Here is a pic of the “harvester” The roller has Pnuematic tubing sticking out of it to prick into the openings of the ball and feed it into a compression chamber with rollers to move the ball.
Looks good but you might want to look at <r08> because we were going to do the same thing and from this thread we have decided not to because it is not really legal. You need to have 6 in of bumper on the bumper peremeter on every exterior corner.
I’m pretty sure they can do it that way, but would need to wrap bumpers around the corners. But, if I’m wrong please someone correct me!!
our front design is drafted with corners like that too, and if it will be illegal i need to know asap. From what I’ve read i think it can be covered within the rules, but I’m not entirely sure…
Very funny, when searching around for accumulator brush material on kickoff, we too discovered pneumatic tubing worked very well for this application. Our accumulator uses nearly the exact same system.
Question: In a design such as this, is the bumper perimeter considered to go inward with the frame? If so, the roller would be outside the perimeter, and thus illegal.
842 knows that their robot Carmen, as originally envisioned, does not meet the bumper rule: http://forums.usfirst.org/showthread.php?t=11170
Further discussion of their frame design can be found here: http://www.chiefdelphi.com/forums/showthread.php?t=71878 Note that this current pic has a portion of that frame removed; it looks like they’re working on a fix to get legal bumpers.
Let’s keep this thread on track discussing only the accumulator roller. It looks like a good design to me. The roller is inside the BUMPER PERIMETER and the soft pieces of tubing shouldn’t harm the balls. My only question, have you done testing to see if that’s enough little hooks to catch balls reliably?
Edit: I see from the video posting here http://www.chiefdelphi.com/forums/showthread.php?p=802925#post802925 it works pretty good. Nice!
Another clever idea from 842, looks good!
I was concerned about pressure feed as well for drawing in the ball. I am anxious to get to school today and try this out. How about attaching the tubes with a short 10-32 stud threaded into the roller? Are those white rings pvc pipe? Are they “grooves” for round tubing?
We prototyped with pneumatic tubing as well. It works very well and “sweeps” the balls in without touching the ground.
Hehe, cool to see one of the ideas we came up with on the first day was used 
We might switch back to this design.
wow this is a very cool and inventive idea…i like it!
have a good season,
Alicia Albrecht
Electrical subteam
The Robettes 2177
I like the design for the ball harvester. I saw the video of it, and it looks like it works really well. I think the little bits of tubing are a great idea!
The bumper perimeter is defined as where a string wrapped around your robot would be. The string will not go into the opening and thus the bumpers would not be on the bumper perimeter. The bumpers in this case would count against the robot in its weight. We are still debating the legality of our bumper and we can make the argument for the configuration we currently have and we are prepared to modify if need be.
Very similar to our design, although we don’t (yet) have the diagonal supports. The notion of 6" bumpers is frightening, to the point of show-stopping (or at least “massive redesign”). 842, what are your thoughts?
Well we feel that we will be allowed with our bumper design. W willadd bumpers to the diagonal sections with 6 inch sections. If we are not allowed we will swap them out with a straight six inch sections. Our argument though will be that the corners will be protected, no bumper section will be less than 6 inches and the weight of the part not on the bumper perimeter will be counted against the robot weight. Even if you had a straight section instead of diagonals the corners would not be protected on the inside. Oh well we will see
Its too bad that the bumpers are such a big issue.
The whole intent is to protect your own robot and other robots on the field, which should be the only things making contact with each other.
Instead, its turning into a wording or lack of wording issue.
I cant see how yours would be deemed illegal based on how you folks plan on putting them on.
Wow I think you are taking a big chance.
If I were your inspector I would rule that your angled bumpers do not qualify as BUMPERS.
I like your design but there is another rule that the bumpers must make first contact with the wall… I think your outside bumper corners should prevent your rollers from hitting the wall first… so that should be ok.
I would be careful though as another robot or trailer can hit the roller area… with the corner of their robot… I can speak from experience in 2006 with a front roller that picked up the poof balls…
It was an issue then… but of course … in 2006 we didn’t have mandated bumpers on the robot… just suggested…so we took many hits from unbumpered robots. We ended up having to use a titanium bar to protect our roller.
Good luck with your design… I hope it works great!!
i think you should look at this http://forums.usfirst.org/showthread.php?t=11170
wow. seems pretty black and white to me.