Compound Planetary Gearbox Based Geared Rotary Actuator

A Geared Rotary Actuator(GRA) is a mechanical assembly that is used in aerospace industry for providing controlled motion to secondary flight controlled surfaces. These actuators are used as powered hinges for aircraft structural movements operating against aerodynamic loads for different aircraft manoeuvres. The internal mechanism of a GRA consists of a compound planetary gearbox or an epicyclic gear train. This paper describes the various configurations possible and selection of suitable configuration for epicyclic gear train of a Geared Rotary Actuator.