An inverted harmonic gear actuator , comprising: a motor stator ; a motor rotor radially disposed within the motor stator ; a wave generator radially disposed within the motor rotor , the wave generator comprising a radially inner surface with a cammed shape comprising a multi-lobed shape ; an actuator output shaft radially disposed within the wave generator ; a flex spline radially interposable between the radially inner surface of the wave generator and the actuator output shaft , the flex spline deformable to conform to the radially inner surface of the wave generator and drive the rotation of the actuator output shaft slower than rotation of the motor rotor , wherein a radially inner surface of the flex spline comprises a first plurality of gear teeth configured to mesh with a second plurality of gear teeth of a gear interface of the actuator output shaft with at least three gear meshing regions ; a plurality of roller bearings radially disposed between the radially inner surface of the wave generator and a radially outer surface of the flex spline ; a first motor bearing axially positioned between the roller bearings and a splined interface of the actuator output shaft , the first motor bearing supporting rotation of the actuator output shaft; a second motor bearing radially disposed between the radially inner surface of the wave generator and a radially outer surface of the actuator output shaft , wherein the second motor bearing is axially offset from the first motor bearing and the roller bearings with respect to an axis of rotation (A) of the actuator output shaft; and a third motor bearing radially disposed between a radially outer surface of the wave generator and a housing of the inverted harmonic gear actuator . a motor stator ; a motor rotor radially disposed within the motor stator ; a wave generator radially disposed within the motor rotor , the wave generator comprising a radially inner surface with a cammed shape comprising a multi-lobed shape ; an actuator output shaft radially disposed within the wave generator ; a flex spline radially interposable between the radially inner surface of the wave generator and the actuator output shaft , the flex spline deformable to conform to the radially inner surface of the wave generator and drive the rotation of the actuator output shaft slower than rotation of the motor rotor , wherein a radially inner surface of the flex spline comprises a first plurality of gear teeth configured to mesh with a second plurality of gear teeth of a gear interface of the actuator output shaft with at least three gear meshing regions ; a plurality of roller bearings radially disposed between the radially inner surface of the wave generator and a radially outer surface of the flex spline ; a first motor bearing axially positioned between the roller bearings and a splined interface of the actuator output shaft , the first motor bearing supporting rotation of the actuator output shaft; a second motor bearing radially disposed between the radially inner surface of the wave generator and a radially outer surface of the actuator output shaft , wherein the second motor bearing is axially offset from the first motor bearing and the roller bearings with respect to an axis of rotation (A) of the actuator output shaft; and a third motor bearing radially disposed between a radially outer surface of the wave generator and a housing of the inverted harmonic gear actuator . <EOS>