My first thought when I saw this engine design was wow, that's novel. Second thought was to model it. Along the way I decided to add an admittedly simple but working transmission and motorize it. 

For those who don't have an electric motor handy I included a manual crank on the righthand side of the transmission which you can rotate to run the engine. It has a pop out, print in place handle which you can extend.

Check out the great video by Driving 4 Answers detailing how the Avadi engine works and it's strengths, weaknesses, and potential application to real world uses.

This took along time to create. I hope you enjoy it. Please message me if you have ideas to improve it or feedback.

I've a few ideas to extend the model. What do you guys think?

1. Create a set of accessories (intake/exhaust manifold). Already started on this…
2. [DONE] Model a set of 3d printable bearings which can be used instead of the store bought bearings. 
3. Source a more powerful motor and see just how fast we can get this thing going.
4. Enclose the cylinder, improve the valve seals, and see if we can create compression.
5. What are your ideas?

Enjoy!