Swerve Drivetrain.

[EricH]

Originally Posted by apalrd

Not true.
If they are COTS, and appropriately gauged, they're fine.

Read the entire post. Note that I said "GDC allows" and "again". And know your FRC rules history. Slip rings are an on-again, off-again legal part. (190 had custom ones in 2008 that were legal--there wasn't a prohibition on custom ones then. COTS ones were not legal at that time, IIRC.) COTS ones even more so. This is one of the few times that I remember COTS slip rings being legal for competition use.

And note that the rules change every year.

So, IF the GDC chooses to allow slip rings again, then you don't have to worry about motor wires twisting. Otherwise, you do.

[Mk.32]

That team 1640 doc was exactly what i was looking for, information wise.
Thank you very much.
If we do go this route we are definitely building a test robot off-season first.
And what rule exactly is it that dis-allows slip rings?

[GGCO]

We're using the AM swerve modules, and they're fantastic! The hardest part though is the code base. Make sure you have a TON of time and good programmers to do this.

[Ether]

Originally Posted by GGCO

The hardest part though is the code base. Make sure you have a TON of time and good programmers to do this.

There are a couple of short papers here which explain the kinematics of, and give example code for, 4-wheel-independent steering and speed control.

[EricH]

Originally Posted by Mk.32

And what rule exactly is it that dis-allows slip rings?

This year, there is not one. In fact, they are explicitly allowed.

In past years, rules varied on legality. In future years, the rules may or may not allow them. Hopefully, they will be allowed. But, we can't be certain.

[Mk.32]

k that makes sense.
Thanks for the clear up.

[Mk.32]

Also another question,
with the wild swerve drive modules
http://www.andymark.com/ProductDetai...ctCode=am-0496
do we need to blot both the top and bottom plates down?
or would just blotting the top plate be enough?

[cire]

Originally Posted by Mk.32

Also another question,
with the wild swerve drive modules
http://www.andymark.com/ProductDetai...ctCode=am-0496
do we need to blot both the top and bottom plates down?
or would just blotting the top plate be enough?

You need to bolt both the top and bottom plate, otherwise it will just bend the top bracket.

[Clem1640]

2011 is our 2nd year of doing Pivot Drive. 1640 is very satisfied with the performance of this drive-train. Our drivers love it! We've designed and built our own. Info is available at:
http://wiki.team1640.com/index.php?t...II_Drive_Train

1640 has taken the approach of independently driving and steering each wheel. This puts a lot of investment into the drive-train, but also provides a fly-by-wire flexibility. Drive modes are programmable. The robot has mecanum agility (or better) with tank traction. A hell of a combination.

This is a great drive-train, but not easy to build or program. Many teams which start a Pivot program fail and abandon it. The AndyMark modules are probably a good starting point.