The strategic design driven inspection of machined parts

A system for the automatic dimensional inspection of machined industrial parts is under development. Key attributes of the system are its use of design knowledge, i.e. the CAD (computer-aided design) description of the part to be inspected and the strategic use of diverse sensors to generate geometric descriptions of the actual part being inspected as well as the designer's conception of the part. Inspection reduces to the simple comparison of all components of the two models with a correct interpretation of the designer's specified tolerances. Sensors are used in a strategic manner, low-cost sensors, such as those for vision, are used for low-tolerance measurements, and higher-cost sensors, such as coordinate-measuring machines or surface probes, are used to refine object features until all object features have been compared between the CAD model and the actual object being inspected.<>