Vehicle stability control system and method

• US 10,328,915 B2
• Filed: 05/23/2016
• Issued: 06/25/2019
• Est. Priority Date: 01/23/2008
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Lu, Jianbo, Johnson, Leonard K., Meyers, Joseph Carr
• Primary Examiner(s): Nguyen, Bao Long T
• Application Number:
  US15/161,837
• Publication Number:
  US 20160339884A1
• Time in Patent Office: 1,128 Days
• Field of Search: 701 48, 701 70, 701 93- 94, 701 96, 303125, 123349, 123360-361, 123376, 180170, 180172, 477901
• CPC Class Codes: B60K 31/00 Vehicle fittings, acting on a single sub-unit only, for automatically controlling vehicle speed, i.e. preventing speed from exceeding an arbitrarily established velocity or maintaining speed at a particular velocity, as selected by the vehicle operator fittings acting on two or more sub-units B60W30/14; speedometers G01P; systems or devices for controlling speed in general G05D13/00 ; in traffic anti-collision system for road vehicles G08G1/16
• CPC Class Codes: B60T 2201/04 Hill descent control
• CPC Class Codes: B60T 2201/06 Hill holder; Start aid systems on inclined road
• CPC Class Codes: B60T 2230/02 Side slip angle, attitude angle, floating angle, drift angle
• CPC Class Codes: B60T 7/12 for automatic initiation; for initiation not subject to will of driver or passenger limiting speed of vehicles other than rail vehicles B60K31/00
• CPC Class Codes: B60T 7/122 for locking of reverse movement
• CPC Class Codes: B60T 8/1755 Brake regulation specially adapted to control the stability of the vehicle, e.g. taking into account yaw rate or transverse acceleration in a curve road vehicle drive control systems for control of driving stability otherwise than by controlling a particular sub-unit B60W30/02
• CPC Class Codes: B60T 8/17551 determining control parameters related to vehicle stability used in the regulation, e.g. by calculations involving measured or detected parameters
• CPC Class Codes: B60T 8/17552 responsive to the tire sideslip angle or the vehicle body slip angle
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/184 with wheel brakes
• CPC Class Codes: B60W 2510/0225 Clutch actuator position
• CPC Class Codes: B60W 2510/0604 Throttle position
• CPC Class Codes: B60W 2510/1005 Transmission ratio engaged
• CPC Class Codes: B60W 2510/186 Status of parking brakes
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2520/105 Longitudinal acceleration
• CPC Class Codes: B60W 2520/125 Lateral acceleration
• CPC Class Codes: B60W 2520/14 Yaw
• CPC Class Codes: B60W 2520/28 Wheel speed
• CPC Class Codes: B60W 2540/12 : Brake pedal position
• CPC Class Codes: B60W 2552/15 : Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2710/0677 : Engine power
• CPC Class Codes: B60W 30/18118 : Hill holding

Abstract

Various methods of detecting or controlling vehicle stability are disclosed. Certain embodiments provide a method for performing hill hold control for a vehicle, a method for detecting a vehicle sliding into loss of control, and/or a method for controlling a vehicle'"'"'s sliding into loss of control. Methods for detecting sliding into loss of control may include comparing the vehicle'"'"'s longitudinal velocity gradient with a reference speed computed from wheel speed sensors inputs and/or detecting a lateral velocity of the vehicle and a longitudinal velocity of the vehicle when vehicle sliding is detected. Methods for control may include calculating a vehicle pitch angle from the lateral acceleration, the longitudinal acceleration, the yaw rate, the roll rate, and the pitch rate, calculating a longitudinal velocity gradient from the vehicle pitch angle, and/or calculating a sideslip angle.

Claims

1. A method for performing hill hold control for a vehicle, the method comprising:

receiving signals corresponding to a lateral acceleration, a longitudinal acceleration, a yaw rate, a roll rate, and a pitch rate;

calculating a vehicle pitch angle from the lateral acceleration, the longitudinal acceleration, the yaw rate, the roll rate, and the pitch rate;

calculating a road grade from the vehicle pitch angle; and

determining whether to apply a 4-wheel, service braking system of the vehicle based on the road grade, a vehicle speed or wheel speeds, a transmission status, a throttle input, and a brake status.

2. The method of claim 1, wherein determining whether to apply the 4-wheel, service braking system is based additionally on a sideslip angle.

3. The method of claim 2, further comprising detecting, when the vehicle is on a hill, a backsliding of the vehicle, a backward rolling of the vehicle, and/or a forward rolling of the vehicle, based on the road grade, the vehicle speed or wheel speeds, and the sideslip angle.

4. The method of claim 3, wherein determining whether to apply the 4-wheel, service braking system comprises determining whether to apply the 4-wheel, service braking system based on the detection of the backsliding, the backward rolling, and/or the forward rolling.

5. The method of claim 1, wherein determining whether to apply the 4-wheel, service braking system is based additionally on a clutch status.

6. The method of claim 1, further including applying the 4-wheel, service braking system when appropriate until a driver of the vehicle applies brakes or presses throttle when in gear.

7. The method of claim 6, wherein applying the 4-wheel, service braking system when appropriate comprises applying the 4-wheel, service braking system when a controller of the vehicle detects, when the vehicle is on hill, a backsliding of the vehicle, a backward rolling of the vehicle, and/or a forward rolling of the vehicle.

8. The method of claim 1, wherein the lateral acceleration, the longitudinal acceleration, the yaw rate, the roll rate, and the pitch rate are received from a 5-sensor cluster.

9. The method of claim 1, wherein determining whether to apply the 4-wheel, service braking system comprises determining whether to apply an anti-lock braking system.

10. A method for performing hill hold control for a vehicle, the method comprising:

receiving signals corresponding to a lateral acceleration, a longitudinal acceleration, a yaw rate, a roll rate, and a pitch rate;

calculating a sideslip angle based on at least the lateral acceleration;

calculating a vehicle pitch angle from the lateral acceleration, the longitudinal acceleration, the yaw rate, the roll rate, and the pitch rate;

calculating a longitudinal velocity gradient from the longitudinal acceleration, yaw rate, the sideslip angle, and a global pitch angle;

calculating a road grade from the vehicle pitch angle and the global pitch angle;

detecting back sliding using the road grade, a vehicle speed or wheel speeds, a vehicle side slip angle, and the longitudinal velocity gradient; and

applying braking when back sliding is detected.

11. The method of claim 10, wherein the lateral acceleration, the longitudinal acceleration, the yaw rate, the roll rate, and the pitch rate are received from a 5-sensor cluster.

12. A method for performing hill hold control for a vehicle, the method comprising:

receiving signals corresponding to a lateral acceleration, a longitudinal acceleration, a yaw rate, a roll rate, a pitch rate, and wheel speed;

calculating a sideslip angle based on at least the lateral acceleration;

calculating a vehicle pitch angle from the lateral acceleration, the longitudinal acceleration, the yaw rate, the roll rate, and the pitch rate;

calculating a road grade from the vehicle pitch angle and a global pitch angle, when an inclined or decline road grade is calculated;

calculating a longitudinal velocity gradient from the longitudinal acceleration, yaw rate, the sideslip angle, and the global pitch angle;

detecting back sliding using the road grade, a vehicle speed or wheel speeds, the sideslip angle, and the longitudinal velocity gradient;

detecting undesired acceleration of the vehicle using wheel speed; and

applying braking when one or more of back sliding and undesired acceleration is detected, and maintain braking until a driver of the vehicle applies a sufficient level of braking or throttle.

13. The method of claim 12, wherein the lateral acceleration, the longitudinal acceleration, the yaw rate, the roll rate, and the pitch rate are received from a 5-sensor cluster.