The estimation of friction coefficient of brake pad- disc during braking process in different operating conditions

Abstract

In the paper, the results of the research were discussed, the aim of which was the estimation of the friction coefficient of brake pad- brake disc during braking a vehicle with regard to the influence of external conditions. B Segment vehicle with independent suspension was used for measurement and tests. Test brakes were made on the drum test stand the moment of inertia of which was chosen so that kinetic energy lost during the test would be the same as during road tests. The step of wetting of the brake disc and pads was taken into consideration during the research. The research was conducted comparatively for the vehicle with acting anti-lock braking system and subsequently for the vehicle without the system. The friction materials used in disc brake systems are required to provide a stable friction coefficient. From the point of view of efficiency of operation the brake system, the characteristics of the variation of friction coefficient of the brake disc and pads have a special meaning. Neural network was applied to estimate the value of friction coefficient during braking. The results obtained during the measurements were compared to the estimated values.