Coaxial Swerve Derivation with Paired Modules

[smistthegreat]

http://www.chiefdelphi.com/media/papers/2785 is a tremendously useful paper that outlines pretty much every possible combination of steering and powering modules, including a list of possible maneuvers by combination and notable examples.

The configuration that you're describing is the one labeled {5}. As mentioned earlier in this thread, it is basically a 4 wheeled tank that can translate, meaning that to spin in place you'll have a bit of scrub. One way to avoid this is configuration {13} which powers each side together but links steering modules on the diagonal. This retains the ability to strafe in an arbitrary direction but does a much better job at spinning in place. Check out team 1717 in 2011 for an example of this.

I would tend to agree with other posters in this thread and say that if you're planning on going through with a swerve, assuming the motor rules stay as lax as they are, it wouldn't be a huge step up to just go for 4 independently powered and steered modules.

I would also recommend, if you have the resources to do so (which is a decent amount of money), buying a set of revolution modules from 221 robotic systems and throwing together a chassis to give to your programmers as soon as possible. The biggest hurdle with swerve tends to be software and implementation of controls, as there are tons of resources available mechanically (221 posts cad on their website, team 1640's wiki is incredible, 973 has swerve cad on their website, etc.).