Making the Intake Ramp
Tags: polycarbonate, parts, mechanical, and MakerspacePersonhours: 1
Task: Make the intake ramp out of polycarbonate
Last night we went to the Dallas Makerspace to build our ramp for our capture and intake system. Lin had already done the mockup in cardboard and the rest of the team had tested it with the beater bar assembly, but that was too fragile to test on a moving robot. So I took the mockup to the Makerspace to reproduce it in Lexan.
I drew the shape from the cardboard template onto polycarb sheet with a sharpie. My dad had to cut it out using the table saw since I'm not certified to use it at the Makerspace. Then I cold-bent the sides (guides) up using the giant sheet metal bender at the space. It's called a brake but I'm not sure why. It still took a lot of force to bend the sides and I didn't get them all the way to 90 degrees.
Reflections:
Lexan (polycarbonate) is a very tough plastic and we've been using it for FTC for the last two years. My brother and I took an FTC summer camp at the SEEC at UTD where they showed us how to cut this plastic with a band saw and how it could be cold-bent even 90 degrees without snapping. Though that was much thinner material than I used for this ramp. This is the same plastic used as "bullet proof glass." It is very hard to break. We've seen robots that used acrylic (plexiglass) instead and that's very dangerous. It shatters easily with very sharp edges.
Briefly testing the fit of the finished ramp on the robot showed that it had the right size and shape for what we intended. How it actually works while driving around could be another thing all together. We still need to figure out how to mount it to the robot so that it can be folded up into starting position and still strong and stable when in the operating position.
Also, we designed it with as large a mouth as possible so that we don't have to be as precise in driving, can get more than one large ball at a time and can pick up balls at the edges of the robot - like while driving along the side of the competition arena. The downside is that we could risk getting trapped by the 5 ball control penalty in areas of the field that have a lot of balls. We need to figure out a way to quickly move balls out of the way when that happens. If we can't do that, we may have to come up with a narrower ramp.
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