Restraint deployment control with central and frontal crash sensing

• US 6,198,387 B1
• Filed: 09/24/1999
• Issued: 03/06/2001
• Est. Priority Date: 11/09/1998
• Status: Expired due to Fees

• Current Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Dalum, Joseph Thomas, Wessels, Gerhard F.
• Primary Examiner(s): TONG, NINA C
• Application Number:
  US09/404,176
• Time in Patent Office: 529 Days
• Field of Search: 340/436, 340/903, 340/435, 340/901, 340/904, 307/10.1, 701/45, 280/735, 180/282, 180/273
• US Class Current: 340/436
• CPC Class Codes: B60R 2021/01006 Mounting of electrical components in vehicles
• 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 21/01336 using filtering

Abstract

An improved restraint deployment control with central and frontal acceleration sensing, where the deployment is initiated when a filtered version of the central acceleration signal exceeds a deployment threshold that is periodically adjusted based on secondary measures of crash severity, the secondary measures being determined at least from the frontal acceleration signal. The threshold adjustment also takes into account the progression level of the crash event, as judged by the filtered version of the central acceleration signal. In a preferred implementation, the deployment threshold is set to a relatively high default level during periods of inactivity to provide good immunity to rough road impacts, while providing timely deployment for high speed crash events, and is periodically adjusted from the default level in the course of a sensed event. Preferably, the level of event progression is determined by deriving a ΔV signal from the central acceleration sensor, and comparing such signal to a set of predefined event progression thresholds. At each level or stage of the event progression, the deployment threshold is adjusted within predefined boundaries based on central and frontal crash severity indications. Threshold adjustments based on the central and frontal severity indications are individually limited and then accumulated to determine the net threshold adjustment. In a particularly advantageous embodiment, the secondary measurements include an offset measure based on the difference between two frontal ΔV signals, and corner crush measures based on differences between the frontal and central ΔV signals.

Claims

1. A deployment control for a vehicular supplemental restraint, including a central sensor disposed in a central vehicle location providing a central acceleration signal, at least one remote sensor disposed in a peripheral vehicle location providing a peripheral acceleration signal, and a controller for deploying the restraint in a crash event based on said central and peripheral acceleration signals, the improvement wherein the controller:

initializes a deployment threshold at a default level prior to the crash event;

determines an event progression signal during the crash event based on the central acceleration signal;

determines at least one secondary measure of crash severity during the crash event based on the peripheral acceleration signal;

determines a threshold adjustment amount based on the determined secondary measure and the event progression signal;

periodically adjusts the deployment threshold in accordance with the threshold adjustment amount; and

deploys the restraint when a measure of crash severity based on the central acceleration signal exceeds the deployment threshold.

2. The improvement of claim 1, wherein the controller limits the threshold adjustment amount to a predetermined limit value prior to adjusting the deployment threshold.

3. The improvement of claim 1, wherein the at least one secondary measure of crash severity is a crush measure determined by filtering said central and peripheral acceleration signals to form first and second Δ

velocity signals, and calculating a difference between said first and second Δ

velocity signals.

4. The improvement of claim 3, wherein the at least one remote sensor is a frontal acceleration sensor disposed in a frontal vehicle location.

5. The improvement of claim 1, wherein the deployment control includes first and second remote sensors providing first and second peripheral acceleration signals and the at least one secondary measure of crash severity is an offset measure determined by filtering said first and second peripheral acceleration signals to form first and second Δ

velocity signals, and calculating a difference between said first and second Δ

velocity signals.

6. The improvement of claim 5, wherein the first and second remote sensors are frontal acceleration sensors disposed in left and right frontal vehicle locations.

7. The improvement of claim 1, wherein there are a plurality of secondary measures of crash severity, and the controller:

sums threshold adjustment amounts for each of the plurality of secondary measures to form a net threshold adjustment amount;

limits the net threshold adjustment amount to a predefined limit value; and

adjusts the deployment threshold in accordance with the limited net threshold adjustment amount.

8. A control method for a vehicular supplemental restraint having a central sensor disposed in a central vehicle location providing a central acceleration signal, at least one remote sensor disposed in a peripheral vehicle location providing a peripheral acceleration signal, and a controller for deploying the restraint in a crash event based on said central and peripheral acceleration signals, the method comprising the steps of:

initializing a deployment threshold at a default level prior to the crash event;

determining an event progression signal during the crash event based on the central acceleration signal;

determining at least one secondary measure of crash severity during the crash event based on the peripheral acceleration signal;

determining a threshold adjustment amount based on the determined secondary measure and the event progression signal;

periodically adjusting the deployment threshold in accordance with the threshold adjustment amount; and

deploying the restraint when a measure of crash severity based on the central acceleration signal exceeds the deployment threshold.

9. The control method of claim 8, including the step of:

limiting the threshold adjustment amount to a predetermined limit value prior to adjusting the deployment threshold.

10. The control method of claim 8, wherein the at least one secondary measure of crash severity is a crush measure determined by filtering said central and peripheral acceleration signals to form first and second Δ

velocity signals, and calculating a difference between said first and second Δ

velocity signals.

11. The control method of claim 10, wherein the at least one remote sensor is a frontal acceleration sensor disposed in a frontal vehicle location.

12. The control method of claim 8, including first and second remote sensors providing first and second peripheral acceleration signals, wherein the at least one secondary measure of crash severity is an offset measure determined by filtering said first and second peripheral acceleration signals to form first and second Δ

velocity signals, and calculating a difference between said first and second Δ

velocity signals.

13. The control method of claim 12, wherein the first and second remote sensors are frontal acceleration sensors disposed in left and right frontal vehicle locations.

14. The control method of claim 8, wherein there are a plurality of secondary measures of crash severity, and the control method includes the steps of:

summing threshold adjustment amounts for each of the plurality of secondary measures to form a net threshold adjustment amount;

limiting the net threshold adjustment amount to a predefined limit value; and

adjusting the deployment threshold in accordance with the limited net threshold adjustment amount.