Simulation of Gear-shift Algorithm for Automatic Transmission Based on MATLAB

As automobile systems become more and more sophisticated, the need to integrate the science research and engineering software is increasing. As a modeling and simulation software tool, MATLAB can help automobile engineers solve lots of practical problems. Based in vehicle acceleration characteristics, this article introduces a method to get an optimized dynamic 3-parameter gear-shift algorithm of 8-speed automatic transmission through MATLAB programming. The up-shift algorithm is presented at first, following the down-shift algorithm. Moreover, on the basis of MATLAB/SIMULINK, according to the math-model, a simulated modeling of the gear-shift algorithm is made. The vehicle system integration model consists of engine, hydraulic torque converter, gearbox, gear-shift algorithm with its control system, and vehicle body dynamic system. Finally, the focus is in particular on the dynamic performances of the simulated model to analyze how the vehicle operates under the gear-shift algorithm. The calculated and simulated result indicates that the work can predict the gear-shift performance of the target vehicle successfully.