Method and device for deploying a retaining system

• US 6,487,482 B1
• Filed: 10/04/2000
• Issued: 11/26/2002
• Est. Priority Date: 02/20/1998
• Status: Expired due to Term

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Meissner, Peter, Heckel, Jörg, Mattes, Bernhard, Schaumann, Arno, Henne, Michael
• Primary Examiner(s): Beaulieu, Yonel
• Application Number:
  US09/622,511
• Time in Patent Office: 783 Days
• Field of Search: 307/9.1, 307/10.1, 701/36, 701/45, 280/735, 280/734, 340/435, 340/436, 340/438, 180/271, 180/282
• US Class Current: 701/45
• CPC Class Codes: B60R 2021/0119 Plausibility check
• CPC Class Codes: B60R 21/013 including means for detecting collisions, impending collisions or roll-over
• CPC Class Codes: B60R 21/0133 by integrating the amplitude of the input signal
• CPC Class Codes: B60R 21/0136 responsive to actual contact with an obstacle , e.g. to vehicle deformation, bumper displacement or bumper velocity relative to the vehicle monitoring crash strength in combination with passenger seat detection B60R21/01558

Abstract

A method and a device for deploying a restraint system, which avoids false deployments at the least possible expense by using an acceleration sensor arrangement that includes two sensitivity axes oriented in different directions. An acceleration measured with respect to one of the two sensitivity axes is used for a plausibility check of a deployment decision, which is determined from an acceleration measured with respect to the other sensitivity axis. A trigger signal is only generated if a deployment decision signal and a plausibility signal are present at the inputs of an AND logic circuit at the same time.

Claims

1. A method for deploying a restraint system in response to an impact of a motor vehicle against an obstacle, the motor vehicle including an acceleration sensor arrangement having two sensitivity axes, one arranged in the X-direction, and one in the Y-direction, with the X-direction describing the direction of travel, and the Y direction describing the vehicle transverse direction, the method comprising the steps of:

generating a trigger signal for the restraint system from measured

accelerations using an evaluation circuit;

using a measured acceleration with respect to one of the two sensitivity axes for a plausibility check of a deployment decision;

determining the deployment decision as a function of a measured acceleration with respect to the other of the two sensitivity axes using the evaluation circuit; and

emitting the trigger signal only if a deployment decision signal and a plausibility signal are present simultaneously at inputs of an AND logic circuit.

2. The method according to claim 1, further comprising the step of:

performing a reciprocal plausibility check, wherein;

the acceleration sensor arrangement includes two acceleration sensor elements having different sensitivity axes.

3. The method according to claim 1, wherein:

the acceleration sensor arrangement includes three acceleration sensor elements, two of three acceleration sensor elements having sensitivity axes oriented in one direction, a third of the three acceleration sensor elements having a sensitivity axis oriented in a second direction, the first direction being different from the second direction; and

one of the two acceleration sensor elements having sensitivity axes oriented in one direction is used for the plausibility check of the third of the three acceleration sensor elements.

4. The method according to claim 1, wherein:

the two sensitivity axes include a first sensitivity axis oriented in a longitudinal direction and a second sensitivity axis oriented in a transverse direction.

5. The method according to claim 1, wherein:

an acceleration sensor element is arranged centrally in the motor vehicle and has a sensitivity axis in a transverse direction of the motor vehicle;

at least one lateral impact sensor is arranged on a periphery of the motor vehicle; and

the at least one lateral impact sensor uses the acceleration sensor element for the plausibility check.

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

for the plausibility check, performing a threshold decision with respect to one of;

one of an amplitude, a gradient, and a polarity of the measured acceleration, and

one of an amplitude, a gradient, and a polarity of an integral of the measured acceleration.

7. A device for deploying a restraint system in response to an impact of a motor vehicle against an obstacle, comprising:

an acceleration sensor arrangement having two sensitivity axes, one arranged in the X-direction, and one in the Y-direction, with the X-direction describing the direction of travel, and the Y direction describing the vehicle transverse direction;

an evaluation circuit, the evaluation circuit generating a trigger signal for the restraint system as a function of measured accelerations, the evaluation circuit including an arrangement for performing a plausibility check of a deployment decision as a function of a measured acceleration with respect to one of the two sensitivity axes, the evaluation circuit determining the deployment decision as a function of a measured acceleration with respect to the other of the two sensitivity axes; and

an AND logic circuit emitting the trigger signal if a deployment decision signal and a plausibility signal are present at inputs of the AND logic circuit at the same time.