VEHICLE TRACTIVE RESISTANCE CHECKING METHOD Russian patent published in 1999 - IPC

FIELD: transport engineering. SUBSTANCE: invention provides determining aerodynamic drag and rolling resistance of vehicle on dynamic roads of proving grounds both with long and short (600-900 m) measuring sections by retardation method. Method does not require measuring speed or acceleration which are replaced by recording retardation time and accurate marking of route. Retardation method is used for checking on measuring sections separated by intermediate section, length of first measuring section in direction of checking being equal to length of second section. Retardation time is recorded from section borders to moment of stopping and then parameters of resistance to movement are determined basing on relationship between lengths of measuring sections and values of retardation time. Lengths and relative location of measuring sections are chosen to provide minimum discordance in values of difference of each two recorded time values in row. If near measuring sections are separated from each other by noneven and/or nonstraight line sections, measuring sections are divided additionally into lengths with recording of retardation time from their borders and then recording of retardation time is interrupted on intermediate section without interrupting the movement, and retardation time on intermediate section and parameters of resistance are found from two or more relationships of road lengths as a function of recorded retardation time on measuring sections. Moments of passage of measuring section and length borders can be recorded by vehicle crankshaft revolutions with precisely measured rolling radius. EFFECT: provision of high accuracy and reproducibility of results. 3 cl, 11 dwg