limited slip diff..

Kingofjapan · #1 12-06-2002, 11:21 PM

this is an extenstion off of the pan chassis idea.

my idea is to make a lsd. or a limited slip differential so in turning the outside wheel could turn faster for better handeling.

It's almost along the same lines as the digi q's. if you make the back wheels independant of each other and putting two motors via two two broken sets of orange gears.

then here is where i would get confused, wiring the two motors to spin when the forward and reverse. AND wire them to turn independantly when the bit turns. basically attaching two more wires to the L and R contacts on the PCB.

so by letting go of forward, and then pressing either right or left, the outside wheel motor would spin and make it have better grip as well as acceleration.

I am still in the process of thinking this thru. If i do this mod, i will be very very very happy with myself.

post pics when done

1llusI0n · #2 12-07-2002, 12:59 AM

Dude that sounds l33t, i realy hope you come up with this. Keep us updated!!

MTL · #3 12-07-2002, 01:20 AM

ive been wanting to do something like that for sooooo long, but i didnt know how, or what to use...
seems pretty complicated, might have to overhaul the rear/front chassis or something, because it would be really hard to make it realistic, im not too sure...

ive thought about using 2 motors on the rear, so that theres one on each side, and when you turn, there would be less juice to one of them, making the other control the turn pretty much, but then that means one of them has to be moving backwards..maan its too complicated for me..

and then there is the new gearing idea of the digiqs u suggest, which is probably ALOT easier...all you need is like a rear axle on the front, and make new slot holes for it, and connect the motor in the oppoiste direction im thinking...your run time probably wont last that long, but oh wells
ill probably have to try that on the clone

i hope u figure this out, since you are the guy that does those crazy customs

GTR · #4 12-07-2002, 02:13 AM

random question for MTL - who's that pretty girl in ur icon?

MTL · #5 12-07-2002, 02:48 AM

its Hiroko Suto, the Rodeo Drive model/racequeen for JGTC races..
there is another rodeodrive model that i have no idea of her name, but she is also a babe...
the pic is on this page...
http://slab.cool.ne.jp/Photo/suto/suto02/suto02.htm
go to the main for others..this isnt an official site, but just a photographer site

alpha1 · #6 12-07-2002, 03:57 AM

What you are describing is NOT a limited slip diff (LSD). The limited slip diff basically ties both wheels together, which is what's already in the car now, a solid rear axle. LSD's help in acceleration, and not in turning, as the inner wheel is forced to spin at the same speed as the outer wheel, making the turning radius larger. What you are trying to do is modify your bit to work like a tank, independent drives on each rear wheel. There are spots already on the board to do this, but I don't think that the left and right outputs can handle the extra current needed to drive the motor. You may not want to make one wheel turn in reverse while the other is moving forwards, it would be better for you to just stop one of the motors from turning when you want to turn. You will also need to find a way to lock the front wheels from turning from side to side.

Kingofjapan · #7 12-09-2002, 03:13 PM

every single time....every single time...every single time i post an idea for something revolutionary, alpha1 you go and make it seem like it's impossible. i am not trying to induce hostility but you seem to put everyone down.

I of course know what a real LSD is and it is used for turning as well as accelleration. the front wheels wouldn't have to be locked into postion. true, it would work on the same basis as a tank, but i am all about making it work, not the preformance. it seems that you seem to know everything about these cars, yet i don't see you making up any crazy ideas. so leave us alone.

alpha1, please stop the hurting....think of the children.

later

alpha1 · #8 12-10-2002, 12:32 AM

Kingofjapan, I re-read my post and I didn't find anything that I posted that was hostile towards you. I was just pointing out the difference between what you were trying to do and what you were describing. I was only trying to help, which is why you posted this subject in the first place, right? I'm sure you're a smart guy that has a good imagination and you can come up with this stuff. I have no problem with that. In fact, I was one of the first people to reply to your post about the floating rear end. I suggested that you use something that was flexible to keep the rear end in place. How was that hostile?

Yes, I do know a lot about these cars, and I know even more about real cars, in fact my real car HAS AN LSD, but all you want to do make a direct drive setup like a tank.
An LSD does what it's supposed to do, LIMIT SLIP, and provide an equal amount of power to BOTH drive wheels, this helps with traction when under power. If you spin one wheel on a car with an LSD the other wheel will spin in the SAME direction, much like a solid axle. If you spin one wheel on a car with a regular differential, they spin in OPPOSITE directions. This effect allows the outside wheel to move faster than the one on the inside.

And for the second time in this thread, AN LSD DOES NOT HELP IN A TURN. I know what you're trying to do is make your Bit Char-G like a Digi-Q, but if you leave both front wheels free to pivot, your car will spin out.

Nobody's trying to hurt you here...only a child would take my original post as being hurtful.

Kingofjapan · #9 12-10-2002, 12:37 AM

my bait worked. I really didn't mean what i posted, i just need your attention. I needed some help with making a relay switch like someone early discribed, if you could help in anyways, give me a hand, sorry i had to use the oldest trick in the book.

alpha1 · #10 12-10-2002, 12:39 AM

Now you pissed me off! j/k what do you need help with?

Kingofjapan · #11 12-10-2002, 12:43 AM

someone posted an idea for somethat would realy only 25 of the power to one wheel and 50 to another....wtf??

p.s. alpha1: do you have msn??

alpha1 · #12 12-10-2002, 12:48 AM

Maybe a resistor of some sort? Your first obsticle is to get 2 motors into the car, and get the axle seperated. As for wiring the thing up, You may just want to cut the power to the inside wheel instead. In which case, you can just use both toggles on the remote, left one for left motor, and right one for right motor. It would be better for you to use a transistor instead of a relay since we're dealing with low current.

Sorry, but I don't use MSN or IM.

Kingofjapan · #13 12-10-2002, 12:51 AM

the fitting of the motors wouldn't be hard once the lay out of my pan chassis is done. i like the idea of toggle switches. i want to still have the wheels turning out the front, but limit the speed in corners, the resistor might just do the trick. thanks!

kenny_dilger · #14 12-18-2002, 04:01 PM

So how is this mod coming along? This sounds really interesting.

#15 12-18-2002, 04:17 PM

If one rear wheel stopped spinning while you turned it would decrease speed dramatically and you would spin out because its the same as hitting the E-brake in your car, just you can only spin it one way. Also, this would drain your batteries a lot faster and generate more motor heat, and I'm not sure if the motors run 100% as fast in forward and reverse. Also, two motors are unlikely to spin at the same speed, so you will probably end up making permenant left or right hand turns.