[sdcantrell56]

6 wheel drive with either lowered center wheels (~1/8") or omnis on the corners. This has without a doubt been the most successful drivetrain in the past and is very simple to build. As long as you can build a 4 wheel drive you can fairly easily add 2 more wheels. If you really want to improve it, add traction wheels such as ifi and a 2 speed transmission. An even better addition is directly driving the center wheels off the transmission shaft so that even if all of the chains break the robot will still be powered. This requires a little bit more work though and most likely precise machining capabilities.