paper: FRC #33 The Killer Bees 2013 Software - BuzzXVIII (Buzz18)

[apalrd]

Those graphs definitely show improvement over the years.

I've always liked to feed forward as much as possible for best transient performance. The P-I-FF design feeds forward the steady state output (FF), corrects for steady state errors with I, and handles transients with P (what the D term in a 'normal' position PID would do). FF can be implemented as a math model, curve fit, or lookup/interpolation table.

I agree that mechanical engineers tend to solve problems mechanically, as a controls engineer I disagree with this approach.

[redengin33r]

Originally Posted by magnets

How do your drivers feel about this setup? In the past we've tried some similar things (cheesydrive/right stick steering wheel), but our drivers preferred a tank drive setup, claiming that the cheesy drive was better for driving around an empty field, but when in pushing matches and having to line up, tank drive was better.

As the driver, I loved it. I was as first year driver this year, with pretty minimal experience with Halo and Cheesy drive, so there weren't many habits to break. If you try to drive it like Halo or Cheesy, it will work fairly well, but once you learn how to utilize the quickturn functionality and find the arcing paths that it's great for, you open up some maneuvers that weren't easily accomplished before.

As far as the open field maneuvers- I love it. It allows me to change directions quickly, which often lets me ditch defenders without shifting into low and slowing down. The arcing turns and quickturns were extremely useful when navigating around the pyramid, and I could use either depending on the attack angle. In regard for lining up, I tend to use quickturn (I use it more often than Palardy and Culver designed it for, but it works) paired with a hard stop on the arm to zero against. At the beginning of the season before we installed the hard stops it was pretty squirrely to line up, but that has improved since I've gotten more comfortable with it. With pushing matches, I usually just shift into low and use quickturn to spin out of them.

Overall, it's a pretty flexible drive system. As a newer driver, I loved that it made me less choppy and inconsistent. I'm definitely planning on using it again next year.