TOD controller - knob, wheel, or buttons?

[Knigh7s]

We've got the concept proven...

We're now working out what will be best for everyone? Do you think we need the ability to "fine tune" to an exact percentage, or is: 5%, 25%, 50%, 100% enough?

What do you think?

That is great news! As for the percentages, just curious, would there be any difference between 0 to 5% while driving, I'm sure it wouldnt be to noticable of a differance at all? we are talking about the torque split to the front right? so couldnt you just do 0, 25, 50, 100? well, if 5% isn't really significant of a change, then it shouldnt matter... Bleh, rambling.. sorry...

[taylorRichie]

Can't do the 0%, it's too much stress on the clutch that holds the front from spinning. I believe TOD operates at 5% minimum which is why we would need to have this be our minimum. However 5% coupled with manual hubs turned off should give you nearly the same results as 0%.

Just want to be safe. Also 5% and manual hubs still isn't safe for burnouts, 2 wheel dynos etc.

[Thmstec]

REALLY?!?!?! This is exciting! I would love it!

As for selections, I'm no pro as to guessing what torque splits would be best, but 4-5 selections total would be most desirable for me. My best guesses as to what the best choices would be is: 5%, 20%, 30%, 50%, 70%.

I'm assuming when you listed percentages you meant % going to the front wheels. So obviously 5% for as much power sent to the rear as possible. Now I won't confess to having as intamte a knowledge of the TOD as I'm sure you have now, but wouldn't 100% have the same problems as 0%? And honestly, I prefer power going to the back anyway. As for 20, 30, 70-- I'm just guessing, but I think some testing would reveal the best splits. The only reason I don't include 25% is because of all the cars I've seen/heard of with driver adjustable splits, I've never seen a 25/75 split

[orion]

the rear wheels are not controlled by the TOD at all. the front "shares" torque with the rear. so 100% the the front is just all the torque it can receive, not no rear torque. I like a simple 4 way split, I can't see why I'd need 67.4% the the front

[Knigh7s]

Can't do the 0%, it's too much stress on the clutch that holds the front from spinning. I believe TOD operates at 5% minimum which is why we would need to have this be our minimum. However 5% coupled with manual hubs turned off should give you nearly the same results as 0%.

Just want to be safe. Also 5% and manual hubs still isn't safe for burnouts, 2 wheel dynos etc.

Ah! the light, I now understand. I wasn't really going for a 0%, I was just curious as to why you would have to do something as low as 5% instead of just 0. But I sees the light!

I would prolly stick to you percentage splits, it seems the most logical out of it all. ( 5%, 25%, 50%, 100% )

Keep up the great work!

[VehiGAZ]

I can't see why I'd need 67.4% the the front

That's a really good point. It's nice to have choices, but what would you do with all those intermediate choices? I mean, what driving conditions really demand only a 25%-75% split and nothing else?

The only "forced" split ratio I am interested in is 50%-50% F-R (or 100% engagement of the front axle - however you want to look at it). That would be the equivalent of full-time 4WD-hi, which we don't have. I find the ToD system to be at a loss on smooth dirt or somewhat snowy roads when there is enough traction loss to confuse the ToD system (that constant on-off-on-off-on-off). That's when I find the system lacking and I want a locked 50%-50% split. When the conditions get worse, you go to 4WD low range and slow down. If they improve, regular ToD operation is fine.

I would also suggest to include a 0% front-axle engagement setting or a circuit that cuts power to the ToD entirely in order to achieve RWD (when used with unlocking front hubs). The ToD clutch pack is designed to operate with some slippage constantly, so I am not worried about trashing it with a 0% setting or cutting the power.

[taylorRichie]

I figure the intermediate choices may come in handy, I don't know... With winter driving I'm not sure what split will give the best control between over and understeer. Basically it's not an issue to add it so why not? The only expense would come if people wanted to have infinite control 0-100%. But I didn't think that was necessary.

We can add it, but it will be with a strict warning, I really don't want to be responsible for damage to people's vehicles, and MBEACH really cautioned us against this.

[VehiGAZ]

With winter driving I'm not sure what split will give the best control between over and understeer.

Good point!! I like the balance when in 4WD-low, but who knows what will feel best at higher speeds in 4WD-high.

Normal ToD operation is somewhere around 90%-10% to 85%-15%, so there's not much point in doing a 75%-25% on top of that. Maybe 66%-33% and 50%-50% would be good increments. If I had my druthers, it would be these choices:

ToD Off (100%-0%)
ToD On (85%-15% nominal)
Locked 66%-33%
Locked 50%-50%

[twistedsymphony]

I'd be happy to help in the electronics department if it's needed... I do lots of custom circuits in my spare time (Meche by trade EE by hobie )

as for the splits...

if you're going to split it PERFECTLY 4 ways you're looking at
5% - 20% - 35% - 50% that a clean 15% change with every "click"
however I get the impression most people are really only looking for this:
5% - AUTO - 50% where "auto" is simply letting the TOD do its thing, 5% gives you the best fuel eco and 50% gives you the best traction.

if you wanted it to be really snazzy you could go with "wheel" type adjuster (think like the scroll wheel on your mouse but tighter to hold itself in place) that "clicks" on both ends... meaning wheel it all the way down and click for 5%, wheel it all the way up and click for 50% and then infinite adjustment in the middle... you could have a 2nd switch that would allow you to switch between TOD control and whatever you have the wheel set to.

[taylorRichie]

Thanks for the offer, and insight.

We're thinking 4 positions just as you said, and more than likely it'll be a 5 position dial. This is the where we haven't fully decided.

5-20-35-50-TOD

We have all the firmware and circuitry done, just waiting for another project to wrap before getting the boards shot.

[twistedsymphony]

sounds like you're using an MCU... are you going PIC or AVR... or something else altogether?

[taylorRichie]

Using a PIC microcontroller from Microchip.

And I can't really say "I'm" using anything... My brother is using it

[twistedsymphony]

cool I've done a few PIC projects in my day.

anything you can tell me about the design? which chip model and language are you using, internal or external clock? I'm curious how "picky" the VX is on the timing... I'm assuming not very since people got full lock by just applying 12V.

Are you adding any kind of power cleaning circuitry? automotive 12V systems is crazy harsh since the voltage and amperage spikes and drops all over the place whenever something kicks on or off.

Have you started working on a PCB layout yet, or are you still prototyping the circuit?

Obviously these are more questions for your brother...

excuse me if I'm excited... but it's not often I get to talk about my love of car modifications and circuit hacking at the same time

I understand if you want to keep the design to yourself for resale purposes.

[Ldub]

Thanks for the offer, and insight.

We're thinking 4 positions just as you said, and more than likely it'll be a 5 position dial. This is the where we haven't fully decided.

5-20-35-50-TOD

We have all the firmware and circuitry done, just waiting for another project to wrap before getting the boards shot.

Using a PIC microcontroller from Microchip.

And I can't really say "I'm" using anything... My brother is using it

Youn didn't think we were just going to forget about this...DID YOU???


Oh if only I had a dollar for every promised VX mod I've seen since 04...


Somebody had to stir the coals...

[Thmstec]

Somebody had to stir the coals...

Haha, I was thinking about this thread when I posted in the thread about the brake light. Was going to wait a day or two so I didn't look as desperate! Thanks for beating me to it