Vehicle restraint device control method and apparatus using dynamically determined threshold

• US 20060025912A1
• Filed: 07/27/2004
• Published: 02/02/2006
• Est. Priority Date: 07/27/2004
• Status: Active Grant

• Current Assignee: Robert Bosch Corporation (Robert Bosch GmbH), Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Haering, Juergen, Stuetzler, Frank-Juergen
• Granted Patent: US 7,477,974 B2
• Time in Patent Office: Days
• 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 21/01336 using filtering

Abstract

A method of controlling a restraint device in a vehicle, and an apparatus employing the method. The method includes sensing accelerations of the vehicle, determining an energy value, determining a transformed acceleration, retrieving a threshold based on the transformed acceleration, and activating the restraint device when the energy value is above the threshold.

Claims

1. A method of controlling a restraint device in a vehicle, the method comprising:

sensing an amount of acceleration of the vehicle;

determining from the amount of acceleration an energy value indicative of the energy dissipated in the vehicle;

determining from the amount of acceleration a transformed acceleration;

retrieving a threshold based on the transformed acceleration; and

generating an activation signal when the energy value is above the threshold.

2. The method of claim 1, wherein determining the transformed acceleration value further comprises:

determining an absolute value of the acceleration amount; and

mapping the absolute value of the acceleration amount.

3. The method of claim 1, wherein determining the transformed acceleration value further comprises at least one of quantizing the acceleration amount, and low pass filtering the acceleration amount.

4. The method of claim 1, further comprising high-pass filtering the acceleration amount.

5. The method of claim 1, wherein determining the energy value comprises:

determining a second absolute value of a second acceleration amount; and

summing the absolute values of the first and the second acceleration amounts.

6. The method of claim 1, wherein determining the energy value comprises determining an energy envelope of the acceleration amount.

7. The method of claim 1, further comprising disabling the restraint device when the determined energy value for the transformed acceleration is below the retrieved threshold.

8. The method of claim 1, further comprising activating the restraint device with the activating signal.

9. A method of controlling a restraint device in a vehicle, the method comprising:

sensing a vehicle condition and creating a first signal indicative of the acceleration of the vehicle;

determining a second signal from the first signal indicative of the acceleration;

retrieving a threshold based on the first signal indicative of the acceleration and the second signal;

comparing the second signal with the threshold; and

generating a deployment signal based on the comparison.

10. The method of claim 9, further comprising activating the restraint device when the value of the second signal is above the threshold.

11. The method of claim 9, further comprising high-pass filtering the sensed first signal indicative of the acceleration.

12. The method of claim 9, wherein determining the second signal further comprises:

determining an absolute value of the first signal; and

mapping the absolute value of the first signal.

13. The method of claim 9, wherein determining the second signal further comprises at least one of quantizing the acceleration amount, and low pass filtering the acceleration amount.

14. The method of claim 9, further comprising generating a disabling signal to the restraint device when a value of the second signal is below the threshold.

15. The method of claim 9, further comprising generating an enabling signal to the restraint device when a value of the second signal is above the threshold.

16. The method of claim 9, further comprising:

sensing a second amount of acceleration;

determining an absolute value of the first signal;

determining an absolute value of the second amount of acceleration; and

summing the absolute values of the first signal and the second amount of acceleration.

17. The method of claim 9, wherein determining the first signal comprises determining an energy envelope of the first signal.

18. The method of claim 9, wherein determining the first signal comprises determining an energy of the first signal.

19. An apparatus for controlling a restraint device in a vehicle, the apparatus comprising:

a sensor configured to sense a plurality of vehicle conditions having values indicative of vehicle accelerations;

an accumulator configured to accumulate the values indicative of the vehicle accelerations to obtain an accumulated value;

a transformer configured to transform the accumulated value into a transformed value; and

a signal generator configured to activate the restraint device when the accumulated value exceeds a threshold determined from the transformed value.

20. The apparatus of claim 19, further comprising a memory capable of storing the threshold.

21. The apparatus of claim 19, wherein the signal generator disables the restraint device when the accumulated value is below the threshold determined from the transformed value.

22. The apparatus of claim 19, further comprising a high-pass filter configured to filter the sensed values.

23. The apparatus of claim 19, further comprising an absolute-value module configured to determine an absolute value for each of the sensed values.

24. The apparatus of claim 23, wherein the transformer further comprises at least one of a mapping module coupled to the absolute-value module and configured to map the absolute value for each of the sensed values.

25. The apparatus of claim 19, wherein the transformer further comprises at least one of a low-pass filter coupled to the absolute-value module and configured to low-pass filter the absolute value for each of the sensed values, and a quantizer coupled to the absolute-value module and configured to quantize the absolute value for each of the sensed values, to obtain the transformed value.

26. The apparatus of claim 19, wherein the signal generator comprises a comparator configured to compare the accumulated value and the threshold determined from the transformed value.

27. The apparatus of claim 19, wherein the sensor comprises an accelerometer.

28. The apparatus of claim 19, further comprising a processor coupled to the sensor, and configured to receive the values and to retrieve the threshold.

29. A method of controlling a restraint device in a vehicle, the method comprising:

sensing at least one amount of acceleration of the vehicle;

determining from the amount of acceleration a transformed acceleration;

determining a velocity value from the transformed acceleration by integrating the transformed acceleration;

retrieving a threshold based on the velocity value;

determining from the acceleration amount an energy value indicative of the energy dissipated in the vehicle;

activating the restraint device when the energy value is above the threshold.

30. A method of controlling a restraint device in a vehicle, the method comprising:

sensing an amount of acceleration of the vehicle;

determining a velocity value from the amount of acceleration;

retrieving a dynamic threshold based on the velocity value;

determining from the amount of acceleration an energy value indicative of the energy dissipated in the vehicle; and

generating an activation signal when the energy value is above the threshold.

31. An apparatus for controlling a restraint device in a vehicle, the apparatus comprising:

a processor configured to receive a sensed amount of acceleration of the vehicle;

determine a velocity value from the amount of acceleration;

retrieve a threshold based on the velocity value;

determine from the amount of acceleration an energy value indicative of the energy dissipated in the vehicle; and

generate an activation signal when the energy value is above the threshold.