Progress in Gearshift Schedule for Automotive Stepped Automatic Transmissions

As one of the core control technologies of stepped automatic transmissions (SATs), gearshift schedule directly affects the performance of vehicles equipped with SAT, including drivability, fuel economy, emission, safety, etc. The research progress in gearshift schedule formulation methods are introduced, from the aspects of performance optimization and experience learning, respectively. The research progress in the identification methods of driver’s intention and the quantification methods of performance expectation are summarized from the aspects of gearshift schedule modification, gearshift schedule optimization, etc. The research progress in the driving condition adaptive methodologies for gearshift schedule are analyzed from the aspects of road slope, curve, load, and comprehensive driving conditions. Combined with the development trend of high performance, personalization, and intelligenation, the paper proposes some technical issues regarding gearshift schedule.