SENSOR OFFSET AMOUNT ESTIMATE DEVICE

• US 20120089297A1
• Filed: 06/03/2009
• Published: 04/12/2012
• Est. Priority Date: 06/03/2009
• Status: Abandoned Application

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Shimizu, Masayuki
• Application Number:
  US13/375,326
• Publication Number:
  US 20120089297A1
• Time in Patent Office: Days
• US Class Current: 701/29.7
• CPC Class Codes: B60W 40/072 Curvature of the road
• CPC Class Codes: B60W 40/076 Slope angle of the road
• CPC Class Codes: B60W 40/10 related to vehicle motion
• CPC Class Codes: G01B 21/22 for measuring angles or tapers; for testing the alignment of axes

Abstract

Provided is a sensor offset amount estimate device capable of accurately estimating the offset amount of a sensor. In a sensor offset amount estimate device, a sensor correction calculation unit estimates the offset amounts of a left and right acceleration sensor, a steering angle sensor, and a yaw rate sensor on the basis of a motion equation considering road camber when a vehicle is turned and traveling information detected by a sensor. Therefore, even when the vehicle travels on the road with road camber, it is possible to accurately estimate the offset amounts of the sensors.

Claims

1. A sensor offset amount estimate device that estimates offset amounts of sensors detecting traveling information of a vehicle, comprising:

an offset amount estimating unit that estimates the offset amount of at least one of a left and right acceleration sensor, a steering angle sensor, and a yaw rate sensor serving as the sensors on the basis of a motion equation considering a road surface cant when the vehicle is turned and the traveling information detected by the sensors.

2. The sensor offset amount estimate device according to claim 1,

wherein the offset amount estimating unit derives, as the motion equation, a yaw rate calculation expression related to a yaw rate of the vehicle and a slip angle calculation expression related to a slip angle of the vehicle and derives a self-aligning torque calculation expression related to a self-aligning torque of the vehicle on the basis of a balance equation of force around a tire of the vehicle, and

the offset amount estimating unit estimates the offset amounts of the left and right acceleration sensor, the steering angle sensor, and the yaw rate sensor from the yaw rate calculation expression, the slip angle calculation expression, the self-aligning torque calculation expression, and the traveling information.

3. The sensor offset amount estimate device according to claim 1,

wherein the offset amount estimating unit derives, as the motion equation, a yaw rate calculation expression related to a yaw rate of the vehicle and a slip angle calculation expression related to a slip angle of the vehicle, and

the offset amount estimating unit estimates the offset amounts of the left and right acceleration sensor and the steering angle sensor from the yaw rate calculation expression, the slip angle calculation expression, and the traveling information.

4. The sensor offset amount estimate device according to claim 1,

wherein the offset amount estimating unit derives a yaw rate calculation expression related to a yaw rate of the vehicle as the motion equation, and

the offset amount estimating unit estimates the offset amount of the left and right acceleration sensor from the yaw rate calculation expression and the traveling information.

5. The sensor offset amount estimate device according to claim 1,

wherein the offset amount estimating unit includes an offset amount correcting unit that corrects the set offset amount of the sensor on the basis of the estimated offset amount of the sensor.

6. The sensor offset amount estimate device according to claim 5,

wherein the offset amount correcting unit varies a rate of change in the offset amount in the correction, depending on the degree of at least one of the steering angle, the slip angle, the yaw rate of the vehicle, and the road surface cant.

7. The sensor offset amount estimate device according to claim 6,

wherein, when the vehicle is turned, the offset amount correcting unit sets the rate of change in the offset amount in the correction to be less than that when the vehicle goes straight, or stops the correction.

8. The sensor offset amount estimate device according to claim 2,

wherein the offset amount estimating unit includes an offset amount correcting unit that corrects the set offset amount of the sensor on the basis of the estimated offset amount of the sensor.

9. The sensor offset amount estimate device according to claim 8,

wherein the offset amount correcting unit varies a rate of change in the offset amount in the correction, depending on the degree of at least one of the steering angle, the slip angle, the yaw rate of the vehicle, and the road surface cant.

10. The sensor offset amount estimate device according to claim 9,

wherein, when the vehicle is turned, the offset amount correcting unit sets the rate of change in the offset amount in the correction to be less than that when the vehicle goes straight, or stops the correction.

11. The sensor offset amount estimate device according to claim 3,

wherein the offset amount estimating unit includes an offset amount correcting unit that corrects the set offset amount of the sensor on the basis of the estimated offset amount of the sensor.

12. The sensor offset amount estimate device according to claim 11,

wherein the offset amount correcting unit varies a rate of change in the offset amount in the correction, depending on the degree of at least one of the steering angle, the slip angle, the yaw rate of the vehicle, and the road surface cant.

13. The sensor offset amount estimate device according to claim 12,

wherein, when the vehicle is turned, the offset amount correcting unit sets the rate of change in the offset amount in the correction to be less than that when the vehicle goes straight, or stops the correction.

14. The sensor offset amount estimate device according to claim 4,

wherein the offset amount estimating unit includes an offset amount correcting unit that corrects the set offset amount of the sensor on the basis of the estimated offset amount of the sensor.

15. The sensor offset amount estimate device according to claim 14,

wherein the offset amount correcting unit varies a rate of change in the offset amount in the correction, depending on the degree of at least one of the steering angle, the slip angle, the yaw rate of the vehicle, and the road surface cant.

16. The sensor offset amount estimate device according to claim 15,

wherein, when the vehicle is turned, the offset amount correcting unit sets the rate of change in the offset amount in the correction to be less than that when the vehicle goes straight, or stops the correction.