Vehicle speed estimation device, method and device for detecting decreased tire pressure using the same

• US 20110098882A1
• Filed: 10/06/2005
• Published: 04/28/2011
• Est. Priority Date: 10/07/2004
• Status: Abandoned Application

• Current Assignee: Sumitomo Rubber Industries Limited
• Original Assignee: Sumitomo Rubber Industries Limited
• Inventors: Yanase, Minao, Sugisawa, Toshifumi
• Application Number:
  US11/244,365
• Publication Number:
  US 20110098882A1
• Time in Patent Office: Days
• US Class Current: 701/35
• CPC Class Codes: G01L 17/00 Devices or apparatus for measuring tyre pressure or the pressure in other inflated bodies
• CPC Class Codes: G01M 17/02 Tyres

Abstract

The present invention provides a vehicle-speed estimation device capable of obtaining vehicle speed with high accuracy, thereby simultaneously detecting decrease of air pressure in all wheels by using the vehicle speed. The vehicle-speed estimation device includes means for detecting lateral acceleration of a vehicle, means for detecting a yaw rate of the vehicle, means for detecting a roll angle of the vehicle, and speed estimation and calculation means for estimating vehicle speed from the lateral acceleration, yaw rate and roll angle. Alternatively, the device includes means for detecting lateral acceleration of a vehicle, means for detecting a yaw rate of the vehicle, and speed estimation and calculation means for estimating vehicle speed from the lateral acceleration and the yaw rate. A method for detecting decreased tire pressure includes a step of comparing an estimated vehicle speed with vehicle speed calculated from wheel speed, and a step of determining decreased tire pressure based on a result of the comparison. Alternatively, the method determines decreased tire pressure based on a result of the comparison of a value obtained by multiplying a yaw rate by wheel speed with lateral acceleration.

Claims

1. A vehicle-speed estimation device comprising:

lateral acceleration detecting means for detecting lateral acceleration of a vehicle;

yaw rate detecting means for detecting a yaw rate of the vehicle;

roll angle detecting means for detecting a roll angle of the vehicle; and

speed estimation and calculation means for estimating vehicle speed from the lateral acceleration, yaw rate and roll angle.

2. A vehicle-speed estimation device comprising:

lateral acceleration detecting means for detecting lateral acceleration of a vehicle;

yaw rate detecting means for detecting a yaw rate of the vehicle; and

speed estimation and calculation means for estimating vehicle speed from the lateral acceleration and yaw rate.

3. A program for estimating vehicle speed of a vehicle, which allows a computer to function as speed estimation and calculation means for estimating the vehicle speed from lateral acceleration, yaw rate and roll angle.

4. A program for estimating vehicle speed of a vehicle, which allows a computer to function as speed estimation and calculation means for estimating the vehicle speed from lateral acceleration and yaw rate.

5. A method for detecting decreased tire pressure on a basis of wheel speed obtained from a tire mounted on a vehicle, the method comprising steps of:

detecting wheel speed of each tire;

storing vehicle speed calculated from the wheel speed;

detecting lateral acceleration of the vehicle;

detecting a yaw rate of the vehicle;

detecting a roll angle of the vehicle;

estimating vehicle speed from the lateral acceleration, yaw rate and roll angle;

comparing the estimated vehicle speed with the vehicle speed calculated from the wheel speed; and

determining decreased tire pressure on the basis of a result of the comparison.

6. A method for detecting decreased tire pressure on a basis of wheel speed obtained from a tire mounted on a vehicle, the method comprising steps of:

detecting wheel speed of each tire;

storing vehicle speed calculated from the wheel speed;

detecting lateral acceleration of the vehicle;

detecting a yaw rate of the vehicle;

estimating vehicle speed from the lateral acceleration and yaw rate;

comparing the estimated vehicle speed with the vehicle speed calculated from the wheel speed; and

determining decreased tire pressure on the basis of a result of the comparison.

7. A device for detecting decreased tire pressure on a basis of wheel speed obtained from a tire mounted on a vehicle, the device comprising:

wheel-speed detecting means for detecting wheel speed of each tire;

storage means for storing vehicle speed calculated from the wheel speed;

lateral acceleration detecting means for detecting lateral acceleration of the vehicle;

yaw rate detecting means for detecting a yaw rate of the vehicle;

roll angle detecting means for detecting a roll angle of the vehicle;

speed estimation and calculation means for estimating vehicle speed from the lateral acceleration, yaw rate and roll angle;

comparison means for comparing the estimated vehicle speed with the vehicle speed calculated from the wheel speed; and

pressure-decrease determination means for determining decreased tire pressure on the basis of a result of the comparison.

8. A device for detecting decreased tire pressure on a basis of wheel speed obtained from a tire mounted on a vehicle, the device comprising:

wheel-speed detecting means for detecting wheel speed of each tire;

storage means for storing vehicle speed calculated from the wheel speed;

lateral acceleration detecting means for detecting lateral acceleration of the vehicle;

yaw rate detecting means for detecting a yaw rate of the vehicle;

speed estimation and calculation means for estimating vehicle speed from the lateral acceleration and yaw rate;

comparison means for comparing the estimated vehicle speed with the vehicle speed calculated from the wheel speed; and

pressure-decrease determination means for determining decreased tire pressure on the basis of a result of the comparison.

9. A program for determining decreased tire pressure on a basis of wheel speed obtained from a tire mounted on a vehicle, the program allowing a computer to function as:

storage means for storing vehicle speed calculated from the wheel speed;

speed estimation and calculation means for estimating vehicle speed from lateral acceleration, a yaw rate and roll angle;

comparison means for comparing the estimated vehicle speed with the vehicle speed calculated from the wheel speed; and

pressure-decrease determination means for determining decreased tire pressure on the basis of a result of the comparison.

10. A program for determining decreased tire pressure on a basis of wheel speed obtained from a tire mounted on a vehicle, the program allowing a computer to function as:

storage means for storing vehicle speed calculated from the wheel speed;

speed estimation and calculation means for estimating vehicle speed from lateral acceleration and a yaw rate;

comparison means for comparing the estimated vehicle speed with the vehicle speed calculated from the wheel speed; and

pressure-decrease determination means for determining decreased tire pressure on the basis of a result of the comparison.

11. A method for determining decreased tire pressure with the use of lateral acceleration sensor, a yaw rate sensor and wheel speed sensor mounted on a vehicle, the method comprising steps of:

detecting lateral acceleration by the lateral acceleration sensor;

detecting a yaw rate by the yaw rate sensor;

detecting wheel speed by the wheel speed sensor;

comparing a value obtained by multiplying the yaw rate by the wheel speed with the lateral acceleration; and

determining decreased tire pressure on the basis of a result of the comparison.

12. A device for determining decreased tire pressure, comprising:

lateral acceleration sensor for detecting lateral acceleration of a vehicle;

a yaw rate sensor for detecting a yaw rate of the vehicle;

wheel speed sensor for detecting rotational speed of a wheel mounted on the vehicle;

comparison means for comparing a value obtained by multiplying the yaw rate by the wheel speed with the lateral acceleration; and

pressure-decrease determination means for determining decreased tire pressure on the basis of a result of the comparison.

13. A program for determining decreased tire pressure mounted on a vehicle, the program allowing a computer to function as:

means for inputting lateral acceleration of the vehicle from lateral acceleration sensor;

means for inputting a yaw rate of the vehicle from a yaw rate sensor;

means for inputting wheel speed of the vehicle from wheel speed sensor;

comparison means for comparing a value obtained by multiplying the yaw rate by the wheel speed with the lateral acceleration; and

pressure-decrease determination means for determining decreased tire pressure on the basis of a result of the comparison.