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The size of the assembly was determined from the transportation needs of the mechanism. Since I was planning on moving my prototype back and forth from my home to Texas InventionWorks, I decided to minimize the prototype's dimensions. The prototype's dimensions are 4 inches wide, 8.50 inches long, and a maximum height of 12.35 inches. The sizing of the holes required two iterations. I bought 1/4 inch diameter flange bearings to apply to each joint, however, the bearings did not fit because it is the inside diameter which was 1/4 inches but the outside diameter was actually 5/16 inches. Subsequently, I increase the diameter of the hole by 1/16 inches, and the bearings fit perfectly. The bearings were added to decrease friction during rotation, and they are made out of nylon due to its low coefficient of kinetic friction. The coefficient of kinetic friction of nylon against acrylic is .06, significantly lower than using acrylic against acrylic (.15). A total of 3 bearings were used in the final design, one for each rotating joint. Bolts and nuts were placed with each bearing to hold together the links.
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