Spatial Harmonic Analysis of Production Gear Pitch Reports with Accumulation Weighting, Digitization Sensitivity, and Population Descriptors

Production pitch inspection retains circumferential traces, but scalar tolerance summarizes and discards their spatial organization. This study evaluates a report-based metrology workflow on 65 raster inspection reports from 59 unique z = 23 gears. Analytical accumulation weighting, circular first-differencing and the directly reported single-pitch trace provide distinct checks of representation dependence. A fully specified extraction rerun and 17 alternative settings assess waveform, sampling, and overlay sensitivity. In the revised baseline, the lowest two harmonics dominate 54/59 direct-pitch spectra, although exact descriptor values and component rankings depend on baseline exclusion and trace selection. The five-descriptor Spearman matrix and principal component analysis show substantial redundancy: two components explain 92.0% of standardized variance and the participation-ratio dimension is 1.81. Representation and descriptor ablations quantify information retained by reduced summaries. Descriptor calculation is inexpensive relative to report decoding, but timing does not establish production readiness. The contribution is a reproducible analysis of reported pitch topology; manufacturing, clamping, measurement and correction effects cannot be separated without native numerical data and controlled metrology records.