GlueckAuf
Well-Known Member
At every rocket launch we attend, there are perhaps hundreds of energetics present on or near the range that are fired by solid state triggers. And many of us place our mugs less than a meter in front of them for hours at a time, in a fully-armed state, while en route to the range. They're known as Supplemental Restraint Systems. Airbags. They're present in every new car since 1998, but were pioneered in the mid-80s in a few models, like my own 1987 Mercedes 560 SL.
When airbags were first introduced into production automobiles, their firing sensors were exclusively mechanical. For example, a steel ball in a tube oriented with the car's axis, with a magnet on the aft end and an electrical switch on the opposite end. Other similar sensors used a weight and spring. Either type was designed to roll or extend forward if sufficient deceleration force acted on it to close an electrical firing switch, igniting a gas-generating squib, and inflating the airbag.
Why mechanical sensors? My suspicion is that engineers and risk analysis experts wanted a familiar, trusted, envision-able means to effect the potentially-hazardous inflation of those early airbag systems. (Sound familiar?)
There was at that time in the mid 80s a general distrust and discomfort growing in the public with the ever-more-present, mysterious, sealed electronic "black boxes" under the hoods of new cars, replacing many familiar mechanical systems that had been in use for decades.
The angst reached a fever pitch in 1986 with a 60 Minutes piece that "exposed" the propensity of the Audi 5000 to suddenly accelerate so powerfully that no driver could brake hard enough to stop it. And it was pure BS, another case of journalistic malpractice.
Today though, thankfully, airbags are no longer triggered by those 1980s-era mechanical collision sensors, but by sophisticated, exhaustively-tested, and billions-of-hours proven solid state sensors. These feature multi-axial collision sensing, allowing multiple airbags to be smartly inflated--or not--depending on the severity and type of collision sensed.
Now those Takata anti-personnel fragmentation airbags? That's another story.
When airbags were first introduced into production automobiles, their firing sensors were exclusively mechanical. For example, a steel ball in a tube oriented with the car's axis, with a magnet on the aft end and an electrical switch on the opposite end. Other similar sensors used a weight and spring. Either type was designed to roll or extend forward if sufficient deceleration force acted on it to close an electrical firing switch, igniting a gas-generating squib, and inflating the airbag.
Why mechanical sensors? My suspicion is that engineers and risk analysis experts wanted a familiar, trusted, envision-able means to effect the potentially-hazardous inflation of those early airbag systems. (Sound familiar?)
There was at that time in the mid 80s a general distrust and discomfort growing in the public with the ever-more-present, mysterious, sealed electronic "black boxes" under the hoods of new cars, replacing many familiar mechanical systems that had been in use for decades.
The angst reached a fever pitch in 1986 with a 60 Minutes piece that "exposed" the propensity of the Audi 5000 to suddenly accelerate so powerfully that no driver could brake hard enough to stop it. And it was pure BS, another case of journalistic malpractice.
Today though, thankfully, airbags are no longer triggered by those 1980s-era mechanical collision sensors, but by sophisticated, exhaustively-tested, and billions-of-hours proven solid state sensors. These feature multi-axial collision sensing, allowing multiple airbags to be smartly inflated--or not--depending on the severity and type of collision sensed.
Now those Takata anti-personnel fragmentation airbags? That's another story.
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