Method of generating a calibration crash sensor output pulse

• US 6,721,642 B1
• Filed: 02/20/2003
• Issued: 04/13/2004
• Est. Priority Date: 02/20/2003
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Cheng, James Chih, Wu, Chi-Chin
• Primary Examiner(s): Marc-Coleman, Marthe Y.
• Application Number:
  US10/368,899
• Time in Patent Office: 418 Days
• Field of Search: 701/45, 701/47, 703/8, 703/6, 340/438, 244/122.G, 280/735
• US Class Current: 701/45
• CPC Class Codes: B60R 2021/01184 Fault detection or diagnostic circuits in power circuits B60R2021/01129
• CPC Class Codes: B60R 21/013 including means for detecting collisions, impending collisions or roll-over
• CPC Class Codes: B60R 21/0173 Diagnostic or recording means therefor

Abstract

A method of generating a calibration crash sensor pulse using the combination of a generated high frequency band of response (HFB) from a non-destructive impact test and a generated low frequency band (LFB) of response from computer aided engineering analysis.

Claims

1. A method of generating a calibration crash sensor output pulse for air bag system development including the steps of:

predicting a high frequency band of response portion of the crash sensor output pulse;

predicting a low frequency band of response portion of the crash sensor output pulse;

combining the high frequency band pulse and the low frequency band pulse to form a calibration crash output pulse;

using logic analysis on the calibration crash output pulse; and

generating an air bag firing signal only if the step of using logic analysis indicates the occurrence of a vehicle crash requiring activation of the air bag.

2. A method of generating a calibration crash sensor output pulse as recited in claim 1 wherein the step of predicting a high frequency band of response is done from a non-destructive impact test.

3. A method of generating a calibration crash sensor pulse as recited in claim 1 wherein the step of predicting a high frequency band of response is done using a single destructive test.

4. A method of generating a crash sensor crash pulse as recited in claim 1 wherein the step of predicting a low frequency band of response is done using a computer aided engineering analysis including using a lumped mass model to generate lower frequency responses and using finite element analysis to generate lower frequency responses.

5. A method of generating a calibration crash sensor output crash pulse as recited in claim 2 including the steps of using a linear transformation to obtain the high frequency band pulse at high speed from the high frequency band pulse at low speed.

6. A method of generating a calibration crash sensor output crash pulse as recited in claim 5 including generating a high frequency pulse using an integrated momentum ratio, wherein a first elastic wave is multiplied by the ratio of the integrated momentum of a higher speed test to the integrated momentum of a lower speed test, so that the high frequency elastic waves of a higher vehicle speed test can be generated without destructive testing.

7. A method of generating a calibration crash sensor output pulse as recited in claim 5 including generating a high frequency band pulse using a integrated momentum ratio, wherein destructive testing is used and a high frequency band pulse extracted from the destructive test is being used as a basis to generate high frequency band pulse that would occur at any other vehicle speeds.

8. A method of testing an air bag firing system including generating a calibration crash sensor output pulse for air bag system development and applying the calibrations crash sensor output pulse to an air bag firing control module, said method including the steps of:

predicting a high frequency band of response portion of the crash sensor output pulse, by using a nondestructive impact test and, by using a linear transformation to obtain the high frequency band pulse at other crash speeds, including generating a high frequency pulse function using an integrated momentum ratio, wherein a first function representing a first elastic wave is multiplied by the ratio of the integration of momentum of a higher speed test to the integration of momentum of a lower speed test, so that the high frequency elastic waves of a higher vehicle speed test can be generated without destructive testing;

predicting a low frequency band of response portion of the crash sensor output pulse using computer aided engineering analysis including using lumped mass model to generate lower frequency responses;

combining the high frequency band pulse and the low frequency band pulse to form a calibration crash sensor output pulse;

using logic analysis on the calibration crash output pulse to determine if air bag activation is required;

applying the calibration crash output pulse to the air bag firing control module; and

generating an air bag firing signal only if the step of using logic analysis indicates the occurrence of a vehicle crash requiring activation of the air bag.