Non-contact measurement of sculptured surface of rotation

A method for measuring the sculptured surface of rotationby using coordinate measuring machine (CMM) and rotary table is proposed. The measurement is realized during the continuous rotation ofthe workpiece mounted on the rotary table while the probe moves along the generatrix of the surface step by step. This methodpossesses lots of advantages such as simplicity of probe motion, high reliabilityand efficiency. Some key techniques including calibration of the effective radius of the probing system, determination of the position ofaxis of rotation, auto-centering of the workpiece, data processing algorithm, are discussed. Approaches for determining the coordinates on measured surface, establishing workpiece coordinate system and surface fitting are presented. The method can be used with contact or non-contact probes. And some fragile ceramic andplaster parts are measured by using the system consisting of a CMM, rotary table, motorized head and non-contact laser triangulation probe. The measuring uncertainty is about 0.02 mm which meets the