pic: ABS-122, shifter-in-tube chassis

[GeeTwo]

Originally Posted by GeeTwo

On the other hand, if 60% of my robot's weight were on the front wheels in a static configuration (and presuming I had at least six wheels), I would be VERY worried about the robot falling on its face in a braking maneuver.

Originally Posted by MichaelBick

That is completely dependent on CG height and, given 4587's short robot, probably not a major risk.

I know it sounds strange, but if this is the case, I would seriously consider not driving the back wheels at all -- save the chain and sprockets and heartache. I might even consider skipping the back wheels and putting some pegs or furniture gliders. Here's why: If 60% of the weight is on the front wheels, the CoG is closer to the front wheels than the middle wheels. If the CoG is low enough that you are "not at major risk" of braking hard enough to tip forward, you are probably "at minimal risk" of ever needing to put weight on the rear wheels, and at "fuggetaboudit" for need to drive those rear wheels.