Vehicle mass calculation device

• US 6,347,269 B1
• Filed: 07/26/2000
• Issued: 02/12/2002
• Est. Priority Date: 07/26/2000
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toyota Chuo Kenkyusho (Toyota Motor Corporation)
• Original Assignee: Kabushiki Kaisha Toyota Chuo Kenkyusho (Toyota Motor Corporation)
• Inventors: Oshima, Masuji, Yoshida, Hiroyuki, Hayakawa, Kisaburo, Osawa, Masataka
• Primary Examiner(s): Camby, Richard M.
• Application Number:
  US09/625,985
• Time in Patent Office: 566 Days
• Field of Search: 701/29, 701/51, 701/54, 701/70, 702/175
• US Class Current: 701/51
• CPC Class Codes: B60T 2250/02 Vehicle mass
• CPC Class Codes: G01G 19/086 wherein the vehicle mass is dynamically estimated
• CPC Class Codes: G01M 17/007 Wheeled or endless-tracked vehicles G01M17/08 takes precedence

Abstract

To calculate a vehicle mass based on a driving force caused by an engine, running resistance, and vehicle acceleration, influence of gradient resistance is removed. A gross driving force calculating section calculates a gross driving force F of a vehicle by deducting running resistance from a driving force of a vehicle caused by an engine. An acceleration sensor calculates a longitudinal acceleration α of the vehicle. Relationship among a gross driving force F, a longitudinal acceleration α, a vehicle mass M, and road gradient Θ can be expressed as (α=F/M−g sin Θ). Because the change of gradient contains only a low frequency component, by processing a gross driving force F and an acceleration α, using a high-pass filter with a predetermined cut-off frequency, the influence of the gradient Θ can be removed. Based on the resultant processed gross driving force F and the processed acceleration α, a vehicle mass can be obtained from the above expression without being affected by the influence of the gradient

Claims

1. A vehicle mass calculation apparatus, comprising:

acceleration calculating device for calculating a longitudinal acceleration of a vehicle to obtain an acceleration signal;

driving force calculating device for obtaining a driving force signal corresponding to a driving force of a power plant of the vehicle;

first signal processing device for removing influence of resistance acting on the vehicle from the acceleration signal to obtain a processed acceleration signal;

second signal processing device for removing influence of resistance acting on the vehicle from the driving force signal to obtain a processed driving force signal; and

vehicle mass calculating device for calculating a vehicle mass based on the processed acceleration signal and the processed driving force signal.

2. A vehicle mass calculation apparatus according to claim 1, wherein the power plant has a transmission device including a slip transmitting element causing a slip, and a motor, and wherein the driving force calculating device obtains a driving force signal based on transmission torque characteristic of the slip transmitting element with respect to a speed ratio between an input and an output of the slip transmitting element.

3. A vehicle mass calculation apparatus according to claim 2, wherein the slip transmitting element is a torque converter, the transmission torque characteristic is a torque ratio between an input and an output, and the driving force calculating device calculates a driving force of the power plant based on a torque generated by the motor and the torque ratio.

4. A vehicle mass calculation apparatus according to claim 2, wherein the slip transmitting element is a torque converter, the transmission torque characteristic is a torque capacity, and the driving force calculating device calculates a driving force of the power plant based on a pump rotation speed of the torque converter and the torque capacity.

5. A vehicle mass calculation apparatus according to claim 2, wherein the slip transmitting element is a launching clutch, the transmission torque characteristic is a torque ratio between an input and an output, and the driving force calculating device calculates a driving force of the power plant based on a torque generated by the motor and the torque ratio.

6. A vehicle mass calculation apparatus according to claim 2, further, comprising transmission torque characteristic calculating device for calculating the transmission torque characteristic based on a predetermined physical relationship between an input and an output of the transmission device.

7. A vehicle mass calculation apparatus according to claim 1, wherein the first signal processing device is a first high-pass filter for removing a frequency band less than or equal to a predetermined frequency;

and the second signal processing device is a second high-pass filter for removing a frequency band less than or equal to the predetermined frequency.

8. A vehicle mass calculation apparatus, comprising:

acceleration calculating device for calculating longitudinal acceleration of a vehicle to obtain an acceleration signal;

driving force calculating device for obtaining a gross driving force signal corresponding to a gross driving force resulting from a driving force of a power plant of the vehicle deducted by running resistance;

first signal processing device for removing influence of road gradient from the acceleration signal to obtain a processed acceleration signal;

second signal processing device for removing influence of road gradient from the driving force signal to obtain a processed driving force signal;

vehicle mass calculating device for calculating a vehicle mass based on the processed acceleration signal and the processed driving force signal.

9. A vehicle mass calculation apparatus for calculating a mass of a vehicle loaded with a power plant including a motor and a transmission device, comprising:

device for calculating a first physical variable relative to an acceleration calculated by the output rotational speed of the transmission device to obtain a first signal;

device for calculating a second physical amount relative to an input torque of the transmission device to obtain a second signal;

device for storing transmission characteristic of the transmission device;

first signal processing device to remove influence of resistance acting on the vehicle from the first signal to obtain a first processed signal;

second signal processing device to remove influence of resistance acting on the vehicle from the second signal to obtain a second processed signal; and

vehicle mass calculating device for calculating a mass of the vehicle based on the first processed signal and the second processed signal.

10. A vehicle mass calculation apparatus according to claim 9, wherein the transmission device includes a torque converter, the first physical amount is a turbine rotation acceleration of the torque converter, the second physical variable is a pump rotation acceleration of the torque converter, and the transmission characteristic is a torque capacity and a torque ratio of the torque converter.

11. A vehicle mass calculation apparatus according to claim 9, herein the transmission device includes a torque converter, the first physical variable is a turbine rotation acceleration of the torque converter and a wheel rotation acceleration, the second physical variable is a pump rotation acceleration of the torque converter, and the transmission characteristic is a torque capacity and a torque ratio of the torque converter.

12. A vehicle mass calculation apparatus according to claim 9, wherein the transmission device includes a torque converter, the first physical variable is a turbine rotation acceleration of the torque converter and a longitudinal acceleration of the vehicle, the second physical variable is a pump rotation speed of the torque converter, and the transmission characteristic are a torque capacity and a torque ratio of the torque converter.

13. A vehicle mass calculation apparatus according to claim 9, wherein the resistance acting on the vehicle includes running resistance and gradient resistance, the running resistance including rolling resistance and air resistance.

14. A vehicle mass calculation apparatus according to claim 9, wherein the first signal processing device is a first high-pass filter for removing a frequency band less than or equal to a predetermined frequency, and the second signal processing device is a second high-pass filter for removing a frequency band less than or equal to the predetermined frequency..

15. A vehicle mass calculation apparatus, comprising:

acceleration calculating device for calculating a longitudinal acceleration of a vehicle to obtain an acceleration signal;

driving force calculating device for obtaining a driving force signal based on a driving force of a motor;

first signal processing device for removing influence of road gradient from the acceleration signal to obtain a processed acceleration signal;

second signal processing device for removing influence of road gradient from the driving force signal to obtain a processed driving force signal;

vehicle mass calculating device for calculating a vehicle mass based on the processed acceleration signal and the processed driving force signal.

16. A vehicle mass calculation apparatus according to claim 15, wherein the first signal processing device is a first high-pass filter for removing a frequency band less than or equal to a predetermined frequency and the second signal processing device is a second high-pass filter for removing a frequency band less than or equal to the predetermined frequency.