Adapting a braking process

• US 8,812,211 B2
• Filed: 06/05/2013
• Issued: 08/19/2014
• Est. Priority Date: 06/12/2012
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Svensson, Thomas, Moore, Ian, Daniels, Rudolf
• Primary Examiner(s): FREJD, RUSSELL WARREN
• Application Number:
  US13/910,156
• Publication Number:
  US 20130332043A1
• Time in Patent Office: 440 Days
• Field of Search: 701/70, 303/138, 303/155, 303/160, 303/166
• US Class Current: 701/70
• CPC Class Codes: B60T 8/17 Using electrical or electronic regulation means to control braking detecting or indicating faulty operation B60T8/885
• CPC Class Codes: B60T 8/1708 for lorries or tractor-trailer combinations
• CPC Class Codes: B60T 8/1766 Proportioning of brake forces according to vehicle axle loads, e.g. front to rear of vehicle

Abstract

A deceleration of a vehicle is determined based on one or more wheel speeds of the vehicle. A brake pressure of the vehicle is determined. A model of a relationship of the deceleration and the brake pressure is produced. At least one of a vehicle load and a vehicle weight is determined by using the model. The brake pressure is adapted to at least one of the determined vehicle load and the vehicle weight.

Claims

1. A method, comprising:

determining a deceleration of a vehicle based on one or more wheel speeds of the vehicle;

determining a brake pressure of the vehicle;

producing a model of a relationship of the deceleration and the brake pressure;

determining at least one of a vehicle load and a vehicle weight by using the model; and

adapting the brake pressure according to a desired deceleration and at least one of the determined vehicle load and the vehicle weight.

2. The method of claim 1, wherein determining the deceleration includes deriving over time a signal of a wheel speed sensor.

3. The method of claim 1, wherein determining the brake pressure includes using at least one of a pressure signal of a brake master cylinder and a travel signal of a pushrod of the brake.

4. The method of claim 1, wherein producing the model includes placing a desired master cylinder pressure in a relationship with a first derivative of the deceleration over time.

5. The method of claim 4, further comprising defining a target window for the model.

6. The method of claim 5, wherein, when the target window is missed, the desired master cylinder pressure is raised if a rise in the first derivative of the deceleration over time is too low for the determined master cylinder pressure.

7. The method of claim 5, wherein when the target window is missed, the desired master cylinder pressure is lowered if the rise in the first derivative of the deceleration over time is too high for the determined master cylinder pressure.

8. A system comprising a control unit that is configured to:

determine a deceleration of a vehicle based on one or more wheel speeds of the vehicle;

determine a brake pressure of the vehicle;

produce a model of a relationship of the deceleration and the brake pressure;

determine at least one of a vehicle load and a vehicle weight by using the model; and

adapt the brake pressure according to a desired deceleration and at least one of the determined vehicle load and the vehicle weight.

9. The system of claim 8, further comprising a stability control unit that is connected to the control unit.

10. The system of claim 8, further comprising a second control unit for the brake master cylinder, wherein the second control unit is connected to the control unit.

11. The system of claim 8, wherein determining the deceleration includes deriving over time a signal of a wheel speed sensor.

12. The system of claim 8, wherein determining the brake pressure includes using at least one of a pressure signal of a brake master cylinder and a travel signal of a pushrod of the brake.

13. The system of claim 8, wherein producing the model includes placing a desired master cylinder pressure in a relationship with a first derivative of the deceleration over time.

14. The system of claim 13, wherein a target window for the model is defined.

15. The system of claim 14, wherein, when the target window is missed, the desired master cylinder pressure is raised if a rise in the first derivative of the deceleration over time is too low for the determined master cylinder pressure.

16. The system of claim 14, wherein when the target window is missed, the desired master cylinder pressure is lowered if the rise in the first derivative of the deceleration over time is too high for the determined master cylinder pressure.