Rivan wants you to cancel your pre March '22 order [?]

[Zoidz]

I don't mean to bore you or the readers of this thread, but the tires are not moving and cannot move "sideways" … tires only roll or slip.

'The vehicle is not moving sideways, either, it's rotating on an axis:
1. Two tires rotating forwards, experiencing the loads of a standing start launch like a 0-60 drag.
2. Two tires rotating backwards, experiencing the loads of heavy braking.

I'm no physicist, but I'd call these moments.

It's a four wheel drift, with one side of the vehicle is drifting forwards and the other side drifting backwards. Rotating around a vertical axis or polar center.

The vehicle is experiencing a simple "burn out" at each tire. That's all. The suspension, steering gear, wheel bearings … all experience the same loads as power oversteer on one side and braking understeer on the other side.

It's not that the R1 needs all its power and torque to break traction at one or more corners ... even on asphalt.

The thing that Rivian really needs to do is finish the software to balance these two moments and keep the vehicle spinning within its wheelbase. Then, all they need is a "call my mommy" warning on the touchscreen.

Sigh.... watch the video. I'm using the word "sideways" to simplify the explanation of lateral forces on the tires and therefore the suspension due to the vehicle rotating about its center. It's not a simple linear burnout. The vehicle's mass is rotating about the centerpoint and therefore the front and rear are moving "sideways" and therefore applying lateral pressure to the tires and suspension.

Yes, in physics terms, it is a moment - The force exerted to make an object rotate about a point. Third law of physics says that for every force, there is an equal and opposite reaction. For the vehicle to rotate about its center, energy via the tires and suspension must be transferred in the opposite direction to spin the mass of the vehicle around its center point. Cheers, I'm signing out of the discussion.

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[totmafang]

I think Rivian's outstanding preorder/reservation count may be a bit specious. I suspect internally they are seeing concerning numbers around conversions to actual orders, particularly for post-price-increase reservations in light of the macroeconomic environment and changes to the tax credit. Consider new orders placed today are estimated to deliver as early as "late 2023." If true that's really not much of a wait for a product that has over 100k reservations. I don't think they're ramping the line quite that fast.

I am with you. In fact, after I saw the huge price drop from Tesla and Lucid $7500 lease discount yesterday, I feel that there's a tremendous price pressure on Rivian's new pricing. There might be more EV price drops from other manufacturers very soon (to compete with Tesla). I wonder how many of these post-march pre-orders are gonna actually turn into actual sales if there're more other good EV options (not saying any of them is in the same category or as good as Rivian, but maybe more affordable but also good enough like Ioniq 7?). What if Tesla announces the new price for Cybertruck's tri-motor version to be $79,900 (qualify for federal tax credit)? Personally, I really don't like the Cybertruck design, but there're over 1.3 million cybertruck pre-orders which probably covers a lot of EV buyers who will have to decide on only one or two of their pre-orders. I suspect Rivian is gonna have to follow with some price drop to be competitive. Only time will tell, but I wouldn't want to pay potentially 10~20% higher now than a few months later.

 

[quartz]

If I was to guess at reasons why Rivian hasn't delivered tank turn mode, there's (1) they're lacking a gyro or other sensor with sufficient resolution to solve for all potentials and (2) legal beagle fear of negative PR resulting from abuse (e.g. death, injury, public nuisance.) I recall someone at Rivian mentioning it wasn't their brand image to be spinning donuts, ripping up the ground instead of "treading lightly" (which is patent nonsense, but could well become the lip service they use to excuse themselves.)

In order to do a successful tank turn (like in the ad video) you have to be on flat, slippery ground. You have to assume some people are going to try to pull a tank turn on a slope while rock crawling to get into a better position, which is obviously a major hazard since the rotational force required will be much, much greater than under ideal conditions. Loads of power and no control. It’s 100% a safety issue.

 

[Thedude]

I don't mean to bore you or the readers of this thread, but the tires are not moving and cannot move "sideways" … tires only roll or slip.

'The vehicle is not moving sideways, either, it's rotating on an axis:
1. Two tires rotating forwards, experiencing the loads of a standing start launch like a 0-60 drag.
2. Two tires rotating backwards, experiencing the loads of heavy braking.

I'm no physicist, but I'd call these moments.

It's a four wheel drift, with one side of the vehicle is drifting forwards and the other side drifting backwards. Rotating around a vertical axis or polar center.

The vehicle is experiencing a simple "burn out" at each tire. That's all. The suspension, steering gear, wheel bearings … all experience the same loads as power oversteer on one side and braking understeer on the other side.

It's not that the R1 needs all its power and torque to break traction at one or more corners ... even on asphalt.

The thing that Rivian really needs to do is finish the software to balance these two moments and keep the vehicle spinning within its wheelbase. Then, all they need is a "call my mommy" warning on the touchscreen.

The tires are spinning, yes, but the lateral force on it is completely different than from what it experiences in normal forward or rearward driving. Even towing trailer down a mountain doesn’t compare.

 

[Swilly]

Want an R1 soon? Live near a SC. It's not that hard to figure out at this point

R1S Jan 2021 reservation here. 15 miles from Denver SC. 2024 delivery estimate. So…how close do I need to be to a service center for delivery to happen sooner?

 

[SeaGeo]

R1S Jan 2021 reservation here. 15 miles from Denver SC. 2024 delivery estimate. So…how close do I need to be to a service center for delivery to happen sooner?

So functionally the same as late 2023.

Mine is May 2021 and q3 2023. The Denver allocation and where you slot into it apparently has you further back. ?‍

 

[Swilly]

So functionally the same as late 2023.

Mine is May 2021 and q3 2023. The Denver allocation and where you slot into it apparently has you further back. ?‍

My only point is that proximity to SC is not the only factor delaying some orders. Even factoring heavy early ordering in Denver, review of other orders on the tracking threads on this forum show I am significantly (6+months) outside the average for delivery date based on order date and specific build.

 

[SeaGeo]

My only point is that proximity to SC is not the only factor delaying some orders. Even factoring heavy early ordering in Denver, review of other orders on the tracking threads on this forum show I am significantly (6+months) outside the average for delivery date based on order date and specific build.

Yeah, I wasn't saying it was the only one, but being far from one is about as sure fire of a way to either have a late estimate or not getting one as anything.

 

[DB-EV]

Not quite what I was implying. You made a lot of references to my order but I made no mention of my order. Just the general fact that companies operate for purposes of profit and they tend to seek the most of it however they can. No one really knows precisely who's gets produced first. If you change color or wheels in config, that gives them an 'excuse' to throw you back into the line -- I get that, but how far back in line? a week, a month, a quarter, a year?. Its so purposely vague.

Needless to say, I haven't touched my order since they started warning about midnight deadlines to lock in your config. But still says Processing estimate.

I think they have an economic incentive to delay R1s's some.

They prioritized T to hit 2022 numbers but I do think they want to get S's out. I could be totally wrong.

 

[the long way downunder]

The tires are spinning, yes, but the lateral force on it is completely different than from what it experiences in normal forward or rearward driving. Even towing trailer down a mountain doesn’t compare.

You think that a tire that has lost traction can exert more force than a tire that is maintaining traction?

 

[Swilly]

Yeah, I wasn't saying it was the only one, but being far from one is about as sure fire of a way to either have a late estimate or not getting one as anything.

Mostly true. I have seen a few that are way outside SC area and got delivery, outside the YouTuber crowd that get them regardless of location.

 

[the long way downunder]

In order to do a successful tank turn (like in the ad video) you have to be on flat, slippery ground. You have to assume some people are going to try to pull a tank turn on a slope while rock crawling to get into a better position, which is obviously a major hazard since the rotational force required will be much, much greater than under ideal conditions. Loads of power and no control. It’s 100% a safety issue.

Well, the Rivian tank turn video shows an R1T making a tank turn on a trail on a hillside.
As far as surface slip, gravity, gradient … the sensors and the software would have to be make adjustments and detect any shift in the center of rotation quickly enough to compensate for even an inch or two of drift. Safety is always an issue, but in this case, not an obstacle. There's always the safety of the system just quitting and locking up all four brakes (or the user touching the brake.)

I assume the user would have steering and throttle input, but an early, simplified arrangement could require the vehicle to be at a complete halt on a grade that the system detects and accepts as viable with no obstacles on the radar or ultrasonics at any time during the maneuver.

The user could be required to have the steering wheel in the straight ahead position and Driver+ could hold the steering in the straight-ahead with no pedal input.

The user operates tank turn through the touchscreen and varies the rate of turn with the accelerator, choosing left or right rotation to start the turn from the touchscreen or perhaps steering wheel controls (e.g. R for left and D for right.)

If the user attempted steering input or brakes (or any safety event like lifting off the seat, releasing the seat belt or any door or even any window was actuated) the turn would stop with all four wheels braked till the driver took over.

After a few iterations, tank turn could happen while the vehicle is in motion, steering could be off-center, braking could drift the vehicle more rearward, more accelerator input could drift the rotation more forward (forward and rearward would be rotating 360 degrees continuously, so the effect would be spiraling in a direction while rotating around the vehicle's center.)

An advanced form of tank turn becomes what we see in rally driving (RIP Ken Block, you are missed) and drifting.

p.s. For those still questioning the mechanical forces of tank turn, watch some videos of factory stock vehicles used in road rally, off-road rally and drifting … factory stock road cars with unimproved suspension, wheel carriers, and bushings … strong enough to perform four wheel drifts without mechanical failure.

 

[Thedude]

You think that a tire that has lost traction can exert more force than a tire that is maintaining traction?

I think you don’t understand basic physics. The tire isn’t just spinning in place, it is being pushed sideways in an arc applying forces perpendicular to the normal axis.

 

[the long way downunder]

I think you don’t understand basic physics. The tire isn’t just spinning in place, it is being pushed sideways in an arc applying forces perpendicular to the normal axis.

I don't purport to be a physicist or engineer; do you?

For some reason, there are people who see a tank turn but can't see oversteer or braking, slip angles, steering scrub, etc.

Perhaps Max Hoff will post to this thread and share the calcs and algos used to develop tank mode.

 

[Mathme]

I think Rivian said not too long ago that Order date, SC proximity, Config availability are important factors in delivery timeline. I recall several threads of people being upset at Rivian for not paying for transportation to a SC when they are 4+ hours away...and those same people not wanting to pay for the transportation.

I also think the R1 Shop was a good idea as they have a surplus in some interior/exterior color choices. For me, I'm thinking about 3 exterior dolor choices and two interior. If my config were available in a secondary choice, I'd likely jump at it. Points to Rivian to for coming up with a low-cost (to them) way of letting people naturally select alternatives.

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