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However, for the final build, we changed the dimensions of the oar to make it look more proportional to the bigger size of the boat base. The new dimensions could have allowed for a more comfortable and sturdy design of the ball and socket joint to couple the oar with the rest of the linkage system. In the future, we might consider ordering a premade ball-socket joint to ensure reliability.
In general, we are happy with the shown result though, since we improvised the half joint rather successfully using a heat shrink that joined both pieces and allowed for the desired range of motion.
- Size of linkage system(bigger; for bigger trajectory)
The novel nature of the linkage system demanded that during the process there would be some amount of experimentation. Having never designed a six-bar linkage system from scratch, our philosophy in choosing the size of the links and axles was that, if we missed the mark for optimal dimensions, our prototype would be easily fixed by reprinting a problematic (non-fitting) link. Therefore, it was decided that we would use a relatively compact size and density during prints. This meant scaling down the dimensions of the designed trajectory but also a more flexible manufacturing process where reprinting a piece would not take very long and was easily interchanged. Thus, we also decided for on a more modular approach to the assembly. Any piece was rather simply replaced or interchanged by disconnecting the axles and surrounding pieces and removing itthem.
The result was a non-strictly-planar motion. This means , the mechanism was not sliding perfectly in one plane but also in a second one slightly. While it could certainly be described described as some sort of “play”, we decided that restraining the linkage system to be sturdier would put too much stress in on the pivot section of the oar component, possibly snapping into place. ThenHence, some out-of-plane motion was to be tolerated.
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Overall, one thing we learned when designing, manufacturing, and assembling the robot was that, in inventing and coming up with a novel build, the iterative approach is especially satisfactory.
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Decisions and compromises had to be made, and through these, we exercised and therefore improved some executive and decision-making skills. In developing the robot, we went through different iterations and had to adapt components to create the best possible version we could.
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