Gear metrology – An update

Twenty years after the publication of a first CIRP Keynote Paper about gear metrology [32], this paper reviews again the state of the art in this area. Gear technology has changed and improved significantly during the past decades, which initiated substantial improvements in gear metrology, too. On the other hand, for up to 50% of gear inspection technologies used today, only minor changes are observed. Consequently, this update focuses on new or significantly improved techniques, such that only the combination of both this publication and [32] gives a comprehensive review of the state of the art in gear metrology. Gear technology in emerging markets, e.g., electric cars, large gears for energy systems, and micro gear drives, extends the scope of inspection tasks and requires new measuring methods and instruments, including optical sensors. Measured data, covering the entire gear flank of all teeth, need areal flank descriptions, areal evaluation methods, and areal deviation parameters. New calibration methods and artifacts will improve measurement uncertainties.