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We put together our initial prototype, but realized the movement was not as smooth as we wanted it to be.
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In order to fix that, we had to use bearings and would need to 3D print our linkages in order to fit the bearings the way we wanted to. In order to get a snug enough fit for our links, we had to do some tolerancing. On every 3D printer we used, we would test print multiple little pins with diameters 0.1 mm apart to see which size would give us the best fit.
After changing our initial design, we decided to reprint a large slider link and laser cut two gears out of wood, one to fit on the servo and another to be attached to the front of the machine. Because we had to change the placement of the servo, we had to recut the front piece of the box.
Our initial cuts of the slot turned out to be a little too big and the bearing would slip out. Instead of recutting the front part of the wood, we decided to 3D print a railing to be glued onto the bottom of the slot. This allowed for a tighter fit and smoother movement.
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We ended up 3D printing the spring-loaded launcher with no issues, but we later ran into trouble with the rubber band tension of the tabs. With some experimentation we were able to figure out a solution that worked with the cuts we had. We also ended up 3D printing obstacles for the top of our machine.
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