4 ms·

5% is actually extremely impressive. I do not think there will be a "zero" car with the current understanding of physics and materials (maybe a new super materi

5% is actually extremely impressive. I do not think there will be a "zero" car with the current understanding of physics and materials (maybe a new super material can be developed. A non-newtonian interface would be awesome to see). The amount of kinect energy a car has is absolutely absurd. The energy has to go somewhere and redirecting it away from the occupants is not an easy task.

hvidgaard 8y ago
There is a physical limitation, because of the deceleration tolerated by the human body has an upper limit if you want people to survive.
- dsfyu404ed 8y ago
  Vehicle crashes by themselves are nowhere near the upper limits of the amount of force the human body can survive. With proper harnesses we could survive speeds well in excess of 100mph straight into a wall. The problem is passenger cabins can't survive that. http://www.ejectionsite.com/stapp.htm http://www.ejectionsite.com/stapp.htm The problem is that passenger vehicle restraints suck because they have to fit anybody and everybody and simple enough that you actually use them. In the upper classes of racing it's not uncommon for someone to walk away with only a concussion after a barrel roll down the infield but they have better seats and harnesses. Even a 4pt harness like found in a go-cart or small aircraft would be a massive step up.
  - davidgould 8y ago
    Go-karts do not have harnesses at all, much less four-point harnesses. Source, ex kart racer.
    - dsfyu404ed 8y ago
      Off road go-carts usually have a simple 4pt.
  - hvidgaard 8y ago
    And how does that contradict my claim? There is an upper limit to what the human body can survive, and going into a wall with 160kmph (100mph) and claim we can survive is a dishonest statement at best. If the car has a 4m long deformation zone the force is around 50g for 0.1 second. That is unrealistic, and 1m is probably more realistic, producing 200g for 0.023s. Neither is clearly survivable. I'm not disputing that we can make very safe vehicles, just look at F1 drivers walking away from 300kmph crashes, but they shed so much energy to tires, tire barriers, gravel and all the other stuff that slow them down.
- SmellyGeekBoy 8y ago
  I always liked the "Demolition Man" approach of filling the car with some kind of instantly-solidifying foam. The mental image of Stallone busting his way out always comes to mind when these conversations come up!
  - dpkonofa 8y ago
    I once saw a demo of a foam sealant that could be used temporarily to fill cracks in a basement. The demo had a person shove the end of the can into a crack and then just press it and shot out and filled the crack. Once it absorbed enough water, it would start to dissolve and came out as a kind of slurry where it could easily be vacuumed and replaced with a proper sealant. It wasn't a permanent fix but was just there to buy some time. If they could implement a system like that in a car where the foam fills the cabin instantly and then water or sprinklers quickly dissolve it, something like Demolition Man could probably be a reality.

hvidgaard 8y ago

There is a physical limitation, because of the deceleration tolerated by the human body has an upper limit if you want people to survive.

dsfyu404ed 8y ago
Vehicle crashes by themselves are nowhere near the upper limits of the amount of force the human body can survive. With proper harnesses we could survive speeds well in excess of 100mph straight into a wall. The problem is passenger cabins can't survive that. http://www.ejectionsite.com/stapp.htm http://www.ejectionsite.com/stapp.htm The problem is that passenger vehicle restraints suck because they have to fit anybody and everybody and simple enough that you actually use them. In the upper classes of racing it's not uncommon for someone to walk away with only a concussion after a barrel roll down the infield but they have better seats and harnesses. Even a 4pt harness like found in a go-cart or small aircraft would be a massive step up.
- davidgould 8y ago
  Go-karts do not have harnesses at all, much less four-point harnesses. Source, ex kart racer.
  - dsfyu404ed 8y ago
    Off road go-carts usually have a simple 4pt.
- hvidgaard 8y ago
  And how does that contradict my claim? There is an upper limit to what the human body can survive, and going into a wall with 160kmph (100mph) and claim we can survive is a dishonest statement at best. If the car has a 4m long deformation zone the force is around 50g for 0.1 second. That is unrealistic, and 1m is probably more realistic, producing 200g for 0.023s. Neither is clearly survivable. I'm not disputing that we can make very safe vehicles, just look at F1 drivers walking away from 300kmph crashes, but they shed so much energy to tires, tire barriers, gravel and all the other stuff that slow them down.
SmellyGeekBoy 8y ago
I always liked the "Demolition Man" approach of filling the car with some kind of instantly-solidifying foam. The mental image of Stallone busting his way out always comes to mind when these conversations come up!
- dpkonofa 8y ago
  I once saw a demo of a foam sealant that could be used temporarily to fill cracks in a basement. The demo had a person shove the end of the can into a crack and then just press it and shot out and filled the crack. Once it absorbed enough water, it would start to dissolve and came out as a kind of slurry where it could easily be vacuumed and replaced with a proper sealant. It wasn't a permanent fix but was just there to buy some time. If they could implement a system like that in a car where the foam fills the cabin instantly and then water or sprinklers quickly dissolve it, something like Demolition Man could probably be a reality.