Small Wheels vs. Bigger Wheels

Sooo we’re redesigning our robot, and are wondering if its more beneficial to have bigger or smaller omni-wheels on the chassis. Obviously we would design it to still go over the 10 point bar if we use smaller wheels, but which would be better?

You usually get more power with smaller wheels. With 4" omnis you can get a decent amount of speed.

How many motors do you plan to assign to your drive and what will your general design look like?

Small wheels for torque, large ones for speed. Again, motor quantity plays a large role.

Not how power works. Wheel size is equivalent to a gear ratio. So wheel size doesn’t do much other than allow for more convenient gearing. The only difference the different wheel sizes have other than effective gear ratio is that the 3.25 inch wheels are much better designed than any of the others.

Screw holes
HS shaft or metal inserts
thinner than other wheels
Actually fit with high traction counterparts

The bigger the wheel radius, the less torque force the motor is apply to ground when it rotates the wheel. That’s why with a smaller radius, you have more force. It’s a force times a displacement, in other words work.