Airbag system collision history recording method

• US 6,915,195 B2
• Filed: 02/21/2003
• Issued: 07/05/2005
• Est. Priority Date: 03/11/2002
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Miyoshi, Kentaro
• Primary Examiner(s): Chin, Gary
• Application Number:
  US10/369,516
• Publication Number:
  US 20030168839A1
• Time in Patent Office: 865 Days
• Field of Search: 701 45- 47, 701/29, 701/35, 340/438, 340/439, 280/735, 180/282
• US Class Current: 701/45
• CPC Class Codes: B60R 21/0132 responsive to vehicle motion parameters , e.g. to vehicle longitudinal or transversal deceleration or speed value
• CPC Class Codes: B60R 21/0173 Diagnostic or recording means therefor

Abstract

Acceleration data on acceleration that a vehicle undergoes are written in a readable memory, the acceleration being detected by an acceleration sensor. When an airbag is inflated, the time of the inflation is determined. Either acceleration data on acceleration that the vehicle undergoes during a predetermined time period before or after the determined time or acceleration data on acceleration that the vehicle undergoes during two predetermined time periods before and after the determined time are read from the readable memory, and the acceleration data read from the memory are stored in a nonvolatile memory as a collision history.

Claims

1. An airbag system collision history recording method, comprising

inflating an airbag based on acceleration data indicating that a vehicle is in a collision;

writing the acceleration data in a readable memory;

determining an inflation time when said airbag is inflated;

reading a first portion of the acceleration data corresponding to a first predetermined time period before said inflation time; and

storing the first portion of the acceleration data in a nonvolatile memory, in a reverse chronological order starting from the inflation time, as a collision history.

2. The method according to claim 1, wherein the first predetermined time period extends from a collision start time to said inflation time.

3. The method according to claim 1, further comprising:

reading a second portion of the acceleration data corresponding to a second predetermined time period after said inflation time; and

storing the second portion of the acceleration data in a nonvolatile memory, in a chronological order starting from the inflation time, as a second part of the collision history.

4. The method according to claim 3, wherein the first portion of the acceleration data is stored in the nonvolatile memory before the second portion of the acceleration data.

5. The method according to claim 3, wherein the first predetermined time period extends from a collision start time to said inflation time, and the second predetermined time period extends from said inflation time to a collision end time.

6. The method according to claim 1, further comprising:

reading a second portion of the acceleration data corresponding to a second predetermined time period after said inflation time;

reading a third portion of the acceleration data corresponding to a third predetermined time period before said first predetermined time period;

reading a fourth portion of the acceleration data corresponding to a fourth predetermined time period after said second predetermined time period;

storing the second portion of the acceleration data in a nonvolatile memory, in a chronological order starting from the inflation time, as a second part of the collision history;

storing the third portion of the acceleration data in the nonvolatile memory, in a reverse chronological order starting from an end point of the first portion, as a third part of the collision history; and

storing the fourth portion of the acceleration data in the nonvolatile memory, in a chronological order starting from an end point of the second portion, as a fourth part of the collision history.

7. The method according to claim 6, wherein:

the first portion of the acceleration data is stored in the nonvolatile memory before the second portion of the acceleration data;

the second portion of the acceleration data is stored in the nonvolatile memory before the third portion of the acceleration data; and

the third portion of the acceleration data is stored in the nonvolatile memory before the fourth portion of the acceleration data.

8. The method according to claim 6, wherein the first predetermined time period extends from a collision start time to said inflation time, the second predetermined time period extends from said inflation time to a collision end time;

the third predetermined time period extends from said collision start time to a data recording start time, and the fourth predetermined time period extends from said collision end time to a second collision end time.

9. The method according to claim 1, further comprising:

reading a second portion of the acceleration data corresponding to a second predetermined time period after said inflation time; and

storing the second portion of the acceleration data in a nonvolatile memory, in a reverse chronological order starting from a collision end time, as a second part of the collision history.

10. The method according to claim 9, wherein the first portion of the acceleration data is stored in the nonvolatile memory before the second portion of the acceleration data.

11. The method according to claim 9, wherein the second portion of the acceleration data is stored in the nonvolatile memory before the first portion of the acceleration data.

12. The method according to claim 9, wherein the first predetermined time period extends from a collision start time to said inflation time, and the second predetermined time period extends from said inflation time to a collision end time.