The Wankel engine—also known as the rotary piston engine—was designed by Felix Wankel in the 1920s and entered mass production with NSU in the 1950s. Unlike piston engines, it is an internal combustion engine that rotates around an eccentric shaft within a triangular rotor, an epitrochoidal cylinder, and performs four simultaneous processes—intake, compression, combustion, and exhaust—in separate chambers. The rotor's three faces form combustion surfaces at a 120° angle; each cycle involves thre