Method for rollover detection for automotive vehicles with safety-related devices

• US 6,618,656 B2
• Filed: 05/22/2001
• Issued: 09/09/2003
• Est. Priority Date: 05/22/2000
• Status: Expired due to Fees

• Current Assignee: Temic Telefunken Microelectronic GmbH (Continental AG)
• Original Assignee: Temic Telefunken Microelectronic GmbH (Continental AG)
• Inventors: Steiner, Peter, Steurer, Helmut, Kueblbeck, Hermann, Rottenkolber, Ernst, Weidel, Peter
• Primary Examiner(s): Beaulieu, Yonel
• Application Number:
  US09/863,554
• Publication Number:
  US 20030023359A1
• Time in Patent Office: 840 Days
• Field of Search: 701/45, 701/46, 701/47, 701/36, 280/728.1, 280/734, 280/735, 180/282, 180/271, 340/436, 340/438, 340/440
• US Class Current: 701/45
• CPC Class Codes: B60G 2800/9124 Roll-over protection systems, e.g. for warning or control
• CPC Class Codes: B60R 2021/0018 Roll-over
• CPC Class Codes: B60R 2021/01306 monitoring vehicle inclination
• CPC Class Codes: B60R 2021/01325 Vertical acceleration
• CPC Class Codes: B60R 2021/01327 Angular velocity or angular acceleration
• CPC Class Codes: B60R 21/013 including means for detecting collisions, impending collisions or roll-over
• CPC Class Codes: B60R 21/0132 responsive to vehicle motion parameters , e.g. to vehicle longitudinal or transversal deceleration or speed value

Abstract

A method for rollover detection for automotive vehicles with safety-related devices, such as roll bars, (side) airbags and seat-belt tensioners involves the following steps and features. An angular rate of rotation (ω_x) around the vehicle longitudinal axis is provided by the signal of a gyrosensor, and an initial position angle (α₀) identifying the initial position of the vehicle transverse axis is determined from at least one sensor signal. An integral of the angular rate is added to the initial position angle. The absolute value of the resulting sum, which is proportional to the momentary inclination angle relative to the horizontal plane, is then compared to a trigger threshold that is a function of the angular rate and vehicle-specific parameters. A safety-related device is triggered if the absolute value of the resulting sum exceeds the trigger threshold.

Claims

1. Process for rollover detection for automotive vehicles with safety-related devices wherein, by means of an angular rate signal (ω

_x) generated by a gyrosensor (1) in respect of a rotation around the longitudinal axis (X-axis) of the vehicle and by means of an initial position signal (α

₀) generated by a sensor (2) stating the initial position of the transverse axis of the vehicle, the following process steps are performed;

a) calculation of the current inclination angle (α

_curr,calc) according to

2. Process according to claim 1 wherein, as well as the detection of the angle of rotation (ω

_x) and the initial position (α

₀) of the vehicle, additional dynamic motion variables (a_y, a_z, α

_incl) of the vehicle are detected and the following additional process steps are performed;

e) evaluation of the values of the additional dynamic motion variables (a_y, a_z, α

_incl) for self-consistency,

f) determination of the current inclination angle (α

_curr) from the dynamic motion variables (a_y, a_z, α

_incl) if the dynamic motion variables (a_y, a_z, α

_incl) are evaluated as self-consistent,

f1) resetting the calculated current inclination angle (α

_curr,calc) to the value of this current inclination angle (α

_curr),

f2) resetting the integral ∫

ω

_x dt to the value zero, and

f3) then calculating the current inclination angle (α

_curr,calc) according to;

3. Process according to claim 2 wherein the value zero or the value of the last of the inclination angles determined from the dynamic motion variables (a_y, a_z, α

_incl) which was evaluated as self-consistent is used as the assessed value (α

_ass).

4. Process according to claim 3 wherein the calculated current inclination angle (α

_curr,calc) is returned in stages to the assessed value (α

_ass) in successive time segments.

5. Process according to claim 4 wherein at least the vertical acceleration (a_z) and lateral acceleration (a_y) detected by acceleration sensors (3) and the inclination angle of the vehicle detected by an inclination sensor (2) are used as dynamic motion variables (a_y, a_z, α

_incl).

6. Process according to claim 5 wherein the signal of the inclination sensor (2) is defined as the value of the current inclination angle (α

_curr) in accordance with process step f).

7. Process according to claim 3 wherein the calculated current inclination angle, (α

_curr,calc) is continuously returned to the assessed value (α

_ass) during a defined time segment.

8. Process according to claim 7 wherein at least the vertical acceleration (a_z) and lateral acceleration (a_y) detected by acceleration sensors (3) and the inclination angle of the vehicle detected by an inclination sensor (2) are used as dynamic motion variables (a_y, a_z, α

_incl).

9. Process according to claim 8 wherein the signal of the inclination sensor (2) is defined as the value of the current inclination angle (α

_curr) in accordance with process step f).

10. Process according to claim 2 wherein at least the vertical acceleration (a_z) and lateral acceleration (a_y) detected by acceleration sensors (3) and the inclination angle of the vehicle detected by an inclination sensor (2) are used as dynamic motion variables (a_y, a_z, α

_incl).

11. Process according to claim 10 wherein the signal of the inclination sensor (2) is defined as the value of the current inclination angle (α

_curr) in accordance with process step f).

12. A process for rollover detection in a motor vehicle equipped with a safety-related device, comprising the steps:

a) providing an angular rate of rotation of the vehicle about a longitudinal axis of the vehicle, from a signal generated by a first gyrosensor;

b) providing an initial position angle defining an initial angular position of a transverse axis of the vehicle, from at least one signal generated by at least one second sensor;

c) calculating a current inclination angle as a sum of the initial position angle and a time integral of the angular rate;

d) providing a trigger threshold as a predetermined static tipping angle of the vehicle minus a product of a constant and the absolute value of the angular rate, wherein the constant is a settable vehicle-specific constant that is also a function of at least one of a vehicle condition of the vehicle and a crash sequence which the vehicle is undergoing;

e) comparing the absolute value of the current inclination angle with the trigger threshold; and

f) if the absolute value of the current inclination angle exceeds the trigger threshold, then generating a trigger signal that is indicative of the detection of a rollover condition of the vehicle and that is adapted to trigger the safety-related device.