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Optimal Timing to Trigger an Airbag
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English
Abstract
An airbag upon collision of automobiles must finish expanding at the time when the driver's body arrives at the surface of the expanded airbag from the normal position and it must receive the body softly. Either early or late expansion reduce the effect. Determination of the optimal timing for trigger the airbag is quite important. But it is a difficult job, due to the time delay in the bag filling with the gas after collision.
This paper focuses on the issue of the airbag technology to how to find the optimal trigger timing and presents a new and straightforward algorithm to determine the timing by introducing the concept of the prediction. The algorithm first predicts how the driver's body will move in the future time for a time equivalent to the delay time and triggers the airbag by the predicted information so that it can compensate the delay by the airbag operation.
The algorithm determines the timing only from the acceleration measured by one sensor set in the automobile and is composed of the following four basic processing blocks;
- Kalman filtering to estimate the acceleration of the driver's body and its time derivative from the noisy measured acceleration.
- Filtering to estimate the velocity and displacement of motion of the driver's body.
- Prediction of the velocity and displacement of motion of the driver's body after collision.
- Judgement to trigger the airbag from the above variables estimated and predicted variables.
Simulations in the various conditions were carried out and the results demonstrated the validity of the algorithm.
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Authors
Topic
Citation
Watanabe, K. and Umerawa, Y., "Optimal Timing to Trigger an Airbag," SAE Technical Paper 930242, 1993, https://doi.org/10.4271/930242.Also In
References
- Messer Schmitt Patent Japan-49-55031 1974
- Bosch Patent Japan-63-503531 1988
- Kanto-Seiki Patent Japan-4-146851 1992
- Enouen Susan Guenther Dennis A. Saul Roger A. MacLaughlin Thomas F. “Comparison of Models Simulating Occupant Response with Air Bags” SAE Trans. 343 358 1984
- Brantman Russel Breed David “Use of Computer Simulation in Evaluating Airbag System Performance” SAE Trans. 1072 1081 1985
- Suzuki Naoyuki inoue Shigemitsu Nakahama Ryoji “Determination of Airbag Sensor Threshold Level by Graphic Method” SAE Trans. 307 316 1989
- Bergfried Dietrich E. Mattes Bernhard Rutz Martin “Electronic Crash Sensors for Restraint System” SAE Trans. 1252 1260 1990
- Diller Robert W. “Electronic Sensing of Automobile Carshes of Airbag Deployment” SAE Trans. 65 68 1991