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Re: Swerve advice
FIRST Team 1075 has been driving swerve for the past 3 seasons with varying amounts of success. During Lunacy we found the Swerve to be very handy with the lack of traction, and used it to great effect. Last year in Breakaway we had the crazy notion to build a Dual Sided swerve drive, which was a complete flop, but we really learned a lot about our drive system and were able to really perfect it for this season.
Here's some thoughts that come to mind:
Tank style only really worked in a wider configuration vs narrow. Found in a narrow config that it wasn't as fast and lots of friction.
This year we have joysticks (we use the Logitech Attack 3) set to the following:
Both Forward = Forward, Both Reverse = Reverse
One full back and full forward is actually what we call Monster Mode (ie Monster Truck, where the back and forward wheels turn at opposite 45s.) This was the biggest change for us. Still great turning without the issues of Tank friction. Doesn't turn on a dime exactly like a tank though.
Switchable Strafe and Lockable Strafe. These are two different buttons as one allows us to quickly switch to a strafing mode a la Mecanum and one locks the wheels full 90 for lining up the poles.
We find that we don't need to strafe that often until we get to the poles and then strafing is fantastic.
Our default driving mode is "Car" for blazing up the field and grabbing tubes.
I totally agree that practice is absolutely key, and I would say it's our biggest downfall. It takes us the full 6 weeks to build so we are lucky if we have any time to practice. It takes us at least one competition to get up to the level we should be. I have seen some horribly driven Swerve drive robots where there is almost too many options and the driver just can't control the machine properly. They will be going full speed down the field and then suddenly turn their front wheels to full 90 and flip right over.... you need to find what your driver wants and uses a lot and then program the wheels to do that specific task.
Driver/Programmer talks are critical with Swerve so that the driver can get the robot to do what they want as logically as possible. (This is what led us to change the turning controls)
Not sure how you are monitoring the wheels turning, but we have a limit switch set up to make sure the wheels don't go past 90 and it allows us to straighten our wheels if communication is lost midmatch.
Biggest improvement by far this year is we went with a gear driven wheel direct from the CIM Motors. Last two years we went with chain and it was awful. Still have chain doing the turning.
I'm not the driver or the programmer so I am just spouting off what I know from being around the team so if you want more specifics/code ideas, whatever let me know and I can hook you up with the right people on the Sprockets
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