IDENTIFICATION OF THE BRAKING CHARACTERISTICS OF THE ELASTIC WHEEL OF A MOBILE MACHINE BY ANALYTICAL MEANS

Abstract

The article focuses on the possibilities and means of acceptable high-quality reproduction of the braking process of a car wheel (and a car in general). It is emphasised that the problem of accurate estimation of the coefficient of adhesion
of a pneumatic wheel to the road remains unsolved: the experimental determination of this coefficient, even in artificially created reference road conditions, always leads to significantly ambiguous results. Thus, the braking process tends to
obtain the characteristics of randomness, although, in reality, it is not physically random. Therefore, it is difficult to predict the braking distance, the speed of the start of braking, etc. One of the reasons for such ambiguity is the impossibility to
implement a reliable algorithm that enables qualitatively accurate reproduction of the modes of the usually fast-paced wheel brake control process and, accordingly, a fast-paced realisation of the braking effect. To eliminate this problem, it would be necessary to apply computer simulation modelling of the wheel braking process using the so-called braking characteristic, which must be determined analytically. This satisfactorily flexible analytical description of braking characteristics is proposed in the form of an adaptive dependence of the wheel adhesion coefficient on the road slip coefficient and six so-called regression coefficients. Multiple simulations of the braking process of the wheel (of the car in general) would allow us to identify the regression coefficients of the analytical description and to adequately match all the recorded parameters of each observed braking process.
The proposed methodology can be useful either for optimising the car's braking properties or for improving the quality of road accident examinations.