Abstract: The present invention is a rotary internal combustion engine, comprising an outer stator shell which forms several equal-sized stator chambers and an oscillating axle which forms several pistons corresponding to the stator chambers and separating each stator chamber into two sealed combustion chambers. When operating, the combustions of the combustion chambers cause the oscillating axle to oscillate. The oscillating motion is then translated to a mono-directional rotary motion, which provides the power output.