Strategic Uses of Swerve Drive

[EricH]

Not quite a swerve, but 330 once decided to experiment with mecanum wheels for omni-directional motion. At that point, we'd had a couple years of practice with VEX-scale wheels that we'd had built after seeing mecanums used to move airline cargo containers around, but none full-sized.

Well, we built our set of mecanums and designed the 2005 robot to accomodate a 6WD or a mecanum drive, obtained a couple more kitbot trannies, and set up a mecanum drive on the kitbot and a 6WD on the competition robot. We did some testing, like putting a tetra on a pole and attaching to the kitbot (note: it did a nice circle while going sideways). But what killed that drive was the Defense test: two goals, regulation distance apart, and our 4WD 2003 robot. Objective: get mecanum-bot through the gap past 2003's defense. Result? No success. The 6WD stayed in place, and we did pretty well with it. We haven't had another omni-directional robot, until 2009, where the drivebase rotated under the robot that was held in one orientation by the trailer. (Results: not exactly what was hoped for.)

It's really game-dependant, and team-dependant. A team with swerve experience may choose a swerve when a non-swerve may be better, because they figure they can get it to work--then they face a team that has a non-swerve that beats the wheels off of them. It may also go the other way, but that doesn't happen often.

Chris, the guy who said that "if a team knows how to do a swerve, they shouldn't opt out of it" doesn't quite understand that while a swerve is the best combination of pushing, speed, and maneuverability that is currently available, it is at best a compromise, and many times compromise won't work quite like you think it will. If a team knows how to do a swerve, they know how to do a swerve should they decide that a swerve is necessary.