Re: Frame design question
 

Poltergeists notwithstanding :rolleyes:

Re: Frame design question
 

I was thinking the same thing, Don. Anyone offering to exorcise a possessed ball? Or is it cheaper just to replace it? #5s are too small to be exercise balls, right?

Re: Frame design question
 

What if frame is seriously convex to the point where it is curves a pocket into itself, like an island atoll and having an opening on the wide side just larger than a ball? Would the bumper have to wrap both the outside and the inside "shore" of the "lagoon"? Could several balls be rolling around inside the lagoon area without being considered possessed, or having penetrated more than 3" into the frame zone? Would all the robot's H/W have to be built up ONLY within vertical space directly above the atoll shaped frame, or could some hardware protrude into the space above the lagoon? Why would there even need to be a bumper inside anyway, since no impact could ever happen there, and only "topologically" it is still the "outside" of the frame?
Kind of tricky getting a shooter concept to fit with this scheme for sure.

-RRLedford

Re: Frame design question
 

You would have to have a bridge across the mouth of the lagoon to attach your bumpers to, to meet <R07-M> and associated Fig 8.3. Note that the balls will still fit under the bumper attached to such a bridge. Therefore if the lagoon is more than 3" deep, you will violate <G46> and <R19>.

I would suggest spending a few more hours digesting the manual before you finalize your designs. You seem to have missed a few key rules.

Re: Frame design question
 

Any convex part of the frame will not be considered as the frame perimeter, if you have a convex are you want the ball to sit in the ball may only go 3" past the line created by wrapping a string about the corners of your robot, that is what defines the frame perimeter

Re: Frame design question
 

From the definitions at the beginning of Section 8...

FRAME PERIMETER – the polygon defined by the outer-most set of exterior vertices on the ROBOT (without the BUMPERS attached) that are within the BUMPER ZONE. To determine the FRAME PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER ZONE - the string describes this polygon.

The string in your scenario bridges the lagoon and crosses the island.

Re: Frame design question
 

Well, my curved "atoll" frame effectively has no vertexes (or ALL vertexes), so it is NOT a polygon. Perhaps, a topologically proper string "wrap" should enter and follow around the shore the lagoon? I guess not.
It appears that the rules clearly are meant to discourage curves in general, and all but the shallowest of concave perimeter shapes in particular.
-RRLedford

Re: Frame design question
 

As you're a rookie, be glad you're in this year's bumper debates instead of last year's. Last year's rules were almost the same, though with an allowed opening percentage, but the way they were written and a required piece of hardware (that had to be included in the opening percentage) practically forced a rectangular design. There was one case where a particularly tricky design to call had to be shown, Q&A by Q&A and rule by rule, where the interpretations of the GDC differed from the design. (Admittedly, this particular limitation had already been accepted by the team. Someone else was pressing the issue.) This year's are much easier, at least for those that were around last year.

And convex curves in general are not prohibited; see http://forums.usfirst.org/showthread.php?t=13723

As for concave perimeter shapes, the only place you can't have them is on the frame perimeter and anywhere you think a ball can get into the lower frame perimeter more than 3".

One thing I might suggest for next year's rules is the changing of the word "string" to either "stretched string" or "rubber band", as a number of people have thought the same thing.

Re: Frame design question
 

Dick,
Where in Chicago are you located? Perhaps we could meet or I can come over and explain some of the nuances of this years game to the team. Just PM me and we can see what we can set up.