Feature Focus: Asymmetric Gear Design in MASTA 11

Asymmetric gears are an innovative advancement in gear technology, showing various advantages over conventional symmetric gears where gear flanks are unevenly loaded. SMT are pleased to introduce asymmetric gear modelling, analysis and optimisation into our world leading transmission development software, MASTA.

Opposing flanks of cylindrical gears typically experience very different operating conditions. Consider, for example, the vast disparity in loading on the flanks of helicopter rotor gears. Or, the mismatched conditions experienced by the driving and coasting flanks of gears in an automotive transmission.

Having been used in industries employing single flank loading for a number of years, Asymmetric gears are now gaining traction within dual flank applications experiencing substantial differences in load. Asymmetric gears have shown numerous potential benefits over conventional symmetric gear designs. From improved gear lives to enhanced NVH performance, they are a technology which cannot be ignored.

Asymmetric gears can now be modelled, analysed and optimised as part of MASTA’s complete system model and using MASTA’s signature analysis and optimisation tools.

The key difference between symmetric and asymmetric gears is a differing pressure angle on the opposing flanks. This modification aims to improve the performance of one flank at the expense of the other. Perfect for applications where usage is heavily skewed to one side.

The graphic below aims to give you an overview of what you could expect from your asymmetric gear designs.

MASTA facilitates in-depth analysis of these intriguing design options by making use of our Advanced LTCA technology. This well-established method employs the use of FE meshed gears and Hertzian contact models to calculate high fidelity, but rapidly calculated, stiffness models. As a result, users can obtain critical results such as contact patterns and transmission error.

Couple these analysis abilities with MASTA’s powerful gear optimisation tools such as Design Space Search or the Parametric Study Tool and their development need not be as difficult as it appears.

For more information on Asymmetric gears in MASTA or any of MASTA 11’s features, please contact sales@smartmt.com where we will be happy to assist you.

Article by Sam Webster