4WD & steering

[Dilbert Firestorm]

just out of curiosity,

has anyone tried to build or modify a car/truck with 4 wheel drive & 4
wheel steering???

[Bubba]

On Sun, 09 Feb 2003 04:11:30 GMT, Dilbert Firestorm <scanb@att.net>
wrote:

>just out of curiosity,
>
>has anyone tried to build or modify a car/truck with 4 wheel drive & 4
>wheel steering???

Not personally, but I've seen it done. No real reason to. 4 wheel
steering is really only useful when moving fairly slowly and making
very sharp turns. At high speeds it hurts more than it helps.

Bubba
Losi xXx-S- Nekkid right now
HPI Micro RS4- For sale
AE RC10LSS- Also for sale:
http://home.swbell.net/lt1_z28/rc10lss_for_sale.htm

[sanj.varah]

at high speed you want the rear wheels only turning a fraction, say if the
fronts trun 15 degrees, 3 on the back is plenty.

i think the 1:1 monster trucks have it, makes their turning circle better.

sanj

--
Visit my RC Homepage
http://www.schumacher.clara.net


"Bubba" <bubba@beer.com> wrote in message
news:3e45fc79.347556589@news.dallas.sbcglobal.net. ..
> On Sun, 09 Feb 2003 04:11:30 GMT, Dilbert Firestorm <scanb@att.net>
> wrote:
>
> >just out of curiosity,
> >
> >has anyone tried to build or modify a car/truck with 4 wheel drive & 4
> >wheel steering???
>
> Not personally, but I've seen it done. No real reason to. 4 wheel
> steering is really only useful when moving fairly slowly and making
> very sharp turns. At high speeds it hurts more than it helps.
>
> Bubba
> Losi xXx-S- Nekkid right now
> HPI Micro RS4- For sale
> AE RC10LSS- Also for sale:
> http://home.swbell.net/lt1_z28/rc10lss_for_sale.htm

[Bubba]

On Sun, 9 Feb 2003 08:44:04 -0000, "sanj.varah"
<sanj.varah@rolls-royce.com> wrote:

>at high speed you want the rear wheels only turning a fraction, say if the
>fronts trun 15 degrees, 3 on the back is plenty.

With all the trouble it would take to make that happen (no idea how to
do it with off the shelf hardware), it's not even worth the trouble. I
have a theory that high speed handling could be improved with the rear
wheels countersteering slightly, but it's still not worth the extreme
complexity it would cause.

>i think the 1:1 monster trucks have it, makes their turning circle better.

They do, but they also don't see a lot of high speeds.

Bubba
Losi xXx-S- Nekkid right now
HPI Micro RS4- For sale
AE RC10LSS- Also for sale:
http://home.swbell.net/lt1_z28/rc10lss_for_sale.htm

[SimonJ]

"Dilbert Firestorm" <scanb@att.net> wrote in message
news:3E45D4E4.CF495682@att.net...
> just out of curiosity,
>
> has anyone tried to build or modify a car/truck with 4 wheel drive & 4
> wheel steering???
>
A few Maxx's have been donw, it is particularly easy with those, as the
front and rear suspension is identical, all the steering gear is allready in
place on the rear.

[paul werz]

My T Maxx HAD rear steering kit.Its the worse move you can make unless all
you want to do is drive slow in your own circle.It requires a rear servo
bracket for mounting and tie rod ends .If you are interested let me know .I
may want to sell the rear kit

"Dilbert Firestorm" <scanb@att.net> wrote in message
news:3E45D4E4.CF495682@att.net...
> just out of curiosity,
>
> has anyone tried to build or modify a car/truck with 4 wheel drive & 4
> wheel steering???

[Rick Russell]

In article <3e461710.354364249@news.dallas.sbcglobal.net>,
Bubba <bubba@beer.com> wrote:
> have a theory that high speed handling could be improved with the rear
> wheels countersteering slightly, but it's still not worth the extreme
....

I've heard of exotic sportscars that do this. They turn the rear
wheels into the turn slightly during high-speed cornering to keep the
rear wheels planted better.

Probably the most common 4WS vehicle in the RC world is the Tamiya
Clodbuster, which was actually designed for 4WS.

Rick R.

[EJ]

On 1:1 cars the steering works like this:

Low speed turns = wheels turn in the opposite directions
High speed turns = wheels turn in the same direction

I have driven a Honda Prelude that had 4 wheel steering. I could easily take
corners at double the posted speed limit. And yes the speed limit was
decreased due to the turns. The speed limit on the road was normally 50. The
limit was dropped to 30 or 40 in several corners.

I don't know if the extra weight would out way what would be significant
handling changes or not though??? And just like everyone was saying the rear
would only need to turn a fraction of what the front turns.

[cxTurbo]

On 10 Feb 2003 03:07:14 GMT, rickr@is.rice.edu (Rick Russell) wrote:

>In article <3e461710.354364249@news.dallas.sbcglobal.net>,
>Bubba <bubba@beer.com> wrote:
>> have a theory that high speed handling could be improved with the rear
>> wheels countersteering slightly, but it's still not worth the extreme
>...
>
>I've heard of exotic sportscars that do this. They turn the rear
>wheels into the turn slightly during high-speed cornering to keep the
>rear wheels planted better.

Quite a few not so exotic cars used 4WS.
Mitsubishi 3000 GT VR4 and the 80's Honduh Prelude were pretty common
cars.

Even the brand new GMC Sierra Denali has 4WS and it looks like very
impressive system that operates at low and high speeds.

It would be cool to see something like that in an AWD RC car but it
would take a small computer to properly control it. Imagine tweaking
the degree's by just plugging the module into your PC's USB port!

http://www.mazda.co.nz/technology/1021.html
http://trucks.about.com/library/weekly/aa090102a.htm

[Paradox]

"Dilbert Firestorm" <scanb@att.net> wrote in message
news:3E45D4E4.CF495682@att.net...
> just out of curiosity,
>
> has anyone tried to build or modify a car/truck with 4 wheel drive & 4
> wheel steering???

the new XTM monster truck looks ideal for having 4 wheel steering added, the
rear bracket is identical to the front one, and the little spot for the
servo is in the same place.

[paul werz]

follow up to my rear steer kit It comes with mounting bracket ,hardware and
servo with super heavy duty tie rod ends. Manufactured by Rad RC
"Paradox" <l33ta0lhax0r@mindspring.com> wrote in message
news:b27ngq$19r43n$1@ID-109635.news.dfncis.de...
>
> "Dilbert Firestorm" <scanb@att.net> wrote in message
> news:3E45D4E4.CF495682@att.net...
> > just out of curiosity,
> >
> > has anyone tried to build or modify a car/truck with 4 wheel drive & 4
> > wheel steering???
>
> the new XTM monster truck looks ideal for having 4 wheel steering added,
the
> rear bracket is identical to the front one, and the little spot for the
> servo is in the same place.
>
>

[Trowelfaz]

About 16 years ago, there was an electric racing off-road 4WD/4WS car
offered by Mugen It was called the Bulldog. Pretty nice car, but I was never
able to get any speed out of it. You had the option of setting the rear
steering for either opposite or same-direction steering, depending on the
race track conditions (hooked to the same front steering servo). It cornered
VERY nicely, but had a lot of other drawbacks. I never invested the track
time in it and focues on my other racers instead.

Also around the same time, we built a Tamiya Bruiser with 4WS. Since the
Bruiser was built like a 'real' truck, we simply installed a front axle on
the rear and connected a fourth server (1-throttle, 1-front steer,
1-shifting, 1-rear steer). We also installed tires from the Grizzly (much
bigger tires back then). The thing worked just like a real monster truck.
However, it flopped real easy when turning the rear tires in the opposite
direction at high speeds. The real cool thing was turning just the rear
steering, and the very tight turning radius.



"Dilbert Firestorm" <scanb@att.net> wrote in message
news:3E45D4E4.CF495682@att.net...
> just out of curiosity,
>
> has anyone tried to build or modify a car/truck with 4 wheel drive & 4
> wheel steering???