pic: Frog Force 503 Omnitank Drivetrain (rAC)

[Bryce Paputa]

Originally Posted by evand4567

Since it's a form of butterfly, theoretically only the omnis or the tractions should be touching the ground at once, therefore they can use the omnis as a high "gear" and the tractions as a "low" gear. That being said, I'm not exactly sure how the front set of wheels switches from tractions to omnis. Maybe the back traction wheel extends down far enough to pitch the robot up on the front tractions.

Also, the chain tension is a valid point. If you're using an axis to rotate the wheels down that isn't the same axis as the sprockets, you're going to have tension issues, which is why most people use gears between the omnis and tractions and use the interior (or occasionally exterior) wheel axle as the pivot point.

No, when the front traction wheel is up, one of the traction wheels may touch the ground. We're doing this a test to see if the extra torque gained is worth the drag from the omniwheels. With these traction wheels it is not, but with higher traction wheels it might be.

The outer wheel does pivot around the axis of the inner sprocket. It pivots far enough to lift the omni wheels off of the ground.