R1T vs. R1S in snow?

[Dark-Fx]

That's cool and all, but same limitations.

If you can lock up the differential it'll send all the torque to one wheel if the other is spinning, instead of causing it to reduce it by 50%. Gear ratio should stay the same instead of halving the way they are doing brake lock-up now. Of course if the rumoured quad motor enduro comes out, you've now eliminated the possible torque advantage in this situation though.

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[R1Thor]

If you can lock up the differential it'll send all the torque to one wheel if the other is spinning, instead of causing it to reduce it by 50%. Gear ratio should stay the same instead of halving the way they are doing brake lock-up now. Of course if the rumoured quad motor enduro comes out, you've now eliminated the possible torque advantage in this situation though.

That's...literally not how the physics of differentials works.

I put the playlist from Engineering Explained in my post above. He breaks it down much more eloquently than I can, especially via text in a forum...

 

[Nine_One_Six_R1S]

That being said, I have conceded that, depending on how the QM is programmed from a software standpoint, it can absolutely be worse. But it can also absolutely be MUCH better when you can control each wheel discretely and make 100 micro-adjustments per second and control exactly what each wheel is putting to the ground. The best differentials in the world are analog and have zero real-world correction factors. Luckily for us, and the way we've had to develop these to overcome the 'downfalls' of having a single-powerplant ICE vehicle development strategy for the past 100 years, the gearing advantages in differentials tends to allow the distribution of power to where you still have traction. But again, it's limited power, and it's discrete, not intelligent. Even in DCCD cars, that control the differentials electronically, we see power-delivery and slippage limitations.

Source: mechanics and physics.

That Rivian can emulate something close to a differential via software? I've read many arguments that it can't be done.

It does not have to be 100% equivalent just some way to get the same pwr to all 4 wheels.

is that even possible?

 

[R.I.P.]

But bottom line is that this RIP guy doesn't have all of the facts, despite the fact that he thinks he does, and then insists so, annoyingly, and incessantly.

No, I don't think anybody has "all the facts", but what I do have is a lot of actual wheel time in a variety of vehicles, to include the Hummer EV, Rivian R1T Quad, Rivian R1T Enduro and F150 Lightning.

I have shared what I have learned driving the Hummer & the Rivian's here because whereas a lot of guys like to talk theory, not a lot have had and (extensively) driven both the QM and the DM in very challenging terrain.

Hopefully some have found the reports from my experience helpful. I have even had a member of the forum meet me for some machine testing. That invite remains open.

I can, however, see where it might be "annoying" to have your belief system challenged, but what I would suggest is to put the keyboard down, get with your local 4x4 club and prove your theories on the ground. At the end of the day, that is the only place they really matter.

 

[R1Thor]

No, I don't think anybody has "all the facts", but what I do have is a lot of actual wheel time in a variety of vehicles, to include the Hummer EV, Rivian R1T Quad, Rivian R1T Enduro and F150 Lightning.

I have shared what I have learned driving the Hummer & the Rivian's here because whereas a lot of guys like to talk theory, not a lot have had and (extensively) driven both the QM and the DM in very challenging terrain.

Hopefully some have found the reports from my experience helpful. I have even had a member of the forum meet me for some machine testing. That invite remains open.

I can, however, see where it might be "annoying" to have your belief system challenged, but what I would suggest is to put the keyboard down, get with your local 4x4 club and prove your theories on the ground. At the end of the day, that is the only place they really matter.

It's not a 'belief' system.

It's physics.

Science is under no obligation to make sense to you. Anecdote ≠ data.

I have ZERO qualms with being wrong. ZERO. But I've seen ZERO proof from anyone of these claims you're making. They're baseless and sensationalistic!

Keep getting high on your own supply my man. I'd honestly be THRILLED to pat you on the back in person, and buy you a coffee/beer/whatever the MINUTE you show me actual, controlled data. Because the only thing that can disprove science, is newer, better science!!

 

[R1Thor]

That Rivian can emulate something close to a differential via software? I've read many arguments that it can't be done.

It does not have to be 100% equivalent just some way to get the same pwr to all 4 wheels.

is that even possible?

I think it's absolutely possible.

There's nuance to it. Because it's VERILY difficult to overcome slippery friction. You want static friction between your contact patch and the ground. So, being able to intentionally adjust for your rolling friction to achieve (or in the case of slippage, RE-acquire) static friction is incredibly powerful. In *theory* the QM could do this with software control and put EXACTLY the power needed to EXACTLY the right place at EXACTLY the right time.

In practice, the reason R.I.P. seems so credible is because we don't know that that's the case here. I still would love to see a DM go head to head with a QM with professional drivers on a closed course.

Or even better, can we get a set of trucks to these guys??? https://www.youtube.com/channel/UCJfliGgEFUBDyqTuNzGbH4A

 

[R.I.P.]

That's...literally not how the physics of differentials works.

I put the playlist from Engineering Explained in my post above. He breaks it down much more eloquently than I can, especially via text in a forum...

Welp. See. Here is the problem with a lot of the stuff you post. You post a lot of theory, but from some of the stuff you say, there is not a lot of on-the-ground experience behind it.

In fact, Dark FX is correct. A totally locked system (such as my TJ rock crawler) can indeed put 100% of the available torque to a single wheel given that there is zero traction on the other three.

What is confusing you is the fact that when triple locked, there is no longer any "differential" action. It has disappeared, along with the physics associated with it. All that is left is a solid drive line to all 4 wheels.

Again. Put the keyboard away, come out & play with us, learn how this stuff works.

 

[Phatman113]

He claims to have knowledge of an aftermarket locking differential that's coming soon. Hasn't really elaborated at all but I suppose I can't blame him. Probably a significant amount of testing still needed on that kind of a system before you start marketing it.

Oh man, I hope it's that stupid aftermarket product that you clip into your brake lines, and you step on your brakes, flip the switch for whatever wheel you don't want spinning, and then it just holds pressure on those brakes while you release the brake for the other wheels...

 

[R1Thor]

Welp. See. Here is the problem with a lot of the stuff you post. You post a lot of theory, but from some of the stuff you say, there is not a lot of on-the-ground experience behind it.

In fact, Dark FX is correct. A totally locked system (such as my TJ rock crawler) can indeed put 100% of the available torque to a single wheel given that there is zero traction on the other three.

What is confusing you is the fact that when triple locked, there is no longer any "differential" action. It has disappeared, along with the physics associated with it. All that is left is a solid drive line to all 4 wheels.

Again. Put the keyboard away, come out & play with us, learn how this stuff works.

I'd love to.

While your at it, please call Penn State and let their professors know they've failed me miserably and should tear up my Engineering Degree.

And while we're both at it, let's bring Jason Fenske along, because his YouTube Channel would probably clear 20 million views on this one, especially when he whips out his whiteboard and markers.

 

[Phatman113]

I think it's absolutely possible.

There's nuance to it. Because it's VERILY difficult to overcome slippery friction. You want static friction between your contact patch and the ground. So, being able to intentionally adjust for your rolling friction to achieve (or in the case of slippage, RE-acquire) static friction is incredibly powerful. In *theory* the QM could do this with software control and put EXACTLY the power needed to EXACTLY the right place at EXACTLY the right time.

In practice, the reason R.I.P. seems so credible is because we don't know that that's the case here. I still would love to see a DM go head to head with a QM with professional drivers on a closed course.

Or even better, can we get a set of trucks to these guys??? https://www.youtube.com/channel/UCJfliGgEFUBDyqTuNzGbH4A

These guys kinda did that with QM vs Toyota...

 

[Dark-Fx]

That's...literally not how the physics of differentials works.

I put the playlist from Engineering Explained in my post above. He breaks it down much more eloquently than I can, especially via text in a forum...

If it's locked it effectively stops being a differential. Torque is all about gear ratios. Locked differentials have a constant gear ratio.

 

[R.I.P.]

If it's locked it effectively stops being a differential. Torque is all about gear ratios. Locked differentials have a constant gear ratio.

EXACTLY.

 

[R1Thor]

If it's locked it effectively stops being a differential. Torque is all about gear ratios. Locked differentials have a constant gear ratio.

I missed the part where we were talking about locked diffs. I see there was a quick mention of it above, but last I'd checked, this entire thread was regarding snow performance--you don't want locked diffs for snow. Did we switch to rock crawling when I wasn't looking?

 

[Dark-Fx]

I missed the part where we were talking about locked diffs. I see there was a quick mention of it above, but last I'd checked, this entire thread was regarding snow performance--you don't want locked diffs for snow. Did we switch to rock crawling when I wasn't looking?

*shrug*

 

[R.I.P.]

These guys kinda did that with QM vs Toyota...

mmmmmmm...... "ish". You are right by saying "kinda".

That test is a very old one and can demonstrate things like torque sharing, but it is on flat ground and does not put much stress on the drivetrain at all.

Things change a lot when you are on a 20% grade and now you need two stalled wheels to get you over a hump....

The other piece that some seem to not have experienced is the stall problems that the motors encounter on low-speed obstacles. I assure you, I did not dream it, it happens lol.

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