US5634698A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for controlling brake pressure based on fuzzy logic using steering angle and yaw speed
Assignee: Robert Bosch GmbH
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Filing: 1995-02-21
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Granted: 1997-06-03
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Expires: 2015-02-21
Abstract
Abstract An ABS which evaluates slip values prescribes pressure values for the wheel brakes. In order to improve the driving stability, these pressure values are varied by a brake controller using the deviation of the yawing speed from a set value and the front-axle steering angle as input variables. The brake controller determines its output values (variation values) with the aid of the fuzzy logic. Additionally, rear-axle steering is integrated into the system, the system partially also using fuzzy logic. Subsequently, an adaptation which is based on fuzzy logic and uses the brake controller and the rear-axle steering controller in a weighted fashion is proposed.
Inventors
- 👤 Chi-Thuan Cao
- 👤 Rolf Becker
- 👤 Ulrich Belzner
- 👤 Thorsten-Wilhelm Moeller
- 👤 Bernd Lieberoth-Leden
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 02:28
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/17; B60T8/174; B60T8/1755; B62; B62D; B62D7/00; B62D7/06; B62D7/14; B62D7/15; B62D7/159; B60T2260/00; B60T2260/02; B60T2260/022
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
151 words
Vehicle dynamics control system for a vehicle having wheels, said system comprising means for determining desired slip values λ is for said wheels, means for determining actual slip values λ i at said wheels, an antilock controller which determines first desired pressure values P is by comparing said actual slip values λ i to said desired slip values λ is , means for determining the front axle steering angle δ, means for determining the yaw speed w, a fuzzy logic brake controller which determines correction values ΔP is in dependence on the front steering angle δ and the yaw speed w, adding means for determining second desired pressure values P* is according to P* is =P is +ΔP is , a pressure controller for generating brake pressure control signals in dependence on said second desired pressure values P* is , and brake control valves responsive to said brake pressure control signals.
Claim 2
Dependent Claim
151 words
Vehicle dynamics control system for a vehicle having wheels, said system comprising means for determining desired slip values λ is for said wheels, means for determining actual slip values λ i at said wheels, an antilock controller which determines first desired pressure values P is by comparing said actual slip values λ i to said desired slip values λ is , means for determining the front axle steering angle δ, means for determining the yaw speed w, a fuzzy logic brake controller which determines correction values ΔP is in dependence on the front steering angle δ and the yaw speed w, adding means for determining second desired pressure values P* is according to P* is =P is +ΔP is , a pressure controller for generating brake pressure control signals in dependence on said second desired pressure values P* is , and brake control valves responsive to said brake pressure control signals.
Claim 3
Dependent Claim
20 words
The vehicle dynamic control system as claimed in claim 1, wherein the said system additionally comprises a rear-axle steering controller.
Claim 4
Dependent Claim
94 words
The vehicle dynamic control system as claimed in claim 2, wherein the rear-axle steering controller is a model-following controller with a control component and a fuzzy logic steering controller, the control component producing a first desired rear-axle steering angle δ hs which depends on the front-wheel steering angle δ and the yawing speed w, and the fuzzy logic steering controller producing a correction value Δδ hs from which a second desired value δ* hs =δ hs +Δδ hs is produced, and wherein the set value is desired by means of a steering angle controller.
Claim 5
Dependent Claim
59 words
The vehicle dynamic control system as claims in claim 3 wherein said fuzzy logic brake controller modifies the correction value ΔP is by means of weighting value dK3 BRG for braking, and said fuzzy logic steering controller modifies the correction value Δδ hs by means of weighting value dK3 for steering, the weighting values lying between 0 and 1.
Claim 6
Dependent Claim
21 words
The vehicle dynamic control system as claimed in claim 4, wherein the weighting values are determined by means of fuzzy logic.
Claim 7
Dependent Claim
123 words
The vehicle dynamic control system as claimed in claim 1 further comprising means for determining the vehicle speed, means for determining desired yaw speed w ref based on the front axle steering angle δ and the vehicle speed, and means for generating an input variable e=w ref -w for said fuzzy logic brake controller, said fuzzy logic brake controller standardizing said input variable e in a range from -1 to +1 and dividing it into the following four fuzzy symmetrical sets: e n =NB (negative big) e n =NS (negative small) e n =PS (positive small) e n =PB (positive big), said fuzzy logic brake controller determining said correction values ΔP is in dependence on said standardized input vehicle variable e n .
Claim 8
Dependent Claim
101 words
The vehicle dynamic control system as in claim 6 wherein said fuzzy logic brake controller determines an output variable BRA based on said standardized input variable e n and said front axle steering angle δ, and standardizes said output variable BRA in a range from BRA min to BRA max and divides it into the following four fuzzy symmetrical sets BRA N =NB (negative big) BRA N =NS (negative small) BRA N =PS (positive small) BRA N =PB (positive big) said fuzzy logic brake controller determining said correction values ΔP is in dependence on said standardized output variable BRA N .
Claim 9
Dependent Claim
151 words
Vehicle dynamics control system for a vehicle having wheels, said system comprising means for determining first desired slip values λ is for said wheels, means for determining actual slip values λ i at said wheels, means for determining the front axle steering angle δ, means for determining the yaw speed w, a fuzzy logic brake controller which determines correction values Δλ is in dependence on the front steering angle δ and the yaw speed w, adding means for determining second desired slip values λ* is according to λ* is =λ is +Δλ is , an anti-lock controller which determines desired pressure values P is by comparing said actual slip values λ i with said second desired slip values λ* is , a pressure controller for generating brake pressure control signals in dependence on said desired pressure values P is , and brake control valves responsive to said brake pressure control signals.
Claim 10
Dependent Claim
151 words
Vehicle dynamics control system for a vehicle having wheels, said system comprising means for determining first desired slip values λ is for said wheels, means for determining actual slip values λ i at said wheels, means for determining the front axle steering angle δ, means for determining the yaw speed w, a fuzzy logic brake controller which determines correction values Δλ is in dependence on the front steering angle δ and the yaw speed w, adding means for determining second desired slip values λ* is according to λ* is =λ is +Δλ is , an anti-lock controller which determines desired pressure values P is by comparing said actual slip values λ i with said second desired slip values λ* is , a pressure controller for generating brake pressure control signals in dependence on said desired pressure values P is , and brake control valves responsive to said brake pressure control signals.
Claim 11
Dependent Claim
122 words
The vehicle dynamic control system as claimed in claim 8 further comprising means for determining the vehicle speed, means for determining desired yaw speed w ref based on the front axle steering angle δ and the vehicle speed, and means for generating an input variable e=w ref -w for said fuzzy logic brake controller, said fuzzy logic brake controller standardizing said input variable e in a range from -1 to +1 and dividing it into the following four fuzzy symmetrical sets: e n =NB (negative big) e n =NS (negative small) e n =PS (positive small) e n =PB (positive big), said fuzzy logic brake controller determining said correction values Δδ is in dependence on said standardized input variable e n .
Claim 12
Dependent Claim
101 words
The vehicle dynamic control system as in claim 9 wherein said fuzzy logic brake controller determines an output variable BRA based on said standardized input variable e n and said front axle steering angle δ, and standardizes said output variable BRA in a range from BRA min to BRA max and divides it into the following four fuzzy symmetrical sets BRA N =NB (negative big) BRA N =NS (negative small) BRA N =PS (positive small) BRA N =PB (positive big) said fuzzy logic brake controller determining said correction values Δλ is in dependence on said standardized output variable BRA N .
Claim 13
Dependent Claim
20 words
The vehicle dynamic control system as claimed in claim 8, wherein the said system additionally comprises a rear-axle steering controller.
Claim 14
Dependent Claim
94 words
The vehicle dynamic control system as claimed in claim 11, wherein the rear-axle steering controller is a model-following controller with a control component and a fuzzy logic steering controller, the control component producing a first desired rear-axle steering angle δ hs which depends on the front-wheel steering angle δ and the yawing speed w, and the fuzzy logic steering controller producing a correction value Δδ hs from which a second set value δ* hs =δ hs +Δδ hs is produced, and wherein the desired value is set by means of a steering angle controller.
Claim 15
Dependent Claim
57 words
The vehicle dynamic control system as claimed in claim 12 wherein said fuzzy logic brake controller modifies the correction value Δλ is by means of weighting dK3 - BRG for braking, and said fuzzy logic steering controller modifies the value Δδ hs by the weighting value dK3 for steering, the weighting values lying between 0 and 1.
Claim 16
Dependent Claim
21 words
The vehicle dynamic control system as claimed in claim 13, wherein the weighting values are determined by means of fuzzy logic.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-06-02 | 2000-12-02 | 2001-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-06-02 | 2004-12-02 | 2005-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-06-02 | 2008-12-02 | 2009-06-03 | $7700.00 | Window Closed / Lapsed |