Rivian Rollover

[GlockandRoll]

I'll re-phrase:

The physics of the handling dynamics of a Cybertruck will be vastly different from those of a gas powered 4x4 due to the dramatically lower center of gravity that is also more centralized. Yes, I consider roll-over dynamics part of handling characteristics.

It's surprising that you're pushing back on these simple concepts. I thought everyone knew about the roll-over advantages conferred by having a lower center of gravity and no heavy engine up high under the hood.

We aren't talking about a gas-powered truck, we are talking about a Rivian, that has a much lower center of gravity. In fact, I'm willing to bet due to the sheer size and weight of the cold-rolled 30x stainless steel exoskeleton, that the Rivian might even have a lower center of gravity.

Trucks flip over in fleids all the time by trying to turn while traveling at enough of a rate of speed that the front tire digs into a rut and it's like a pole-vault for the rear end with centripetal forces wanting to bring the rear end up and over while turning.

It happens a lot more than you might realize.

And since you mention it - I'm surprised you can't understand simple physics.

Sponsored

 

[Crissa]

We aren't talking about a gas-powered truck, we are talking about a Rivian, that has a much lower center of gravity. In fact, I'm willing to bet due to the sheer size and weight of the cold-rolled 30x stainless steel exoskeleton, that the Rivian might even have a lower center of gravity.

Trucks flip over in fleids all the time by trying to turn while traveling at enough of a rate of speed that the front tire digs into a rut and it's like a pole-vault for the rear end with centripetal forces wanting to bring the rear end up and over while turning.

It happens a lot more than you might realize.

And since you mention it - I'm surprised you can't understand simple physics.

Very unlikely for the Rivian, which does not have active height control, and a more narrow stance, to have a lower center of gravity than the Cybertruck.

The exoskeleton is not really very dense above the door line.

-Crissa

 

[Ogre]

The exoskeleton is not really very dense above the door line.

Depends on who’s driving.

 

[Crissa]

Depends on who’s driving.

Well, that wouldn't be exo, then, would it? Or really, skeleton, either, in relation to the truck.

-Crissa

 

[SwampNut]

Depends on who’s driving.

 

[HaulingAss]

We aren't talking about a gas-powered truck, we are talking about a Rivian, that has a much lower center of gravity. In fact, I'm willing to bet due to the sheer size and weight of the cold-rolled 30x stainless steel exoskeleton, that the Rivian might even have a lower center of gravity.

Trucks flip over in fleids all the time by trying to turn while traveling at enough of a rate of speed that the front tire digs into a rut and it's like a pole-vault for the rear end with centripetal forces wanting to bring the rear end up and over while turning.

It happens a lot more than you might realize.

And since you mention it - I'm surprised you can't understand simple physics.

Please try to follow the conversation. Yes, the comparison made by a previous poster and also by you is that 4x4 trucks flip over all the time. The comparison both of you are making is to gas/diesel trucks. Because while electric trucks can be flipped, they do not flip nearly as easily as gas/diesel trucks. Because physics.

Note that I never said physics make it impossible to flip an EV, just that it's not nearly as easy. I didn't need the initial post to prove to me it was possible for an EV to flip, and I agree the Cybertruck will be harder to flip than the Rivian. That said, I could probably flip either of them fairly easily if I tried to. It's not that difficult if you know what you are doing. And people who flip them in a soft, level field obviously don't know what they are doing (assuming the flip was not purposeful). The steering wheel can prevent this kind of flip so those who flip simply brodying around a soft field are using the wrong steering inputs. You need to turn the wheels in the direction of the impending flip, and you need to be quick about it. The driver also probably had it in the high ground clearance mode which would be a foolish mistake for that kind of driving.

The R1T can be adjusted from between 7.9 and 14.4 inches and the highest mode is not for brodying because it uses up the rebound of the suspension dampers and makes the suspension more susceptible to a hard top out which can contribute greatly to the energy pitching the truck over. I'm guessing Rivian will program the speed of the truck to be limited in the highest suspension setting to reduce the chances of this kind of roll-over in the future. It won't eliminate it, it will simply make it less likely.

 

[GlockandRoll]

Please try to follow the conversation. Yes, the comparison made by a previous poster and also by you is that 4x4 trucks flip over all the time. The comparison both of you are making is to gas/diesel trucks. Because while electric trucks can be flipped, they do not flip nearly as easily as gas/diesel trucks. Because physics.

Note that I never said physics make it impossible to flip an EV, just that it's not nearly as easy. I didn't need the initial post to prove to me it was possible for an EV to flip, and I agree the Cybertruck will be harder to flip than the Rivian. That said, I could probably flip either of them fairly easily if I tried to. It's not that difficult if you know what you are doing. And people who flip them in a soft, level field obviously don't know what they are doing (assuming the flip was not purposeful). The steering wheel can prevent this kind of flip so those who flip simply brodying around a soft field are using the wrong steering inputs. You need to turn the wheels in the direction of the impending flip, and you need to be quick about it. The driver also probably had it in the high ground clearance mode which would be a foolish mistake for that kind of driving.

The R1T can be adjusted from between 7.9 and 14.4 inches and the highest mode is not for brodying because it uses up the rebound of the suspension dampers and makes the suspension more susceptible to a hard top out which can contribute greatly to the energy pitching the truck over. I'm guessing Rivian will program the speed of the truck to be limited in the highest suspension setting to reduce the chances of this kind of roll-over in the future. It won't eliminate it, it will simply make it less likely.

Turning in the direction of a skid doesn't do that much if they are stuck in a rut, because there is no skid, you just flip over... maybe you don't understand that, tired of explaining it.

And name your wager if you want to bet that a CT has a lower CoG than the R1T lol.

 

[Crissa]

Turning in the direction of a skid doesn't do that much if they are stuck in a rut, because there is no skid, you just flip over... maybe you don't understand that, tired of explaining it.

And name your wager if you want to bet that a CT has a lower CoG than the R1T lol.

Alas, turning the wheels into a skin will help when in a rut. Because your big tires are suddenly more capable of rolling out of the rut.

Ruts are bad, yeah, because they give you inconsistent but strong angular grip. But that doesn't mean there's not a way out of it. That also doesn't mean there was a way out, either, given prior inputs.

That why prior inputs - such as wearing the seatbelt - are so important.

-Crissa

 

[HaulingAss]

Turning in the direction of a skid doesn't do that much if they are stuck in a rut, because there is no skid, you just flip over... maybe you don't understand that, tired of explaining it.

And name your wager if you want to bet that a CT has a lower CoG than the R1T lol.

You turn your wheels in the direction of the potential flip mostly to manage momentum in a sideways slide and also so your tires don't get caught in the rut. The Rivian comes with 34" tires which is a large enough diameter to roll through most ruts. Of course, the field the Rivian rolled in was just a soft grassy field so it's pretty obvious the steering and throttle was improperly managed. A flip in a field like this was likely a combination of mismanagement of the throttle in combination with steering inputs, especially with regen braking kicking in when letting off the throttle. It was user error anyway you look at it. Saying it's "really easy to do" is simply ignoring that the driver's skill is a determining factor. It's really easy to drive a truck into a brick wall too but not many do it because they know it's not going to end well. You don't need to school me, I was four-wheeling before you even had a learner's permit!

As to center of gravity:

The R1T has a relatively short vehicle length. That's going to impact the center of gravity negatively because it requires packaging more weight up high. It will also depend upon which ride height assumptions you use since both the Cybertruck and the R1T have adjustable suspensions. Other factors include the range (battery size) of each truck, and wheel size. So you would have to decide upon exactly which two versions are being compared.

Unfortunately, auto manufacturers do not publish center of gravity figures, not even for one specific configuration and ride height.

 

[Ogre]

If you want to maximize your center of gravity, there are ways to do it.

I see a disturbing number of trucks like this around here. Often towing a big trailer as well.

 

[FutureBoy]

I think Tesla is closest to having a vehicle that truly thinks for itself. But it does not do that 100% at this moment. Ai is able to use informative inputs to make predictive decisions. But it is not aware of what it is doing.

We are talking about a Rivian mind you.

The truck did not decide to do anything.

Edit: The more I ponder this, the more I see that the word think and decisions are blending together in my brain. While I still do not agree with the statement that the Rivian "decided to roll over". I do see how Tesla's and a few other auto makers have vehicles that can make decisions. But i highly doubt any of those decisions would be to roll over.

Unless the owner was training it to imitate a dog playing roll over and play dead. If the suspension works right it could even shake, but probably not beg.

 

[Crissa]

Of course, coulda been a gopher or badger living in that field and your tire break through their tunnel and suddenly your rut is a ditch,

-Crissa

 

[charliemagpie]

To me, even though the driver said he didn't do anything that bad, it was bad enough to roll over.

So, he did do something that bad.

If he is high off the ground, and his driving style is as if he is low to the ground, he should at least feel the need to turn on the brain.

Look Ma, No Hands !!!!

 

[Ogre]

Worth noting: the photos show the truck on it’s side in a nice flat, mowed field. There are no tracks in that field. No slide marks, this is where the truck landed after rolling 20+ feet (driver side, roof, passenger side).

While we’ve been talking about gopher holes, it’s entirely possible there is a small hill off camera which caused the entire issue.

 

[GlockandRoll]

You turn your wheels in the direction of the potential flip mostly to manage momentum in a sideways slide and also so your tires don't get caught in the rut. The Rivian comes with 34" tires which is a large enough diameter to roll through most ruts. Of course, the field the Rivian rolled in was just a soft grassy field so it's pretty obvious the steering and throttle was improperly managed. A flip in a field like this was likely a combination of mismanagement of the throttle in combination with steering inputs, especially with regen braking kicking in when letting off the throttle. It was user error anyway you look at it. Saying it's "really easy to do" is simply ignoring that the driver's skill is a determining factor. It's really easy to drive a truck into a brick wall too but not many do it because they know it's not going to end well. You don't need to school me, I was four-wheeling before you even had a learner's permit!

As to center of gravity:

The long range R1T has a relatively short vehicle length. That's going to impact the center of gravity negatively because it requires packaging more weight up high. It will also depend upon which ride height assumptions you use since both the Cybertruck and the R1T have adjustable suspensions. Other factors include the range (battery size) of each truck, and wheel size. So you would have to decide upon exactly which two versions are being compared.

Unfortunately, auto manufacturers do not publish center of gravity figures, not even for one specific configuration and ride height.

if it's in a rut, it digs in, the direction the wheel is turned doesn't do much... it's when the front end of the car is MOVING when the direction the wheel is turned matters. But, I digress, as you can't seem to grasp this, nor do you understand that the CT will have a higher CoG as the "body" as it where (in this case the Exoskeleton) is much, much much heavier than the R1T which can rely on more of the skateboard concept.

As far as you playing the "I"m a man and you are a boy" card, I've been offroading since the early 70's, had my 1st motorcycle at 76, and my 1st ATV in 80. I am also a pilot and an engineer and do not need to waste any more time in engaging in a battle of wits with an unarmed man.

You are now ignored.

Sponsored