Vehicle systems control for improving stability

• US 8,229,642 B2
• Filed: 01/24/2008
• Issued: 07/24/2012
• Est. Priority Date: 01/25/2007
• Status: Expired due to Fees

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Post, James W. II, Kang, Xiaodi, Monsma, William
• Primary Examiner(s): Black, Thomas G.
• Assistant Examiner(s): LI, CE LI
• Application Number:
  US12/019,341
• Publication Number:
  US 20080183353A1
• Time in Patent Office: 1,643 Days
• Field of Search: 701/37, 701/42, 701/43, 701/38, 701/48, 701 70- 73, 701/79, 701/80, 701 82- 84, 701/91, 180/197, 180/199, 180/233, 303138-140, 303/143, 303/144, 303/146, 303148-150, 280/5.5, 280/5.506, 280/5.507, 280/5.511, 280/5.512, 280/5.515
• US Class Current: 701/91
• CPC Class Codes: B60G 17/0165 to an external condition, e.g. rough road surface, side wind
• CPC Class Codes: B60G 17/0195 characterised by the regulation being combined with other vehicle control systems conjoint control of vehicle sub-units including control of suspension systems B60W10/22
• CPC Class Codes: B60G 17/06 Characteristics of dampers , e.g. mechanical dampersB60G17/015 takes precedence
• CPC Class Codes: B60G 2800/016 Yawing condition
• CPC Class Codes: B60G 2800/212 Transversal; Side-slip during cornering
• CPC Class Codes: B60G 2800/213 by applying forward/backward torque on each wheel individually
• CPC Class Codes: B60G 2800/214 by varying the load distribution
• CPC Class Codes: B60G 2800/215 by applying a braking action on each wheel individually
• CPC Class Codes: B60G 2800/912 Attitude Control; levelling control
• CPC Class Codes: B60G 2800/94 Electronic Stability Program (ESP, i.e. ABS+ASC+EMS)
• CPC Class Codes: B60T 2201/14 Electronic locking-differential
• CPC Class Codes: B60T 2210/12 Friction
• CPC Class Codes: B60T 2260/06 Active Suspension System
• CPC Class Codes: B60T 2270/302 for all-wheel drive vehicles
• CPC Class Codes: B60T 8/17555 specially adapted for enhancing driver or passenger comfort, e.g. soft intervention or pre-actuation strategies
• CPC Class Codes: B60T 8/1769 specially adapted for vehicles having more than one driven axle, e.g. four-wheel drive vehicles
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 10/184 with wheel brakes
• CPC Class Codes: B60W 10/22 including control of suspension systems
• CPC Class Codes: B60W 2710/22 Suspension systems
• CPC Class Codes: B60W 2720/14 : Yaw
• CPC Class Codes: B60W 2720/30 : Wheel torque
• CPC Class Codes: B60W 2720/403 : between front and rear axle
• CPC Class Codes: B60W 30/02 : Control of vehicle driving stability
• CPC Class Codes: B60W 30/18172 : Preventing, or responsive to skidding of wheels
• CPC Class Codes: B60W 40/064 : Degree of grip
• CPC Class Codes: B60W 40/11 : Pitch movement
• CPC Class Codes: B60W 40/112 : Roll movement
• CPC Class Codes: B60W 40/114 : Yaw movement

Abstract

Improved methods of controlling the stability of a vehicle are provided via the cooperative operation of vehicle stability control systems such as an Active Yaw Control system, Antilock Braking System, and Traction Control System. These methods use recognition of road surface information including the road friction coefficient (mu), wheel slippage, and yaw deviations. The methods then modify the settings of the active damping system and/or the distribution of drive torque, as necessary, to increase/reduce damping in the suspension and shift torque application at the wheels, thus preventing a significant shift of load in the vehicle and/or improving vehicle drivability and comfort. The adjustments of the active damping system or torque distribution temporarily override any characteristics that were pre-selected by the driver.

Claims

1. A cooperative Active Damping System (ADS) method for providing enhanced stability of a vehicle travelling on a road, comprising the steps of:

providing an Active Damping System (ADS) for adjusting suspension characteristics on the vehicle;

providing an Antilock Braking System (ABS) on the vehicle;

providing a Traction Control System (TCS) on the vehicle;

providing an Active Yaw Control (AYC) system on the vehicle;

inferring a high coefficient of friction of the road surface when an operational (Activating/Not activating) status of at least one of the TCS and AYC systems is “

Activating” and

a vector representation of the vehicle'"'"'s longitudinal and lateral acceleration is greater than 0.5 g, and inferring a low coefficient of friction of the road surface when the operational status of at least one of the TCS and AYC systems is “

Activating” and

the vector representation of acceleration is below 0.3 g; and

upon inferring a high coefficient of road surface friction, adjusting a damping state of the ADS to a high damping setting; and

upon inferring a low coefficient of road surface friction, adjusting the damping state of the ADS to a low damping setting.

2. The method of claim 1, wherein after a fixed period of time of between 1 and 3 seconds, returning the ADS to a damping state prior to inferring road conditions.

3. The method of claim 1, wherein the adjustments to the damping state of the ADS override a driver pre-selected damping state of the ADS.

4. The method of claim 1, wherein the ADS includes electronically controlled, fast-acting Magneto-Rheological fluid dampers.

5. A method for providing enhanced vehicle stability comprising the steps of:

providing a vehicle with all wheel drive;

providing a Vehicle Stability Assist (VSA) system on the vehicle;

providing a Traction Control system (TCS) on the vehicle;

providing an Active Yaw Control (AYC) system on the vehicle;

inferring a high coefficient of friction of a road surface when an operational (Activating/Not activating) status of at least one of the TCS and AYC systems is On and a vector representation of the vehicle'"'"'s longitudinal and lateral acceleration is greater than 0.5 g and inferring a low coefficient of friction of the road surface when the operational status of each of the TCS and AYC systems is “

Activating” and

the vector representation of acceleration is below 0.3 g; and

upon inferring the coefficient of friction of the road, changing thea distribution of torque amongst vehicle wheels as follows;

if the coefficient of friction is high, implementing a strong side to side and front to rear torque bias; and

if the coefficient of friction is low, implementing a moderate side to side and front to rear torque bias.

6. The method of claim 5, wherein after a fixed period of time between 1 and 3 seconds, returning the distribution of drive torque to a state prior to inferring road conditions.

7. The method of claim 5, wherein changes to the distribution of drive torque overrides any driver pre-selected distribution of drive torque.