Hybrid actuator for helicopter rotor blade control flaps

A helicopter rotor blade comprising:

• a blade body;
• a control flap rotatably secured to said blade body;
• a first primary mover operable to generate a first linear motion, said first primary mover includes an electric machine operable to rotate a motor shaft and a first transmission device which converts a rotary motion of said motor shaft into said first linear motion, said first linear motion operable to generate a high amplitude, low frequency motion of said control flap;
• a second primary mover operable to generate a second linear motion, said second linear motion operable to generate a low amplitude, high frequency motion of said control flap;
• a coupling transmission device for combining said first linear motion with said second linear motion to generate a cumulative linear motion, said second primary mover includes a solid-state, induced strain stack device configured as an annual cylinder so that said motor-shaft extends at least partially through said solid-state, induced strain stack device;
• and
• a second transmission device to pitch said control flap relative to said blade body in response to said cumulative linear motion.

A hybrid actuator comprising:

• an electric machine that generates a rotational motion;
• a first transmission device operable to convert said rotational motion into a first linear motion, said first linear motion operable to generate a high amplitude, low frequency motion;
• a solid-state, induced strain stack device that generates a second linear motion, said second linear motion operable to generate a low amplitude, high frequency motion;
• and
• a coupling transmission device that combines said first linear motion with said second linear motion into a cumulative linear motion;
• and
• a second transmission device to convert said cumulative linear motion to a rotational motion.