Thread: pic: 1825
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Unread 21-02-2007, 16:41
WesleyC WesleyC is offline
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Join Date: Jan 2007
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Re: pic: 1825

For one, small quantities of this material are rather difficult to produce. For another, the larger the quantity of material, the more stable it is. We decided fairly early on an I-shaped beam for this design of an arm, and the fiberglass/foamboard material fit the bill perfectly. The thickness of the arm's pieces is in this case dictated by the width of the foamboard "core" of the material, the width of the pieces were chosen by the material necessary to withstand certain forces and the necessity of embedding plywood in certain points to prevent screws pulling through the material, and finally the width of the arm assembly was chosen as being excellent for:

1. Mounting our wrist and claw inside, leaving joints less exposed to being hit
2. Running a cable/chain link between a motor on the back frame and the wrist
3. Running all wires, cables, and the claw control rope down the center of the I structure

All that said, it also looks cool.