Iteration 1

Our first iteration was a basic Watt’s linkage made out of cardboard cutouts and plastic twist ties. The purpose of this iteration was to play around with ideas we found online.

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Figure 2. Linkage Connection Sketch

Iteration 2

With guidance from the TAs, we decided that bolts would make the assembly of the prototype easier. Now knowing how each of the links will be properly connected, we created a small laser-cut iteration of a Watt’s linkage. One solution we tried to explore was layering the links. To apply this solution to our mechanism, we created two of each link and assembled them incrementally inwards, ultimately sandwiching the output link. 

Figure 3. Basic Laser-Cut Iteration

Iteration 3

We discovered through this iteration that there would be collisions between the links and the grounds, preventing full rotation of the input and output links. This iteration ruled out the layering solution. Moving forward, we decided to try and find a solution through CAD. After many ideas, we found one that worked: creating two ternary links that rotated in parallel. The CAD for this design can be seen below.

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