Novel CMM-based implementation of the multi-step method for the separation of machine and probe errors

Coordinate measuring machines (CMMs) are subject to periodic verification to ensure measurement capability. However, users also need to rapidly diagnose the source of accuracy degradation to guide corrective actions. This paper presents a novel CMM-based implementation of the multi-step method for the separation of machine and reference sphere errors on one side and triggering probe and probe tip errors on the other. The procedure uses multiple redundancy probing of the machine's own reference sphere and result in a mathematical system similar to that of the multi-step method. The procedure's effectiveness is demonstrated for a variety of stylus lengths and shows its ability to detect changes in lobing errors. A metrological validation is conducted by measuring the errors of the probe and errors of the machine using independent methods. (c) 2010 Elsevier Inc. All rights reserved.