CommodoreAmiga

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The point is the actual cabin intrusion and forces applied to the test dummies are vastly more important than whether any particular part bends. None of this can be reliably derived from the videos.

As an example (XC90):
1613851070863.png


1613851146557.png


Vehicles are designed to function as a system and focusing on a single part may or may not be indicative of the overall results. The Dodge Ram shows no A pillar deformation but has problems with cabin intrusion and forces applied to the test dummies in even the moderate overlap test.

Too soon to draw conclusions about occupant safety until the actual test data is released, but if a non-deforming A pillar is a "must have", you'll likely need to move on to another vehicle.
People on this forum need to take a step back and really re-think their position, in life. I bring up a concern and the entire time I go out of my way to say it’s simply a concern that we need more data on... Yet there are people here who immediately go to an extreme to.

1. Insist that Rivian is perfect (how they arrive at this conclusion without the very data I say I need, I do not know).
2. Insist anyone who says otherwise needs to move on to another vehicle.

Well golly gee, I’m sorry that I care about safety and that has offended you. I’d tell you how I really felt about your opinion, but that would be rude. You can have your opinion, but please just leave me alone with mine.





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srkz

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[...] but also the object you're colliding with is not stationary, but rather is traveling at a high speed towards you (higher energy).
That's not how physics works. A car hitting an immovable brick wall at any given speed has equal force acting on it as if it hit a car of equal mass traveling the opposite direction at equal speed.
 

zmachine

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Well, the F-150 crash test the A pillar doesn't stay perfect but it still has very good safety crash review.
 

carz

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Did anyone else notice that the wheels don't appear to be one piece rims, but appear to have a hubcap for appearance. See attached photo:
vlcsnap-2021-02-19-23h04m03s584.png
It looks like the Rivian doesn't bounce back and instead glides after it crashes in the small overlap test. Volvo does the same in most of its current models, and one common element is that the rims break exactly the same as you see it in that screenshot, to prevent the wheel from getting stuck against the passenger compartment and making the car bounce back.

Overall, with the very limited data that you can extract from such a short video, looks very promising with no red-flags, but I will wait to see the official results before I order one.
 

Lucanjo

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That's not how physics works. A car hitting an immovable brick wall at any given speed has equal force acting on it as if it hit a car of equal mass traveling the opposite direction at equal speed.
True(ish)... The reason that a vehicle hitting an immovable barrier is the same as a vehicle hitting a similar vehicle at equal the speed is because they share the force. They both deform and the crumple zones absorbed equal energy. If the other vehicle or whatever you hit does not absorb the same force as you, that force is going into your vehicle. A car hitting a stationary immutable barrier and a car hitting an immutatbale barrier traveling at the same speed in the opposite direction will be 2x the force.
 

srkz

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True(ish)... The reason that a vehicle hitting an immovable barrier is the same as a vehicle hitting a similar vehicle at equal the speed is because they share the force. They both deform and the crumple zones absorbed equal energy. If the other vehicle or whatever you hit does not absorb the same force as you, that force is going into your vehicle. A car hitting a stationary immutable barrier and a car hitting an immutatbale barrier traveling at the same speed in the opposite direction will be 2x the force.
It's not simply 2x the force, it depends on the mass of the two objects. If a wall of infinite mass hit a car going the same speed it would be infinitely more force than a car vs car (literally.) If a chunk of concrete the same mass as a car hit that car going the same speed, it would be the same force as if the car hit an immutable wall of infinite mass standing still.

Anyway hitting a car that comes over the center divider is not inherently more force than hitting a wall as in the crash test. The front overlap test is equivalent to two cars of similar mass hitting each other head on going the same speed. Same force, not more.
 

Lucanjo

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Ayway hitting a car that comes over the center divider is not inherently more force than hitting a wall as in the crash test. The front overlap test is equivalent to two cars of similar mass hitting each other head on going the same speed. Same force, not more.
Completely agree. Same mass, same speed and same ability to absorb the force, it is equal to hitting the immovable barrier as in the crash test.
 

LeoH

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I am not going to dismiss the concern, because at the end of the day you need to feel comfortable in the car. Personally, I am not concerned as the deformity means force that escaped the crumble zone was absorbed by the A-pillar, and not the passenger. Now, is that by design? I sure hope so, given RJ's background, I highly doubt he would let this go public if it was not by design. Another reason could be that they would rather the A-pillar deform, that having damage happen to the battery or it's housing, so force is directed upwards.

We do not have enough information, but there is no harm is inquiring to be on the same side.
 

DuckTruck

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Damn! I sure love the passion, intelligence, and reasoned arguments this group brings to this forum every day of the week! It's just like watching Congressional hearings on C-SPAN, only different...
 

Whmorken

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The point is the actual cabin intrusion and forces applied to the test dummies are vastly more important than whether any particular part bends. None of this can be reliably derived from the videos.

As an example (XC90):
1613851070863.png


1613851146557.png


Vehicles are designed to function as a system and focusing on a single part may or may not be indicative of the overall results. The Dodge Ram shows no A pillar deformation but has problems with cabin intrusion and forces applied to the test dummies in even the moderate overlap test.

Too soon to draw conclusions about occupant safety until the actual test data is released, but if a non-deforming A pillar is a "must have", you'll likely need to move on to another vehicle.
This is a great discussion. Thanks.
 

skyote

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DuckTruck

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