If you're going for maneuverability, you can't ignore the other 2 fundamental concepts that help your maneuverability (i.e. helping you to turn). The Poofs (et al) understand these fundamentals so well that they keep implementing similar designs year after year that are tailored for them. Quite honestly, I don't know if there will ever be a skid-steer configuration superior to WCD since WCD plays so well into these concepts while maintaining a very simple, efficient approach to the design. *Note that the KOP is also setup for both concepts, yet no kit drive train can force you to put your center of mass in the right spot
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Concept 1: Wheel base is wider than it is longer. - This is achieved with the 6WD drop center with since only 4 wheels ever touch the ground in the right configuration for our robot dimensions.
- In a 6WD corner-omnis configuration, this is somewhat achieved by the reduced lateral frictions of omni wheels.
Concept 2: The center of mass should not be close to your center of area.
For a 6WD drop-center there are 2 centers of area depending on which 4 wheels are on the ground -- it's either in the middle of one or the other set of wheels. For a 6WD with omni-corners, it is dead in the middle of the robot. To find the center of area overall, draw lines from wheel to wheel -- where they meet in the middle is the center of area.
- By placing the center of mass in the dead center of the robot with a 6WD drop center, the center of mass is never the same as the center of area. The center of mass is also far away from the sides of the robot, which minimizes tipping issues.
- With 6 wheels on the ground, special care has to be take to move the center of mass away from the center of the robot -- which then may cause tipping issues if moved too far. Moving the mass towards the corner omnis also puts more weight on them, meaning more lateral forces that play into Concept 1.
White Paper which shows the math and the conclusions at the end. Don't let its 'old' date fool you -- it's a gem full of good info.
http://www.chiefdelphi.com/media/papers/1443
You can get by with corner-omni placements and ignoring the 2 concepts. However, you will be much better off by at least understanding the concepts and somewhat adhering to them. Robots that turn easier are not only more agile at mid-high speeds, but also draw less current overall during a match when compared to non-optimal configurations (all else equal).