BenzWorld Junior Member
Date registered: Jan 2008
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Acceleration is just change of speed.
Deceleration is the same, where a negative acceleration is a positive deceleration.
The typcial dynamics are (found with some research)
0 sec: Impact
25 msec: electronic signal to deploy airbag
30 msec: airbag starts to inflate
55 msec: airbag fully inflated
85 msec: driver is fully hitting airbag and removing back from airbag
for the passenger, deployment ist initiated appr. 10 msec later, as passenger is farer away from impact area than driver.
From this information it is clear, that the dynamic of inflation of the airbags has to be adjusted to the car and seat position.
The questions here are:
1. Should an airbag deploy fast enough (no matter of speed of impact between say 20 mph to 80 mph) that the passenger and driver touch the airbag before touching the dashboard? I believe, up to 30g deceleration this should be the target. (i.e. if there is more than 30g deceleration you might be dead anyway with or without airbag. However, I have no other information on the design of airbag systems.)
2. Should the integrated belt system bend so much to the front as seen on the pictures? I think not.
3. Was there first, in this crash, a non fatal deceleration (for belted passengers) for which, the crash sensor decided not to deploy airbags first. Which let the passenger hit the dashboard. And was there a second much more heavy impact which led deploy the airbag, unfortunately throwing back passengers head to the roof?
4. In case 3., the airbag might have saved the life of the passenger. If the airbag would have deployed in first phase, it would not been available to be deployed for phase two.
5. All are assumptions. It would be interested to read out the airbag control unit. Is it available?
6. How exactly, in msec, is the design of the airbag deployment dynamics for the car of the accident. It might be interesting to ask Mercedes about that.
Last edited by Dirk124; 09-14-2010 at 07:13 AM.