4-Wheel steering

Ogre

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It will be interesting seeing what impact this plus thrust vectoring has on turn radius.

We have crude thrust vectoring on our tractor using differential braking. You can completely stop one tire but not the other. At that point the tractor can pivot on that stopped tire. Wouldn’t work super well on pavement, but combined with 4 wheel steering you could probably do some crazy tight corners.

I guess that’s bit different than thrust vectoring because you actually have to apply braking force for it to work.
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rr6013

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It will be interesting seeing what impact this plus thrust vectoring has on turn radius.

We have crude thrust vectoring on our tractor using differential braking. You can completely stop one tire but not the other. At that point the tractor can pivot on that stopped tire. Wouldn’t work super well on pavement, but combined with 4 wheel steering you could probably do some crazy tight corners.

I guess that’s bit different than thrust vectoring because you actually have to apply braking force for it to work.
RWS would work for thrust vectoring nicely. It need only initially change the inertial vector to intiate a turn; thrust vector drive-by-wire controls the resultant radius forces to complete the turn; using yaw sensors to regulate around an imaginary pivot point(s).

I call “dibs” for first look at the code to drift CT’s.
 

ldjessee

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Thrust vectoring, traction control (ie, applying the brakes), and RWS could make turning radius very tight... but might be less than nice to your tires, depending on several factors. Hope there is a setting or it is part of the modes... like in chill, the combination is the least damaging to tires, while in track mode, it is the most damaging (but tightest turning at speed)...
 

AENewman

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4WS would allow the TCT to make hairpin turns, and even allow “crabbing“ like a tiller on a ladder fire truck.

This feature would be especially useful off road, such as with negotiating tight switchbacks on mountain roads, as well as maneuvering through older (read: European) streets.

Would the juice be worth the squeeze?
We had 4 wheel steering on a Prelude years ago; was great for cornering and parking, could not do crab walk. Wheel/tire clearance was not a problem. 500k miles and no problems.
 

alan auerbach

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4WS would allow the TCT to make hairpin turns, and even allow “crabbing“ like a tiller on a ladder fire truck.

This feature would be especially useful off road, such as with negotiating tight switchbacks on mountain roads, as well as maneuvering through older (read: European) streets.

Would the juice be worth the squeeze?
Depends on what juice you're after. "Crab"? Sure. Want to do a sharp turn by braking one rear (sometimes called a "cutting," "braking" or "tractor" turn)? No -- unless the fronts were steer-turned to a more acute angle than would be safe for a road vehicle.
 


Ogre

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Depends on what juice you're after. "Crab"? Sure. Want to do a sharp turn by braking one rear (sometimes called a "cutting," "braking" or "tractor" turn)? No -- unless the fronts were steer-turned to a more acute angle than would be safe for a road vehicle.
Tractor turns would be more useful than either tank turns or crab mode… but you are right, the steering isn’t tight enough to have it make sense.

If the spy video a while back is accurate, it looks like the turning radius with 4 wheel steering is going to be A+ which is what most people are going to care most about.
 

firsttruck

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Tractor turns would be more useful than either tank turns or crab mode… but you are right, the steering isn’t tight enough to have it make sense.

If the spy video a while back is accurate, it looks like the turning radius with 4 wheel steering is going to be A+ which is what most people are going to care most about.
Hopefully the Cybertruck with 4WS will be the most maneuverable full size crew cab truck ever.

Could it take the Moose Test trophy from the long reigning champ 1999 Citroën Xantia Activa V6 family sedan ?

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Moose Test
https://en.wikipedia.org/wiki/Moose_test

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Moose test - list of the fastest and slowest cars

Results in Teknikens Värld's moose test | The World of Technology
Teknikens Värld (Swedish tech & car web magazine)
By Mattias Rabe [email protected]
https://teknikensvarld.se/algtest/

How does your car handle a powerful evasive maneuver? Take a look at Teknikens Värld's list of the speeds at which hundreds of different cars pass the moose test. Most cars pass the so-called moose test without any major problems. But sometimes it gets worse and sometimes it has gone really bad, for example when the Mercedes A-Class overturned in 1997. How bad it can go, you can see in this film. What in the cone path results in some overturned cones corresponds in reality to uncontrolled skidding in oncoming traffic. Good cars can handle just over 70 km / h, they really well just over 80 km / h. The track is set up according to a prepared pattern and the test is run on dry asphalt, with some exceptions (marked in the table), and with as many passengers the car takes, weights in the luggage up to maximum load and tire pressure according to the car's specifications.

In the video below, you can see the difference between a car with ESP and one without an evasive maneuver.



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Go to the web site (in Swedish) to see the table of vehicles tested
The table was last updated on January 21, 2021.

Tip: You can sort the list by car model, model year, damp track and speed. At the end of the list you can comment. Cars marked with * are cars that are very close to tipping over.

https://teknikensvarld.se/algtest/


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Why New Cars Keep FAILING the Moose Test
Driven Media
Sep 17, 2021

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Ogre

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Hopefully the Cybertruck with 4WS will be the most maneuverable full size truck.

Could it take the Moose Test trophy from the long reigning champ 1999 Citroën Xantia Activa V6 family sedan ?

Moose Test
https://en.wikipedia.org/wiki/Moose_test


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Why New Cars Keep FAILING the Moose Test
Driven Media
Sep 17, 2021

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Model Y and Model 3 have done quite well on the Moose test.

Cybertruck is big and heavy. Even with 4WS that’s a bad combo. Big heavy things don’t change directions quickly.

I think it’ll do decent, but not take any kind of price other than perhaps ”Best truck”.
 

ldjessee

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Model Y and Model 3 have done quite well on the Moose test.

Cybertruck is big and heavy. Even with 4WS that’s a bad combo. Big heavy things don’t change directions quickly.

I think it’ll do decent, but not take any kind of price other than perhaps ”Best truck”.
Depends what the suspension ride height is set to when they perform the test. I am going to guess the lower it is, the better it will do.
 

firsttruck

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Model Y and Model 3 have done quite well on the Moose test.

Cybertruck is big and heavy. Even with 4WS that’s a bad combo. Big heavy things don’t change directions quickly.

I think it’ll do decent, but not take any kind of price other than perhaps ”Best truck”.

Winning Best Truck would be great
 


firsttruck

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The moose test may be more important for Cybertruck than for ICE trucks & F-150 Lightning EV.

Most full-size pickup trucks are sold in U.S. and Canada. While both countries have moose the much more common danger is deer.

Deer are normally shorter than moose and with the huge tall front hoods on most ICE trucks & F-150 Lightning EV the probability that the struck deer will go over the hood and through the windshield is lower.

The aerodynamic frunk of Cybertruck is much lower so a struck deer has higher probability of going on to the frunk and impacting the windshield.

So the Cybertruck being able to do stable evasive maneuvers or if impact is not avoided the strength of the windshield is more important than for ICE trucks & F-150 Lightning EV.
 

Ogre

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I don’t worry over much about deer going through the windshield, Teslas are designed for that kind of impact. The Tesla has a natural cow-catcher shape. The deer will be deflected over the roof as opposed to a flat nosed truck where the front end will have to absorb the entire impact.

Far more concerned with the impact of hood size on visibility and pedestrian safety then I am on what happens if my shatter resistant thick front windshield has to deflect a deer.
 

Crissa

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Deer have made it through Tesla windshields, but only when they do their super-leap trying to clear the car.

Not much you can do about that unless you want the cab six feet in the air.

-Crissa
 

firsttruck

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Deer have made it through Tesla windshields, but only when they do their super-leap trying to clear the car.

Not much you can do about that unless you want the cab six feet in the air.

-Crissa
"cab six feet in the air". Oh, you mean like the competition. Yeah, right. Oops, I mean wrong. Bad competition.
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