pic: OMNI Drive

[Ether]

Originally Posted by GeeTwo

It is also kinematically the same as mecanum.

Not.

Mec fwd/reverse kinematics is same as standard wheel.

[GeeTwo]

Originally Posted by Ether

Not.

You do have to gear the Killough Mecanum ~40% faster to get the same behavior. I should have said similar (same shape, different scale).

Originally Posted by Ether

Mec fwd/reverse kinematics is same as standard wheel.

I'm not sure what you're saying here. What sort of standard wheel?

[Ether]

omni vs mecanum vs standard wheel chart

[Lil' Lavery]

While each wheel has different kinematics between Omni and mecnanum, as a 4-wheeled system they behave the same. You just swap the "diagonal" behavior in one system for the cardinal directions in the other.

Originally Posted by GeeTwo

You do have to gear the Killough ~40% faster to get the same behavior. I should have said similar (same shape, different scale).

How do you figure.

[jaweth12@gmail]

Check this pdf on page 12
http://www.simbotics.org/files/pdf/drivetraindesign.pdf

[OZ_341]

Team 341 did a variation of this in 2007 and 2008.
However, we placed the wheels at the corners.
Our nickname for this configuration was "Z-drive".

If you do this, you have to be resigned to the fact that everyone can push you around at will.

We were OK playing a "run and gun" game in 2007. It allowed us to always face the goal with the tubes and just drive sideways. Then in 2008 you were not allowed to contact each other, so we did not have to worry about defenders.

We won the Philly Regional with this drive configuration in those two years.
That being said, it has a limited range of uses for most games.

[GeeTwo]

Originally Posted by GeeTwo

You do have to gear the Killough ~40% faster to get the same behavior. I should have said similar (same shape, different scale).

Originally Posted by Lil' Lavery

How do you figure.

Ether answered in the previous post. √2 - 1 =~ 40%.

Originally Posted by Ether

omni vs mecanum vs standard wheel chart

Edit: As I look at Ether's chart, mecanum should be 40% faster, or omni 30% slower.

And thanks for keeping us honest, Ether!

[pmattin5459]

If you haven't built a holonomic drivetrain before, don't design one in the middle of build season. Just use a tank drive. If you're really set on it, then i would suggest mecanums, which can be added to a standard chassis fairly easily, or, if you really want the omnis, put them in the corners diagonally.