Modeling and Analysis between In-Process CNC Touch ProbeGauging and Post-Process CMM Inspection

摘要

In-process part inspection using a spindle touch probe has gained a significant importance, mainly because parts canrnstay on the machine without disrupting the machine setup while inspection is being conducted. This practice leads torna shorter inspection time, improved part accuracies, and reduction of scraps. Recently, intense domestic andrninternational competition has put more importance on part quality in terms of producing parts right the first time andrnmaintaining the consistent quality standards. A literature review revealed that a comparative analysis between inprocessrngauging using a touch probe and post-process inspection using a coordinate measuring machine (CMM) tornascertain part quality has not been adequately studied. Therefore, there is a need for a study to measure therncharacteristics of the two inspection techniques. To address the problem, cutting experiments were conducted andrnmeasurement data were analyzed using a state-of-the-art CNC machine, a CMM, a touch probe, and a highprecisionrnballbar system. The experimental data show that machined features and touch probe measurements arernaffected by the inherent shortcomings in machine tool structures, suggesting a machine tool capability analysis bernundertaken in tune with the required tolerance specifications prior to machining operations, rather than solelyrnrelying on the touch probe inspection for part quality assessment.