental geometrical quantities are proposed to express the geometrical conditions, and the geometrical deviations are evaluated by the unbiased standard deviation of the measured coordinate values for these three geometrical quantities. The tolerances specified on the drawings for the workpieces are checked by introducing the new criterion to combine the tolerance and the evaluation factors of the proposed method. The sufficient number of the measuring points on the workpiece required for the processing can also be determined by monitoring the accuracy of the workpiece.