Position Tolerance Verification Using Simulated Gaging

Abstract

One of the routine manual tasks in dimensional inspection is the assembly verification of circular features by mechanical gaging. With the aid of coordinate measuring machines or vision systems, this task can be performed more efficiently through simulation or soft gaging. A for mulation is presented for interpretation of 2D position tol erance specifications. Simulated gages are constructed from datum features as a set of constraint relationships. The measure of perfect-form position-imperfection is determined as the distance between the measured and the nominal feature positions subject to datum constraint requirements. The derived formulation is applied to an example part with a hole-slot datum-priority frame. This formulation results in a three-variable optimization prob lem that is solved by an augmented Lagrange multipliers technique. The extension of the formulation to 3D is also discussed, but without reference to a specific representa tion.