Not possible to turn off 1 pedal driving?

[tbinmd]

And still, nobody has defined what “coasting” means and everyone is using it differently while saying the same thing and arguing.

coasting is that the car does not slow down due to regen, it's free to roll without any resistance. Think about coasting on a bike. If you coast in a car and are on an incline it should pick up speed. A better way to define it is that coasting in a car is the drive train is disconnected from the wheels, the wheels a free to move faster or slower depending on the physics and not the drive train. In a manual car it's pushing on the clutch and holding it in.

Any EV with one pedal driving does not coast.

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[SwampNut]

coasting is that the car does not slow down due to regen, it's free to roll without any resistance.

100% impossible on most, if not all EVs. It would only be possible if they all had a mechanical disconnect like the rear motors on the R1 quad.

Think about coasting on a bike.

I know exactly what it is and what it means. You are arguing for something that's impossible since you don't actually understand the physics and mechanics involved.

Any EV with one pedal driving does not coast.

Nor does a car with an automatic transmission, under your definition. What cars do? Only a manually shifted car or a DCT if programmed to do so (and they are not).

 

[Swezey]

? Well, yeah, but it immediately starts slowing to a halt eventually, unless you're in Roll/Coast mode... which apparently Rivian doesn't offer. That's the OP's point.

Re-read what you replied to. You missed it. You can coast in a Rivian.

Nope, not at all, in a Tesla or Rivian with one pedal driving you cannot coast. The vehicle starts slowing down due the regen. When there's coasting, the vehicle can roll freely.

This is wrong. Modulate the pedal, and you can coast. Refer to the dash and view the power meter.

coasting is that the car does not slow down due to regen, it's free to roll without any resistance. Think about coasting on a bike. If you coast in a car and are on an incline it should pick up speed. A better way to define it is that coasting in a car is the drive train is disconnected from the wheels, the wheels a free to move faster or slower depending on the physics and not the drive train. In a manual car it's pushing on the clutch and holding it in.

Any EV with one pedal driving does not coast.

Incorrect definition. The drivetrain in an auto or manual does not fully disconnect. The transmission is physically linked to the wheels. That's part of the drivetrain. It's the engine that gets disconnected via the clutch or torque converter.

In an EV, the electric motor is computer-controlled to consume power from the battery (accelerate), do nothing (coast), or supply power to the battery (regen). Same shit, different tech.
All this happens from 1 pedal and Rivian's algorithms.

You CAN coast in an EV.

 

[SwampNut]

What is the meaning of the word, "is?"

Incorrect definition.

Dictionaries disagree with you.



Coasting in a car refers to driving with the engine disengaged from the wheels (either by shifting the transmission into neutral or holding the clutch down) or simply taking your foot off the accelerator and letting the car roll freely while still in gear. [1, 2, 3]
The definition and implications of coasting vary depending on how it's executed and the type of vehicle you drive:

Coasting in Neutral (or Clutch Held Down)

• What it is: The act of disconnecting the drivetrain from the wheels so that the car rolls solely on momentum. [1, 2]

 

[Swezey]

What is the meaning of the word, "is?"

Dictionaries disagree with you.



Coasting in a car refers to driving with the engine disengaged from the wheels (either by shifting the transmission into neutral or holding the clutch down) or simply taking your foot off the accelerator and letting the car roll freely while still in gear. [1, 2, 3]
The definition and implications of coasting vary depending on how it's executed and the type of vehicle you drive:

Coasting in Neutral (or Clutch Held Down)

• What it is: The act of disconnecting the drivetrain from the wheels so that the car rolls solely on momentum. [1, 2]

Notice how this definition doesn't even address EVs?

It actually proves my point, did you even read it?

The definition and implications of coasting vary depending on how it's executed and the type of vehicle you drive:

So yeah, refer to my previous post. As it still stands.

 

[SwampNut]

Notice how this definition doesn't even address EVs?

Notice how it doesn't matter?

It actually proves my point, did you even read it?

I did read it, and perfectly pointed out why it's nonsense.

 

[Swezey]

Notice how it doesn't matter?

I did read it, and perfectly pointed out why it's nonsense.

Yeah, the whole "doesn't matter" line doesn't work on me. It only "doesn't matter" to you as it gives you the "out" to walk away with your ego intact. Others, with reading comprehension, know better.

Also, this isn't high school.
It does matter, for many reasons, because people are misinformed. And we all know what misinformation can cause.

The ability to produce b.s. is substantially easier than it is to refute it. Do the world a favor and stop producing it.

 

[SwampNut]

Yeah, the whole "doesn't matter" line doesn't work on me. It only "doesn't matter" to you as it gives you the "out" to walk away with your ego intact. Others, with reading comprehension, know better.

Also, this isn't high school.
It does matter, for many reasons, because people are misinformed. And we all know what misinformation can cause.

The ability to produce b.s. is substantially easier than it is to refute it. Do the world a favor and stop producing it.

LOL!

 

[2kwik4u]

the EV will never coast in that definition.

Rivian motor with permanent magnets won't but induction style motors should be able to (or at least similarly to driveline lag in an ICEV). Also, Rivian has a clutch on multiple motor configurations. Would wear it quickly, but absolutely allows for "true coasting".

Not that I think 1 pedal driving is all that bad or hard for that matter, I use it exclusively; even when off-road and towing. However it should be noted that a true "coast" with an induction motor is still more efficient than constant high level regen. Any energy conversion yields losses, so once you've changed electric to kinetic it's most efficient to just leave it there.

Personally, I would prefer a software defined "coast" with regen blended into the brake pedal. Rivian has excellent driveline calibration (One of the things I'll miss dearly when I move on), and I have no doubt they could make this happen.

 

[SwampNut]

We're gonna have 26 pages of purposely ignoring/changing/arguing about nonsense. I'm in, it's a really slow week.

100% impossible on most, if not all EVs. It would only be possible if they all had a mechanical disconnect like the rear motors on the R1 quad.

 

[VSG]

Oh stop it with all this "coasting" nonsense. However you define it, "coasting" is not more efficient than regenerative braking, when comparing apples to apples.

If two identical cars travel identical routes with the exact same velocity profiles (velocity as a function of time), the amount of energy they need to expend is exactly the same. The same, exactly, whether they use regenerative braking or they "coast".

The difference in efficiency comes because with regenerative braking one of the cars can recover some of the energy expended when decelerating, vs pissing that energy away as heat loss. Worst case, if there is no braking involved ever, the two cars will use the same amount of energy. But any real travel in a real vehicle requires braking at some point.

If you think accelerating to 100mph then "coasting" until you come to a stop is a more efficient way to travel than accelerating to 50mph and keeping the speed steady until the end when you brake hard, well those are also very different velocity profiles aren't they? Not comparable. You can do the same if you have regenerative braking, and you will end up using the same amount of energy.

And the other thing is, the velocity profile isn't really discretionary. If you travel on a road with a 50mph speed limit, you accelerate to 50mph and hold it there until you need to stop, then you decelerate. If in the middle another car gets in your way, you might have to brake too. NO ONE drives by accelerating to twice the speed limit (so that the average velocity will be the speed limit) and "coasting" the rest of the way to a stop, then repeating that over and over again. And if that's really what you want to do to minimize energy use, then you can do the exact same thing with regenerative braking. Coasting is never more efficient that regenerative braking (for the same velocity profile), and for any practical velocity profile coasting will always be less efficient.

Note: The way to reduce energy usage is to travel slow - energy lost to aerodynamic drag is proportional to the square of the velocity, so you win big by slowing down. Dropping your speed in half will save you 75% of the energy lost to drag.

 

[DanDibs58]

If you let off the accelerator just enough that you're not sending power to the car, and you're also not activating regen, the car is then coasting like a Porsche EV or any gas car. Well, better than the gas car because there is usually some engine braking.

A lot of people don't understand this so I'll repeat: you can successfully, fully, 100% coast in any EV, no matter the regen setup, if you let off the accelerator to the point that it's neither accelerating or regeneratively braking. It's very easy to do by feel alone. In daily driving you probably do this all the time when matching speed with other cars on the highway and didn't even know it. I spend a lot of time coasting in traffic simply by where I end up putting the accelerator to maintain my speed relative to other cars.

The only way a person might never do this is if they let fully off the accelerator any time they need to reduce speed, even a little, which would be a strange thing to do.

I have successfully coasted with a 1-pedal system for 8 years in my 2018 Model 3, with regen set to full. It's very easy.

My definition of coasting is like pushing out the clutch on a car with a manual transmission or putting it in neutral with an automatic. Engine is idling. I guess the EV version of that would be the motor at zero revolutions but not slowing the car down - as I noted, like 'Roll' mode in my Tesla. I'm not familiar enough with the choices in a Rivian but from what I've read, there is no setting comparable to 'Roll' mode in the Tesla.

Coasting broadly refers to moving forward using only momentum or gravity, without applying power from an engine or physical effort.

 

[VSG]

However it should be noted that a true "coast" with an induction motor is still more efficient than constant high level regen. Any energy conversion yields losses, so once you've changed electric to kinetic it's most efficient to just leave it there.

Nope. Apples to oranges.

 

[2kwik4u]

Nope. Apples to oranges.

Explain how converting kinetic energy to electrical energy is more efficient than using that energy to keep the car moving forward. If you can do that, then you're next in line to buy my perpetual motion machine.

 

[MaskedRacerX]

100% impossible on most, if not all EVs. It would only be possible if they all had a mechanical disconnect like the rear motors on the R1 quad.

Not all, and not necessarily "mechanical", I've brought up the BMW iX implementation in this conservation a number of times.

And to be clear: if things aligned differently, I would've seriously considered an R2 knowing the OPD execution (and the lack of CarPlay for that matter), these are things I like, I prefer, the iX being able to toggle D/B mode (coast/regen) on the fly is nice - choices are nice - but if other things are compelling enough, they're not complete deal breakers.

(FWIW, don't need the R2 anymore, wouldn't lease one [if we did] with the current numbers - so it's no longer being pursued - but not due to OPD only )

An iX5 x60 or iX5 M70 will be the iX replacement

I don't even know what that response means, other than you can't have a rationale conversation, so HERF DERF I DO LAUGHY ICON DERFDERFDEF ...

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