Variable time venting algorithm

• US 6,929,283 B2
• Filed: 06/07/2004
• Issued: 08/16/2005
• Est. Priority Date: 10/31/2002
• Status: Expired due to Fees

• Current Assignee: Key Safety Systems, Inc. (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: Key Safety Systems, Inc. (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Gioutsos, Tony, Tabar, Daniel
• Primary Examiner(s): English, Peter C.
• Application Number:
  US10/862,143
• Publication Number:
  US 20040232673A1
• Time in Patent Office: 435 Days
• Field of Search: 280/735, 280/736, 280/739, 280/743.2, 701/45, 701/46, 701/47
• US Class Current: 280/735
• CPC Class Codes: B60R 2021/01218 control of expansion speed
• CPC Class Codes: B60R 21/01504 detecting bag displacement

Abstract

An algorithm for evaluating information from sensors interacting with strips that are extended during activation of the airbag determines whether the airbag has contacted an out-of-position occupant. In one embodiment, each strip includes an alternating pattern that generates a frequency in a sensor through which the strip passes during deployment. The frequency generated is based upon the speed with which the strip passes by the sensor and, in turn, the speed of deployment of the airbag. A controller evaluates the frequency and the changes in frequency from the sensor during deployment. Depending upon the specific configuration of the system and the specific vehicle, a decrease in the speed of deployment of the airbag may be indicated by a decrease in the frequency of the signal. A decrease in speed of deployment may indicate that the airbag is in contact with an occupant

Claims

1. A computer readable medium storing a computer program which when executed by a computer performs the steps of:

a. analyzing a speed of deployment of an airbag;

b. determining whether the airbag has contacted an out-of-position occupant;

c. controlling the airbag to cease or continue inflation based upon the determination in step b;

d. receiving a signal indicative of the speed of deployment of the airbag; and

e. analyzing frequency components of the signal in order to perform the determination in step b; and

f. performing a frequency domain transform in order to analyze the frequency components of the signal in said step e.

2. The computer readable medium of claim 1 wherein the frequency domain transform is a Walsh transform.