In designing our robot arm, our first priority (for both squads) was to avoid corners, which we learned in class collect stress. Our reasoning was that eliminating stress hotspots would more evenly distribute the force over the body of the arm, and thus prevent locations of especially high deflection. Our second priority was to eliminate excess volume. For both squads, this dual mandate led us to cut out large circles from the body. RΩ also cut out little circles where there existed very little stress. Rα fileted the edges of the arm, and rounded out the preexisting cuts.
We employed both of these additional methods of removing volume as we combined our designs. Starting with Rα’s arm, we added many of the small circles from RΩ. We figured that the decrease in volume would outweigh the increase in deflection. However, testing revealed that the smaller circles cut into the Rα design actually increased the score.
As we returned to the drawing board, we kept with Rα’s design as the template. This time, we removed circles and ovals only from regions with very little to no stress. We tested the arm with each additional cut, and removed the cut if it did not lower the score. This gradual process of optimization led us to our existing design, as seen below.