Analysis of positional tolerance based on the assembly virtual state

Functional gaging techniques can be used to check the conformance of a part with Maximum Material Condition features, but the cost of this gages can be expensive. A Coordinate Measurement Machine can simulate the gage for simple cases. Unfortunately, when the datum reference frame of the feature is not unique, the inspection of the parts defined with MMC using CMM becomes more complex, and it is currently not supported. To resolve this problem a method using a kinematic model is proposed, which simulates the gaging control. The method takes into account the possible rotation of the DRF, and it obtains all possible situations of the DRF for which the parts conforms. And the actual value of the feature can be calculated.