Wildlife warning system for aerial vehicle

1. An aerial vehicle comprising: at least one air flow generator configured to generate an air flow for lifting;

at least one sound producing structure having an opening below the air flow generator and configured to produce sound when the air flow causes air to flow into the opening, wherein the sound producing structures include hollows that generate vortexes producing specific frequencies upon application of an air flow;

further comprising a frequency changing system configured to change a frequency of sound produced by the sound producing structure, wherein changing the frequency includes adjusting a shape of at least one hollow;

further comprising a plugging system capable of plugging at least one of the opening or the flow outlet, wherein the plugging system is configured to plug at least one of the opening or the flow outlet when the aerial vehicle has a flight altitude lower than a predetermined altitude; and

wherein the sound producing structure further comprises a flow outlet out of which air having flowed in from the opening flows.

2. The aerial vehicle according to claim 1 , wherein a plurality of the sound producing structures are disposed at positions corresponding to positions of a plurality of the air flow generators.

3. The aerial vehicle according to claim 2 , wherein at least two of the sound producing structures are configured to produce sounds with different frequencies.

4. The aerial vehicle according to claim 1 , further comprising a detector configured to detect a predetermined target, wherein

the plugging system is controlled to control output of sound from the sound producing structure based on detection of the predetermined target by the detector.

5. The aerial vehicle according to claim 4 , wherein the plugging system is configured to plug at least one of the opening or the flow outlet when a distance between the aerial vehicle and the target detected by the detector is longer than a predetermined distance and to unplug the opening and the flow outlet when the distance is shorter than the predetermined distance.

6. The aerial vehicle according to claim 1 , further comprising a detector configured to detect a predetermined target, wherein

the frequency changing system is controlled for production of sound with a frequency set for the predetermined target based on detection of the predetermined target by the detector.

7. The aerial vehicle according to claim 1 , wherein the air flow generator has a rotor, and the air flow generator generates an air flow when the rotor rotates.

8. The aerial vehicle according to claim 7 , wherein the sound producing structure is located inside a trajectory of rotation of the rotor when viewed in a direction of a rotational axis of the rotor.

9. The aerial vehicle according to claim 1 , further comprising:

a main body;

a plurality of supports extending from the main body and each supporting the air flow generator; and

an extension extending from a distal end of each of the supports in a direction away from the main body in plan view, wherein

at least one of the support or the extension is provided with the sound producing structure.

10. The aerial vehicle according to claim 1 , wherein at least two of the sound producing devices are tuned to generate different frequencies.

11. The aerial vehicle according to claim 10 , wherein each frequency of the different frequencies is tuned to repel a specific type of animal different from the other frequencies.

12. The aerial vehicle according to claim 1 , wherein changing the frequency of sound produced by the sound producing structure does not affect a power produced by the air flow generator.

13. The aerial vehicle according to claim 1 , wherein changing the frequency of sound produced by the sound producing structure comprises increasing a produced frequency by decreasing a length of the hollow, and decreasing a frequency by increasing a length of the hollow.