Antishudder Gearshift Controller Design for Automatic Transmission

To enhance gearshift quality and the durability of frictional elements, an antishudder gearshift controller design for automatic transmissions is discussed, which both makes turbine speed precisely track the desired trajectory and suppresses the output shaft oscillation. Moreover, these targets are achieved by clutch pressure control only. This paper also considered the model uncertainties of the electrohydraulic control system and disturbance, which are represented by two types of friction characteristics related to temperature, as well as age-related deterioration in automatic transmission fluid and the friction material. Sliding-mode control under the frame of the backstepping technique is used to make the controller robustly adapt to various conditions. In this paper, MATLAB is utilized as the programming environment, and the powertrain system is analyzed in the control-oriented sense. Last, the simulation of 1-2 upshift is illustrated to verify the validity of the proposed controller.