Cyrus Tabrizi, 12/26/12
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      Right next to the winch's motor, there is a large XL motor whose unwieldy torque caused issues until a suitable mount was made for it to run the robot's lifting tray. The tray itself works so smoothly it's practically origami. It has two sections that fold together to create a bowl in which it can collect trash. When it is folded, it folds over the XL motor and does so at a right angle. When it unfolds, it can lower to just above the water in a bowl shape or it can continue, unfolding completely and dumping its contents into the water. The folding action is one that is hard to motorize –it requires a combination of torque and distance that will give the liftarms the leverage they need to fold back in and the degree of motion that allows it to extend completely. To do this, the XL motor was geared down with a worm gear and a 40t gear –a difficult combination to implement sturdily and in a confined space. Ultimately, it runs, but only with the help of a couple of strategically placed rubber bands. The tray itself works beautifully and holds large objects in place long enough to dump them at shore –small objects, don't work so well.