Tesla Wall Connector (Gen 4) for Cybertruck

[Crissa]

A self propelled trailer would be catastrophic in emergency situations. What does make sense is a trailer that stores energy via regen instead of only relying on friction brakes. Then you have stored energy for camping or recharging XYZ truck batteries.

That's literally a self propelled trailer, tho.

-Crissa

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[SolarWizard]

That's literally a self propelled trailer, tho.

-Crissa

that is not propelled. Its exchanging brake dust for recouped energy. A propelled trailer would provide drive.
Aka there is no motor, just regen brakes

 

[SolarWizard]

No it wouldn't. The trailer would be programmed to accelerate when the accelerator is pressed, coast when coasting and brake when braking. A couple companies are already coming out with these. If the trailer has momentum whether it created it by itself or if the momentum was created by the tow vehicle it would have the same amount of momentum in an emergency situation.

tell me more about the trailer brake wiring delivering throttle input signals from the drive computer. Then tell me more about some mythical standard that calculates and delivers more data about yaw, trailer angle, road surface & real time traction data.
There are exactly zero trucks and have never been more than zero trucks that do this. Never.

 

[Ogre]

We already know the Cybertruck will be super-efficient for its size and capabilities. That's Tesla's expertise and focus because it's what makes long-range EV's economically practical. It sounds like you were hoping the Cybertruck would be inefficient and have a huge battery so the hit from towing a large trailer would be a smaller percentage hit. That's not how this will turn out to be. Tesla is all about making their vehicles as efficient as possible because that saves their customers money on the size of the battery for the amount of actual range provided.

As you know, for a given size battery, it doesn't hurt towing range to make the truck more efficient, it helps it.

You see determined to argue with me here. I don’t hope anything of the sort. Just pointed a fact out which you don’t even dispute.

I hope you are 100% correct. I’m a little less convinced it’ll be quite that efficient, but I’m not in love with any particular numbers. At one point in time I dug into it a bit more and came up with 185 kWh being a realistic minimum, but there is just too much we don’t know to really pin any specifics down. I plug in 200 kWh mostly to get conservative price/ weight guesses. Any optimization below that is gravy.

 

[Ogre]

that is not propelled. Its exchanging brake dust for recouped energy. A propelled trailer would provide drive.
Aka there is no motor, just regen brakes

I don’t quite get the point in having regen if you don’t have a way to spend the energy while driving. You will quickly fill the cell to capacity and then you just have a heavier trailer following you. Ideally, the driving vehicle communicates to the trailer when to apply acceleration. Second to that would be having a way for the trailer to provide power to the driving vehicle via a charge cable.

But just regenerating with no output isn’t going to save your brakes much. Once it fills the cell, you are dragging around extra hardware to no point.

 

[anionic1]

tell me more about the trailer brake wiring delivering throttle input signals from the drive computer. Then tell me more about some mythical standard that calculates and delivers more data about yaw, trailer angle, road surface & real time traction data.
There are exactly zero trucks and have never been more than zero trucks that do this. Never.

You should go back to my original statement. It's in the near future. "we will see". Airstream is coming out with a self propelled trailer link. Most trailer braking uses a caliper mounted to the hitch so that the car doesn't need a feed to the tow vehicle. With current braking tech the trailer can tell when the car is braking by inertia and it also brakes. They could probably do something similar for accelerating. It also doesn't seem very difficult to put sensors on the brake and accelerator that talk to the trailer.

 

[Crissa]

that is not propelled. Its exchanging brake dust for recouped energy. A propelled trailer would provide drive.
Aka there is no motor, just regen brakes

There is no device that does that.

-Crissa

 

[ldjessee]

Simply put, regen braking is done by exchanging rotational motion in a motor to have that motor act as a generator.

The interacting magnetic fields slows down the vehicle, thus 'braking'.

 

[Crissa]

Simply put, regen braking is done by exchanging rotational motion in a motor to have that motor act as a generator.

The interacting magnetic fields slows down the vehicle, thus 'braking'.

And any motor capable of absorbing that energy can also be used propulsively. There is no way to build a motor capable of regen and not drive unless you specifically lock it out via software.

-Crissa

 

[HaulingAss]

You see determined to argue with me here. I don’t hope anything of the sort. Just pointed a fact out which you don’t even dispute.

I hope you are 100% correct. I’m a little less convinced it’ll be quite that efficient, but I’m not in love with any particular numbers. At one point in time I dug into it a bit more and came up with 185 kWh being a realistic minimum, but there is just too much we don’t know to really pin any specifics down. I plug in 200 kWh mostly to get conservative price/ weight guesses. Any optimization below that is gravy.

I'm not in love with any specific numbers either, as you point out, it's a guessing game. I'm just saying, given the known specs of the 500 mile Tri-motor, there's no reason for it to be bigger than 200 kWh. If I had to guess a specific number, I would guess your 185 kWh number is as good as any, maybe 190 kWh. 225 kWh guess is kind of in left field with nothing to support it. That's all I was trying to say.

All will be revealed on a "need to know" basis, LOL!

 

[Ogre]

I'm not in love with any specific numbers either, as you point out, it's a guessing game. I'm just saying, given the known specs, there's no reason for it to be bigger than 200 kWh. If I had to guess a specific number for the 500 mile Tri-motor I would guess your 185 kWh number is as good as any, maybe 190 kWh. 225 kWh guess is kind of in left field with nothing to support it.

All will be revealed on a "need to know" basis, LOL!

Funny thing is we’re likely not going to know battery size either until after launch and people have a chance to charge them up.

 

[HaulingAss]

And any motor capable of absorbing that energy can also be used propulsively. There is no way to build a motor capable of regen and not drive unless you specifically lock it out via software.

-Crissa

True. Also, a trailer with independent motors left and right and some pretty basic sensors could follow another vehicle perfectly and could even have active "trailer sway" control built into the drive software such that it was impossible for the trailer to jackknife.

The batteries, motors, inverters and software are the only parts that substantially raise the price. But towing long distances is not exactly a huge market in terms of spreading the costs of the software development over enough units sold to make it worthwhile, especially considering that the price of the batteries and motors will shrink the market further.

Towing large trailers over long distances (not semi-tractor scale) is a niche activity that is only as popular as it is because of historically cheap gas and diesel. When the price of fuel rises, recreational towing miles shrink rather dramatically. Making the trailer that much more expensive with batteries, motors and software development, would have a similar chilling effect on the number of people who towed large trailers over long distances.

 

[HaulingAss]

Funny thing is we’re likely not going to know battery size either until after launch and people have a chance to charge them up.

We will get a very close, much closer, idea of battery size when we know the EPA range and the EPA consumption figures.

 

[Ogre]

We will get a very close, much closer, idea of battery size when we know the EPA range and the EPA consumption figures.

Forgot about that. But doesn’t that come pretty close to when deliveries start? Trying to remember when we saw the Model Y numbers.

The other really interesting numbers we definitely won’t see until after launch and thats actual charging times.

 

[charliemagpie]

Towing large trailers over long distances (not semi-tractor scale) is a niche activity that is only as popular as it is because of historically cheap gas and diesel. When the price of fuel rises, recreational towing miles shrink rather dramatically. Making the trailer that much more expensive with batteries, motors and software development, would have a similar chilling effect on the number of people who towed large trailers over long distances.

got me thinking.

Given its specs, the CT should be the goto truck for all RV owners who are pulling 3+ ton Rv's.

I'm not an expert, but came across a vid a few months back, and the basic premise was trucks are advertised at towing say 3.5 tons, but in reality, they fail other metrics such as GVM.. gross vehicle mass. Insurance will not cover.

like the old motto ' nobody ever got fired for buying IBM', buying a CT will keep you legal.

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