pic: Frog Force 503 Omnitank Drivetrain (rAC)

[evand4567]

Originally Posted by Electronica1

I was under the impression that all wheels had the be geared the same for this style of drop down, are you considering the possibility of the traction wheels and the omni wheels touching the ground at one? Also what method are you using to keep the chain tensioned?

Other than that, it looks pretty good.

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.