A balancing act

I’m repackaging my robot and have a balance issue. The base is a Pololu base with a Tamiya 70097 dual-motor gearbox and a caster on one side.

Since the motors are heavier than the caster, and sticking out near the opposite edge of the platform, the whole robot falls onto the motors instead of the caster.

I tried pushing the batteries to the other side to get it balanced, but the best solution is to get some sort of caster under the motors.

Any suggestions of a good way to do this?



The problem with putting a caster under the motors is that the clearance is very low, and we do not know of a small enough caster. That leaves three options (that I can think of): you can put a ball caster to the side of the gearbox, put a slippery caster substitute under the gearbox, or balance the robot. For the “slippery substitute”, you might glue a nylon cap nut under the motors.

It would be best to achieve the balance solution so that most of the weight is supported by the tires rather than any caster(s). That way, the caster will roll better, giving your motors better control and making it less likely that the caster will cause your robot to get stuck. Of course, you can still work to limit the weight on the caster even if you go for the cap nut or other caster.

- Candice