ABS and/or ASC control system for motor vehicles

• US 6,406,104 B1
• Filed: 10/23/1996
• Issued: 06/18/2002
• Est. Priority Date: 10/23/1995
• Status: Expired due to Term

• Current Assignee: Bayerische Motoren Werke AG
• Original Assignee: Bayerische Motoren Werke AG
• Inventors: Fischer, Gerhard
• Primary Examiner(s): Graham, Matthew C.
• Application Number:
  US08/736,330
• Time in Patent Office: 2,064 Days
• Field of Search: 303/146, 303/147, 303/186, 303/149, 303/177
• US Class Current: 303/146
• CPC Class Codes: B60T 2201/16 Curve braking control, e.g. turn control within ABS control algorithm
• CPC Class Codes: B60T 8/17555 specially adapted for enhancing driver or passenger comfort, e.g. soft intervention or pre-actuation strategies

Abstract

A braking control system for a motor vehicle has an analysis unit for generating a signal proportional to the lateral acceleration of the vehicle and actuators for reducing the brake pressure on at least one wheel during cornering and with a simultaneous brake operation. A symmetrical reduction of the brake pressure is carried out on both wheels of an axle when the amount of the signal proportional to the lateral acceleration is larger than a first lower threshold value.

Claims

1. A braking control system for a motor vehicle having an analysis unit for generating a signal proportional to lateral acceleration of said vehicle and having actuators for reducing the brake pressure on at least one wheel when the vehicle brakes are operated during cornering of the vehicle, wherein:

a symmetrical reduction of brake pressure is carried out on both wheels of an axle when the signal proportional to the lateral acceleration is larger than a first lower threshold value, and martial braking of the vehicle is implemented simultaneously therewith.

2. A braking control system for a motor vehicle having an analysis unit for generating a signal proportional to lateral acceleration of said vehicle and having actuators for reducing the brake pressure on at least one wheel when the vehicle brakes are operated during cornering of the vehicle, wherein:

a symmetrical reduction of brake pressure is carried out on both wheels of an axle when the signal Proportional to the lateral acceleration is larger than a first lower threshold value; and

after a change of signs of the signal proportional to lateral acceleration during a time when vehicle brake operation is maintained, a symmetrical reduction of the brake pressure on both wheels of an axle is thereafter implemented when the signal proportional to lateral acceleration exceeds a second lower threshold value which is smaller than the first lower threshold value, but is larger than zero.

3. Control system according to claim 2 wherein brake pressure on an inside wheel during cornering is reduced by an amount which is greater than a corresponding reduction of brake pressure on an outside wheel during cornering, when the signal proportional to lateral acceleration exceeds a predetermined upper threshold value which amount is larger than the lower threshold values.

4. A braking control system for a motor vehicle having an analysis unit for generating a signal proportional to lateral acceleration of said vehicle and having actuators for reducing the brake pressure on at least one wheel when the vehicle brakes are operated during cornering of the vehicle, wherein:

a symmetrical reduction of brake pressure is carried out on both wheels of an axle when the signal Proportional to the lateral acceleration is larger than a first lower threshold value; and

brake pressure on an inside wheel during cornering is reduced by an amount which is greater than a corresponding reduction of brake pressure on an outside wheel during cornering, when the signal proportional to lateral acceleration exceeds a predetermined upper threshold value which amount is larger than the lower threshold values.

5. A method of controlling brake operation of a motor vehicle, comprising the steps of:

detecting actuation of brakes of said vehicle;

detecting a lateral acceleration of said vehicle;

generating a lateral acceleration signal proportional to lateral acceleration of said vehicle;

comparing said lateral acceleration signal with a plurality of predetermined threshold values;

when a lateral acceleration is detected during an operation of said vehicle brakes in a partial braking mode, implementing a symmetrical reduction of brake pressure on both wheels of an axle of said vehicle when said lateral acceleration signal exceeds a first lower threshold value.

6. A method of controlling brake operation of a motor vehicle, comprising the steps of:

detecting actuation of brakes of said vehicle;

detecting a lateral acceleration of said vehicle;

generating a lateral acceleration signal proportional to lateral acceleration of said vehicle;

comparing said lateral acceleration signal with a plurality of predetermined threshold values;

when a lateral acceleration is detected during an operation of said vehicle brakes, implementing a symmetrical reduction of brake pressure on both wheels of an axle of said vehicle when said lateral acceleration signal exceeds a first lower threshold value;

detecting a change in sign of said lateral acceleration signal; and

following a change in sign of said lateral acceleration signal, implementing a symmetrical reduction of brake pressure on both wheels of an axle of said vehicle when said lateral acceleration signal exceeds a second threshold value which is smaller than said first threshold value but greater than zero, while said vehicle brakes are actuated.

7. Method according to claim 6, comprising the further steps of:

reducing brake pressure on an inside wheel during cornering, by an amount which is greater than a corresponding reduction of brake pressure on an outside wheel during cornering, when the lateral acceleration signal exceeds a predetermined upper threshold value which is larger than the lower threshold values.

8. A method of controlling brake operation of a motor vehicle, comprising the steps of:

detecting actuation of brakes of said vehicle;

detecting a lateral acceleration of said vehicle;

generating a lateral acceleration signal proportional to lateral acceleration of said vehicle;

comparing said lateral acceleration signal with a plurality of predetermined threshold values;

when a lateral acceleration is detected during an operation of said vehicle brakes, implementing a symmetrical reduction of brake pressure on both wheels of an axle of said vehicle when said lateral acceleration signal exceeds a first lower threshold value; and

reducing brake pressure on an inside wheel during cornering, by an amount which is greater than a corresponding reduction of brake pressure on an outside wheel during cornering, when the lateral acceleration signal exceeds a predetermined upper threshold value which is larger than the lower threshold values.