Abstract: The design of shifting rules of vehicle automatic transmission is optimized to improve the overall dynamics of light military wheeled vehicles. According to the simulation environment of MATLAB/Simulink, a vehicle dynamic model based on the two-parameter shifting rule of vehicle speed and throttle opening is constructed. Taking the shift point of the two-parameter shifting rule as the optimization object, the genetic algorithm is used to optimize the shift point. According to the characteristics of that the acceleration parameters can reflect the longitudinal dynamics of vehicle, the acceleration is introduced, and the fuzzy control algorithm is used to dynamically optimize the design of shifting rule, and a three-parameter fuzzy controller is constructed. The simulation model and real vehicle test were used to verify the influence of the shifting rule on vehicle dynamics before and after optimization. The results show that the optimized control strategy can effectively improve the vehicle's dynamic performance, more reasonably allocate the operating conditions of the engine and gear under the power demand, and effectively meet the power demand of military wheeled vehicles under complex road conditions.

Key words: lightcross-countrytacticalvehicle, automatictransmission, shiftingrule, geneticalgorithmoptimization, fuzzycontroloptimization