Steering a Swerve

[matthewdenny]

So as we continue our development of a swerve module we have just a few (hopefully) sticking points. The biggest is how much torque is normally required to turn a module and hold it in place while driving.

We are thinking about a pg71 http://www.andymark.com/product-p/am-0914.htm gear box with a 1:1 to turn the module itself. Is this in the ball park? What kind of setup do you all use to turn and hold your modules in position?

Is there a calculation that is used...we are a bit stuck.

[jman4747]

So as we continue our development of a swerve module we have just a few (hopefully) sticking points. The biggest is how much torque is normally required to turn a module and hold it in place while driving.

We are thinking about a pg71 http://www.andymark.com/product-p/am-0914.htm gear box with a 1:1 to turn the module itself. Is this in the ball park? What kind of setup do you all use to turn and hold your modules in position?

Is there a calculation that is used...we are a bit stuck.

Search on CD a bit more, I think I remember someone asked this not too long ago here (Post #14): http://www.chiefdelphi.com/forums/showthread.php?threadid=131261 For starters look at what 1640 did. They have a very well documented module. I would think a pg 71 with the RS 775 type is not enough however a AM9015 at 188:1 (PG188) will for sure.

Also look at this: http://www.chiefdelphi.com/media/papers/2426

[asid61]

See thsi thread for calculations:
http://www.chiefdelphi.com/forums/showthread.php?t=129105

[ajlapp]

I've found 100 RPM to be a pretty good target for an FRC swerve steering rate...a PG71 with a 2:1 ratio will get you close and provide plenty of steering torque.

The robot in this (http://www.team221.com/viewproduct.php?id=146) video is running this setup. It's lighter than a fully loaded FRC setup, but we've used the same setup on heavier machines with favorable results.

Medical hoist with PG71 steering for swerve. (http://www.team221.com/viewproduct.php?id=144)