Next, after studying the wing motion of a ‘typical’ hummingbird, I decided to use a captured ball joint (somewhat similar to a helicopter swash plate), for the pivot and rotate mechanism, and since I try to make my designs 100% 3D-printed, I designed a test fixture to determine the minimal size ball joint I could reliably 3D-print, which ended up being a 6 mm ball and a 6.3 mm hole. With these two dimensions, I was then able to scale the body, wings, and tail outlines I had traced earlier to a size suitable for the wing motion mechanism. With the scale (size) determined, I next designed the gear train for the hummingbird body using the Autodesk Fusion 360 Gear add-in.
Next was the base design. In order to move the hummingbird fore and aft, I needed to change the size of the gears, which also provides the increased torque required for the fore and aft body motion. I designed the base mechanism using a parallelogram to connect the body to the base which facilitates the fore and aft pivot motion, while maintaining body level.
Finally, the flower is my interpretation of the plastic flowers on the hummingbird feeders my wife uses, and the stem was designed to position the flower at the correct point.
You can see more of Greg's creations at hsmag.cc/amlPJF
