Another Drivetrain Idea - "True Octanum"

[jman4747]

Originally Posted by Certified Nerd

Why not just use 8 sets of 2 omni wheels? Wouldn't this work fine and be much cheaper?

Do you mean 2 sets of 4 = 8?

8 wheels*2=16

16*$18 a wheel (4" VEX Pro omni) = $288

2 sets of 4" VEX Pro Mecanum = 8*$30 = $240

8 total 4" VEX Pro omni wheels = $144

[JohnGilb]

I don't think this really helps you.

So, here's the thing (Ether or one of the mecanum experts can correct me here): in an ideal environment, there is no difference in power applied forward/backward vs strafe left/right. The reason you see bias in the real world is because of the internal friction in the roller bearings - this effectively means the wheels aren't providing power at 45 degrees, but rather some other number that is typically biased towards front/back.

All you're doing here is combining two imperfect drives orthogonally, so instead of max speed in one direction and 60% in another, you're probably going to have 80% in both, as the fast drive will be "dragging" the slow drive.