In planetary gearboxes, the motor shaft is connected to the central pinion called sun gear, located in the center of the gearbox. The sun gear transmits motion to gears called “satellites”; these are fixed to the cage through pins and rotate within a ringed gear located on the internal part of the gearbox frame. The number of planet carriers represents the number of stages in the gearbox. The last planet carrier is connected to the output shaft. Planetary gearboxes are characterized by high efficiency, high precision, low inertia, and compactness. The planetary gearboxes offered by Servotecnica cover a range from 10 mm in diameter in combination with our micromotors up to diameters of 280 mm, which can deliver more than 4000 Nm continuously.