We all know how a conventional internal combustion engine works, with a piston and a crankshaft. But that’s by no means the only way to make an engine, and one of the slightly more unusual ...

Sandia National Laboratory led by Sandia researcher Peter Van Blarigan that has been testing physical components of free-piston engines which could be 50% efficient. This is about twice as good as ...

While there have been many unusual engine designs over the years, there haven't been many advancements involving the inner workings of the piston engine, except for higher-quality components, since ...

Everyone generally knows about piston and rotary engines, with many a flamewar having been waged over the pros and cons of each design. The “correct” answer is thus to combine both into a single ...

The INNengine e-Rex is described as a one-stroke engine, though it actually has two strokes. But it's not dirty like traditional two-strokes.