Differential steering

[Danjr1]

Has anyone ever tried using a differential with individually-activated brakes on each output shaft to achieve steering?

[robotwars]

I did it on one of the old pay to drive robots years ago!!!

Worked ok actually !

[Danjr1]

I'm just speccing up a heavyweight. the issue would be finding a diff suitable!

[maddox10]

Firestorm did it, and did it well. But it wasn't a cheap, easy or light drive-system.

But they used smaller motors in stead of brakes to control the turning ratio.

Suitable diff. The Old Litton/diff setup Roger Plant sold was fine in that respect. You can find simular sets in disabled 3wheel scooters.

Or else look here

[Danjr1]

im thinking dirt cheap! its just pie-in-the-sky thinking at the moment but im thinking a diff with mini moto disc brakes on the output shafts, activitated by 3-4 high powered servos on each side. 1 motor powering the diff with twice the amount of power of the bosch 750. ideally, id want a open diff (same kind of appearance as a lego technic diff)

[mattsdragons]

ive got an old diff so if you want it, you can have it. i doubt ill ever use it

[maddox10]

im thinking dirt cheap!

Who doesn't? Oh, I see.

its just pie-in-the-sky thinking at the moment but im thinking a diff with mini moto disc brakes on the output shafts, activitated by 3-4 high powered servos on each side.

so, 8 servo's working in 2 groups. Main question, what does a high power servo cost?

1 motor powering the diff with twice the amount of power of the bosch 750.

Mag C40, Perm 080 (if you find them) Black Max, Cheap???
If you want cheap, powerfull and dirty, car starter.

ideally, id want a open diff (same kind of appearance as a lego technic diff)

Get out the dremel then.

[PJ-27]

I was thinking car starter motor too, would be perfect.

[Ellis]

They're single direction aren't they?

[PJ-27]

Apparently it's not easy to, but exactly why I don't know. I thought they just had advanced magnets so spun faster one way than the other, like drill motors. They are series type motors though so will keep spinning faster and faster until the destroy themselves and draw a serious amount of current!

But, very powerful, loads of torque and dirt cheap.