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This is specifically for S3 "Express One Zone"

The speed at which airbags deploy is mind blowing. In the video, the steering wheel air bag starts deploying around 20 ms after impact.

https://www.youtube.com/watch?v=iRKAR0IZlgE


> around 20 ms after impact.

that's the standard for all airbags

https://www.iihs.org/topics/airbags


Why? 20 ms is a very long time in the world of digital electronics. 1 MHz = 1 microsecond ticks, and most embedded MCUs run 10x to 100x faster than that. Sensors and ADCs commonly have microsecond-range response times, too.

The mechanical part (rapid inflation) is more interesting, but for a long time, they did it the "obvious" way: a precisely-calibrated explosive charge, just enough to fill the bag without tearing it apart. Now, I think they're moving toward compressed air, which probably requires some clever engineering to build a sufficiently responsive electronically-controlled valve.


20ms isn't all that long a window over which to filter all that sensor data and determine that you are actually in a crash (and didn't just take a speed bump a little too fast).

False-positive airbag deployments are not viewed very positively by the affected user (even if its strictly better than a single false negative)


A false positive is essentially a false negative (the airbag cannot inflate twice), plus the consequences of knocking the drivers hands off the steering wheel, obscuring their sight and causing a shock that will in most cases cause an accident.

So a false positive seems strictly worse than a false negative to me.


Yes, I guess at speed that is likely the case. It's more the 5-mile-an-hour fender-bender that tends annoy the user when it harmlessly/needlessly deploys the airbags

It's like you answered your own question.

The parent described it as "mind-blowing"; I was curious about that.

Maybe they meant it literally, if your head's in the wrong place.

During these situations, a prompt message can be very reassuring for users, for example:

"We're investigating an issue affecting $X".

As a user, I can rule out that the issue is at my end. I can focus on other things and I won't add to the stack of emails.

This is one of my biggest frustrations with AWS being slow to update their status page during interruptions. I can spend much of the intervening time frantically debugging my software, only to discover the issue is at their end.


I recently came across NanoBaiter on YouTube. He baits scammers and hacks their systems, often disrupting their entire operation.

He identifies the culprits in detail, scares the hell out of them, reports them to police, and tries to inform / refund the victims. In at least one video, he accesses the scammer's Stripe account and refunds the victims (often elderly) for their payments on bogus IT security products. I recall another video where gains access to the CCTV in the scammer's office building, and captures a police raid on the scammers.

https://www.youtube.com/@NanoBaiter


Whilst the benefits of AI are real, the public's expectations exceed reality.

In other words, a bubble occurs when expectations >> reality.


Fantastic explanation, thank you.

For a more detailed description of the Milky Way's rotation curve, this is a brief segment from David Butler's How Far Away Is It video series (which I highly recommend):

https://youtu.be/uVxrsJ5lZlQ?si=ZwpBDpAvTV8AALke&t=1890


Agree, a successful mission needn't be a perfect mission


Any mission you land and can walk from is a successful mission.


Forget the blackjack


See the Auroral oval map https://www.spaceweatherlive.com/en.html

Right now it's appearing over North East US, and should become increasingly visible after sunset.


The lower EV total CO2 footprint is based on current grid CO2 emissions (page 13):

> We use U.S. average electricity grid emissions to estimate manufacturing emissions, while the average electricity grid emissions intensity during vehicle operation are based on a sales-weighted average of where EVs are being sold today.

If the grid is supplied by a growing proportion of renewables + lower CO2 sources over time, the lifetime CO2 footprint of EVs should decline further.


EVs with an efficiency of 150Wh/km charged from a grid that only pollutes at 100g/kWh (eg Brazil, Canada) have a footprint as small as 15g/km.

The US grid is 4x dirtier than that but 60g/km still doesn’t come close to 180g-200g/km of an ICE doing 8l-9l/100km (25-30 mpg.)


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