Tiny wheel

[cadandcookies]

Originally Posted by JohnFogarty

Not being an expert in physics here, but if you go any smaller in wheel size I'm betting the wheels wouldn't support the weight of the robot.

I've never even seen FTC teams use smaller than 4" wheels really.

I think that if you ran a solid aluminum cylinder you could probably support a robot. Heck, I'm willing to bet that it is physically possible to make a robot with 2" wheels. I believe 118 even used <2" omni wheels this year for their actuated system.

I think there are a couple of factors at play. One is definitely packaging-- standard FRC bolt patterns and interfaces don't necessarily fit on a 2" wheel. Then there's making sure you have enough ground clearance (most teams seem to have a clearance >1", more with games that have actual field obstacles), which means you are probably going to have to do a custom frame (good luck using the AM14U for this, or "normal" 1x2 tube). Ultimately there are a lot of interesting design challenges that might go into it (I might designing something with <2" wheels this summer to get a feel for this, actually).

The other is a lack of COTS parts-- the majority of teams don't spend the time or resources to machine their own frames, much less their own wheels. For them, there's little reason to move away from cheap and commonly available kit frame and wheel options.

There's also frankly not been a game that demanded "microwheels," or even really encouraged going outside of COTS components for wheels in recent years.

There's also a tradeoff for effort to design a custom solution versus the (relatively small) amount of weight saved.