Clutchless Shifting of Manual Transmission


This novel transmission concept has application for the high-performance vehicle industry.

Problem Addressed

Current hybrid transmission systems sacrifice high-performance operation (e.g. low weight, high speed, smooth acceleration) to increase fuel efficiency and to reduce greenhouse gas emissions of a vehicle. This hybrid transmission concept improves powertrain performance to maintain high-performance operation while facilitating more efficient driving in urban settings.  


The proposed hybrid transmission design features a dual-shaft, clutchless transmission configuration to improve powertrain performance. Powertrain performance improvements result from a clutchless transmission design paired with a speed-matching concept in a hybrid system. A hybrid system uses an electric motor (EM) in unison with an internal combustion engine (ICE) to maintain high-performance operation and fuel efficiency in urban driving.

This transmission design achieves a significant reduction in transmission mass through removal of a clutch and several gears. Additionally, this hybrid design improves transmission efficiency while also reducing inertial, frictional, and mechanical losses. Speed-matching functionality assists the electric motor and allows for clutchless gear shifting. 


  • Significant reductions in transmission mass due to clutchless design
  • Improved fuel efficiency in urban driving
  • Reduction of transmission losses