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We 3D printed several key components in the design, such as the track for the follower to roll along or small mounting components, as their geometry was difficult to create out of flat sheets of material. For hardware, we used a variety of M4 and M5 bolts and nuts to secure each component. We designed certain fasteners in compact locations so we used smaller sized bolts there, and we used long bolts to secure multiple components together such as the lazy susan and gear assemblies. To simplify our design and manufacturing process, we utilized prebuilt shaft mounts and linear bearing mount blocks; the solidworks models we used are shown below. Using these meant we did not have to design and manufacture our own versions of these and could just design to the existing, robust part.
We began manufacturing by cutting out the main drive gears and food turntable. We printed the track profiles that the follower would run on and bolted them to the turntable. We assembled these initial gears on a small, temporary main platform to validate that the gears would mesh well with low friction, and they did, so no redesign was necessary for the gear dimensions. The gears are highlighted in green and the track is highlighted in blue.
After the turntable, we assembled the initial assembly designed to constrain the topping container and oscillate it on the upper rail system as the crank slider mechanism moved. This rail system, shown in the video below, did not work as intended. Ideally, the follower would have been able to create an upward force on the rail system and raise the food dispenser as it slid on the crank slider shafts. We assembled the parts and tested the rails and saw that the follower created a large rotational moment on the linear bearings which caused them to seize whenever the follower shafts pushed up into the rail system.
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