SPECIAL EDITION QUAD-MOTOR Cybertruck rumor

[CappyJax]

Sure, in the real world it is hard to sense slight altitude changes.
The real world example given here were for round trip over the same roads so any change would mostly be canceled out.

But you make assumptions when you did the Cybertruck towing 14,000 lbs will be 2,000 wh/mi
You did not inform the forum readers of all these caveats then.

What are all the assumptions you used?



More ad hominem attacks.

I could make similar attacks but I will let facts & science do the work.

You made all these assumptions when you used this supposedly fancy spreadsheet to do an estimate for the Cybertruck but now you say it is too difficult to make reasonable assumptions for real world examples that all forum readers have access too.

I guess forum readers should infer that the assumptions you used for the Cybertruck were not reasonable.



I am not disputing there will be some variances but you are the one that now throws out that there are all types of mitigating factors when your original 2,000 wh/mi answer did not mention any of them.

Your Cybertruck towing 14,000 2,000 wh/mi estimate is worthless since your spreadsheet does not give results close to typical real world trips without vetted & validated spreadsheet.

assumptions to use with Cybertruck towing 14,000lbs and other real world examples
steady speed 55 mph
altitude: sea level
level U.S. highway with normal speeds of 55-80mph (no hills, no mountains)
no stop & go traffic
no wind
moderate temp 70F

Are they other types of materially significant assumptions you made with Cybertruck towing 14,000 lbs 2,000 wh/ni estimate but did not tell us.

Here are some real world examples that would tell us about reliability of the spreadsheet

real world example 2
Tesla Model X LR+, 100 kwh, 5,421 lb (2,459 kg), 350 miles range
2018 Airsteam Bambi 22', 4,500lbs, 55mph, 489 wh/mi

real world example example 3
1. total weight: 11,000 lbs ( 4,990 kg )
--- (tow vehicle, 2 people (400lbs), bags (400lbs), misc stuff (120 lbs), trailer ( 6,000lbs)
2. Coefficient of drag for tow vehicle: 0.25
3. Coefficient of drag for trailer: 0.55
4. area of front of tow vehicle: 25 square ft ( 2.31 sq meters )
5. area of front of trailer: 76.5 sq ft ( 7.124 sq meters = 2.60m x 2.74m)
6. speed: 56 mph ( 90 k/h )

real world example 4
2017 Ford F-350 Gross weight 9900 lbs 15-17 mpg, 8-10 mpg towing ( 50% loss when towing)
2019 Grand Design Reflection 312BHTS 37ft GVWR 11,295 trailer
Height 11' 8" ( 3,556 mm )
Width 8' ( 2,438 mm )

I suspect you will not give us answers to these real world examples because the answer would show your spreadsheet does not work.

A spreadsheet that does not provide entire source so it can be vetted and is not validated against real work examples is worthless.

I am done arguing with you. You can educate yourself if you want, or you can just keep playing the fanboi. You can't change physics with wishful thinking.

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[ericpdb2]

There are sound rumors from Tesla workers about a possible Quad-Motor Super Performance Cybertruck model capable of insane maneuvers. Anyone have any thoughts?

IF Quad motor makes the CT faster and increases the range I will gladly pay the incremental cost over the Tri Motor I have reserved. It is excessive. I welcome more excess. I am old and scrimped for decades to have fun in retirement. I WANT a 4 motor CT with rockets. NOW.

 

[Youaregoldone]

I am not your technical support.

Guys..Guys!...Aren't we here to make constructive comments for our upcoming awesome vehicle? If you wanna get into a Cyber-Fight, go to social media! Here are welcomed only CT's brothers & Sisters.

 

[CappyJax]

Guys..Guys!...Aren't we here to make constructive comments for our upcoming awesome vehicle? If you wanna get into a Cyber-Fight, go to social media! Here are welcomed only CT's brothers & Sisters.

This thread has been dead for over a week. Why are you trying to stir shit up?

 

[Youaregoldone]

This thread has been dead for over a week. Why are you trying to stir shit up?

I just saw that...The only thing I like to stir is gravy, bro.

 

[texhood]

There are several proposed schemes for gooseneck attachment to the CT.

The reason for moving the attachment point forward in a trailer hookup is a matter of torque in two planes. In the vertical plane if the weight is behind the rear wheels the torque "transfers" weight away from the front wheels with obvious implications to steering. In the horizontal plane a lateral force on a trailer attached behind the rear whells applies a torque about them thus rotating the vehicle which can lead to sway and instability. Traditionally these torques are compensated for by weight transfer schemes, fifth wheel and pivot point projection hitches. In the TriMotor CT the sway torque can largely be neutralized by rear wheel torque vectoring. That doesn't mean that fifthwheel/gooseneck attachment isn't desirable.

But the subject of this thread is a 4th motor up front. This isn't going to help with sway reduction or weight transfer. Thus I don't see (though I readily admit I could be missing something) any advantage to a 4th motor for towing. In fact I'm not sure I see much advantage to it for anything but marketing and, as an engineer, I confess a strong attraction to the concept in terms of "cool" factor.

Here on the ranch, most of our towing is done with gooseneck trailers. It is difficult to find a cattle trailer anymore that is not a gooseneck.

 

[rr6013]

Here on the ranch, most of our towing is done with gooseneck trailers. It is difficult to find a cattle trailer anymore that is not a gooseneck.

tl:dr
Late to this thread, piling on. Cybertruck is limited to amount of rear loading specified as “dead weight”. Extensive testing on Jeeps puts this rear weight behind the axel limit at 200#. A shortbrd pickup 110” wheelbase limit at 220#. CT’s stiffer exoskeleton will carry weight distribution to all four wheels but end loads act differently. CT will very efficiently transfer end load force forward with rear axel acting as fulcrum lifting the front wheels off the ground.

This from T-6 alum tests to carry load behind axel at the frame.

http://appft.uspto.gov/netacgi/nph-...71".PGNR.&OS=DN/20050199671&RS=DN/20050199671

 

[ajdelange]

CT will very efficiently transfer end load force forward with rear axel acting as fulcrum lifting the front wheels off the ground.

The end of this sentence contradicts the start. The stiffer the frame the more effective it is at removing weight from the front wheels if there is a moment. Thus the fifth wheel and derivative hitches. They put the tongue weight over the axle. No moment.

 

[SpaceDoc]

...

There really is less and less need for 4x4. It is a vestige of ICE to think in terms of a motor at every wheel. ...

Seems like you got something against 4x4. LOL!

What you are describing is your personal preference. There are plenty of folks that want or need 4x4 for whatever reason, for camping, recreational off roading, working in remote locations, lots of snow driving, etc. Or they want that capability for emergencies or occasional use.

Also, a lot of it is an age thing. When I was younger I'd off-road a lot, now not so much. And also a where you live thing. I used to live in various Rocky Mountain states, where 4x4 is fun to have, now I live in coastal Texas, which is mostly flat (though lots of mud if you're off the pavement).

And I'm not sure what the "motor at every wheel" thing is about. ICE 4x4s don't have that, and it's not required for EVs to have that capability. Anyhow, my two bits on that.

 

[rr6013]

Seems like you got something against 4x4. LOL!

My 4x4 experience harkens back to M-37, ‘46 Power wagon to Jeep Rubicon and a smattering of straight axel four wheel drive in between featuring ‘knuckles, posi-trak, portals and liquid viscous that covers a few variations. Some in mud so damn deep, all that worked was chaining-up the fronts and letting them pull through the muck.

Suzuki brought its 2cycle Brute 4x4 to America early 70’s. That cost me a bet as all my heavy machinery proved heavy conditions required real trucks with real 4x4. Suzuki Brute had 4x4 but only 66” wide, <1600# and a ridiculous motorcycle tiny motor. I confidently took that bet that it could not go where all the above dared. It soundly whooped my bet.

Suburu has doubled down on lightweight using AWD embarrassing 4x4 owners handily. In America most backcountry is inaccessible, locked up. What conditions demanded 4x4, asphalt with the advancement of time has obviated the need. Niche corner cases remain just that.

Today 4x4 owners must drive out of their way to find situations, conditions and places that 4x4 can get them unstuck. Snow and mud are last great examples where RWD sucks and AWD sucks less. Some manufacturers AWD beat 4x4.

BUT putting portal motors at all four corners in a quad-motor electric version of 4x4 is nonsense for all but 1/1000th use cases. Those being heavy tired chained-up pulling through mud and rockcrawling high torque vectoring happening.

The understanding of 4x4 comes through exposure, experience and knowing that just putting power at every wheel just buys broken components as torque moves away from your points of heaviest power transfer. There’s reason to Tesla inserting a heavy open differential between Plaid dual RWD motors. No secret that it uses just one motor at front driving two wheels through differential. Power transfer reliability.

 

[FullyGrounded]

I guess I'm resurrecting the all but dead. But, this is some real input. I actually think, that if you put it to the people, what do they want a super fast, capable Cybertruck with 4 motors, one at each wheel; or 1,000 mile range - most would choose the 1,000 mile range. simple

 

[CyberMoose]

I guess I'm resurrecting the all but dead. But, this is some real input. I actually think, that if you put it to the people, what do they want a super fast, capable Cybertruck with 4 motors, one at each wheel; or 1,000 mile range - most would choose the 1,000 mile range. simple

Personally I really hope there is no quad motor Cybertruck coming out. I see no reason for the Cybertruck to go any faster, the towing capacity is already amazing and the patent pictures hinted at possibly 20000, the range is at a pretty ideal spot, however if they release a quad motor, I would probably switch despite knowing it's probably not worth it. Then I would have to explain to my wife why i upgraded, which would be basically no reason, and she would probably let me because I never really buy myself anything nice. Tesla needs to be the responsible adult in my relationship and keep me from buying the quad motor by not making one.

 

[FutureBoy]

I guess I'm resurrecting the all but dead. But, this is some real input. I actually think, that if you put it to the people, what do they want a super fast, capable Cybertruck with 4 motors, one at each wheel; or 1,000 mile range - most would choose the 1,000 mile range. simple

Well, that probably depends on what else is in the trade. Other than the cool idea of having 4 motors, there is no reason to have 4 if there is no further benefit beyond 3 or even 2.
I am previously on record as wishing 1000+ miles of range. My desire for that range though has everythingto do with going seriously off road and with towing large campers (possibly with these 2 scenarios combined).
Now if the 4 motors somehow benefit the 1000 mile range scenario, then they would be desirable. If they don’t add much beyond a Rivian tank turn then give me the range instead of 4 motors. If the 4 motors upgrade from a comparable F250 to an F350 but in the same overall CT footprint, then 4 motors get real sexy.
But if 4 motors gets me only a badge on the vehicle, it’s not worth it.

 

[Revoltlution]

There's a smattering of torsen diffs out there that put a smackdown in 4x4 performance. Hoping for some elon news that they'll be using torsen, but #bestpartisnopart and the minimal times one need true limited slip, a high speed algorithm brake check should do the trick.
Shout-out to design prototype test

 

[ajdelange]

The understanding of 4x4 comes through exposure, experience and knowing that just putting power at every wheel just buys broken components as torque moves away from your points of heaviest power transfer.

Power is simply torque times shaft speed. Power is transferred to the shaft from the motor and thence through the tire to the substrate. Thus putting the motor at or even in the wheel gets the power transfer and torque closer together - not farther apart.

There’s reason to Tesla inserting a heavy open differential between Plaid dual RWD motors.

There would be no reason to do this nor can I even think of how it might be done. A differential has three shafts. Where would the third shaft connect in such an arrangement?

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