Rotor craft noise cancellation system and method
OwnerAlan Richard Greenberginventor
Life of this patent
Estimating the term…
Abstract
Rotor noise cancellation through the use of mechanical means for a personal aerial drone vehicle. Active noise cancellation is achieved by creating an antiphase amplitude wave by modulation of the propeller blades, by utilizing embedded magnets through an electromagnetic coil encircling the propeller blades. A noise level sensor signals the rotor control system to adjust the frequency of the electromagnetic field surrounding the rotor and control the speed of the rotor. An additional method comprises of incorporating a phase lock loop within the control system configured to determine the frequencies corresponding to the rotors and generate corrective audio signals to achieve active noise cancellation.
Claims20
A method for noise reduction in connection with a rotating fan system with propellers wherein said propellers include magnetic portions and wherein said magnetic portions interact with an electromagnet wherein said propellers produce noise and vibrations, the method comprising:
- sensing the noise and vibrations produced by the propellers;
- triggering modulation of the rotation of propeller blades, wherein rotation is optimized in terms of positive and negative compression towards and away from a listener, and
- wherein said propellers rotated by a motor independent of energy generated by said electromagnet,
- wherein said sensing occurs via microphone installments to an inner rim of the propellers encircling a rotor such that as the propeller blades rotate they are noise sensed;
- creating interference using the electromagnet acting upon said rotation of said propellers so that said interference acting upon said rotation of said propellers is controlled so as to enable said propellers to maintain a desired rate of rotation,
- wherein said interference is the result of generating an antiphase amplitude wave, and
- wherein a desired rate of rotation can be achieved by control of rotor angles or varying rotational speed to influence sound pressure and a transported amount of air in each sound wave.
An aerial drone with propeller noise reduction including reducing propeller noise by magnetizing propellers, the aerial drone comprising:
- an electromagnet for creating interference acting upon a rotation of said propellers and applying an orthogonal magnetic field to an electrical field of said propellers to cancel noise;
- a motor for rotating said propellers independent of energy generated by the electromagnet;
- an oscillation sensor for mitigating noise interference from wind and exterior elements by compensating for rotations per minute, air density and speed;
- wherein said rotating propeller system reacts in proportion to said interference acting upon said rotation of said propellers;
- and
- wherein a produced antiresonance is independent of oscillator properties which controls said electric field.
A rotating fan system with propellers disposed upon an aerial drone wherein said propellers include magnetic portions and wherein said magnetic portions interact with an electromagnet wherein said propellers are rotated by a motor independent of energy generated by said electromagnet and wherein said electromagnet creates interference acting upon said rotation of said propellers, wherein said rotating fan system includes a position shift detector of said aerial drone so that said interference acting upon said rotation of said propellers is minimized so as to enable said aerial drone to maintain a steady position above a terrestrial target of interest.
Dependencies are inferred from the claim text.