Quality Features for Holistic Evaluation and Quality Control of Micro Face Gears

Micro face gears exhibit complex non-involute flank geometry and lack standardized inspection concepts. In contrast to cylindrical gears, where VDI 2612 provides interpretable profile, flank and pitch characteristics, face gear quality assessment remains fragmented and qualitative. This work presents a feature-based evaluation strategy for micro face gears that transfers cylindrical inspection logic and extends it with dedicated diagnostic features for axial infeed and tangential misalignment. Optical scan data are converted into profile-, flank- and pitch-inspired descriptors within the functional engagement region, establishing a geometric interface between metrology and process parameters in micro-scale hobbing. The strategy is validated on 225 experimentally manufactured face gears with intentionally varied axial infeed, tangential shift and spindle wobble. The results show that these deviation modes can be separated based on their geometric responses, indicating diagnostic capability suitable for virtual metrology and process correction.