Static and Dynamic Transmission Error and Vibration Characteristics of a Steel–Carbon‐Fiber‐Reinforced Polymer Hybrid Spur Gear

Steel–carbon‐fiber‐reinforced polymer (CFRP) hybrid gears combine metallic teeth with a lightweight composite web. This study compares a solid steel gear, a web‐drilled lightweight steel gear, and a steel–CFRP hybrid spur gear through analytical modeling, finite element simulations, and closed‐loop bench tests. The hybrid gear reduces mass by approximately 50%. The simulations predict lower natural frequencies for the three modes examined and a higher mean static transmission error (STE), while the cyclic STE variation remains broadly comparable in the plotted results. Under the tested operating conditions, the hybrid gear exhibits lower vibration acceleration and measured sound pressure level, together with a smaller reported dynamic transmission error (DTE) fluctuation. At 1000 r/min and 15 N·m, the measured mesh‐frequency acceleration peak is 71.8% lower than that of the solid steel gear. The contribution is the combined comparison of quasi‐static compliance and operating dynamic response, rather than a new hybrid architecture. The observed dynamic improvements are consistent with modified rim‐to‐hub vibration‐transfer characteristics, alongside potential contributions from structural compliance redistribution and composite/interfacial energy dissipation.