Tunable blade assembly, a blade assembly, and a method of controlling vibration
An example blade assembly includes a blade extending along a longitudinal axis between a root end and a tip end spaced from the root end, wherein: the blade is configured to rotate concurrently with a hub and rotation of the blade generates vibrations in the blade, and the blade defines a cavity spaced from the tip end; and a tunable control assembly including a mass adjustable inside of the cavity of the blade to reduce the vibrations in the blade.
1 . A blade assembly coupled to a hub of a flight vehicle, the blade assembly comprising:
a blade extending along a longitudinal axis between a root end and a tip end spaced from the root end, wherein:
the blade is configured to rotate concurrently with the hub and rotation of the blade generates vibrations in the blade, and
the blade defines a cavity spaced from the tip end; and
a tunable control assembly including a mass adjustable inside of the cavity of the blade to reduce the vibrations in the blade, wherein the mass is structured to enable adjustment of a weight of the mass in flight.
2 . The blade assembly of claim 1 , wherein the mass includes liquid in a containment area, the blade assembly including:
a first fluid line in fluid communication with an inlet to the containment area;
a second fluid line in fluid communication with an outlet from the containment area;
a pump in fluid communication with the first fluid line; and
a reservoir in fluid communication with the second fluid line, the pump to adjust the weight of the mass by pumping the liquid from the reservoir, through the first fluid line, and into the containment area via the inlet.
3 . The blade assembly of claim 1 , wherein the mass is adjustable by changing a location of the mass inside the cavity.
4 . The blade assembly of claim 1 , wherein the mass is adjustable by changing a center of gravity of the mass.
5 . The blade assembly of claim 4 , wherein the mass includes a first mass portion and a second mass portion, the blade assembly including one or more actuators coupled to the first mass portion and the second mass portion, the one or more actuators to move the first mass portion independent of the second mass portion to change the center of gravity of the mass.
6 . The blade assembly of claim 1 , including:
one or more sensors to generate measurement data of at least one of a vibratory load, a change of a location of the mass inside the cavity, a rotational speed of the blade, an airspeed, an angle of incidence, an angle of attack, or aerodynamics; and
a controller in communication with the sensors, the controller to activate and deactivate the tunable control assembly to adjust the mass based on the measurement data.
7 . A blade assembly coupled to a hub of a flight vehicle, the blade assembly comprising:
a blade extending along a longitudinal axis between a root end and a tip end spaced from the root end, wherein:
the blade is configured to rotate concurrently with the hub and rotation of the blade generates vibrations in the blade, and
the blade defines a cavity spaced from the tip end; and
a tunable control assembly including a mass adjustable inside of the cavity of the blade to reduce the vibrations in the blade, wherein a weight of the mass is adjustable, wherein the mass includes liquid in a containment area, the blade assembly including:
a first fluid line in fluid communication with an inlet to the containment area;
a second fluid line in fluid communication with an outlet from the containment area;
a pump in fluid communication with the first fluid line; and
a reservoir in fluid communication with the second fluid line, the pump to adjust the weight of the mass by pumping the liquid from the reservoir, through the first fluid line, and into the containment area via the inlet.