I have already written about LiquidPiston and its XTS-210, but Avadi's idea is even more striking: it is a reciprocating engine that works as a rotary. Imagine an ICE with a single piston.
Avadi's new engine prototype reimagines the rotary, replacing the spinning Dorito with a rotating piston. The 0.25-liter, four-stroke engine has two independent, self-balancing connecting rods ...
the Avadi engine is connected to a central planetary gear, rotating a shaft (like a rotary) that then sends power outward.