Method for correcting the outputs of vehicle behavior sensor

• US 20060142920A1
• Filed: 12/16/2005
• Published: 06/29/2006
• Est. Priority Date: 12/24/2004
• Status: Active Grant

• Current Assignee: Advics Company Limited (Aisin Corp.)
• Original Assignee: Advics Company Limited (Aisin Corp.)
• Inventors: Hashiba, Hitoshi
• Granted Patent: US 7,613,567 B2
• Time in Patent Office: Days
• US Class Current: 701/70
• CPC Class Codes: B60T 2250/06 Sensor zero-point adjustment; Offset compensation
• CPC Class Codes: B60T 8/368 combined with other mechanical components, e.g. pump units, master cylinders
• CPC Class Codes: G01C 21/183 Compensation of inertial measurements, e.g. for temperature effects
• CPC Class Codes: G01C 25/005 initial alignment, calibration or starting-up of inertial devices
• CPC Class Codes: G01P 15/18 in two or more dimensions
• CPC Class Codes: G01P 21/00 Testing or calibrating of apparatus or devices covered by the preceding groups

Abstract

First and second acceleration sensor elements for detecting the acceleration of a vehicle in the direction in which the vehicle travels, and the acceleration of the vehicle in the direction transverse to the travel direction of the vehicle are mounted on a sensor substrate which is mounted on a control substrate of a vehicle control device. With the sensor substrate positioned such that the sensing directions of the respective sensor elements are perpendicular to or parallel to the vertical line, the outputs of the respective sensor elements are detected as zero errors or gain errors. The sensor substrate is then mounted on a vehicle and with the vehicle placed on a horizontal surface, a signal is sent to an electronic control unit (ECU) of the vehicle control device so that the ECU can recognize that the vehicle is horizontal. Based on the outputs from the first and second sensor elements at this time, the deviation angles of the sensor elements about the X-axis and Y-axis directions are calculated. The acceleration in the X-axis direction is calculated from signals from wheel speed sensors. Based on the deviation angles and the acceleration in the X-axis direction, the deviation angle of the sensor elements about the Z-axis is calculated. Based on the thus calculated deviation angles and zero errors and/or gain errors, the outputs of the sensor elements are corrected to obtain true accelerations in the X-axis and Y-axis directions.

Claims

1. A method for correcting outputs of a vehicle behavior sensor assembly of a vehicle control device including an electronic control unit, said vehicle behavior sensor assembly comprising a first acceleration sensor element for detecting an acceleration of a vehicle on which said vehicle control device is mounted in an X-axis direction in which the vehicle travels, and a second acceleration sensor element for detecting an acceleration of the vehicle in a Y-axis direction that is perpendicular to the X-axis direction, said electronic control device being configured to control the behavior of the vehicle based on signals from said first and second acceleration sensor elements:

said method comprising;

mounting said sensor assembly on the vehicle;

keeping the vehicle in a stationary state with the X-axis and Y-axis directions horizontal;

feeding a signal indicating that the vehicle is horizontal to said electronic control unit;

calculating first and second deviation angles of sensing directions of said first and second sensor elements about said X-axis direction in a YZ plane that is perpendicular to said X-axis direction and about said Y-axis direction in an XZ plane that is perpendicular to said Y-axis direction based on outputs from said first and second sensor elements, respectively; and

correcting outputs of said first and second sensor elements while the vehicle is traveling based on said first and second deviation angles.

2. The method of claim 1 further comprising detecting a third deviation angle of each of said first and second sensor elements about a Z-axis direction that is perpendicular to both said X-axis and Y-axis directions in an XY plane that is perpendicular to said Z-axis direction, based on said first and second deviation angles, outputs of said first and second sensor elements while the vehicle is traveling in said X-axis direction on a horizontal surface, and one of an acceleration of the vehicle in said Y-axis direction and an acceleration of the vehicle in said X-axis direction as calculated based on signals from wheel speed sensors mounted on the vehicle, while the vehicle is traveling in said X-axis direction on a horizontal surface;

wherein the outputs of said first and second sensor elements while the vehicle is traveling are corrected based on said first, second and third deviation angles.

3. The method of claim 2 further comprising mounting said vehicle behavior sensor assembly on a substrate such that the sensing directions of said first and second sensor elements are parallel to a surface of said substrate, positioning said substrate such that said surface is perpendicular to a vertical line, detecting outputs of said first and second sensor elements as zero errors inherent to said first and second sensor elements, and mounting said substrate on the vehicle, wherein the outputs of said first and second sensor elements while the vehicle is traveling are corrected based on said first, second and third deviation angles, and said zero errors.

4. The method of claim 2 further comprising mounting said vehicle behavior sensor assembly on a substrate such that the sensing directions of said first and second sensor elements are parallel to a surface of said substrate, positioning said substrate such that the sensing direction of each of said first and second sensor elements is parallel to a vertical line, detecting the output of each of said first and second sensor elements as gain errors inherent to said respective first and second sensor elements, and mounting said substrate on the vehicle, wherein the outputs of said first and second sensor elements while the vehicle is traveling are corrected based on said first, second and third deviation angles, and said gain errors.

8. A vehicle control device comprising a hydraulic unit comprising a housing and control valves for pressure increase and pressure reduction mounted in said housing, an electronic control unit as claimed in claim of claim 1, said electronic control unit being coupled to said hydraulic unit to control said control valves, and a vehicle behavior sensor assembly as claimed in claim 1, said vehicle behavior sensor assembly being mounted in said electronic control unit, wherein the outputs of said first and second acceleration sensor elements are corrected by the method of claim 1.

9. The vehicle control device of claim 8 wherein said vehicle behavior sensor assembly is mounted on a substrate which is mounted on a control substrate disposed in a casing of said electronic control unit for controlling said control valves so as to be upright relative to said control substrate.

5. A method for correcting outputs of a vehicle behavior sensor assembly of a vehicle control device including an electronic control unit, said vehicle behavior sensor assembly comprising a first acceleration sensor element for detecting an acceleration of a vehicle on which said vehicle control device is mounted in an X-axis direction in which the vehicle travels, a second acceleration sensor element for detecting an acceleration of the vehicle in a Y-axis direction that is perpendicular to the X-axis direction, and a third acceleration sensor element for detecting an acceleration of the vehicle in a Z-axis direction that is perpendicular to both said X-axis and Y-axis directions, said electronic control device being configured to control the behavior of the vehicle based on signals from said first, second and third acceleration sensor elements:

said method comprising;

mounting said sensor assembly on the vehicle;

keeping the vehicle in a stationary state with the X-axis and Y-axis directions horizontal and the Z-axis directions parallel to a vertical line;

feeding a signal indicating that the vehicle is horizontal to said electronic control unit;

calculating first, second and third deviation angles of sensing directions of said first, second and third sensor elements about said X-axis direction in a YZ plane that is perpendicular to said X-axis direction, about said Y-axis direction in an XZ plane that is perpendicular to said Y-axis direction, and about said Z-axis direction in an XY plane that is perpendicular to said Z-axis direction, respectively; and

correcting outputs of said first, second and third sensor elements while the vehicle is traveling based on said first, second and third deviation angles.

6. The method of claim 5 further comprising mounting said vehicle behavior sensor assembly on a substrate such that the sensing directions of said first and second sensor elements are parallel to a surface of said substrate, positioning said substrate such that said surface is perpendicular to a vertical line, detecting outputs of said first, second and third sensor elements as zero errors inherent to said first, second and third sensor elements, respectively, and mounting said substrate on the vehicle, wherein the outputs of said first, second and third sensor elements while the vehicle is traveling are corrected based on said first, second and third deviation angles, and said zero errors.

7. The method of claim 5 further comprising mounting said vehicle behavior sensor assembly on a substrate such that the sensing directions of said first and second sensor elements are parallel to a surface of said substrate, positioning said substrate such that the sensing direction of each of said first, second and third sensor elements is parallel to a vertical line, detecting the output of each of said first, second and third sensor elements as gain errors inherent to said respective first, second and third sensor elements, and mounting said substrate on the vehicle, wherein the outputs of said first and second sensor elements while the vehicle is traveling are corrected based on said first, second and third deviation angles, and said gain errors.