Abstract
In a conventional manual transmission for any road car, the gear ratio pattern turns out to be wider in the initial gears and closer as it progresses. As the gear ratios are wider the elasticity of each gear increases leading to drop in acceleration. But in the case of a sport car the power transmission comes with a close ratio gearbox. The latter one cannot be used to drive in traffic or city because of frequent gear shift requirement. In this paper, we formulated a method by having both kinds of transmission i.e. close ratio and wide ratio. By carefully controlling the gear selection and shift points we can achieve both fuel economy and acceleration based on requirements. This strategy is executed with the help of Automated Manual Transmission(AMT) and Transmission Control Unit(TCU) to closely control shifts and reduce driver effort. The controller model was integrated with vehicle dynamics model to check the working of the shift demand and itseffect on vehicle performance. The AMT offers three different driving modes namely, ECO, SPORT and Manual. The first two modes come under the driver assistance mode where, AMT takes complete control of the vehicle and vary the gear selection and shift points based on mode. The initial phases of testing were based on maneuver from default driver model (IPG Driver) of CarMaker. Adding to this the real time driver input was fed to CarMakerusing a Real-time driver maneuverer kit (Logitech G27) to bridge the gap between simulation with IPG driver and actual driving conditions.
Keywords: Adaptive Gearbox, Shift points, Automated Manual Transmission (AMT), Gear Ratio, Transmission Control Unit (TCU).