Materials:
The full assembly was constructed from the following:
- Cardstock
- Construction paper
- Cardboard
- Tape (single- and double-sided)
- 2 small, thin nails
Cam Assembly:
The cam was constructed via directions from Karikuri (Cam D). Then, grass was cut out of construction paper and taped to the top rod (Figure 4).
Figure 4: Full cam assembly.
Gear Assembly:
The gear was constructed via directions from Karikuri (Gear A). Two additional gears identical to Gear A were also constructed for the wheels of the bicycle (Figures 5-6).
Figure 5: Gear assembly that connects to the bicycle.
Bicycle and Linkage Assembly:
The bicycle and linkage system were created out of cardstock and construction paper. The frame of the bicycle and body segments of the person were constructed with the only design constraint being that everything should be proportional. The foot is attached to the front wheel using a small, thin nail, and the upper leg segment is pinned to the torso segment with a small, thin nail. The upper and lower leg segments were first constructed to be longer than necessary, and were trimmed until the person could "pedal" the bicycle for a full revolution without the upper leg segment colliding with the handle bar. Finally, the upper and lower leg segments were "pinned" by taping the inside of the lower leg segment to the opposite inner side of the upper leg. This guaranteed that gravity does not push the knee angle into "hyperextension," but rather the knee stays correctly bent through the full revolution of the wheel.
Figure 6: Bicycle and body segment assembly.