AYC-style device for STs

[roee]

I had this idea which has been running through my head lately.

For those who aren't familiar with AYC, it's acronym for Active Yaw Control,
and is a system which is fitted to the Mitsubishi Lancer Evolution cars,
from the 4th generation onwards (the 9th is being debuted now).

The system is basically a computer-control differential, which replaces the
conventional rear differential.
It is able to continually split the power between the two rear wheels,
according to data received from various sensons (throttle, steering,
G-meters, etc).

This way, the behaviour of the car can be altered easily.

Now how does it apply to R/C?

I thought about designing something similar for the RC10GT.
This car, with current drivetrain technology, is simply unable to cope with
the new .12 racing engines, never mind the .18TZ.
It's very simple to work on and design parts for, and is 2wd, which
means drivetrain alterations are very easy to do.

Now, I thought about a unit which replaces the Stealth transmission case
with a custom one, which is similar in design but instead of having the ball
differential, it has clutches.
All the gears are maintained - top shaft, idler, and diff gear.
But instead of having balls in the diff gear, it has two plate-type clutches,
one on each side, which grip it.
The clutch plates will be installed on actuator arms of some sort.
The actuators will, by default, be engaged using springs.
Servo of some sort will be able to pull the actuator back, thus releasing
the clutch from the gear and letting the wheel connected to it slip.

This mechanism, once installed, will have a small controller card with a
microprocessor which will be able to monitor each wheel's speed,
and will also "sniff" the throttle and steering servo control lines (very easy).

This way, the power could be regulated efficiently between wheels.
As a nice benefit, the slipper clutch could be altogether eliminated, it's
just not needed when this mechanism can electornically regulate slip.

Also, REAL (as opposed to the fake one you see on radios) ABS braking
could very easily be incorporated into the system - matter of software
only, the hardware is already there.

Here are some scenarios describing the operation of the mechanism:

1. Straight line acceleration: The system detects straight-ahead steering,
with full throttle, and operates the clutches with identical lock,
effctively creating a solid rear axle for maximum stablity and power transfer
efficiency.
The two clutches will begin at 50% lock, for mimicking the action of the
slipper, and then increase gradually to 100% as speed increases.

2. Turn-in: The system channels all the power to the outer wheel,
creating some slip angle (oversteer) for easy turn-in.

3. Mid-turn: the system decreases the power to the outer rear wheel,
and can either transfer more to the inside wheel or just let the drivetrain slip.

4. Opposite lock: in case you've entered oversteer, the system will help you
correct by transferring all the power to the inside wheel.

As you can see, it seems like a pretty fun - even if crazy - thing.
I can do all the electronics and software for it,
but I have no experience with fabricating the mechanics.

If someone wants to chime in and help make it work, this would be fun.
If not, I'll just send it to the big "recycle bin" in my head and stop wasting
time at work ;)

Anyway, I hope you think it's a good idea as I do :D
I figure a RC10GT with an OS .18TZ equipped with such a system could
give a nice fight to buggies at the track!

[roee]

Probably too boring (or insane :D) for most :)

I'll just go drive my R/C around and shutup.

[Jetskiboy77]

It sounds more complicated then you make it seem. But if you could do it, that would be insane.

[QUAKE&SHAKE]

How different is what you speak of to the Torsen Diffs like 1/8 buggies use. You know of them?
They limit wheel spin on the tire with the least grip sends power to the tire with most grip, Mechanically not electronically though.
Like what you mention in #3 example above.

I use one but on 1/8 scale not 1/10ST

[-=ADA$=-]

its similar to torsen diffs, but one thing, as i know IFMAR bannes active traction control instruments, so torsen is race legal, and system like this wouldnt be, but its interesting idea for sure

[roee]

Torsens are better than nothing, of course ;) But:

1. They offer no on-the-fly adjustablity, which might be OK for a buggy
with 4wd but less than ideal for a truck with close amount of HP on 2wd;
2. *I think* they can not lock when one wheel is entirely in the air;
3. They are heavy and complex.

Torsens are usually used in the center differential of real cars, and not
on the axles, IMO.

The real deal here is the electronic control, which allows for plenty of
useful features, such as ABS, slipper elimination, effective traction control,
increased yaw to overcome understeer tendencies which most trucks have
(they come this way from the factory, to try and compensate for the
rear wheel drive).

It's really not that complicated, I hope :)
Someone which is adept with CAD software and has access to a CNC
machine is all that seperates me and a prototype :D

[Esteban]

And I thought Acura was on to something totally new with their SH-AWD system on it's new RL.
I think I understand what you're talking about. The differential would be servo activated/ controlled, like the shifting mechanism on the Revo, right?
Cool

[roee]

I think I understand what you're talking about. The differential would be servo activated/ controlled, like the shifting mechanism on the Revo, right?
Cool

Almost. It will be controlled, but not necessarily by an EXTERNAL servo - it might be a small internal electric motor of some sort.
The control won't be directly through the remote but by an onboard
computer.