4. Prototype

Building the first version of the physical model was a lot more complicated than I expected. Turns out cutting a lot of parts out of cardboard is very difficult to do, especially with smaller features. Therefore, I had to make a simplified version of the links in order to be able to cut them out. The main reason why it was difficult was because of the bending that would occur as I would cut around curves, which would deform the link and leave creases that would eventually fatigue from the use of the prototype. After cutting the links out of cardboard, I made holes in every single one of the joint locations. This was also challenging given the precision these holes needed to have with so many links. Any error would eventually add up and sometimes led to some links being slightly too short or long for the full movement to work. There was a lot of trial and error building this prototype. The joints were connected with paper fasteners and wooden sticks.

Figure 14: Prototype of Strandbeesten

The other parts that would not last very long were the gears since they were made out of cardstock and would end up bending when the friction forces from the rotating links were too much for the paper to bear. 

Figure 15: Side view of Prototype

However, the prototype was not gone to waste since it allowed me to learn about the complications of making such a model and get to see the legs work as a result of the rotating motion of the gears.

Figure 16: Front View of the Prototype

The following video shows how the first gear would mesh with the second gear to then produce the walking motion that was desired from the Klann linkage. The bending of cardboard parts and shifting of alignment for some links made the whole assembly difficult to work together. However, this motion still matched the motion from the SolidWorks and MATLAB simulation of the model. It would be a fun project to continue exploring and see come to life with better materials such as 3D printed parts, bearings, and better gluing materials.