Design of an Electric Motor Transmission System Without Friction Synchronization

Abstract

Copyright © 2019 ASME. This paper investigates the design of a new transmission system without a friction synchronizer for high-performance hybrid vehicles. Manual and automated manual transmission systems traditionally use friction synchronizers to facilitate smooth transitions during a gearshift, ensuring speed matching and proper engagement of the gears. Active position sensing technology for dogteeth is being developed, along with the potential of speed matching using electric motors, eliminating the need for the friction synchronizer. However, in removing these friction synchronizer components, significant shock could be introduced to the transmission system with speed or position errors during a shift. This paper proposes a solution through a gear system that utilizes a face mesh design, torsional springs, and alternating teeth height. A prototype of this design was created and successfully tested as a proof of concept for a transmission system, which has the potential to improve hybrid, automated manual transmission design.