Is there a reason you dont see 3 wheel drive bots?

rwgast_logicdesign

So in yet another idea to get more power in sand and rid my bot of a caster I started thinking why not use a matching third wheel set up on a stepper/servo for rubber motion which can turn in sync with the differential drive and then put a gear motor and hbridge on that wheel also..

Searching for 3wd robots only turned up omni designs

rjo__

If you did it that way, you would only need one motor.... and you could put a big cylindrical tire on it for traction. A potential use for peanut butter jars!!! You could even put the motor inside the tire:)

rwgast_logicdesign

Well i know youd only need one but the point is to get the torque and traction of 3 motors. Although sticking the motor in the wheel is a cool idea, probably not so easy when you consider the wires though

GordonMcComb

Roger Arrick has long sold a kit with this design, or a variation of it. It's no better or worse than anything else.

If you're wanting to go in sand you could use a 4WD. Each side can run off the same motor, or you can use four motors, if they're small and cheap enough. Here's the general idea usign small servos:

http://www.budgetrobotics.com/item/4WD-Base-Chassis-233

Both 4WD and 6WD chassis are the preferred method for travelling over loose earth. They even beat out tracked, because the sand gets into the mechanism much more readily.

-- Gordon

Duane Degn

GordonMcComb wrote: »

6WD chassis are the preferred method for travelling over loose earth.

Apparently NASA thinks they work for traveling over loose mars as well.

erco

Duane Degn wrote: »

Apparently NASA thinks they work for traveling over loose mars as well.

Less bad joking and more hall-hacking, Duane!