Dual Motor CT is estimated at 690 horsepower and 824 lb-ft torque

[Humanoid1]

If it has the sensors for full self driving, it should be pretty easy to keep it from accelerating into objects up front. However, I hope the safety features don't prevent us from driving through brush and branches on barely maintained logging roads.

Tesla safety feature can be switched off, all of them as far as I am aware, turning it into a regular car from that point of view.
Feel free to correct me, I do not currently have access to one to test.

I have certainly seen a few pictures of Teslas smashed into the walls in car parks where someone stomped on the wrong pedal.

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[Ehninger1212]

Tesla has "chill" mode which makes the vehicle significantly slower.. you can turn that on if the acceleration is to much for you babies.

 

[ajdelange]

Thanks for your response, I would love to give a proper reply now but have to prepare for a big shopping mission for a couple of families.
I might remind you though that although electric motors have peak torque at 0 rpm, their peak efficiency if often at a much higher rpm, perhaps at say 90% of its rated rpm.

Well yes, that's true. Obviously a great deal of effort goes into designing the motors such that they are most efficient at the speeds around which the car normally cruises as this translates into minimum Wh/mi and thus maximum range under typical use conditions. And it goes without saying that if you lock the rotor and apply current the efficiency will be 0 as current will be drawn and heat generated but no mechanical power will be produced. But that doesn't happen in a BEV as the controller will sense the locked rotor and shut off the current.

The picture you post may represent a typical PMDC motor but it does not represent the motors that are going into BEV these days. Tesla is currently using induction and switched reluctance motors with permanent magnets. It is also worth noting that we now have vector field control of these motors which makes them much more efficient than they used to be. As you can see from the picture I posted (measurements from a modern PMSM motor) efficiency is best at midrange speed and torque but is still pretty good in the startup range. Do keep in mind that there is a fair amount of reduction gearing in the transmissions of these cars. Looking at the plot suppose that the gearing and tire radius were chosen such that engine speed were 6000 rpm at 60 mph (reasonable and makes the math easy). Then at a 1 mph crawl the engine speed would be 100 rpm. That's at the left edge of the plot and efficiencies are from 51% (the lowest number on the chart) to over 90% depending on the torque requirement. So yes, you are right in that the motors are less efficient in a crawl than at cruise on the highway but not by nearly so much as you seem to think. And, as I showed in my last post, it doesn't matter.

Tesla is, of course, aware of all this. If they thought lower gearing were necessary they would design the car with lower gearing.

Our legs are a little like an electric motor in this regard and we all know how much easier going up a steep hill is in a lower gear with higher rpm while riding a bicycle.

It isn't any easier at all. The same amount of work has to be done. If I weigh 100 kg (and, to my disgrace, I do) I must produce 980 joules of energy for each meter my altitude increases whether I am pedalling furiously fast in a low gear or trying to generate more torque than I can in a low gear. I cannot apply more than 980 N to the pedal.

 

[SSonnentag]

Thanks for your response, I would love to give a proper reply now but have to prepare for a big shopping mission for a couple of families.
I might remind you though that although electric motors have peak torque at 0 rpm, their peak efficiency if often at a much higher rpm, perhaps at say 90% of its rated rpm.

Our legs are a little like an electric motor in this regard and we all know how much easier going up a steep hill is in a lower gear with higher rpm while riding a bicycle.

I will enjoy getting deeper into the numbers with you later. Have a great day

Does this mean that gearing lower, which would lower the top speed, to something like 100 mph, could significantly improve the highway efficiency of the CyberTruck? I may have inadvertently exceeded 110 units per hour when passing someone a few times in my Model S, but could certainly give up 30 mph of top speed in exchange for greater highway efficiency.

Edit: After seeing AJ's diagram, all the above seems moot, assuming its correct. It sounds plausible though.

 

[ajdelange]

If the motors used in BEVs had characteristics that even remotely resembled the diagram posted by Humanoid1 then the designs of the cars would be very much different than what they in fact are. There would be elaborate gears/automatic transmissions to try to keep motor speed near 85% during cruise whether that be at 45% or 90 mph. Different gears would be selected to get you to high torque for acceleration but you would pay a heavy penalty for this as you couldn't have maximum torque except at very low efficiency. So I say again. Those curves are not typical of BEV motors. The picture I posted is typical of BEV motors. Note that this motor exhibits constant maximum torque out to about 3700 rpm at efficiency always greater than 51% and more or less constant power output (product of torque and rpm) at higher speeds with a large area (large span of torque and rpm) available at efficiency > 90%. This is what you want and need for a BEV motor. I have no idea what sort of a load the motor depicted in Humanoid1's curve was designed for but it clearly wasn't for use in a BEV.

 

[Hunter Sawyer]

Although Cybertruck clearly has the power/torque to make it's relatively high gear ratio work great for day to day driving just like works so well in the rest of the range, it does not work so well for low speed off roading up a steep rough track. It can do it well (will certainly make it up), but it is inefficient and sucks a lot of power. A possible crawler gear would make it more efficient in these scenarios as well as more controllable while the truck is bounced around over big rocks etc
I am hoping that the Cybertruck is the first Tesla with more than one gear.
What do you guys think?

Youtube channel The Fast Lane Car took a Model X offroad and noted the higher than expected power drain. Being a Model X it was a fairly tame uphill but still consumed an avg 1546wh per mile!

Technically the early roadsters were the first Tesla's to have a gearbox.

 

[ajdelange]

They were also the first to have a steering wheel.

The gearbox on the roadster was a single speed BorgWarner fixed gear (8.27:1 ratio)

 

[TyPope]

Tesla needs to offer a lower HP “valet” option that you can lock out via the touch screen. Dodge offered this option on the limited edition Dodge Demon.

Valet mode is a thing with the current models. It locks out top speed and lowers acceleration level and keeps the Frunk and glovebox locked.

 

[ajdelange]

Just noticed that the curves posted in No. 30 are for a PMDC (Permanent Magnet DC) motor. The difference between these (typically used for the fans in computers) is that they have Y connected 3 phase windings in which the battery + is connected to A and - to B and C for a bit and then + goes to B and C and A go to - for a period and then C goes to + and A and B to -. This creates a magnetic field which goes around the motor in steps. In a PM synchronous motor, by contrast, the switching is done at a much higher rate (10's of kHz) and the pulses are of variable width (PWM = Pulse Width Modulation) thus causing the voltages sent to the three phases to closely approximate sine waves (vs square waves in the PMDC motor). This results in a smoothly and uniformly rotating magnetic field. The PWM allows the currents in the windings to be adjusted such that motor flux and torque can be separately controlled. This is why the induction and switched reluctance motors in the Teslas have such good efficiency.

 

[Alpeyev]

690 horses, damn that is insane. That's scary close to the Challenger Hellcat at 707, and that's an american MUSCLE car. So you mean to tell me this thing is gonna lay you into the back of the seat like a HELLCAT??? Beyond cool, this is a whole new level of badassness.

Yes, and it will be at any speed. You just slam accelerator and feel that g force. Just like other Tesla’s. Some of you guys have not had an opportunity to drive Tesla. It is exhilarating and gets the giggles out of grown man.

 

[Mini2nut]

I had the opportunity to drive a Model S 100D for a long weekend. Wow, you guys and gals are going to be blown away by the instant torque of a Dual Motor Tesla vehicle. You are in for a real treat and will probably never own an ICE vehicle again.

Getting back to Into my ICE vehicle after spending the weekend in a 100D was a huge disappointment. Hearing the starter motor cranking, engine noise, exhaust noise and emissions coming out of the tail pipe, etc. I am now convinced that BEV’s are the future for the automobile.

 

[Edisonsucks]

I had the opportunity to drive a Model S 100D for a long weekend. Wow, you guys and gals are going to be blown away by the instant torque of a Dual Motor Tesla vehicle. You are in for a real treat and will probably never own an ICE vehicle again.

Getting back to Into my ICE vehicle after spending the weekend in a 100D was a huge disappointment. Hearing the starter motor cranking, engine noise, exhaust noise and emissions coming out of the tail pipe, etc. I am now convinced that BEV’s are the future for the automobile.

I test drove the base model 3 and drove some coworkers around while I had it. Everyone was smiling and laughing. Can’t imagine the performance or higher models acceleration.

 

[SpaceDoc]

^^^ THIS ^^^

I think you will find most pickup truck buyers don't by for speed, but for hauling capacity, towing capacity, and utility.

i live in Houston, Texas and there is no shortage of jacked up pickup trucks hauling ass down the freeway here. They cut in, and weave in and out, to get ahead. ride up on your tail. it can get pretty annoying.
Doesn't happen so much on surface streets fortunately.

 

[Cebliminal]

Tesla has "chill" mode which makes the vehicle significantly slower.. you can turn that on if the acceleration is to much for you babies.

I want to hit the pedal and take off like a rocket if I choose too, a few of you want an old school governor. I’m buying this CT BECAUSE OF THE POWER or else I would buy the weak ass telluride

 

[ajdelange]

...a few of you want an old school governor.

A hillbilly farmer name Hollis
Used possums and snakes for his solace
The children had scales
And prehensile tails
And voted for governor Wallace