Unmanned aircraft and information processing method

1. An unmanned aircraft comprising:

rotor blades;

a duct that shrouds the rotor blades and through which airflow generated by rotation of the rotor blades passes; and

a processor that controls rotation of the rotor blades,

wherein a ratio of a height to a width of an inner space of the duct in which the rotor blades are shrouded is at least 0.5.

2. The unmanned aircraft according to claim 1 ,

wherein the width of the inner space is at least 140 mm and at most 280 mm.

3. The unmanned aircraft according to claim 1 , further comprising:

a microphone or a loudspeaker,

wherein a sound pickup direction of the microphone or a sound output direction of the loudspeaker is set to a direction toward a quiet area, the quiet area being relative to a first noise generated by rotation of the rotor blades and dependent on the ratio.

4. The unmanned aircraft according to claim 1 , further comprising:

a mechanism that adjusts the ratio of the duct.

5. The unmanned aircraft according to claim 4 ,

wherein the mechanism includes a mechanism that adjusts the height of the inner space of the duct.

6. The unmanned aircraft according to claim 1 , further comprising:

a sound processing device,

wherein the processor executes sound processing related to the sound processing device based on a quiet area, the quiet area being relative to a first noise generated by rotation of the rotor blades and dependent on the ratio.

7. The unmanned aircraft according to claim 6 ,

wherein the processor:

obtains a position of a sound processing target of the sound processing device; and

controls at least one of a position and an attitude of the unmanned aircraft to include the sound processing target in the quiet area.

8. The unmanned aircraft according to claim 7 ,

wherein the sound processing device is a microphone,

the sound processing target is a sound source to be recorded by the microphone, and

the processor controls at least one of a position and an attitude of the microphone to include the sound source in a sound pickup area of the microphone and to cause the sound pickup area to overlap the quiet area.

9. The unmanned aircraft according to claim 6 ,

wherein the sound processing device is a microphone,

a sound processing target of the sound processing device is a sound source to be recorded by the microphone, and

the processor:

obtains target sound characteristic information including a characteristic of a sound generated by the sound source or sound correlation information correlated with a characteristic of the sound; and

identifies the quiet area according to the ratio and the target sound characteristic information.

10. The unmanned aircraft according to claim 6 ,

wherein the processor:

obtains noise characteristic information including a characteristic of the first noise or noise correlation information correlated with a characteristic of the first noise; and

identifies the quiet area according to the ratio and the noise characteristic information.

11. The unmanned aircraft according to claim 6 ,

wherein the processor:

obtains a position of a sound processing target of the sound processing device; and

notifies the sound processing target to enter the quiet area.

12. The unmanned aircraft according to claim 6 ,

wherein the processor:

obtains a position of a sound processing target of the sound processing device;

obtains a movement instruction for moving the unmanned aircraft; and

controls at least one of a position and an attitude of the unmanned aircraft to include the sound processing target of the sound processing device in the quiet area while moving the unmanned aircraft based on the movement instruction.

13. The unmanned aircraft according to claim 6 ,

wherein the sound processing device is a loudspeaker,

a sound processing target of the sound processing device is a sound output target, and

the processor:

obtains a characteristic of a second noise coming from a position of the sound output target; and

causes the loudspeaker to output, toward the quiet area, sound that reduces the second noise based on the characteristic of the second noise.

14. The unmanned aircraft according to claim 6 , further comprising:

a mechanism that adjusts the ratio,

wherein the processor:

obtains a position of a sound processing target of the sound processing device; and

controls the mechanism to adjust the ratio to include the sound processing target in the quiet area.