Study On Simulation Of Brake Pedal Feel In A Passenger Car

Brake pedal feel is the subjective feel of the driver and also is one of the importantevaluation of braking performance, it directly affects the braking safety and driving comfortof the vehicle. So the brake pedal feel of hydraulic braking system in a passenger vehicle isstudied in the paper, the analysis method of brake pedal feel based on the simulation test isproposed, and brake pedal feel is improved to make the vehicle more meet the needs of usersand the market.Firstly, the theoretical models of various components in braking system are establishedby studying on the working principle and structure of the braking system’s components andusing the theory of fluid dynamics and mechanical dynamics. On the basis of the parameter ofthe braking system and the vehicle, the simulation models of components of braking systemare established by using AMESim software, and the whole braking system simulation modelalso is established, and the biaxial vehicle model in AMESim is selected. Brake pedal feelrelation curve is obtained by simulation, including the relation curve of brake pedal force,pedal displacement and braking deceleration, and the influence of vacuum booster character,brake master cylinder size and brake wheel cylinder size on brake pedal feel is analyzed.Secondly, the evaluation method of brake pedal feel index is introduced to objectivelyevaluate brake pedal feel. The changes of brake pedal displacement, pedal force and brakingdeceleration in each stage of vehicle braking is comprehensively analyzed through the method,and the parameters which have influence on brake pedal feel can be determined. The relationcurve of brake pedal feel obtained by simulation is compared and analyzed with the curveprescribed by the manufacturer. The brake pedal force of the vehicle does not meet therequirement by analyzing the brake pedal feel of the vehicle.Finally, aiming at the problem, the improved method is proposed. And the objectiveevaluation of unimproved and improved brake pedal feel is compared to verify the feasibilityof the improved method.The research on the changing relation of brake pedal force, pedal displacement andbraking deceleration, the influence factors of brake pedal feel and the set-up of brake pedalfeel in this paper can provide theoretical basis and technical support for the design and matchof braking system and the improvement of brake pedal feel.