Recursive vehicle mass estimation system

• US 6,438,510 B2
• Filed: 12/22/2000
• Issued: 08/20/2002
• Est. Priority Date: 04/23/1998
• Status: Expired due to Term

• Current Assignee: Cummins Incorporated
• Original Assignee: Cummins Incorporated
• Inventors: Bailey, Thomas L., Taylor, Dennis O., Zhu, G. George
• Primary Examiner(s): NOLAND, THOMAS
• Application Number:
  US09/748,050
• Publication Number:
  US 20010001138A1
• Time in Patent Office: 606 Days
• Field of Search: 702/175, 738/65, 701/102, 701/1
• US Class Current: 702/175
• CPC Class Codes: B60T 2250/02 Vehicle mass
• CPC Class Codes: B60T 8/172 Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters B60T8/17551 takes precedence
• CPC Class Codes: G01G 19/086 wherein the vehicle mass is dynamically estimated

Abstract

A method and apparatus is disclosed for recursively estimating vehicle mass and/or aerodynamic coefficient of a moving vehicle. The vehicle speed and push force data are collected and a segment of qualified data is then selected from the collected data. Newton'"'"'s second law is integrated to express vehicle mass and/or aerodynamic coefficient in terms of vehicle push force and vehicle speed. This expression is then used in a recursive analysis of the qualified data segment to determine an estimated vehicle mass and/or aerodynamic coefficient.

Claims

1. A system, comprising:

a vehicle including an engine with a fueling system, a transmission coupled to said engine having a plurality of engageable gear ratios, a drive axle, and a propeller shaft coupling said transmission to said drive axle;

a vehicle speed sensor, said sensor providing a speed signal corresponding to speed of the vehicle;

a programmable processor with a memory portion operatively coupled thereto, said processor being responsive to an engine fueling rate signal and a gear ratio signal stored in said memory to determine a vehicle push force corresponding to said speed signal, said processor being programmed to qualify a data segment from vehicle speed and vehicle push force to calculate an estimated vehicle mass, said estimated vehicle mass being determined by a recursive analysis of said data segment and establishing said vehicle speed as a function of said push force.

2. The system of claim 1, further including a throttle percentage stored in said memory corresponding to said vehicle speed and vehicle push force, said data segment not being qualified when said throttle percentage is less than a threshold requirement.

3. The system of claim 2, wherein said threshold requirement is a throttle percentage of 30%.

4. The system of claim 1, wherein qualification of said data segment includes establishing a torque percentage exceeding a threshold amount.

5. The system of claim 1, wherein qualification of said data segment includes establishing a brake status.

6. The system of claim 1, wherein said data is not qualified if a gear is not presently engaged.

7. The system of claim 1, wherein said processor is operable to further calculate an estimated vehicle aerodynamic coefficient from said function.

8. The system of claim 1, wherein said processor is further operable to correct said estimated vehicle mass and aerodynamic coefficient when one of said estimates is outside an upper or lower limit.

9. The system of claim 1, further including a data communications link connected to said processor, and any of said engine fueling rate signal, said vehicle speed signal or said gear ratio signal being provided to said processor from a remote processor via said data communications link.

10. The system of claim 1, wherein said processor is further operable to sense an engine fueling to determine an engine torque, convert the engine torque to a tire torque based on an engaged gear ratio, and convert the tire torque to the vehicle push force.

11. The system of claim 1, further comprising:

means for determining an engine fueling rate and providing said engine fueling rate signal corresponding thereto; and

means for determining a presently engaged gear ratio of said transmission and providing said gear ratio signal corresponding thereto.

12. The system of claim 1, wherein said vehicle speed sensor senses the rotational speed of a vehicle component to provide said speed signal.

13. The system of claim 1, wherein said data segment is selected by said processor from a longest segment of buffered qualified data including said vehicle speed and said vehicle push force.

14. The system of claim 1, wherein said processor is operable to provide a control signal based on said estimated vehicle mass.

15. A system, comprising:

a vehicle including an engine with a fueling system, a transmission coupled to said engine having a plurality of engageable gear ratios, a drive axle, and a propeller shaft coupling said transmission to said drive axle;

a vehicle speed sensor, said sensor providing a speed signal corresponding to speed of the vehicle;

a programmable processor with a memory portion operatively coupled thereto, said processor being responsive to an engine fueling rate signal and a gear ratio signal stored in said memory to determine a vehicle push force corresponding to said speed signal, said processor being programmed to calculate an estimated vehicle mass from said vehicle speed and said vehicle push force data, said estimated vehicle mass being determined by a recursive analysis of said data and establishing said vehicle speed as a function of said push force.

16. The system of claim 15, wherein said processor is further programmable to qualify a data segment of said vehicle speed and said vehicle push force.

17. The system of claim 16, wherein said data segment is selected by said processor from a longest segment of buffered qualified data including said vehicle speed and said vehicle push force.

18. The system of claim 16, further including a throttle percentage stored in said memory corresponding to said vehicle speed and said vehicle push force, said data segment not being qualified when said throttle percentage is less than a threshold requirement.

19. The system of claim 16, wherein said data segment is not qualified unless a torque percentage exceeds a threshold amount.

20. The system of claim 16, wherein said data segment is not qualified if a brake of said vehicle is engaged.

21. The system of claim 16, wherein said data segment is not qualified if a gear is not presently engaged.