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Free spining axel with pololu 90mm wheels


I’m making a 4 wheel rolling robot. I bought a 37D 50:1 motor with CPR encoder for testing. The motors will be attached with the robot with the pololu L shaped bracket, the universal mounting hub, and the pololu 90mm wheels.

The easy solution would be to make the robot 4 wheel drive with an independent motor and driver for each wheel. But in the interest in saving money, I’m think of making the robot 2 wheel drive.

Do you sell a bracket that can be used for attaching 2 free wheeling wheels that would keep the robot level assuming I have 2 drive wheels? Or possibly how to go about attaching the wheels that arn’t powered? All the brackets I’ve seen on the website seem to assume that a motor is attached to the wheel.

The robot might be too heavy to use ball casters for the back.


We do not have a straightforward solution for that kind of setup. You might consider using a slightly heavier-duty ball caster like this one from DFRobot. You might also be able to find smaller casters like that at your local hardware store.