FUEL INDICATOR METHOD

• US 20110010070A1
• Filed: 07/09/2009
• Published: 01/13/2011
• Est. Priority Date: 07/09/2009
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Bohr, Scott, Pierron, Phillip
• Granted Patent: US 8,401,761 B2
• Time in Patent Office: Days
• US Class Current: 701/102
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: G01C 9/06 Electric or photoelectric indication or reading means
• CPC Class Codes: G01F 23/804 containing circuits handling parameters other than liquid level

Abstract

A method for operating a vehicle is provided. The method includes, in one example during a first a rate of change of an inclination of the vehicle, adjusting a fuel level indication based on the inclination and a level of fuel within the fuel tank; and during a second rate of change of the inclination different from the first rate of change, adjusting the fuel level indication based on actual fuel consumption of the engine. In this way, it is possible to provide an accurate fuel level indication based on the inclination when the inclination is not changing too quickly. However, when inclination is changing quickly and may give degraded level readings, it is still possible to provide an accurate fuel level by transiently estimating fuel usage and using, for example, a previous fuel level reading from when the inclination was not changing too quickly.

Claims

1. A method for operating a vehicle including an engine, the method comprising:

during a first a rate of change of an inclination of the vehicle, adjusting a fuel level indication based on the inclination and a level of fuel within the fuel tank; and

during a second rate of change of the inclination different from the first rate of change, adjusting the fuel level indication based on actual fuel consumption of the engine.

2. The method of claim 1, the fuel level indication is adjusted based on the inclination and the level of fuel within the fuel tank while the first rate of change of the inclination of the vehicle is below a threshold value, and the fuel level indication is adjusted based on actual fuel consumption of the engine while the second rate of change of the inclination is above the threshold value.

3. The method of claim 1, wherein the adjustment based on the fuel consumption includes modifying a previous fuel level, the previous fuel level measured while the rate of change was less than the threshold value, the modification based on a pulse width and duration of a plurality of fuel injection events delivered to the engine via at least one fuel injector while the rate of change is above the threshold.

4. The method of claim 1, further comprising while the inclination is below a first threshold value, adjusting the fuel level indication based on the level of the fuel within the fuel tank.

5. The method of claim 1, wherein the fuel level indication is adjusted at an update interval.

6. The method of claim 5, further comprising increasing the update interval when vehicle speed is below a threshold speed value.

7. The method of claim 5, further comprising adjusting the update interval based on the rate of change of the inclination.

8. The method of claim 7, further comprising increasing the update interval when the rate of change of the inclination is below a second threshold value.

9. The method of claim 1, further comprising adjusting the fuel level indication independent of the inclination while the rate of change of the inclination is above the threshold value.

10. The method of claim 1, further comprising adjusting the threshold value of the rate of change of the inclination based on a direction of the inclination, the vehicle having an asymmetrically shaped fuel tank.

11. A vehicle comprising:

an internal combustion engine;

a fuel delivery system coupled to the internal combustion engine, the fuel delivery system including a fuel tank having an in-tank fuel level sensor;

a fuel indicator;

two or more vehicle inclination sensors, the vehicle inclination sensors configured to determine an inclination between a bias plane and a reference plane and a direction of the inclination; and

a control system including memory executable via a processor to;

operate the fuel indicator in an incline mode where the fuel indicator is adjusted based on the inclination, the direction of the inclination, and a level of fuel within the fuel tank; and

operate the fuel indicator in a fuel consumption mode in which the fuel indicator is adjusted based on a current rate of fuel consumption of the vehicle.

12. The system of claim 11, wherein the fuel indicator is operated in the incline mode while a time rate of change of the inclination between the bias plane and the reference plane is below a threshold value and the fuel indicator is operated in the fuel consumption mode while the time rate of change of the inclination is above the threshold value.

13. The system of claim 11, wherein the bias plane is aligned with a surface of the fuel tank.

14. The system of claim 11, wherein the vehicle inclination sensors are accelerometers.

15. The system of claim 14, wherein the accelerometers are utilized in an electronic stability control system configured to actuate at least one vehicle braking mechanism, the throttle, and/or the fuel delivery system when the difference between the vehicle'"'"'s intended course of direction the vehicle'"'"'s actual course of direction is greater than a threshold value.

16. The system of claim 11, further comprising memory executable by a processor to:

operate the fuel indicator in a planar mode in which the fuel indicator is adjusted based on a level of the fuel contained within the fuel tank, while the inclination between the bias plane and a reference plane is below a threshold value.

17. The system of claim 11, wherein the fuel indicator is adjusted at a periodic update interval.

18. The system of claim 17, further comprising code executable to adjust the update interval based on the inclination between the bias plane and the reference plane.

19. The system of claim 18, wherein the update interval is decreased while the time rate of change of the inclination is below a threshold value.

20. A method for operating a vehicle including an internal combustion engine, a fuel delivery system coupled to the internal combustion engine, the fuel delivery system including a fuel tank and an in-tank fuel level sensor disposed within, and two or more vehicle inclination sensors, the method comprising:

while an inclination between a bias plane and a reference plane is below a threshold value, the reference plane substantially parallel to a surface of the fuel within the fuel tank and the bias plane substantially perpendicular to a direction of a gravitational vector of the earth, adjusting a fuel indicator based on a level of the fuel within the fuel tank;

while the inclination between the bias plane and the reference plane is above the threshold value and a time rate of change of the inclination is below a threshold value, adjusting the fuel indicator based on the inclination between the bias plane and the reference plane and the level of the fuel within the fuel tank; and

while the time rate of change of the inclination is above the threshold value, adjusting the fuel indicator based on the rate of fuel consumption of the internal combustion engine; and

adjusting a fuel indicator update interval based on the time rate of change of the inclination between the reference plane and the bias plane.