Method and arrangement for propulsion regulation of an automobile

• US 4,765,430 A
• Filed: 10/22/1986
• Issued: 08/23/1988
• Est. Priority Date: 10/24/1985
• Status: Expired due to Term

• Current Assignee: Volkswagen AG
• Original Assignee: Volkswagen AG
• Inventors: Schulze, Bernd-Guido, Lissel, Ernst
• Primary Examiner(s): Love, John J.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US06/922,047
• Time in Patent Office: 671 Days
• Field of Search: 180/197, 180/247, 303/93, 303/95, 303/96, 303/97, 303/98, 303/99, 303/110, 303/111, 364/426
• US Class Current: 180/197
• CPC Class Codes: B60T 8/175 Brake regulation specially adapted to prevent excessive wheel spin during vehicle acceleration, e.g. for traction control safety devices for propulsion unit control responsive to, or preventing, skidding of wheels B60K28/16
• CPC Class Codes: B60T 8/1769 specially adapted for vehicles having more than one driven axle, e.g. four-wheel drive vehicles

Abstract

The invention concerns a method for propulsion regulation of an automobile in the sense of prevention of undesirable spinning of the driven vehicle wheels whereby, as needed, only one of the wheel brakes is activated or the engine torque is reduced. Thereby is determined in the manner of an adaptive regulation in constant repetition from measured rotational speeds and stored vehicle and engine parameters for each driven wheel according to the relation M_u =θ*.Δω, the excess moment causing the spinning of the wheel concerned and subsequently for each of the driven wheels in accordance with the relation M_red =M_u +k(Δω-s) the reduction moment required to eliminate the spinning/tendency to spin, which reduction moment is caused to be applied, depending on each driving situation, either in form of a brake torque in the correct magnitude and/or in form of a reduction of the engine torque in the correct magnitude.

Claims

1. A method for propulsion regulation of an automobile having an engine, revolving driven and non-driven wheels, and wheel brakes associated with the driven wheels, so as to prevent undesirable spinning of the driven wheels, the method comprising the steps of:

detecting the speed of the driven wheels and at least one non-driven wheel;

detecting engine speed;

generating control signals from the detected speed values by means of a digital electronic circuit unit operating with a fixed repetition frequency, said control signals selectively influencing the wheel brakes and a fuel-feeding unit which determines engine torque so as to selectively reduce the engine torque and activate, if necessary, only one wheel brake; and

further comprising the following steps in constant repetition, detecting the speed of the wheels and the engine;

determining from stored vehicle parameters and the detected speeds for each driven wheel an excess driving moment M_u responsible for undesired spinning of the driven wheel concerned according to the relation M_u =θ

*.Δ

ω

, wherein θ

* is the effective mass moment of inertia of a driving train concerned and Δ

ω

is a difference in angular acceleration between the driven wheel concerned and a non-driven wheel;

determining the reduction moment required for preventing spinning and a tendency to spin for each of the driven wheels according to the relation

M_red =M_u +k(Δ

ω

-s), wherein k is a constant, Δ

ω

is the difference in rotational speed between the driven wheel concerned and the non-driven wheel at an instant when reduction of the speed of the driven wheel concerned becomes effective, and s is a predefined desired rotational speed difference between the wheels; and

determining a speed of travel, and if said speed of travel is smaller than a preset speed of travel and if a reduction moment is determined for only one driven wheel of an axle, applying a braking moment to said one driven wheel corresponding to the reduction moment determined, and if said speed of travel is smaller than the preset speed of travel and if a reduction moment is determined for two driven wheels of the axle, on the one hand applying to the wheel to which the larger of both said reduction moments is determined a braking moment corresponding to the difference of the two reduction moments, and on the other hand modifying control of the fuel-feeding unit so that the engine torque is reduced by a valve corresponding to twice the value of the smaller of both said reduction moments, and if said speed of travel is larger than the preset speed of travel, modifying control of the fuel-feeding unit so that the engine torque is reduced by a value corresponding to the sum of both said reduction moments determined.