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Tesla Model S achieves best safety rating of any car ever tested

teslamotors.com

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Re: Tesla Model S achieves best safety rating of any car ever tested

#21

Post by beachstartup »

jlgreco wrote: post #10
turing wrote: post #8

"Of note, during validation of Model S roof crush protection at an independent commercial facility, the testing machine failed at just above 4 g's. While the exact number is uncertain due to Model S breaking the testing machine, what this means is that at least four additional fully loaded Model S vehicles could be placed on top of an owner's car without the roof caving in." I don't have any frame of reference for ho…

I wonder what sort of a drop 4g's translates too. It seems to me that the height you can drop it before the roof caves in is the more important figure, but I guess it is probably more difficult to accurately run the test that way.

i'm guessing that in accidents, cars very rarely drop on their tops - they either roll and come to rest upside-down, or get hit when they're already turned over/sideways.

Re: Tesla Model S achieves best safety rating of any car ever tested

#22

Post by RomP »

This is simply unkind to the competition (and to the poles alike): "Tesla achieved this outcome by nesting multiple deep aluminum extrusions in the side rail of the car that absorb the impact energy (a similar approach was used by the Apollo Lunar Lander) and transfer load to the rest of the vehicle. This causes the pole to be either sheared off or to stop the car before the pole hits an occupant."

There's winning and there's crushing the opponents. One shouldn't gloat in the latter case, but this case deserves an exception.

Congratulations Elon and the team on tremendously nice engineering!

Re: Tesla Model S achieves best safety rating of any car ever tested

#23

Post by jczhang »

baddox wrote: post #12
knowaveragejoe wrote: post #4

> The Model S lithium-ion battery did not catch fire at any time before, during or after the NHTSA testing. It is worth mentioning that no production Tesla lithium-ion battery has ever caught fire in the Model S or Roadster, despite several high speed impacts. While this is statistically unlikely to remain the case long term, Tesla is unaware of any Model S or Roadster occupant fatalities in any car ever. I can't hel…

I wasn't sure exactly what was meant there. At first, I thought it meant that it was statistically unlikely for there to be no battery fires in the long term, but I think it's just referring to occupant fatalities.

I believe it refers to fatalities as this almost exact quote has been said by Elon before in a recent Q&A session.

Re: Tesla Model S achieves best safety rating of any car ever tested

#24

Post by adwf »

marvin wrote: post #5
unionjack22 wrote: post #3

"It is possible to game the regulatory testing score to some degree by strengthening a car at the exact locations used by the regulatory testing machines. After verifying through internal testing that the Model S would achieve a NHTSA 5-star rating, Tesla then analyzed the Model S to determine the weakest points in the car and retested at those locations until the car achieved 5 stars no matter how the test equipment…

So, does anyone want to give odds that Tesla will be a disruptive force in the automotive industry throughout the next decade?

Yeah, I remember beign told at the end of the 90's that if you'd bought 100 shares (~$2000) of Microsoft stock at IPO and sold in '99, you'd have cashed in well over a million dollars.

Tesla gives me that kind of feeling at the moment.

It probably won't be to the same extent as Tesla's market cap is already quite high. So I can't see them splitting quite as much as MS. But on the other hand, I think they're definitely a stock to hold on to for quite a while and see what happens.

Re: Tesla Model S achieves best safety rating of any car ever tested

#26

Post by a-priori »

jlgreco wrote: post #10
turing wrote: post #8

"Of note, during validation of Model S roof crush protection at an independent commercial facility, the testing machine failed at just above 4 g's. While the exact number is uncertain due to Model S breaking the testing machine, what this means is that at least four additional fully loaded Model S vehicles could be placed on top of an owner's car without the roof caving in." I don't have any frame of reference for ho…

I wonder what sort of a drop 4g's translates too. It seems to me that the height you can drop it before the roof caves in is the more important figure, but I guess it is probably more difficult to accurately run the test that way.

Let's see if I remember my high school physics. Making all sorts of assumptions and simplifications here:

F = mv / dt (equation of impulse for zero final velocity)

F = mg (newton's laws)

mg = mv/dt

g = v/dt

9.8 = v/0.5

v = 4.9

Therefore, the car can be travelling no more than 4.9m/s at impact to survive.

mgh = 0.5mv^2 (initial gravitational potential energy = kinetic energy at impact)

gh = 0.5v^2

h = (0.5v^2) / g

h = (0.5 * 4.9 * 4.9) / 9.8

h = 1.225

So, assuming that it takes 0.5 seconds (a wild ass guess) for the car to go from freefall to rest, the car can withstand a drop of 1.2 metres without deforming the roof.

Mind you,

Re: Tesla Model S achieves best safety rating of any car ever tested

#27

Post by tlb »

iandanforth wrote: post #7

Favorite quote: "[T]he exact number is uncertain due to Model S breaking the testing machine"

They picked a wimpy machine if it broke at 4x. Here's one that can apply 159 tons of force (about 80x the weight of a Tesla).

http://www.overbuilt.com/products/car-crushers

Re: Tesla Model S achieves best safety rating of any car ever tested

#29

Post by Florin_Andrei »

RomP wrote: post #22

This is simply unkind to the competition (and to the poles alike): "Tesla achieved this outcome by nesting multiple deep aluminum extrusions in the side rail of the car that absorb the impact energy (a similar approach was used by the Apollo Lunar Lander) and transfer load to the rest of the vehicle. This causes the pole to be either sheared off or to stop the car before the pole hits an occupant." There's winning an…

> There's winning and there's crushing the opponents.

Crushing the opponents while your car remains uncrushed in the test (or the least crushed).

That's what you get when you ask the rocket scientist to make you a car.

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