Title: Anti-slip regulator system (ASR)

Authors: B.-G. Schulze, E. Lissel

Addresses: Volkswagen AG, Forschung Fahrzeugtechnik, Wolfsburg, Germany. ' Volkswagen AG, Forschung Fahrzeugtechnik, Wolfsburg, Germany

Abstract: When wheelspin occurs the anti-slip regulator system (ASR) regulates the drive torque in such a way that steerability is always retained, together with good forward traction. The microprocessor which performs the regulating function compares the wheel speed increase at each driven wheel with the vehicle acceleration, and calculates the |excess torque| which is causing wheelspin, and eliminates it automatically by briefly actuating the wheel brake and/or by backing off the throttle. At low speeds the wheel with the greatest amount of wheelspin is slowed by an exactly calculated brake application with a simultaneous reduction of engine power, so that the amount of forward traction is determined by the greatest available surface adhesion. At higher speeds, however, in order to avoid undesired yaw reactions, the system operates only by reducing engine power delivery by the necessary amount, which means that the amount of tractive force is determined by the lower surface adhesion value in each case.

Keywords: anti-slip regulator system; directional stability; front-wheel drive; microprocessor; sensors; steerability; vehicle handling; wheel slip; wheelspin; drive torque; vehicle design.

DOI: 10.1504/IJVD.1987.061191

International Journal of Vehicle Design, 1987 Vol.8 No.1, pp.60 - 73

Published online: 25 May 2014 *

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