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JeremyMKE

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They have a sense of humor....

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I am actually very curious about this. I really want a valet mode. More often however I need a my elderly father borrows the truck to get some mulch mode. Or a wife needs to use the truck mode...

I dont want them to end up like the test mule in SoCal...
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CommodoreAmiga

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I may be one of the few that actually likes this. I had a depressed teenager with thoughts of throwing herself out of a moving car. Too easy for her to flip the child lock on the door side, had me always double checking. This would have been a life saver. Fringe use case, I know...

Edit: yes, dark humor pun intended...
My current vehicle lets me toggle the child locks electronically (button on drivers door). I was surprised Rivian didn’t just put it in the center screen.
 

Joewillie

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Braking.
You are 100% correct, maintaining a perfectly neutral position in a one pedal driving setup should be the same as coasting. I just find it way harder to do so than simply taking my foot off the accelerator. I probably would learn to do so, but I have tried on my VW and don’t like it. If I want to slow down slowly in the most efficient way possible, I want to coast. I think having “provide power” in one pedal and “slow down” via another pedal is a better use experience than needing to thread the needle with one pedal. Blended breaking is an elegant solution to doing so with efficient regeneration.

That said your explanation on why blended breaking is not available does shed new light on to that situation that I didn’t know. I appreciate that and it explains why VW/Audi seem to be different than many other EVs.
Braking.
 

ajdelange

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I’ve really only had two issues with all of the updates I have had.
Apologies for off topic but warning to Tesla drivers. If you use PIN security turn it off. The last OTA update causes problems like "Park assist not available..." displays and inability to access Sirius. If you try a reboot to fix these problems it can brick your touchscreen computer and, if you have PIN enabled, your car.
 

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SANZC02

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Apologies for off topic but warning to Tesla drivers. If you use PIN security turn it off. The last OTA update causes problems like "Park assist not available..." displays and inability to access Sirius. If you try a reboot to fix these problems it can brick your touchscreen computer and, if you have PIN enabled, your car.
AJ,
Thanks for the heads up. I only have pin enabled to lock the glovebox, never enabled it to drive the car. I also do not have the hardware for Sirius, I wonder if the bug is in that portion of the code.

Curious what update version that was in. I currently have 2020.48.37.6 if it is later than this I will keep an eye out.
 

ajdelange

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Can you explain why low regen and coasting is more efficient?
Regen attempts to capture some of the kinetic energy in the vehicle but as regen is not 100% efficient it cannot capture it all. This energy is lost to heat and is, in effect, just as pressing the brake pedal does. If you can manage your speed profile without ever pressing the brake pedal or using regen the only energy you will waste as heat is that which goes to warm the air (drag) and tires (rolling resistance).


I would have assumed that holding the accelerator in a “neutral” position such that you have no acceleration and little to no regen would accomplish exactly the same thing. In an EV, the motor has to provide some energy to “coast” like this, regardless of your regen setting, as the motor naturally wants to resist the inertia of the turning wheels to recover electricity.
By positioning the pedal such that the stator field is parallel to the rotor field no torque is generated in either direction and no power is absorbed or generated. This is the same as coasting.

As for the blended braking, ... I suspect it comes down to a regulatory issue. For vehicles that use blended braking ... the ABS system have control of the regen braking.
If you want to use blended braking, regulations or no, then there must be coupling between the brake pedal and the motor control systems. Clearly this is more complicated than a system where one pedal controls motor torque (in either direction) and the other only friction derived torque. But the real advantage of single pedal control is that it maximizes efficiency. From that standpoint you never want to use the friction brake unless you absolutely have to. In a blended system you are going to be into the friction brake region to some extent when you really don't want to be.
 
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ajdelange

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You are 100% correct, maintaining a perfectly neutral position in a one pedal driving setup should be the same as coasting. I just find it way harder to do so than simply taking my foot off the accelerator. I probably would learn to do so, but I have tried on my VW and don’t like it.
You already know how to do it and have been doing it for years. You have just never really thought about it because for most of your life the skinny pedal only went from a very small negative g value to a much larger positive g value. You have always moved your foot to get the system g's you need: 0 for cruise at constant speed, in for acceleration, back for deceleration. What is different now is that the negative g's available from the skinny pedal are greater in magnitude so that you don't have to switch over to the fat pedal as soon or as often. Ideally you will never touch it.


If I want to slow down slowly in the most efficient way possible, I want to coast. I think having “provide power” in one pedal and “slow down” via another pedal is a better use experience ..
It has never been that way. Why do you want it that way now? Think about this. In your ICE vehicle what do you do when you see the brake lights come on on a car well in front of you? Do you go immediately to the brake or do you just feather the gas pedal only resorting to the brake if feathering the gas is not slowing you down enough? I hope it's the latter because my wife does what you are suggesting and it makes me car sick. Assuming it is the former things aren't going to change with regen. It is just that your trips to the fat pedal will become fewer and farther between eventually reaching near 0 and you will be wondering why you were ever concerned about this. Your "don't like it" will cahnge to "like it".
 

ajdelange

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I, too, prefer the two pedal systems, so maybe there will be software options down the road.
I doubt it. The engineers at Tesla have apparently figured out that the best system in terms of the clear goals of most miles on least battery and system complexity is single pedal and Rivian's engineers are pretty bright too.


The Taycan has an incredible system (this article does a good job detailing it) and it’d be nice to see something similar from Rivian.
The Taycan system is incredible in that I can't believe anyone would put a system like that in a vehicle intended for day to day use but I guess the Taycan is really more about being "upscale" than the Tesla or Rvian vehicles. The linked article, typical of automotive journalism, emphasizes that the Taycan has more than double the S regen and implies that this must be a good thing. Reading this I think "Gosh, his is bigger than mine. I'd better get one like his" but then I started thinking about it a bit. The Telsas take up to about 80kW of regen (warm battery below about 85% SoC). What would be the advantage of it being able to take more? Answer: none. Were any more needed there would be situations where what is available in inadequate, that is, situations where I would have to go to the fat pedal and those just don't arise. Conclusion: for the kind of driving I do in a Tesla X 80 kW is adequate (or more than adequate).

I guess we’ll see, but it seems to be a personal preference what folks prefer.
Yes we will. If we find that we are using the brake pedal when the regen in full on then we will know that more regen is needed at which point Rivian will do the tradeoff against rough treatment of the battery and range. But is is, IMO, very unlikely that they will go to a blended system. One reason for this is that I'm pretty sure that once people drive single pedal for a while they will appreciate its advantages.
 

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eemri

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I doubt it. The engineers at Tesla have apparently figured out that the best system in terms of the clear goals of most miles on least battery and system complexity is single pedal and Rivian's engineers are pretty bright too.


The Taycan system is incredible in that I can't believe anyone would put a system like that in a vehicle intended for day to day use but I guess the Taycan is really more about being "upscale" than the Tesla or Rvian vehicles. The linked article, typical of automotive journalism, emphasizes that the Taycan has more than double the S regen and implies that this must be a good thing. Reading this I think "Gosh, his is bigger than mine. I'd better get one like his" but then I started thinking about it a bit. The Telsas take up to about 80kW of regen (warm battery below about 85% SoC). What would be the advantage of it being able to take more? Answer: none. Were any more needed there would be situations where what is available in inadequate, that is, situations where I would have to go to the fat pedal and those just don't arise. Conclusion: for the kind of driving I do in a Tesla X 80 kW is adequate (or more than adequate).

Yes we will. If we find that we are using the brake pedal when the regen in full on then we will know that more regen is needed at which point Rivian will do the tradeoff against rough treatment of the battery and range. But is is, IMO, very unlikely that they will go to a blended system. One reason for this is that I'm pretty sure that once people drive single pedal for a while they will appreciate its advantages.
I'm not too worried about the regen aspect but rather the preferred driving styles and experience. I prefer the two pedal approach - perhaps I'm old school, perhaps it makes it easier for me as I switch between cars that still require me to use the brake pedal. But the Porsche engineers are pretty bright too and manage to do some incredible things on their cars. The brake feel in the Taycan is really good considering there is regen and then traditional brakes (pistons, calipers, discs) involved. I appreciate that driving experience.

I was mostly just hoping for options around the regen that allowed folks with either preference to get "their way". I'll see how it feels when I get mine -- there's a lot that'll be different about the Rivian so I'm already expecting to having to do things a little differently :)
 

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I drive an e-tron, which has a very similar system to the Taycan, and I wanna throw in my vote for "I wish Rivian had the same system". As has already been said: yes, I agree that any automaker should *allow* heavy regen on the accelerator as an option, but they should also allow for zero with full coast. Managing you speed and coasting will always be more efficient than regen. Regen is more effecint than friction brakes, but it's never going to be more efficient than simply not scrubbing speed at all. Converting from kinetic energy to electric energy is not 100% efficient.

The thing I don't get is why anyone would argue that the VW/Audi/Porsche brake by wire system is a bad idea. It's brake by wire. It's not like the system on a Bolt, which mixes both friction and Regen. The VW system uses 100% regen up until the point that you need more force, and then it adds the friction brakes. It forces the most energy recovery *regardless* of driving style. It feels very very much like a normal braking system, as opposed to a mediocre blended system like so many hybrids have.

Interesting reading here starting on page 56: https://static.nhtsa.gov/odi/tsbs/2019/MC-10155750-9999.pdf
 

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So I'm trying to figure out the invocation of the Alexa integration. Since there is no infotainment information in the owner's manual that has been released, I assume there is a separate manual coming.

The owners manual talks about the left thumb control for audio and phone. It appears that all button functions are accounted for.
The manual goes on to says: "The right thumb control is for Driver+ features." Then describes the usage of those buttons. It does not say what pressing the center of the right side thumb control does, except its use for Manual Trailer Braking.

I'm hoping that there is a way to hit a button to wake up Alexa. Wake word recognition is sometimes flaky, and difficult when listening to music or other noise is occurring like the giggles and screams of passengers in those 3 second 0-60 runs. It'd have thought pressing the center of the right thumb control would be a wake event for Alexa, but the trailer braking has me confused. Anybody have any experience to clarify this? @DuckTruck ?
 

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If the only way to regen is with the accelerator, I just hope they make it really easy to toggle quickly between coast and regen modes. Heavy regen is great in the city, but not on a highway. Not being able to shift your foot for hours on end is NOT comfortable.
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