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paddle shifters yes or no?

Eager2own

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In the Tesla that is done by releasing a little pedal pressure - as much as you want for the amount of slowing you want.

In the Tesla you wouldn't shift (you can't) but rather just let off more pressure to the point where the car comes to a full stop.

So I guess the question is as to why you prefer to do it in two stages instead of one. Or maybe you don't. Perhaps that is imposed by the Bolt's architecture?
I don’t think the issue is that folks don’t know how regen braking works. There’s already at least one thread dedicated to what level of regen is the right level:
https://www.rivianforums.com/forum/threads/regenerative-braking-capacity.92/

I don’t want to just restate all 10 pages of comments on here but suffice to say that not all agree that constant max regen is best. Some may prefer (parrticularly on highways where much of driving is coasting) to not have max regen unless they are pressing the go-pedal to the “neutral” point, but rather to be able to take foot of the pedal to coast and only engage max regen on demand with, for example, paddles.
You’ve already stated you feel one-pedal driving is best and don’t understand why anyone would want it any other way but, recognizing that others don’t have to agree, I go back to my first response that the best solution is a system (as other manufacturers have implemented) that allows the driver to select whether to activate aggressive one-pedal mode or not.
Why is that not better than imposing one solution for all?
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cohall

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I guess I need to explain how one pedal driving works. To accelerate you press the pedal towars the "fire" wall. To decelerate you let it off a bit. Just as the amount of acceleration depends on how far you push the pedal in the amount of deceleration depends on how far you back it off relative to the "neutral point". At the neutral point you are still pressing the pedal but there is no torque being applied to the wheels and none being absorbed from them. The power meter reads 0. To "brake" you let the pedal move back further and the regen commences with vigor depending on how far back you let the pedal move. Only when your foot is completely off is "full" regen applied. You will find you have no problem in snow because even in full regen the anti-skid system won't absorb torque to the extent that slip occurs.
I'm well aware of how one-pedal driving works, but thanks.

In an emergency skid situation, I do not want to have to try and remember where the 'neutral point' on my pedal is and try and find it in a fraction of a second. My instinct has been and always will be to instantly remove my foot from the pedal, coast until control is regained, change my pants, and keep driving.

If you ever skied/boarded and hit a patch of hidden ice, you know what I'm talking about. Keep the skis pointed down hill until you're past it, then recover. Hitting the 'brakes' will just cause pain and some embarrassment, especially if you're under the lift.

The consequences in a 6000lb truck are much more dire.
 

azbill

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So I guess the question is as to why you prefer to do it in two stages instead of one? Or maybe you don't. Perhaps that is imposed by the Bolt's architecture?
If I am in one pedal driving I too can let off gradually to slow the car down, I do that all the time in city driving. It just happens to be personal preference, when I am on the highway, I do nto do that. I also was driving in snow last weekend and turned off one pedal, since I did not want to ever have hard regen on the slick road, especially with a front wheel drive going downhill.
 

ajdelange

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I don’t think the issue is that folks don’t know how regen braking works. There’s already at least one thread dedicated to what level of regen is the right level:
https://www.rivianforums.com/forum/threads/regenerative-braking-capacity.92/
https://www.rivianforums.com/forum/threads/regenerative-braking-capacity.92/
Yes, I remember that thread well. As you may recall there were people there vehemently opposed to having any regenerative braking at all. Part of my interest here relates to how or whether peoples perceptions have change since that thread was hot.

I know what my preferences are but I am not telling anyone what his preferences should be. You can lead a horse and all that. And no, I don't understand why anyone would want it decreased and that is what I am trying to find out. I get the impression from your response that you nor the other poster want full "1 pedal driving" preferring to have the pedal regen "gain" have at least 2 values. Note that this is the same as setting the pedal throttle gain to timid or normal. Am I right about this?

Tesla used two have two settings for regen. They don't any more. What, if anything, does this tell us? Would this be a show stopper for those of you who want multiple levels?


You’ve already stated you feel one-pedal driving is best and don’t understand why anyone would want it any other way but, recognizing that others don’t have to agree, I go back to my first response that the best solution is a system (as other manufacturers have implemented) that allows the driver to select whether to activate aggressive one-pedal mode or not.
What is best is to give the customer what he wants. But as Steve Jobs once said "The customer doesn't know what he wants. I haven't told him yet." Is Elon Musk trying to tell us that one pedal driving (fixed, single gain) is best? Will R.J. Scaringe agree? Will you be greatly disappointed if you are forced to accept single pedal?
 
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ajdelange

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OK. I think I'm getting the idea. Thanks for the informative, polite replies. Buuuurp.

I find this fascinating and will go on about it all day if you let me but I don't think I need more. And because of that I can't help but add that if in an emergency situation (ice patch) you take your foot completely off the pedal the vehicle will act just as an ICE vehicle without regen will act that is, control the torque to each wheel as best it can to prevent skidding. The only differences are that it can get torque from the motors and/or the friction brakes.

A newer Tesla Model X does not allow you to turn regen down. It is either full on or full off. I always have it on. I got to experiment on slippery snow a couple of weeks back. Anti skid is flawless with full regen. You don't have to know where the neutral point is. The computer knows.
 
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electruck

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Welcome to the world without transmissions! If you follow through with the purchase of a Rivian you will have gone straight from having a manual transmission to having no transmission... skipping over automatic transmissions altogether.
 

timesinks

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I think the discussion is also confusing max regen and one pedal driving.

Max regen can be achieved by avoiding using the friction brakes to slow the vehicle -- recapturing as much of the deceleration as possible back into the battery pack. There's no reason this has to be accomplished with one pedal driving.

Speaking as a Volt owner, the regen mode (not quite one pedal, but heavy decel on throttle lift) and the paddle (that will nearly bring you to a stop) guarantee that you're slowing using regen. While the brake pedal uses regen, it may also use the friction brakes depending on how hard you press it -- and given it's FWD, the rear wheels can only help slow the vehicle with friction brakes.

So in a Rivian (or probably any AWD EV, though I suspect the 4x motor configuration and resultant lack of any open diffs shines here -- haven't thought through it that hard), you can achieve substantial regen force with all four wheels participating. You Rivian could make that energy capture ability available with throttle lift, a paddle, throttle lift controlled by a paddle, or the brake pedal. The vehicle only has to apply the friction brake if you're pressing very hard on the pedal.

Capturing your momentum into the battery as you slow the vehicle does not have to occur specifically from throttle lift to achieve max regen. And while I love driving the Volt in its regen mode that approximates one pedal driving, I also always use the D mode when driving in the snow. In those conditions, you want a deceleration input to the vehicle to be just as intentional as an acceleration input. Configurability here is a good thing.
 

ajdelange

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I think the discussion is also confusing max regen and one pedal driving.
I think the guys are pretty clear on that. But to be clear: the motors in these cars are completely symmetric machines in that they can produce torque or absorb torque. I think it is pretty clear that there are limits on how much torque a motor can produce. Similarly there is a limit on how much torque one can abosorb. Maximum regenerative braking is achieved when the motor is absorbing torque at that maximum limit. What that limit is depends on a variety of factors.

Max regen can be achieved by avoiding using the friction brakes to slow the vehicle -- recapturing as much of the deceleration as possible back into the battery pack. There's no reason this has to be accomplished with one pedal driving.
The condition of maximum regen really has nothing to do with the brakes. Indeed it can be achieved in a variety of ways or rather the motor controller can be commanded to go to max regen in a variety of ways many of which have been implemented in various OEMs' offerings. The simplest is to use the skinny pedal as the sole (no pun intended) means of controlling regenerative braking torque but other implementations have been tried in which, for example, the brake pedal must be pressed or a paddle displacement determines the amount. With single pedal the software can be set so that the pedal's sensitivity can be set high (a relatively large pedal displacement is required to increase torque by x percent) or low (a relatively small pedal displacement increases torque by x percent). Etc. The designer has nearly infinite flexibility in what he can do and of course we humans have infinite flexibility to chose how we would like to control(s) to look and work.

What I have garnered from this thread is that some of you prefer some control over the loop gain (pedal sensitivity) via auxilliary control of some sort such as a paddle or switch. The other thing that I have concluded is that for whatever reason Tesla has decided that you shouldn't have that option and it isn't because it is more expensive to implement because it has been provided up until recently. My guess is that it has been taken away because single pedal fixed gain has been demonstrated to reduce consumption (Wh/mi) and thus increase range. Being able to claim extra mileage is very important to Tesla. Now this may seem far fetched to some but Musk has revealed that one of the software tricks that got 57 more miles out of the X was modification of regen and friction braking algorithms such that handoff from regen to friction could bring the vehicle to a full stop.

So in a Rivian (or probably any AWD EV, though I suspect the 4x motor configuration and resultant lack of any open diffs shines here -- haven't thought through it that hard), you can achieve substantial regen force with all four wheels participating.
Each motor can provide as much torque as the system wants for that motor, in either direction up to the limits of each motors capablity. There are no differentials - only reduction gearning.

Rivian could make that energy capture ability available with throttle lift, a paddle, throttle lift controlled by a paddle, or the brake pedal. The vehicle only has to apply the friction brake if you're pressing very hard on the pedal.
Rivian has the same infinite flexibility in how it gets a command from you to the individual motor controller. So the question is, of course, what will they do? I am guessing that they will be closer to what Tesla does than to some of the older technology vehicles that have been cited as examples here. But of course I can't know. It is possible that just as you have to give up shifting gears with a BEV when transitioning from ICE you may have to learn a new way of interacting with regen.

Capturing your momentum into the battery as you slow the vehicle does not have to occur specifically from throttle lift to achieve max regen.
Minor point: it is not momentum you are capturing. It is energy and it is not exclusively the kinetic energy associated with momentum but also potential energy associated with change in elevation. This latter leads to the phenomenon where you arrive at a destination with more change in the battery than you left with.


And while I love driving the Volt in its regen mode that approximates one pedal driving, I also always use the D mode when driving in the snow. In those conditions, you want a deceleration input to the vehicle to be just as intentional as an acceleration input. Configurability here is a good thing.
That gets us back to the question as to why Tesla took it away.
 

Eager2own

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That gets us back to the question as to why Tesla took it away.
I think you put too much faith in “because Elon wants this, it must be a good thing.” I don’t think Tesla took away the option because it helps their claimed EPA numbers. Tesla will claim the range under the max regen setting whether or not they give customer the option to change it or not.
One could also ask your question differently too. Why does Chevy give drivers ability to adjust regen? Why does Volvo also provide an option to engage B mode to increase regen? Why is Ford including in the new Mach-E the ability to select between 3 different levels of regen and also a one-pedal on/off switch?
You’ve made it clear that it must be done this way because you prefer it and Tesla has taken away the option, but it’s clear from other responses that not everyone wants to lose all ability to adjust.
(By the way, although you’ve assumed that I’m against the higher setting of regen, that’s not necessarily the case. I may love it. I’m willing to try it but, again, I recognize that what is best for me may not be best for others... and I take no issue with them having the ability have the option.)
 

ajdelange

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I think you put too much faith in “because Elon wants this, it must be a good thing.”
Yes, I do put a lot of faith in Elon and his engineering team. They are smart guys. They did this for a reason.

I don’t think Tesla took away the option because it helps their claimed EPA numbers. Tesla will claim the range under the max regen setting whether or not they give customer the option to change it or not.
Yes, good point. That was a shot in the dark.


One could also ask your question differently too. Why does Chevy give drivers ability to adjust regen? Why does Volvo also provide an option to engage B mode to increase regen? Why is Ford including in the new Mach-E the ability to select between 3 different levels of regen and also a one-pedal on/off switch?
Obviously they think there is an advantage of some sort. Why they are orthogonal to Tesla is the interesting question. Maybe I do put too much faith in Elon. Ask me about this after the earnings numbers come out. [Edit] Oops. Yes, perhaps a little bit too much faith.


You’ve made it clear that it must be done this way because you prefer it and Tesla has taken away the option,
A pattern that I have detected in these forums is that someone decides I'm saying that something must be done some way because I think it's the best way. In this case I have expressed by preference for single pedal but also been pretty clear that I don't think everyone has to accept that. Several times. Then the guy that has accused me comes back and accuses me again. Sometimes this happens several times and I get testy.



but it’s clear from other responses that not everyone wants to lose all ability to adjust.
Yes, I agree. Can we please agree that I agree.




(By the way, although you’ve assumed that I’m against the higher setting of regen, that’s not necessarily the case. I may love it. I’m willing to try it but, again, I recognize that what is best for me may not be best for others... and I take no issue with them having the ability have the option.)
Actually I didn't assume that. I would have suggested that perhaps you might like a different method of control were you to try it but had I done that, well hope you get the point.
 
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Gshenderson

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A pattern that I have detected in these forums is that someone decides I'm saying that something must be done some way because I think it's the best way. In this case I have expressed by preference for single pedal but also been pretty clear that I don't think everyone has to accept that. Several times. Then the guy that has accused me comes back and accuses me again. Sometimes this happens several times and I get testy.
If this is happening repeatedly, then perhaps you should go back and re-read your responses with an open mind (or as open minded as you can be) and ask yourself why. The answer is that far too much of what you write here comes across as arrogant and condescending. Whether you intend it to be or not. But perhaps you just don’t care.
 

DuckTruck

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For me, I switch my Bolt to Drive when on the freeways. When I hit the exit ramp I let off the pedal and like to have mild regen, gradully slowing, like I would with an ICE vehicle. As I near the stop sign or light, I shift to one pedal and can stop the car without using brakes. so, no I do not always want max regen.
I drive my ELR the same way. One-pedal mode is great around town. When combined with the regen paddles, the brake pedal has to feel unloved.
 

azbill

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I drive my ELR the same way. One-pedal mode is great around town. When combined with the regen paddles, the brake pedal has to feel unloved.
One other reason to use drive on the freeway is when I disengage cruise control. If your foot is not on the pedal and synchronized with the cruise control, it brakes to hard in one pedal. With low regen, I can leave my foot off the pedal and deselect cruise control as I near the exit ramp, it smoothly slows down.
 

DuckTruck

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One other reason to use drive on the freeway is when I disengage cruise control. If your foot is not on the pedal and synchronized with the cruise control, it brakes to hard in one pedal. With low regen, I can leave my foot off the pedal and deselect cruise control as I near the exit ramp, it smoothly slows down.
Thanks, azbill! I've never tried one-pedal with cruise, and now I don't think I ever will. I know the Volt and ELR never got the love from the dealers that I think they deserved (very little product knowledge by staff, low future maintenance/repair income, etc.). But they're a great way to run around town without burning gas while still letting you "See the USA, in your Chevrolet. America is asking you to call!" (for those of us old enough to remember that jingle, sung by Dinah Shore) while still getting great mileage in ICE mode, with zero range anxiety.

In the early days of the Volt, I remember a Summer red carpet event In Hollywood where they interviewed Jay Leno on his way in. My recall is that the reporter asked him which of his fantastic cars he was driving that day, and Jay replied he was in his Chevy Volt. When the surprised guy asked him what kind of mileage he gets, Jay said something to the effect of "I don't know, I bought it in January and I'm still on the first tank, even though it's my daily driver." That interview and his review of the ELR on "Jay Leno's Garage" were a big part of why I ended up looking for a Volt or ELR in the first place.

Side note: Since discovering "Jay Leno's Garage" on the MotorTrend channel, with vignettes on YouTube, I think I've seen every episode at least twice. I love that man! If I had a choice of a personal tour of the White House, or his garage, I'd be on the first non-stop flight to Burbank today. In case you're reading this Jay, that's Alaska Airlines flight 3402, arriving from Portland at 6:10 p.m. today. If another day would be better for you, please feel free to message me. My schedule is very flexible.?

Jay,

Another option would be to let you test drive my R1T for your show. I'd gladly meet you and your team wherever you'd like, to allow you have some fun with it. Maybe RJ would join us.

Be well, my friend!
 
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DucRider

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Not exactly about paddle shifters, but relevant to the discussion. Local Model Y owner sent this today:

I noticed this behavior in a Tesla Model Y but it really applies to any car that has “one pedal driving” be it an EV or not.
If you are on on a slippery/icy slope and you come to a stop the HOLD function turns your car into a hockey puck. If the car starts to slip turning the wheel or pumping the brakes will do nothing. All four wheels are being held and the car has no information that you are sliding. In my case I slid 100 yards down the road making a 180 degree spin. Fortunately for me there were small drifts of snow that kept me on the road until I reached the bottom.
It took me a some very long WTF moments before I figured out what the deal was.
If you are a “one pedal driving” fan like I am, be aware! If you are going to drive somewhere slippery then turn HOLD to ROLL. CREEP is better but has its own problem of providing the wheels with power when you might not want it. You have to be in PARK to change this feature so, making the change while driving when you see ice coming is not an option. Your one life saver if you start slipping is NEUTRAL. But you have to have the presence of mind to know what’s happening and then be calm enough to hold the shifter half way toward REVERSE for a full second while you’re sliding into the ditch.
I suspect that REGEN will cause the same problem at speed. At least at-speed you can use the brakes and the anti-lock will keep you on the road. You can also hold the throttle so you are effectively rolling. Just be aware that REGEN is slowing the wheels pretty aggressively. That’s why the brake lights come on.
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