A crumple material that will crumple in a car vs pedestrian collision? Like NERF foam or something?

I recall one manufacturer popped the hood so that it could act as a shock absorber should a pedestrian land on it...

Found it - Nissan has an actuator[0] that lets the cars hood be used as a damper for unlucky pedestrians in case of collision.

[0] https://www.nissan-global.com/EN/INNOVATION/TECHNOLOGY/ARCHI...

It's a far cry from Nerf, with fiberglass on top of it, but styrofoam is actually used inside bumpers

Ahaha I was thinking of passengers. Hence "how do they get eaten?" But even so, were old car shapes really worse than modern car shapes? Seems like you get hit, you're gonna have a bad time no matter what.

There is a reason RR and Mercedes don't sell hood ornaments any more in certain markets as an example. They first crush your legs and then shread everything above. I imagine some of the 50s and 60s designs will be worse with sharp corners and pointy spikes.

Even for people in the car, some older car designs put the drivers legs under the engine block. In a head on collision at speed, the legs were the crumple zone (meanwhile the steering column was being pushed through your torso).

edit: also recently people noticed that high 'trucks' would simply miss the crumple zones in the car they were crashing into

> Another problem is "impact incompatibility" where the "hard points" of the ends of chassis rails of SUVs are higher than the "hard points" of cars, causing the SUV to "override" the engine compartment of the car.[18] In order to tackle this problem, more recent SUV/off-roaders incorporate structures below the front bumper designed to engage lower-height car crumple zones

"Even for people in the car, some older car designs put the drivers legs under the engine block. In a head on collision at speed, the legs were the crumple zone (meanwhile the steering column was being pushed through your torso)."

Anytime anyone waxes nostalgic about how "they dont make cars like they used" I think about this video. They sure as hell don't make cars like they used too, you can get out and walk away from a crash in your ugly newer car that would brutally end your life in one of those beautiful classic cars.

For anyone that is curious the key thing to pay attention to in survivability here (besides yah know... the airbag) is.. does the interior cab of the car change shape? The cab of the old car violently changes shape in a way that would destroy parts of your body whereas the newer car's cab doesnt seem to be affected at all. Even if getting crushed between the seats and dashboard didnt kill you immediately in the bel air, I struggle to imagine how emergency first responders would even get you out of that.

https://youtu.be/C_r5UJrxcck

I agree with you, but crashing a 50-year old car also isn't the same as crashing a new car. Rust, failed fasteners, etc has to bias that crash to make it even worse for the old car.

"Rust, failed fasteners, etc has to bias that crash to make it even worse for the old car."

Did you see that bel air in the video? It is in beautiful condition as far as I can tell.

Besides, things like rust would make the car crumple more not less and the issue is that the car doesnt crumple enough (in the right spots) so I imagine rust in the frontend could actually make it safer ironically.

My understanding: Crumple zones only work in conjunction with hard points behind them. If the engine goes into your knees and the wheel into your chest, they weren't strong enough, or guided in safer directions. Crumple zones' primary job is to make the stop more gradual, to reduce G-forces and whiplash.

> edit: also recently people noticed that high 'trucks' would simply miss the crumple zones in the car they were crashing into

Yup. But because pickup truck drivers still want to sit 50 feet above traffic, the trucks end up with these ridiculously tall front ends and complain about how ridiculous they look. When you tell them it's so you don't run over other cars and kill the occupants in a crash, they literally tell you that they don't care.

This comment actually got a laugh out of me. I truly have no idea what would be feasible in a collision like this. Probably packing peanuts? Airbags on the outside of the car that deploy when a pedestrian is detected?

Pedestrian airbags have been designed before, but don't seem to have caught on widely [1].

A more bizarre solution Google patented always stuck with me: A sticky car hood beneath an eggshell coating so that a struck pedestrian would stay on top of the car instead of falling and hitting their head or being run over [2].

1: https://www.youtube.com/watch?v=CiiBlirAG8w

2: https://www.popularmechanics.com/technology/a20953/google-pa...

There are wearable airbags on the market for motorcycle use. I don't know how effective they are for their intended use or how effective they might be protecting a pedestrian, but it's a technology that exists.

Such airbags would throw a pedestrian away. A long way.

Unfortunately you're being down voted, but the reality is there are crumple zones built into some hoods (bonnets) that help protect the pedestrian from immediately impacting the solid parts of the engine. So the concept isn't completely unexplored.

+ explosive charges that will deform the hood to better catch a pedestrian. I’ve seen one go off when somebody drove into a bollard

Could you point me to the car manufacturer that puts explosive charges in their cars? Asking for a friend... who is myself.

Airbags and seatbelt pre-tensioners have "explosives" in them (they convert very rapidly into gas, but I'm not sure all of them always meet the usual standards of explosives).

The defective Tanaka airbags used ammonium nitrate, of Oklahoma City Bombing and Beirut port fame.

The Mazda MX-5 bonnet system:

https://owners-manual.mazda.com/gen/en/mx-5/mx-5_8fl9ee16j/c...

They wanted to keep the profile of the car low which didn't allow for the space normally needed, so they provide it 'on demand' in case of impact. Unfortunately for a friend of mine who is an owner, that turned a fairly minor collision with an object into a several thousand pound repair as the system shears the bonnet mounts and deforms the bonnet.

This is how airbags work as well, so everyone.

All of them. It's called an airbag.

Seatbelt tensioners too.

Don't all airbags deploy using electronically set-off explosives?

Euro NCAP test suite features vulnerable road user protection tests [0] including for pedestrians and cyclists. The NHTSA might start recommending some limited technological additions for pedestrian protection in the future [1].

[0] https://www.euroncap.com/en/vehicle-safety/the-ratings-expla... [1] https://www.nhtsa.gov/press-releases/five-star-safety-rating...

That's exactly what we do. All that mostly air filled plastic that is used to shape the bulbous front ends of modern front ends on cars and crossovers serves this purpose. If you ever look at a car and wonder why there's so much unused space between the grill and radiator that's why.

Materials that crumple when they impact a soft, squishy human? What?

Edit: yep, @Buttons840 nailed it..

People are already made out of crumple material. Also splat material.