Boxy
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Since the challenge was restricted to a singular game element possession limit, I decided to simplify our robot as much as possible to maximize our speed in cycling. Linear rails would have added enough mass at the end of a pivoting arm to risk tipping the robot during fast rotations, and drawer slides have significant play within each stage. Therefore, I opted for a box tube instead, which is rigid enough to run as a single set with little to no play while staying light enough for fast pivoting.

