Modern gear design standards do not account for the geometry of asymmetric-tooth gears. Consequently, a conventional symmetric gear design is commonly applied to asymmetric gears featuring different pressure angles on their opposing tooth flanks. This methodology employs a customized asymmetric basic or generating rack to define the tooth geometry. Although technically practical, this approach restricts the full potential benefits that asymmetric gears can offer.

An alternative design approach for asymmetric gears eliminates the reliance on a basic or generating rack in defining gear tooth geometry. The Direct Gear Design method determines the asymmetric gear tooth profile by employing the drive and coast involute flanks derived from two different base circles, separated by the tooth thickness at the reference diameter. Additionally, a tooth tip circle prevents a pointed tooth tip. The optimized tooth root profile aims to minimize bending stress while preventing interference with the mating gear’s tooth tip.