Initial Physical Prototype:
Here is our first prototype of our mechanism. Although the gears are not grounded in the picture, we were able to create the proposed path from above. Laser-cut gears and links and used M3 nuts and bolts to bring together the prototype. We do plan to do multiple iterations in the coming weeks to test out different link lengths and find a ratio that gives us a larger surface area. A thought we have is to add a rack and allow the gears to move back and forth along it. This would increase the surface area and give us a greater challenge regarding our mechanical components.
Fabrication and Assembly:
We designed this robot to be fabricated mostly from 3D printed PLA filament to avoid machining. After conducting gear analysis we are able to use two identical large gears to drive the system. The servo interfaces one of the 3D printed links via a cutout. The two links of the mechanism have fillets to connect the raised spacer part of the link with the main body. This is to ease the stress concentrations from sharp edges. Finally, we add metric screws with enough length to account for the spacers, as well as bearings when needed. An important consideration is the tolerance of the holes in the 3D printed plastic (~0.05mm). Here is a render of the final CAD assembly.
Electronic Components:
Bill of Materials:
This table includes all materials that have currently been purchased. Materials will be added as we purchase them.
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