4 ms·

I was a robotics software engineer on a project that built a mecanum wheeled robot. The big problem is that the rollers are small relative to the wheel. You kno

I was a robotics software engineer on a project that built a mecanum wheeled robot. The big problem is that the rollers are small relative to the wheel. You know how bicycles handle rough terrain better than skateboards? The actual rollers on a mecanum wheel are pretty small compared to the diameter of the wheel they are mounted on. Our robot could handily carry a person on a flat floor (the engineers mounted a chair on a prototype and we got to sit on it and drive it with an Xbox controller - an actually extremely fun activity that could make a nice carnival ride). But if the robot encountered a pencil on the ground, the rollers couldn’t roll properly and things would get messed up. I think I’ve seen suggestions of using the wheels for mars rovers, but a mecanum wheel that works in sand would need the rollers to be very large, so the actual wheel would be huge. That would suck up all your weight budget for your robot. Ackermann steering is lighter. All that said, when you have a controlled environment with a flat floor, mecanum wheels are pretty rad!

lrkrsBlurkn 2y ago
[dead]
freeopinion 2y ago
Omni/poly wheels have similar drawbacks but perhaps less so. Arranged holonomically they provide about the same abilities. Possibly cheaper to purchase and maintain.
regularfry 2y ago
Do they have to be small? Geometrically you'd think that they could be a reasonable fraction of the wheel diameter without clashing. The roller width is the limiting dimension because that defines how close to the wheel axle the edge of the roller can get - would thin, large diameter rollers work?
- TaylorAlexander 2y ago
  Yeah that’s true, instead of small diameter wide rollers, you could have large diameter narrow rollers, like for example bicycle wheels or scooter wheels. Actually you could even use tracks for the rollers, which might be an interesting innovation. That would increase friction and reduce battery life, but there may be some advantages. Of course it would be very complex mechanically! But something made with scooter wheels could be used to navigate around a city for example. That might be interesting.

lrkrsBlurkn 2y ago

[dead]

freeopinion 2y ago

Omni/poly wheels have similar drawbacks but perhaps less so. Arranged holonomically they provide about the same abilities. Possibly cheaper to purchase and maintain.

regularfry 2y ago

Do they have to be small? Geometrically you'd think that they could be a reasonable fraction of the wheel diameter without clashing. The roller width is the limiting dimension because that defines how close to the wheel axle the edge of the roller can get - would thin, large diameter rollers work?

TaylorAlexander 2y ago
Yeah that’s true, instead of small diameter wide rollers, you could have large diameter narrow rollers, like for example bicycle wheels or scooter wheels. Actually you could even use tracks for the rollers, which might be an interesting innovation. That would increase friction and reduce battery life, but there may be some advantages. Of course it would be very complex mechanically! But something made with scooter wheels could be used to navigate around a city for example. That might be interesting.