Minimum Zone Evaluation of Form Tolerances

Abstract

This paper presents a method to determine from tolerances of a machined part with sampled measurement points from a coordinate measuring machine. The method follows the definitions of the geometric tolerances used in the current ANSI standards. Evaluation of the minimum tolerance zone is formulated as a constrained optimization problem with continuous functional relationships. We apply a general-purpose algorithm for constrained nonlinear optimization. Test cases are given to illustrate successful applications of the method to form features of a straightness, flatness, and roundness. This method is compared with the least square evaluation method.