So my team is think about a conveyor belt system to pick up the game balls with. We are wondering what would be the best material to use for the belt. Or if it should be a series of smaller bands.
Polycord. 'Nuff said.
We’ve always used 1’ polycord for our conveyors, as it can be lighter. We have a few tread based designs lying around the shop that we never actually wanted to use.
If you really want to know about the tread then I can go find out, but I recommend using polycord like this… http://www.chiefdelphi.com/media/img/767/767747c54073e3fe1a0db76c373a11c3_l.jpg
Polycord is a good choice!
@JosephC, what did you use as the polycord track? (in other words, what is the black thing called?)
A belt is very, very difficult to get to work well. It has a tendency to “walk” to the side. In professional belting, they do two things to prevent this - First, the framing and rollers are kept perfectly square, and second, the roller is made angled, so the center has a larger diameter than the sides. This way, a correctly made belt will “walk” towards the center, instead of the sides.
On a robot, keeping everything perfectly square is very difficult - virtually impossible, when you consider the hits and movements you get on a robot.
So, to get around that, a lot of teams use the “polycord” stuff. The setup is almost exactly like a normal conveyor belt. You use normal straight rollers, have multiple cords, and have to have some way to keep them straight - groves in the roller might work, or a “comb” stuck between the cords.
So where is the best place to get this polycord stuff at. Also are you able to just buy rollers for them or do you have to make them.
We used poly cards before and were not impressed, maybe we did not use them right. We have been experimenting with belt, so far so good…
What diameter do you recommend for the Poly Cord and what are you using for pulleys?
Im not completely sure what the black roller is in that picture (as its not our robot, its just a picture I found after a quick Google search).
In lunacy I believed we used PVC rollers (not 100% sure, I’ll double check tomorrow) much like the ones used in that picture. 2nd place on Einstein; won IRI(if anyone doubts the power of polycord).
My team has used polycord many times over the years with plenty of success. We first used it in ZoneZeal, but we used 1" wide flat belting material that was melted together. In Aim High, we used 1/4" round solid core, also melted together. It was a bear to melt together all the pieces but it worked wonderfully. After that year we discovered hollow core belting, which is much easier to work with and yields the same result, never had a belt snap.
aaaaaaaaaand this is where I’m probably going to get either a slap or a hand shake from everyone reading, this is a very polarizing design…
In Lunacy, my senior year, we had the brilliant idea to combine the flat belting and the solid core tubing… by melting them together. This design was then fed through the gap in 80-20, and we got a… brush. Behold, our robot from 2009.
…yeah, we did that. And it was awesome.