Pre-Safe Sound: Playing ‘pink noise’ in the split second before impact (2015)
This is a comment from Reddit on the same [0]; though I cannot vouch for its veracity, I found it interesting nonetheless:Former Benz master tech here.I've spent a good bit of time diving into the nitty gritty of these systems.It uses all of the vehicle sensors to determine crash logic.You want to fire the pretensioners before the airbags if at all possible. This locks the occupants in a much more secure and predictable psition.Accelerometers can determine if something like a rollover is in progress.Heavy braking + high speed + sudden activation of the parking sensors indicates a crash before physical contact happens.It can use the radar on distronic equipped cars to predict a crash.If the vehicle is in a slide, and a sudden yaw correction happens, this means a collision has occurred, even if the airbag sensors haven't been triggered. This is useful because the airbag sensors are only good at detecting force in one dimension.It's even possible for the vehicle to determine to fire the pretensioners but no airbags based on occupant size and weight (determined through seat/steering wheel position and capacitive mats in the seats) and impact vectors.It will even do things like full field the alternator up to 18+ volts to slam the windows shut super fast in the event of a rollover.The actual detection logic fills a 4" thick book.It's a big reason those cars are so damn expensive.Mercedes doesn't fuck around with safety.If I had to be in a wreck, it would be in an S class. Hands down.0: http://www.reddit.com/r/todayilearned/comments/59qhaw/til_ne...