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Many things I saw and experienced throughout my life made me think how would Rivian behave on icy roads with one pedal control . As I know as soon as you remove your foot from throttle regenerative baking mode automatically engaging. I would imagine it might be pretty dangerous if you have next to no traction on icy roads and might lead in to lose of control.
Self driving mode is the whole different topic which brings much more questions along this line.
Anyone any info, experience, thoughts???
There was already a complaint from girls driving rivian in Rebelle rally since it was self braking and making vehicle stack in the send.
 

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pretty sure.Rivian will give us the option to set Regen to certain intensities. Because its built for "adventure"/ offroading.. I am going to venture a guess that Rivian will offer drive modes for Sand/Rock Crawl/Mud and Snow .. just like Land Rover
 

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Many things I saw and experienced throughout my life made me think how would Rivian behave on icy roads with one pedal control . As I know as soon as you remove your foot from throttle regenerative baking mode automatically engaging. I would imagine it might be pretty dangerous if you have next to no traction on icy roads and might lead in to lose of control.
Self driving mode is the whole different topic which brings much more questions along this line.
Anyone any info, experience, thoughts???
There was already a complaint from girls driving rivian in Rebelle rally since it was self braking and making vehicle stack in the send.
I've had similar concerns. Learning to drive includes knowing what to do in emergency handling situations. The more we experience these scenarios the more we develop muscle memory when driving ICE vehicles that don't have these "advanced" systems. As you alluded to, when a vehicle loses traction you stop accelerating, don't touch the brake and instead attempt to steer out of it.

I've brought up my regen concerns in other forums and the vast majority of the members driving EVs with regen say it's not an issue. Personally, I'm still not convinced. I suspect it will take a new EV driver a while (weeks? months? years? depending how frequently they drive in slippery conditions) to re-develop these emergency vehicle handling skills with one-pedal driving or even two-pedal driving with partial regen.

Since then I think I've potentially tempered my concern some on the hope the engineers factor these emergency scenarios into the software. E.g. if the vehicle has lost or greatly reduced its traction, maybe even starts spinning around, factors in speed vehicle is traveling (low speed not really a concern), etc., and the muscle memory of a legacy ICE driver appropriately takes their foot off the accelerator, the vehicle hopefully uses its input data (e.g. vector controls, traction, direction, speed, cameras/sensors, etc.) to limit or not apply any regen, basically coast, until sufficient traction is reestablished. The specifics behind all this is certainly beyond my paygrade, but as they say I know enough to be dangerous or in this case, concerned, though I do look forward to this turning out to be a non-factor or at least eventually mitigated over time as they collect OTA vehicle driving data, make software changes that get pushed to our EVs. HTMS.
 

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Wouldn't Tesla already of run into this. Regardless if Porsche can make a wheel well that senses water and recommends you switch into 'wet mode' I think they can or already have solved this problem.
 

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Rivian was calibrating drive modes in a series of extensive off-road testing.

"Rivian really does intend for you to take its truck off-road. The company claims it's done extensive off-roading and even rock crawling as part of its development and to calibrate the many drive modes of the off-road terrain selector. You haven't heard about it because all the prototypes were disguised as F-150s."
 

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My Velar can tell when any of my wheels has lost traction and compensate. I fully expect the Rivian to be even more capable, given the target demographic.
 

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You need to think of regen braking as being more like downshifting a traditional vehicle vs applying the brakes. And downshifting is one of the better ways to control speed on slippery roads. Regen is essentially resistance in the motor, just like downshifting. To avoid too much regen causing the wheels to lock and slide, you’ll learn to feather your foot off of the accelerator to slow down vs completely taking your foot off like you would with traditional braking system. Although different, its prettty intuitive, so within a week it will all seem very natural. Biggest challenge is if you have multiple vehicles, one with regen and one without, and go back and forth between them.
 
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Wouldn't Tesla already of run into this. Regardless if Porsche can make a wheel well that senses water and recommends you switch into 'wet mode' I think they can or already have solved this problem.
From my understanding Tesla has a low setting for the regen that makes a big difference when driving in the snow. Rivian should have something similar whether it's in a specific drive mode or just as a setting.
 

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You need to think of regen braking as being more like downshifting a traditional vehicle vs applying the brakes. And downshifting is one of the better ways to control speed on slippery roads. Regen is essentially resistance in the motor, just like downshifting. To avoid too much regen causing the wheels to lock and slide, you’ll learn to feather your foot off of the accelerator to slow down vs completely taking your foot off like you would with traditional braking system. Although different, its prettty intuitive, so within a week it will all seem very natural. Biggest challenge is if you have multiple vehicles, one with regen and one without, and go back and forth between them.
I second that. This is how I drive our Tesla: max regen all the time, feather with your foot. It took about five minutes to get used to.
 

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This is a really good question with a fundamental relation to vehicle use. It really gets you thinking. My winter driving instructors taught me a number of things, and I wonder how these apply in an EV situation. And I relay these to my kids and anyone else who wants some tips on snowy/icy driving. 1. Drive like there is an egg under your foot. No rapid mashing of brake or accelerator. 2. Do one thing at a time. Brake, accelerate, steer but never together. 3. When there is a chance of skidding (like when you are about to go down a snow covered hill) or when you start to skid, pop it in to neutral and 4. pump the brakes: ON>Release>ON>Release etc till you stop skidding or make it to the bottom of the hill (hopefully under control). 5. Steer into the skid which takes a lot of practice and courage.

So can you pop the Rivian into neutral? Does ABS work by using the braking system or the regen system or both? I can imagine the regen system overslowing the vehicle and precipitating a skid. And what about traction control? On my wife's 540iA, you had to turn off the traction control so the wheels could spin in order to climb our snow covered hill. Leaving traction control engaged would overcompensate and stop the wheels turning. I still think a good set of Blizzaks (or others) eliminates 75% of winter driving problems(as long as you use the 5 recommendations from above).
 

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I agree with what Cale said, just above.
I would suggest that everybody should find a safe, open place next time it ices or snows (different), and play around. Test the limits; do donuts, get it sideways and practice recovering. When spinning out of control on a busy highway is not the time to try to remember what your instructor said.
 

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I would suggest that everybody should find a safe, open place next time it ices or snows (different), and play around. Test the limits; get it sideways and practice recovering. Spinning out of control on a busy highway is not the time to try to remember what your instructor said.
Note: scout out future hooliganing place before all the little curb stops get covered with snow.
 

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Yes indeed. Practice. Get the feel of a car pushing into a corner, or snap oversteer when you punch it (rwd) on a slick surface. Learn how not to panic and how to recover. Unfortunately, in Northern NJ, the cops are really tight sphinctered (and rightfully so) when they see someone hooliganing (loved that term) in a parking lot. Too much liability. Even if you are there to have a car control clinic with your teen driver. The state required instruction teaches them how to obey the law. But I think half of the 6 hours would be better spent on a skid pad.

I will be very interested to learn how the EV dynamics play in all of this. The fact that the batteries and therefore the center of gravity is so low in these EVs must help. My wife's 540 was a bulky, heavy, powerful car with 50/50 weight balance. It was RWD,. But with Blizzaks and a light foot, it was very controllable in the substantial snow/slush of NJ. I can see how settings for different road conditions would be helpful. I just need to get a Rivian before my 2008 200K MDX dies. Otherwise it will be another thermal engine for me. Come on Rivian! Get them built. I am sooo ready!
 

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BMW used to offer a performance driving school (I don't know what Covid has done to that) and it'd be nice to be able to take a supervised Rivian through controlled situations ranging from level 3 self driving to skid pads and rock climbs and sand and mud and wading.
 

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3. When there is a chance of skidding (like when you are about to go down a snow covered hill) or when you start to skid, pop it in to neutral
I agree with everything except this. Lower gear is far better than neutral when going down a hill. It provides a nice constant resistance to all four wheels (if you have 4WD) and helps keep speed down without relying on brakes which tend to lockup more easily. Additional brake pumping may be needed on really steep inclines, but I’d never put my car in neutral in snow/ice. You’ll lose a lot of control and recovery options when you do that.

As to whether you can put an EV in neutral, yes you can. That’s needed to allow the car to go thru automated car washes as well as other things.
 

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I agree with everything except this. Lower gear is far better than neutral when going down a hill. It provides a nice constant resistance to all four wheels (if you have 4WD) and helps keep speed down without relying on brakes which tend to lockup more easily. Additional brake pumping may be needed on really steep inclines, but I’d never put my car in neutral in snow/ice. You’ll lose a lot of control and recovery options when you do that.

As to whether you can put an EV in neutral, yes you can. That’s needed to allow the car to go thru automated car washes as well as other things.
My experience is far different from yours. In neutral, the wheels are no longer being driven. The only thing propelling the vehicle then are the kinetic energy (similar to momentum) and gravity. So you take out the wheels being connected to the engine which is a source of forward movement. Now you have only 2 sources of propulsion of the vehicle to contend with, momentum and gravity. An if you start out VERY slowly, you can minimize kinetic energy's influence over the vehicle. Keep pumping those brakes as you gain a little speed as you descend the hill. If you leave it in gear, the motor at idle is still providing rotation to the wheels countering your braking. I eliminate that by being in neutral. I control the speed through braking, not allowing any additional movement via the engine. I found that the speed that the vehicle wants to travel at while in the lowest gear may be too fast for conditions. Neutral puts me in control of the speed. And in a skid I definitely don't want the engine turning the wheels. It works very well for me. Your experience is different. It is what you are comfortable with and have experience with that you should continue to employ. I respect your opinion.

And as for losing control and recovery options I have a lot of experience watching that. I am one of those rescue people that sits in a medical car and responds to motorsports crashes. Once a skid has begun, we say "Mr. Newton was driving" and very few have the ability/skill to power out of loss of adhesion to the track. Especially when they make it on to wet grass. They end up in a barrier, or in a gravel trap, or some run-off area. I find that dirt track drivers who migrate to asphalt often have the skill to recover from a skid because they are used to sliding the car all over the track. Tony Stewart is a great example of that. Yes, the speeds are much higher, but Mr. Newton has something to say in all crashes.
 

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4 Low > Neutral in every way. I would never go for neutral over 4low in a snowy situation, but I also wouldn't be driving up or down a big snowy hill without being in 4low in the first place :)
 

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I think you are both right. It depends on the slope of the hill, and the speed you want to be going. Also, what type of transmission you have: manual, automatic (which has creep), or EV with regeneration. I am looking forward to experimenting with the EV before pontificating on it.
 

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Why would you pump your brakes in a modern vehicle? Press the pedal to the floor and let the antilock do its thing. It can pulse the brakes a heck of a lot faster than you can. I drive a dual motor (all wheel drive) Tesla Model S in MI and the car handles great in the snow. In fact, two days after I took ownership, I got caught in an ice storm in Detroit. Freeways were a solid sheet of ice. Yes it was nerve wracking, but I just did what I always do when driving in slippery conditions....light acceleration, light braking (or in this case easing off the go pedal), no sudden turns. Yes there was some slippage, but car handled a heck of a lot better than other vehicles on the road at the same time. As others have said, take a bit of time to get used to how the region kicks in as you come off of the go pedal (accelerator) and you'll very quickly develop the appropriate muscle memory.
 
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