Turning Quality Metrics

[JVN]

Originally Posted by IKE

I concur with Chris on there must be an "optimal" amount of scrub.

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Originally Posted by Chris Hibner

My point was that there is an optimal amount of scrub (not just less scrub is better).

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Though it makes me nervous to dissent from my much more experienced colleagues...
I disagree on a purely qualitative basis. In 2011 the Robowranglers built a Nonadrive (4 traction + 5 omni) as Raptor's drivetrain. During initial "live fire" tests, we hypothesized that the side-side wheel wasn't actually much of an advantage. We pulled the circuit breaker from the middle wheel, and zip-tied it up -- performance actually increased. (Note: I still believe the side-side motion is useful in some games, just not 2011).

Our plan was to then swap out the omni-wheels for some medium-traction wheels like kit wheels or Colsons to get the performance as described by others in this thread. What happened next was surprising...

We found that in the 4-omni wheel skid-steer configuration (which we've dubbed "butterfly drive) our driver was able to execute some incredibly smooth, and quite precise maneuvers. He was able to also do some "slide" maneuvers we hadn't anticipated.

I would have never speculated that a "zero-scrub" drive would perform like it did, but with Connor on the sticks the thing performed great, and provide benefits that would not have been present in another system.

That said...

Originally Posted by Jared341

The Nonadrive was a mechanical system that had features that could be used to reduce/eliminate turning overshoot (ex. timely deployment of the traction wheels).

Agreed. "Zero" Scrub to "Infinite" Scrub with the push of a button.
Perhaps Connor's ability to "drop traction - lock heading" helped him avoid over-shoot issues.

My thinking is...
Mechanically balancing scrub to prevent overshoot will help with driver smoothness, but are sacrifices being made to achieve this? What do you give up to help your driver deal with overshoot?

Good discussion.

-John