“Crawl Control” for the Cybertruck?

[parapyropig]

Predicated on my most ernest hopes that the TCT will be trail worthy enough to take into the Colorado mountains, it would be most useful to have crawl control, like with the newer Toyota 4 x 4‘s.

For the uninitiated, this feature essentially replaces the need to learn how to do left-footed braking when negotiating larger rocks and other obstacles that have a sudden drop off (this would keep the vehicle from lurching and bouncing over obstacles).

I would presume this would be merely software that could be controlled from the user interface, rather than using dial & knobs as with the Toyotas.

And, if not, one could always resort to good old-fashioned left-footed braking.

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[ajdelange]

As about 85% of those who responded to a poll here have no EV experience I am going to assume that you are not familiar with regenerative braking. With it enabled an EV brakes the instant one relaxes pressure on the accelerator or removes his foot from it. With the motors used in these cars it is possible to apply torque to the wheels in either direction be they rotating forward or reverse. You are right that this is managed by the inverter/motor control software and thus what can be done is virtually unlimited. The control wanted for crawl would be much more dramatic than that needed for normal regen but the principles are the same and IMO it is quite doable. That, of course, does not mean Tesla will implement it so send a message to Elon and suggest it.

 

[Saskateam]

Crawling means real slow. Like under 2 m/hr. The regene would be off by this point and would need a different setup to apply the friction brakes. It would be nice to have the brakes allow a little slip to slowly lower off of an obstacle.
I am also concerned about throttle control when crawling because there is not a low gear ratio. I hope the CT comes with a complete off road setting.

 

[ajdelange]

Crawling means real slow. Like under 2 m/hr. The regene would be off by this point and would need a different setup to apply the friction brakes.

Not a problem. As I said in #3 it is possible to apply nearly full torque in either direction at 0 and near 0 wheel speed in either direction. The friction brake would not be needed but one would probably want to get it on as applying torque at 0 speed through the electric motors uses battery even though the vehicle is not moving. The Rivian has an advantage here in that torque can be separately controlled at each of the 4 wheels whereas that can only be done at the rear wheels (I assume that's where the two motors go) of the CT.

It would be nice to have the brakes allow a little slip to slowly lower off of an obstacle. They will probably do that - they will have to in the single motor.

I am also concerned about throttle control when crawling because there is not a low gear ratio. I hope the CT comes with a complete off road setting.

You don't need gears with an electric motor. You can get nearly full motor torque at stand still.

 

[Shumby]

so i deal with VFDs daily and what you are asking for is somthing that is already in practice in Drawworks for the drillign industry. It is simply sofware and can be done. Hell We have Drawworks that can lift well over 1000000lbs and they only have a friction break for and e-stop and "parking" break. Main rason for this is that we do not use the regen cycle it simply gets wasted via a resistor bank.

So what you are asking for is very doable. Now will the CT have it?????

 

[Jhodgesatmb]

If crawl mode is the same, or similar, to low transmission first gear on a truck with a transfer case, the. It is low speed and low torque isn’t it? For sand, snow, and rocks. If it can be done in software the. By all means it should be. With 3 motors nearly anything can be done.

 

[Joe85712]

As about 85% of those who responded to a poll here have no EV experience I am going to assume that you are not familiar with regenerative braking. With it enabled an EV brakes the instant one relaxes pressure on the accelerator or removes his foot from it. With the motors used in these cars it is possible to apply torque to the wheels in either direction be they rotating forward or reverse. You are right that this is managed by the inverter/motor control software and thus what can be done is virtually unlimited. The control wanted for crawl would be much more dramatic than that needed for normal regen but the principles are the same and IMO it is quite doable. That, of course, does not mean Tesla will implement it so send a message to Elon and suggest it.

 

[Joe85712]

I completely agree, off road work with an EV is very different and I think is far superior to non-electric powered vehicles. Having nearly unlimited torque at zero speed gives one quite an advantage in rock climbing. Also having braking by re-gen when not on the throttle with your right foot is also an advantage. When slowly coming off of an obstacle, one might need to have the left foot on the brake pedal to hold the vehicle in position. The other thing is there is no wear on a transmission, transfer case, and center differential. There are no exploding limited slip differentials either. Also you do not have to pay for the fuel being sucked into an engine when it is doing no useful work as is often the case while driving off road.

 

[Jhodgesatmb]

I completely agree, off road work with an EV is very different and I think is far superior to non-electric powered vehicles. Having nearly unlimited torque at zero speed gives one quite an advantage in rock climbing. Also having braking by re-gen when not on the throttle with your right foot is also an advantage. When slowly coming off of an obstacle, one might need to have the left foot on the brake pedal to hold the vehicle in position. The other thing is there is no wear on a transmission, transfer case, and center differential. There are no exploding limited slip differentials either. Also you do not have to pay for the fuel being sucked into an engine when it is doing no useful work as is often the case while driving off road.

I am not sure I agree. I am on my second SUV with regen braking and my wife has an M3 that I have driven some, though not in situations requiring what I would think of as real 4x4 control. I have also owned and driven several true 4x4s (with transfer cases), and have done a lot of driving in deep sand, snow, and rock where low transmission is essential. What I am thinking is that the accelerator pedal in the all-EV is way too sensitive; I would want the accelerator pedal to be detuned so that you could invoke that torque slowly, by having more accelerator pedal play for the same torque. So I agree with what you say about the brake and the regen and the wear, etc., but these aren’t really going to help in the kinds of conditions I have needed low transmission in/for. They seem concerned with driver comfort more than performance. Am I so off base here? I am not sure whether I will ever go off roading with my CT so this is more academic for me.

 

[Saskateam]

This is all a software solution. Tesla could have an off road mode that changes throttle response.

 

[Jhodgesatmb]

This is all a software solution. Tesla could have an off road mode that changes throttle response.

I agree. I was just trying to clarify the performance vs comfort difference. I am certain a Tesla could do lots of things with this platform that would make it the best thing since sliced bread

 

[2Futre4u]

Crawling means real slow. Like under 2 m/hr. The regene would be off by this point and would need a different setup to apply the friction brakes. It would be nice to have the brakes allow a little slip to slowly lower off of an obstacle.
I am also concerned about throttle control when crawling because there is not a low gear ratio. I hope the CT comes with a complete off road setting.

Not true in the Model 3 as of the latest update, regen works all the way to a stop now. Its crazy, we barely ever have to touch the brake pedal now.

 

[Mule Ferguson]

Creep, Roll. Hold All Tesla's

 

[ajdelange]

Not true in the Model 3 as of the latest update, regen works all the way to a stop now. Its crazy, we barely ever have to touch the brake pedal now.

The new X now goes all the way down to 0 mph and I have watched the power meter carefully at the stop to see if it is really regen down to 0 and, unless there is some inertia in the pointer it is. IOW it does not appear that it takes you down to 2 or 3 mph and then transition to friction brakes, The X has "hill hold" mode (don't know whether the 3 or Y have it) and in pops in at 0. I've only had my X a couple of days but I've only used the brake once (when a guy right in front of me slammed on his). Further evidence that it regenerates all the way down to 0 is that the manual says to enable this mode for maximum range.