Inkedsphynx

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You are 100% correct that people can choose and will do what they want with their Rivian. But you have to take into account that Rivian's demographic *are* those that go adventuring/off-roading. They're showing prominent features (gimmick or not) that are aimed towards that lifestyle. To promote a feature to then axe it is foul play. Again, I don't mind Tank Turning getting delayed as long as it's in the name of perfecting the program and algorithm. But if the project gets canned, Rivian is going to face some issues from backlash from customers that *want* this feature.
I am one of those, both demographically and that want the feature. Rivian will face no backlash from me if it doesn't come to fruition. There's a vast difference between 'we can't give this to you safely' and 'we decided to can this feature for no particular reason'.

I don't need tank turn. I'd like it, sure. If lack of tank turn is the reason people want to give up their pre-order, I'm always happy to move 1 spot up the queue :D
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E.S.

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Lets face it. No one 'needs' Tank Turn. It is undoubtedly a gimmick. However, it is a gimmick *I* want, even if I use it sporadically. Will not having this feature right stop me from getting this vehicle? No. But it is one (amongst a plethora of) reasons why I want this vehicle. To buy this car and not have this feature implement (even if later on) will feel like the vehicle will not be 'complete' for me.
 

BigSkies

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The more I think about "Tank Turn" (or 4-wheel control more generally), the more I think Rivian and the broader public are missing the point. Maybe I'm completely missing something though.

Spinning in circles at 30mph+ is an interesting but useless gimic.

Carefully turning at 2-5mph to avoid an obstacle is an incredibly valuable maneuverability feature in tight spaces. I could see some interesting use cases for parallel parking and maneuvering in and out of tight urban parking spaces. In my case, it would be really useful getting out of my garage on garbage day, when my neighbors garbage cans are 10 ft behind my driveway.

I'm no engineer, but it seems like a lot of the safety issues with spinning and drifting off course go away when you're talking about ~5mph maneuvers and turns from 1 to 90 degrees instead of trying to turn your truck into a spin-dry cycle. Sure, there would still be some drift, but it would be much smaller in relation to the overall maneuver.
 

Autolycus

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The more I think about "Tank Turn" (or 4-wheel control more generally), the more I think Rivian and the broader public are missing the point. Maybe I'm completely missing something though.

Spinning in circles at 30mph+ is an interesting but useless gimic.

Carefully turning at 2-5mph to avoid an obstacle is an incredibly valuable maneuverability feature in tight spaces. I could see some interesting use cases for parallel parking and maneuvering in and out of tight urban parking spaces. In my case, it would be really useful getting out of my garage on garbage day, when my neighbors garbage cans are 10 ft behind my driveway.

I'm no engineer, but it seems like a lot of the safety issues with spinning and drifting off course go away when you're talking about ~5mph maneuvers and turns from 1 to 90 degrees instead of trying to turn your truck into a spin-dry cycle. Sure, there would still be some drift, but it would be much smaller in relation to the overall maneuver.
If you read the Motor Trend article about it, you’d see that what they learned with their early development is that you basically can’t do a low-speed tank turn because the tank turn requires high wheel spin, which means a high rate of car spin.
 

godfodder0901

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The more I think about "Tank Turn" (or 4-wheel control more generally), the more I think Rivian and the broader public are missing the point. Maybe I'm completely missing something though.



Spinning in circles at 30mph+ is an interesting but useless gimic.



Carefully turning at 2-5mph to avoid an obstacle is an incredibly valuable maneuverability feature in tight spaces. I could see some interesting use cases for parallel parking and maneuvering in and out of tight urban parking spaces. In my case, it would be really useful getting out of my garage on garbage day, when my neighbors garbage cans are 10 ft behind my driveway.



I'm no engineer, but it seems like a lot of the safety issues with spinning and drifting off course go away when you're talking about ~5mph maneuvers and turns from 1 to 90 degrees instead of trying to turn your truck into a spin-dry cycle. Sure, there would still be some drift, but it would be much smaller in relation to the overall maneuver.
If you read the Motor Trend article about it, you’d see that what they learned with their early development is that you basically can’t do a low-speed tank turn because the tank turn requires high wheel spin, which means a high rate of car spin.
You also can't do it in urban environments i.e. on pavement.
 

BigSkies

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You also can't do it in urban environments i.e. on pavement.
Interesting. It's not that I don't believe them, I just don't understand it. What makes rolling the tires slowly in different directions different than rolling them slowly in the same direction? There shouldn't be any difference in surface friction.
 

R_1_T

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Lawyers ruining the fun...
 

Autolycus

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Interesting. It's not that I don't believe them, I just don't understand it. What makes rolling the tires slowly in different directions different than rolling them slowly in the same direction? There shouldn't be any difference in surface friction.
Read the article. It explains all of this. The truck isn’t a square. To get the truck to spin in place, the wheels must slip sideways.
 

crashmtb

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Interesting. It's not that I don't believe them, I just don't understand it. What makes rolling the tires slowly in different directions different than rolling them slowly in the same direction? There shouldn't be any difference in surface friction.
Have you never done a donut or otherwise slid a car around? You need wheel speed to break traction.
 

Zoidz

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Interesting. It's not that I don't believe them, I just don't understand it. What makes rolling the tires slowly in different directions different than rolling them slowly in the same direction? There shouldn't be any difference in surface friction.
Watch the video. Don't look at the tires, look at the vehicle body. If you pay attention closely, you should recognize that the front end and rear end of the vehicle are moving *sideways*, not moving in the rotational direction of the tire. Think about that - it means that the tires are sliding *sideways*, which is not normal. To reduce that sideways friction resistance, the tires are spinning at high speed. Due to the slippage, the tires can more easily move sideways.

A rough analogy might be a handheld vibrating sander. When it's not vibrating, it takes a lot of effort to push it. But when it is vibrating at high speed, you can push it in any direction, including rotating about it's centerpoint.

In physics terms, normal driving involvesonly static friction on the tire (no slippage). Tank turn involves kinetic friction (slippage).


 

sub

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Of course there are very few locations were the tank turn would be safe and legal, but there are even fewer locations where it is safe and legal to drive faster than 80MPH. There would be outrage if manufactures started capping the top end at 80 just because there are few places where it was safe and legal to drive that fast. Tank turn is not a feature I would ever use, not even to just to test to see if it really worked. But "if we enable this, people will be stupid and crash" seems like a terrible reason to not enable it. It shouldn't be Rivian's responsibility to ensure that people don't do stupid stuff with the vehicle.

But I am also surprised to see that some people didn't think it was obvious that you would be asking for trouble if you did a tank turn anywhere other than in a large, flat, empty field. So perhaps Rivian was right to cancel it, at least with high speed no one will claim that they didn't know that traveling way above the speed limit was unsafe, even if they do it every day.
 
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BigSkies

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Thank you for that. I can visualize it much better looking at the video that way.

I do still hope they are able to do useful stuff with the flexibility of 4-tire control.
 

Daedalus

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Hang on peeps, I got this:

5mh6a5.jpg


:D

Seriously though, it was never more than a novelty. I'm still really eager for the truck ... despite this and the more useful items that have been dropped.
I remember hearing that the R1S would be using Lidar for its Driver+ system - I think this was also removed.
While I am not getting the R1T, I always thought that Tankturn was a gimmick (especially since it was limited to where it could be used). That said, was anyone ordering the R1T claiming that tankturn checked some requirement that they had - was that the make or break feature for them, because there is a teacup ride at disney made just for you....
 
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