Multistage pericyclic gear reducer

A multistage pericyclic gear reducer, comprising:

• an input shaft rotatable about a longitudinal axis of the input shaft;
• an input external-teeth gear coaxially coupled to and rotatable with the input shaft;
• a first middle planet ring gear;
• a first driver ring gear meshed with the input external-teeth gear and rotatable with the input shaft about a first rotational axis coinciding with the longitudinal axis of the input shaft, the first driver ring gear coupled to the first middle planet ring gear from a first side of the first middle planet ring gear utilizing a first prismatic joint, the first rotational axis parallel with a first central normal axis of the first middle planet ring gear, the first prismatic joint disposed on a plane perpendicular to the first rotational axis, the first driver ring gear configured to transfer the rotational movement of the input shaft to the first middle planet ring gear;
• a first driven wheel, a first side of the first driven wheel coupled to the first middle planet ring gear from a second side of the first middle planet ring gear utilizing a second prismatic joint, the second prismatic joint disposed on a plane perpendicular to the first rotational axis, the second prismatic joint perpendicular to the first prismatic joint, the first driven wheel rotatable about a second rotational axis, the second rotational axis parallel with the first rotational axis;
• a second middle planet ring gear, a first side of the second middle planet ring gear coupled to a second side of the first driven wheel utilizing a third prismatic joint, the third prismatic joint disposed on a plane perpendicular to the first rotational axis;
• a second driven wheel coupled from a first side of the second driven wheel to a second side of the second middle planet ring gear utilizing a fourth prismatic joint, the fourth prismatic joint disposed on a plane perpendicular to the first rotational axis, the fourth prismatic joint perpendicular to the third prismatic joint, the second driven wheel rotatable about a third rotational axis, the third rotational axis parallel with the second rotational axis;
• an output external-teeth gear extended through and meshed with both the first middle planet ring gear and the second middle planet ring gear;
• and
• a central output shaft coupled to the output external-teeth gear, the central output shaft rotatable with the output external-teeth gear about a central axis, the central axis along and parallel with a longitudinal axis of the central output shaft, the output external-teeth gear extended along the central axis.