6 ms·

Cars are risk adverse for a reason: people's lives are at stake.

by bmitc 3y ago

verdverm 3y ago
steel is stronger than aluminum, in theory that should improve outcomes, all other variables held Tesla vehicles also have some of the highest safety ratings around. Metal choice is also probably less of a factor than the shape of the pieces, so if they can do it with aluminum, steel is probably not that much different edit... It seems most vehicles are primarily made of iron and steel. So do these points made still hold up? Is your vehicle chassis made of aluminum or steel... the answer might surprise the commenters here https://www.statista.com/statistics/882580/us-and-canadian-built-vehicles-average-metal-content-weight-by-type/ https://www.statista.com/statistics/882580/us-and-canadian-b...
- solardev 3y ago
  Unless you're on the other side of it
  - verdverm 3y ago
    metal choice is such a small factor for crash outcomes... what if the other side is a semi truck?
    - raziel2701 3y ago
      Citation on that statement? Materials matter a lot.
      - verdverm 3y ago
        Speed(ing) seems to be the most determinate factor in crashes, which makes sense since it's half of the formula https://www.demandthelimits.com/what-is-the-biggest-factor-involved-in-fatal-automobile-accidents/ https://www.demandthelimits.com/what-is-the-biggest-factor-i... https://www.khanacademy.org/science/physics/linear-momentum/momentum-tutorial/v/introduction-to-momentum https://www.khanacademy.org/science/physics/linear-momentum/... Also consider that existing vehicles are mostly steel today, this is just the body, which can be thinned out, as it does not serve as a major structural component
- Dobbs 3y ago
  Sure the car will come out less damaged, but the pedestrians will be far more likely to die.
  - verdverm 3y ago
    Do you really think if a vehicle hits a pedestrian, that metal choice will make a difference? Wouldn't speed be a more important factor? There are aluminum vehicles that weigh more, it's really momentum rather than gross weight
    - falcolas 3y ago
      Body panel angles and speed are the big ones. Or, to put it another way, can a soft body deform around the vehicle and be thrown away from the impact? The sharp wedge shape from the front grille to the hood kinda says "No" to me. Regardless, it will be good to see what comes out of testing.
    - orwin 3y ago
      It's angle. But we'll see, European crash test are a lot less permissive than the US ones, as regulator don't think 'killing people in older cars, on bike or on foot is a feature!'. If it isn't sold in the EU, it isn't safe. Once again today i'll be fair to Elon, most new US SUV/pickups don't pass EU crash tests.
- polynomial 3y ago
  Pretty sure we have more sophisticated materials science now, so we don't simply have to use such a heavy metal; better to use a lightweight alloy, with the usual crumble zones and strength from design integrity, not basic material strength.
- bmitc 3y ago
  Manufacturers learned decades ago that aluminum is safer for driving, more efficient, and easier to manufacture.
  - yreg 3y ago
    You say it like it's dumb to explore new designs because apparently we've already known for decades everything there is to know.
    - falcolas 3y ago
      Stainless steel has been around longer than cars. I'd say it's fairly safe to assume that some R&D department has done exactly that. Their criteria was probably slightly different than Tesla's, but reduced costs (pennies matter when building things at scale) and increased safety (fewer fines, recalls, etc) are going to be the same.
      - yreg 3y ago
        The manufacturing process and design was entirely different though.
        falcolas 3y ago
        > design was entirely different Frankly, I have doubts. Being entirely different from the rest of the players in this multi-billion dollar industry is a pretty high bar to cross. Especially when some of them have been working in this industry (and had access to the same materials) for over a century.
        verdverm 3y ago
        Yet Tesla has tried different things and now we see the larger auto industry singing a new tune. The most visible example of this is the GigaCast. The Old Auto companies never thought this was a viable path until Tesla showed how superior it actually is. https://www.youtube.com/watch?v=WNWYk4DdT_E https://www.youtube.com/watch?v=WNWYk4DdT_E Sandy Munro is a leading expert in the auto industry, tears down all the vehicles and consults with all the major manufactures. He has many great videos on the trends. One thing he consistently points out is how adverse "old auto" is to new ideas or change of any kind, that they don't know how to innovate
- tgv 3y ago
  Not if you plough your 10(?) tonnes vehicle into another one.
- SteveNuts 3y ago
  That's not really how crumple zones and modern automotive safety works. There are videos of old cars vs. new in crash safety tests. The old cars are "stronger" and hold their shape better, but that doesn't help the occupants at all. It only transfers more energy into the humans inside.
  - verdverm 3y ago
    what prevents similar crumple zones with steel? You don't think we can apply the lessons learned from the last 50 years to a steel body vehicle today? It's not like the strength needs to be consistent everywhere. For example, you might want stronger frame around the battery while still having a crumple zone. Again, I don't see the metal choice as a determinate factor here, you can always make a steel part that underperforms an aluminum one, vice versa too
    - notaustinpowers 3y ago
      Straight steel is tough AF, it doesn't crumple the way modern vehicle metal alloys do. Teslas do have those titanium frames that protect the major areas of the vehicle (passengers and battery mainly), but the rest of the car can be crushed to smithereens and you'd most likely survive. Some parts of cars are steel, which is fine. But having the entire body of the vehicle be steel is where you lose any benefit. What's going to crumple when there are no crumple zones? Most likely your spine...
      - verdverm 3y ago
        > What's going to crumple when there are no crumple zones? So you posit that it is impossible to make crumple zones with steel? That we cannot design a steel part that has crumple features? (or in Tesla's case, a single cast rather than numerous parts bolted or welded together)
        notaustinpowers 3y ago
        Mild steel is used in crumple zones. Stainless steel (like the Cybertruck) is not. Mild steel is much more malleable and provides a much better crumpling. As well as a whole lotta engineering behind the scenes to optimize the type of crumpling. Since stainless steel has chromium in it, it's much tougher when impacted. Which is great for being bulletproof, but is absolutely not the best choice when it comes to prioritizing passenger safety. EDIT: this isn't me being some contrarian cuz I don't like Elon. This is thousands of scientists' discoveries, research, and data over the course of almost 100 years at the tops of their fields in material sciences. If stainless steel could make a good metal to ensure passenger safety, we'd be using it by now.
- bumby 3y ago
  >Tesla vehicles also have some of the highest safety ratings around. According to the IIHS, the Model Y is the only Tesla that made the safest cars list out of nearly 50 vehicles.[1] [1] https://www.consumerreports.org/cars/car-safety/the-safest-new-cars-of-2023-according-to-iihs-a8504542560/ https://www.consumerreports.org/cars/car-safety/the-safest-n...
- jacquesm 3y ago
  Strength in vehicles has to do with directing force more than with deflecting it and for that to work you need to allow for deformation. A 'stronger' body by your definition may well be better at deflecting impact but it ends up being unsafe because a larger amount of the energy involved in the collision gets passed on to the interior of the car. Aluminum or steel isn't the question, the question is how does the chassis deform under various loads and impacts and what compromises do you have to make while engineering such a solution to achieve an acceptable outcome. The materials are different enough that you'd take a completely different approach for each, but you could still end up with a functional equivalent, and when all is said and done I'd expect the Aluminum version to be more expensive, a little bit lighter and harder (or even impossible) to repair after a collision.

Cars are risk adverse for a reason: people's lives are at stake.

by bmitc 3y ago

Cars are risk adverse for a reason: people's lives are at stake.

steel is stronger than aluminum, in theory that should improve outcomes, all other variables held Tesla vehicles also have some of the highest safety ratings around. Metal choice is also probably less of a factor than the shape of the pieces, so if they can do it with aluminum, steel is probably not that much different edit... It seems most vehicles are primarily made of iron and steel. So do these points made still hold up? Is your vehicle chassis made of aluminum or steel... the answer might surprise the commenters here https://www.statista.com/statistics/882580/us-and-canadian-built-vehicles-average-metal-content-weight-by-type/ https://www.statista.com/statistics/882580/us-and-canadian-b...

solardev 3y ago
Unless you're on the other side of it
- verdverm 3y ago
  metal choice is such a small factor for crash outcomes... what if the other side is a semi truck?
  - raziel2701 3y ago
    Citation on that statement? Materials matter a lot.
    - verdverm 3y ago
      Speed(ing) seems to be the most determinate factor in crashes, which makes sense since it's half of the formula https://www.demandthelimits.com/what-is-the-biggest-factor-involved-in-fatal-automobile-accidents/ https://www.demandthelimits.com/what-is-the-biggest-factor-i... https://www.khanacademy.org/science/physics/linear-momentum/momentum-tutorial/v/introduction-to-momentum https://www.khanacademy.org/science/physics/linear-momentum/... Also consider that existing vehicles are mostly steel today, this is just the body, which can be thinned out, as it does not serve as a major structural component
Dobbs 3y ago
Sure the car will come out less damaged, but the pedestrians will be far more likely to die.
- verdverm 3y ago
  Do you really think if a vehicle hits a pedestrian, that metal choice will make a difference? Wouldn't speed be a more important factor? There are aluminum vehicles that weigh more, it's really momentum rather than gross weight
  - falcolas 3y ago
    Body panel angles and speed are the big ones. Or, to put it another way, can a soft body deform around the vehicle and be thrown away from the impact? The sharp wedge shape from the front grille to the hood kinda says "No" to me. Regardless, it will be good to see what comes out of testing.
  - orwin 3y ago
    It's angle. But we'll see, European crash test are a lot less permissive than the US ones, as regulator don't think 'killing people in older cars, on bike or on foot is a feature!'. If it isn't sold in the EU, it isn't safe. Once again today i'll be fair to Elon, most new US SUV/pickups don't pass EU crash tests.
polynomial 3y ago
Pretty sure we have more sophisticated materials science now, so we don't simply have to use such a heavy metal; better to use a lightweight alloy, with the usual crumble zones and strength from design integrity, not basic material strength.
bmitc 3y ago
Manufacturers learned decades ago that aluminum is safer for driving, more efficient, and easier to manufacture.
- yreg 3y ago
  You say it like it's dumb to explore new designs because apparently we've already known for decades everything there is to know.
  - falcolas 3y ago
    Stainless steel has been around longer than cars. I'd say it's fairly safe to assume that some R&D department has done exactly that. Their criteria was probably slightly different than Tesla's, but reduced costs (pennies matter when building things at scale) and increased safety (fewer fines, recalls, etc) are going to be the same.
    - yreg 3y ago
      The manufacturing process and design was entirely different though.
      - falcolas 3y ago
        > design was entirely different Frankly, I have doubts. Being entirely different from the rest of the players in this multi-billion dollar industry is a pretty high bar to cross. Especially when some of them have been working in this industry (and had access to the same materials) for over a century.
        verdverm 3y ago
        Yet Tesla has tried different things and now we see the larger auto industry singing a new tune. The most visible example of this is the GigaCast. The Old Auto companies never thought this was a viable path until Tesla showed how superior it actually is. https://www.youtube.com/watch?v=WNWYk4DdT_E https://www.youtube.com/watch?v=WNWYk4DdT_E Sandy Munro is a leading expert in the auto industry, tears down all the vehicles and consults with all the major manufactures. He has many great videos on the trends. One thing he consistently points out is how adverse "old auto" is to new ideas or change of any kind, that they don't know how to innovate
tgv 3y ago
Not if you plough your 10(?) tonnes vehicle into another one.
SteveNuts 3y ago
That's not really how crumple zones and modern automotive safety works. There are videos of old cars vs. new in crash safety tests. The old cars are "stronger" and hold their shape better, but that doesn't help the occupants at all. It only transfers more energy into the humans inside.
- verdverm 3y ago
  what prevents similar crumple zones with steel? You don't think we can apply the lessons learned from the last 50 years to a steel body vehicle today? It's not like the strength needs to be consistent everywhere. For example, you might want stronger frame around the battery while still having a crumple zone. Again, I don't see the metal choice as a determinate factor here, you can always make a steel part that underperforms an aluminum one, vice versa too
  - notaustinpowers 3y ago
    Straight steel is tough AF, it doesn't crumple the way modern vehicle metal alloys do. Teslas do have those titanium frames that protect the major areas of the vehicle (passengers and battery mainly), but the rest of the car can be crushed to smithereens and you'd most likely survive. Some parts of cars are steel, which is fine. But having the entire body of the vehicle be steel is where you lose any benefit. What's going to crumple when there are no crumple zones? Most likely your spine...
    - verdverm 3y ago
      > What's going to crumple when there are no crumple zones? So you posit that it is impossible to make crumple zones with steel? That we cannot design a steel part that has crumple features? (or in Tesla's case, a single cast rather than numerous parts bolted or welded together)
      - notaustinpowers 3y ago
        Mild steel is used in crumple zones. Stainless steel (like the Cybertruck) is not. Mild steel is much more malleable and provides a much better crumpling. As well as a whole lotta engineering behind the scenes to optimize the type of crumpling. Since stainless steel has chromium in it, it's much tougher when impacted. Which is great for being bulletproof, but is absolutely not the best choice when it comes to prioritizing passenger safety. EDIT: this isn't me being some contrarian cuz I don't like Elon. This is thousands of scientists' discoveries, research, and data over the course of almost 100 years at the tops of their fields in material sciences. If stainless steel could make a good metal to ensure passenger safety, we'd be using it by now.
bumby 3y ago
>Tesla vehicles also have some of the highest safety ratings around. According to the IIHS, the Model Y is the only Tesla that made the safest cars list out of nearly 50 vehicles.[1] [1] https://www.consumerreports.org/cars/car-safety/the-safest-new-cars-of-2023-according-to-iihs-a8504542560/ https://www.consumerreports.org/cars/car-safety/the-safest-n...
jacquesm 3y ago
Strength in vehicles has to do with directing force more than with deflecting it and for that to work you need to allow for deformation. A 'stronger' body by your definition may well be better at deflecting impact but it ends up being unsafe because a larger amount of the energy involved in the collision gets passed on to the interior of the car. Aluminum or steel isn't the question, the question is how does the chassis deform under various loads and impacts and what compromises do you have to make while engineering such a solution to achieve an acceptable outcome. The materials are different enough that you'd take a completely different approach for each, but you could still end up with a functional equivalent, and when all is said and done I'd expect the Aluminum version to be more expensive, a little bit lighter and harder (or even impossible) to repair after a collision.