A orbitals gear motor with a star-like rotor and a stator with corresponding internal teeth is called an orbital motor. The rotor can roll in a circular motion inside the stator because it has one less tooth than the stator. The fluid flow establishes a pressure variations that drives the rotors' rotation.
Applications for orbital motors contain mobile and industrial settings. They may produce high torques at very slow speeds (approximately 5 rpm) and have very low leaks of oil.