[Andrew Schuetze]

This thread is a couple of months dormant but I just began looking at this type of drive recently. Now I am very much intrigued by the cambered, four-corner design posted by Dave. I had been considering a four wheel design with two axles perpendicular. A "plus sign" design. I am worried that this makes the corners of the robot unstable. Adding caster wheels helps but then I conjured up an idea of taking the traditional tank steer set up for a 4 wheel system and just add the second dimension and have a total of 8 wheels on 4 motors and transmissions. I've attached a jpg created from a word drawing so it is rather crude. One motor / transmission would be used per side. It would be prudent to consider using #25 roller chain and sprockets to save weight. The new AndyMark plastic Omniwheels would also be a prudent choice once they become available for weight concerns likewise.

Any and all thoughts welcome.