Method for amplifying sound using unmanned aerial vehicles, public address system, and unmanned aerial vehicles equipped with public address devices

Abstract

To convey voice more surely to people in a target area.SOLUTION: A method for amplifying voice in a target area includes the steps of: acquiring environmental information on the target area; determining a flying route of an unmanned flight body having a voice amplification device on the basis of the correlation between the environmental information and the voice amplification range of the target area; and executing the flight of the unmanned flight body in the determined flying route.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to a method for amplifying sound using an unmanned aerial vehicle, a public address system, and an unmanned aerial vehicle equipped with a public address device. [Background technology]

[0002] It is known to use unmanned aerial vehicles such as drones to guide people to safety in disaster-stricken areas in order to facilitate their evacuation. For example, Patent Document 1 discloses an aerial vehicle that includes a flight unit that flies the vehicle itself, an acquisition unit that acquires disaster prevention information indicating the occurrence of an event that may cause a disaster and the area affected by the disaster, a determination unit that determines a flight path for flying through the area indicated by the acquired disaster prevention information, a control unit that performs flight control for flight along the determined flight path when an instruction to start flight is received, and a notification unit that issues a notification regarding the disaster indicated by the acquired disaster prevention information during flight control. The aerial vehicle acquires disaster prevention information indicating the disaster and the area where the disaster will occur. The aerial vehicle flies through the area and emits audio such as evacuation instructions from a speaker. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6903554 Summary of the Invention [Problem to be solved by the invention]

[0004] The range over which sound can be transmitted from a speaker varies depending on various factors, so there is a possibility that necessary information may not be sufficiently conveyed to people in the target area where the sound should be transmitted.

[0005] In view of the above, the object of the present disclosure is to provide a method for amplifying sound using an unmanned aerial vehicle, a public address system, and an unmanned aerial vehicle equipped with a public address device, which are effective in more reliably transmitting sound to people in a target area. [Means for solving the problem]

[0006] In order to solve the above problem, according to one aspect of the present disclosure, a method for amplifying sound in a target area includes the steps of acquiring environmental information about the target area, determining a flight route of an unmanned aerial vehicle equipped with a sound amplification device based on the correlation between the environmental information and the amplification range in the target area, and flying the unmanned aerial vehicle along the determined flight route.

[0007] According to another aspect of the present disclosure, a public address system for amplifying sound in a target area includes an environmental information acquisition unit, a flight route determination unit, and a communication unit. The environmental information acquisition unit acquires environmental information related to the target area. The flight route determination unit determines a flight route for an unmanned aerial vehicle equipped with a public address device based on a correlation between the environmental information and a sound amplification range in the target area. The communication unit transmits the determined flight route to the unmanned aerial vehicle.

[0008] According to yet another aspect of the present disclosure, an unmanned aerial vehicle that amplifies audio in a target area includes a wireless communication device, a control device, and a loudspeaker. The wireless communication device receives a flight route determined based on a correlation between environmental information about the target area and an amplification range in the target area. The control device executes flight of the unmanned aerial vehicle according to the determined flight route. The loudspeaker amplifies audio during flight of the unmanned aerial vehicle. [Effects of the Invention]

[0009] The public address method using an unmanned aerial vehicle, the public address system, and the unmanned aerial vehicle equipped with a public address device according to the present disclosure are effective in more reliably transmitting sound to people in a target area. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 shows an example of the overall configuration of a public address system according to the present disclosure. [Figure 2] FIG. 2 shows an example of the configuration of the management device and the control terminal according to the present disclosure. [Figure 3]FIG. 3 shows a front view of an unmanned aerial vehicle according to the present disclosure. [Figure 4] FIG. 4 shows an example configuration of an unmanned aerial vehicle according to the present disclosure. [Figure 5] FIG. 5 is a flowchart showing the operation of the loudspeaker system according to the first embodiment. [Figure 6A] FIG. 6A is a diagram for explaining a flight route of the unmanned aerial vehicle according to the first embodiment. [Figure 6B] FIG. 6B is a diagram for explaining the flight route of the unmanned aerial vehicle according to the first embodiment. [Figure 7A] FIG. 7A shows an example of flight route information for an unmanned aerial vehicle according to the present disclosure. [Figure 7B] FIG. 7B shows another example of flight route information for an unmanned aerial vehicle according to the present disclosure. [Figure 8] FIG. 8 is a flowchart showing the operation of the loudspeaker system according to the second embodiment. [Figure 9A] FIG. 9A is a diagram for explaining a flight route of an unmanned aerial vehicle according to the second embodiment. [Figure 9B] FIG. 9B is a diagram for explaining a flight route of an unmanned aerial vehicle according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, more detailed description than necessary may be omitted. For example, detailed description of well-known matters or redundant description of substantially identical configurations may be omitted. This is to avoid unnecessary redundancy in the following description and to facilitate understanding by those skilled in the art. Note that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter recited in the claims.

[0012] In the following description, "target area" refers to the area in which the target sound is amplified. "Amplified range" refers to the range in the target area in which sound can be transmitted from a loudspeaker or speaker. The range in which sound can be transmitted does not simply refer to the range in which sound can be heard, but also refers to the range in which a person can generally clearly hear the sound. Hereinafter, each embodiment of the present invention will be described.

[0013] 1. First Embodiment It is known that evacuation information, warnings, and other announcements are broadcast from large speakers installed outdoors. Large speakers installed outdoors are set up so that the sound can be transmitted to the target area. However, it is difficult to install large speakers so that the sound can be transmitted to all target areas. In addition, the range and speed at which the sound can be transmitted changes from moment to moment depending on changes in the environment of the target area.

[0014] In this embodiment, the sound amplification range of outdoor speakers (hereinafter referred to as fixed speakers) installed in the target area is predicted in correlation with environmental information. The purpose is to more reliably transmit sound in the target area by flying an unmanned aerial vehicle equipped with a speaker in parts of the target area where the sound amplification range can no longer be covered, i.e., where sound from the fixed speakers cannot be transmitted or cannot be clearly heard.

[0015] 1-1.Configuration 1-1-1. Public address system configuration 1 shows a schematic diagram of the overall configuration of a public address system 1 according to this embodiment. The public address system 1 includes a management device 10 and a control terminal 30 that can communicate with the management device 10 via a network N. The public address system 1 may further include an unmanned aerial vehicle 50 that can wirelessly communicate with the control terminal 30 and whose flight is controlled by the control terminal 30.

[0016] The management device 10 instructs the control terminal 30 on the flight route of the unmanned aerial vehicle 50 and instructs the control terminal 30 on the audio content to be amplified. The control terminal 30 receives the flight route from the management device 10 and automatically or manually instructs the unmanned aerial vehicle 50 to fly along the flight route and instructs the unmanned aerial vehicle 50 to amplified the audio content. The unmanned aerial vehicle 50 amplified the audio content from a speaker while flying according to the flight route received from the control terminal 30. The network N includes a wired LAN (Local Area Network), a wireless LAN, a WAN (Wide Area Network), and / or the Internet, etc.

[0017] 1-1-2. Management device configuration The management device 10 shown in FIG. 2 is a computer device that functions as a server or the like, and includes a control unit 11, a storage unit 12, and a communication unit 19. The control unit 11 is an electronic circuit such as a CPU (Central Processing Unit). The control unit 11 operates as an arithmetic processing device and control device, and controls the management device 10 according to various programs to execute the functions described below. The storage unit 12 is a read-only memory (ROM), a random access memory (RAM), a hard disk drive (HDD), a solid state drive (SSD), a ferroelectric random access memory (FeRAM), or the like. The ROM, HDD, SSD, FeRAM, or the like stores programs, calculation parameters, calculation results, and the like used by the control unit 11. The RAM temporarily stores programs used in executing the functions of the control unit 11, parameters that change as appropriate during the execution, and the like. The communication unit 19 (an example of a communication unit) is, for example, a network interface card for connecting to a wired LAN or the Internet. The communication unit 19 may be a wireless communication interface for connecting to a base station or a communication interface compatible with a wireless LAN.

[0018] The management device 10 is connected to a flight route information storage device 70, which will be described later. The flight route information storage device 70 is configured with a HDD, semiconductor memory, etc. The flight route information storage device 70 may be directly connected to the management device 10, or may be connected via a communication unit 19 over a LAN or the Internet.

[0019] The control unit 11 executes the programs read from the storage unit 12 to thereby perform the functions of an audio content acquisition unit 111, an environmental information acquisition unit 112, a flight route determination unit 113, and a flight route instruction unit 114.

[0020] The audio content acquisition unit 111 acquires audio content to be amplified from the speaker of the unmanned aerial vehicle 50 (described later) and transmits it to the control terminal 30 via the communication unit 19. The audio content may be acquired from an external database or server via the communication unit 19 and the network N. Alternatively, the audio content may be input via an input device (not shown) connected to the management device 10. The input device may be, for example, a microphone, keyboard, touch panel, etc. The audio content may include, for example, disaster information, disaster prevention information, evacuation instructions, advertisements, and guidance of people flow in places where many people gather.

[0021] The environmental information acquisition unit 112 (an example of an environmental information acquisition unit) acquires environmental information of the target area and / or the vicinity of the target area. The environmental information acquisition unit 112 may acquire the environmental information by connecting to an external server managed by the Japan Meteorological Agency or a company that provides weather information via the communication unit 19 and the network N. Alternatively, the environmental information acquisition unit 112 may acquire the environmental information inputted by an input device.

[0022] Environmental information is information that affects the transmission of sound when it changes, and is correlated with the amplification range. Examples of environmental information include meteorological information such as wind speed, wind direction, temperature, humidity, and weather. Wind speed, for example, indicates the average wind speed over a given period of time (e.g., 10 minutes) at a given height above the ground. Wind speed and wind direction are known to affect sound transmission. Specifically, sounds traveling in the same direction as the wind, i.e., sounds from upwind, are refracted toward the ground due to the difference between the slow wind speed at low altitudes near the ground and the fast wind speed at high altitudes away from the ground. This makes the sounds easier to hear. On the other hand, sounds traveling against the wind, i.e., sounds from downwind, are refracted toward the sky and are therefore harder to hear.

[0023] It is known that temperature affects sound attenuation. For example, during the day, solar radiation warms the ground, increasing the speed of sound near the surface, causing sound to refract upward and making it more difficult to transmit. On the other hand, at night, radiative cooling lowers the temperature near the surface, causing sound to bend downward and making it easier to transmit. Humidity affects sound attenuation due to the viscosity and molecular absorption of air, which is the medium through which sound travels. Weather can be used in addition to humidity and temperature parameters, or as a separate parameter from humidity and temperature.

[0024] The flight route determination unit 113 (an example of a flight route determination unit) determines the flight route of the unmanned aerial vehicle 50 based on the acquired environmental information. Specifically, the flight route determination unit 113 determines the flight route by referring to the flight route information storage device 70.

[0025] 7A and 7B show examples of tables showing flight route information 71, 72 stored in the flight route information storage device 70. Flight route information 71, 72 is generated for each target area in which a fixed speaker 90 is installed. Identification information for the installation area is stored in association with identification information for the fixed speaker. In FIG. 7A, a flight route is set according to a combination of wind speed and wind direction as environmental information. The flight route is set using latitude, longitude, altitude, and the like. For example, as shown in FIG. 6A, the flight route is the range indicated by 200 where the amplification range of fixed speakers 90a, 90b covers the target area 100. If the wind speed is 1.5 m / s or less, a flight route R000 is determined that is not covered by the amplification range 200. The flight route includes not only the route along which the unmanned aerial vehicle 50 moves within a specified area, but also the route along which the unmanned aerial vehicle 50 hoveres at a specified position.

[0026] The sound amplification range 200 of the fixed speaker 90 is calculated according to each environmental information, taking into consideration characteristic information of the fixed speaker 90 (output sound pressure level, frequency characteristics, installation direction, etc.) and the specific installation environment (for example, a coastal area, an area with many high-rise buildings, a mountainous area, etc.). The flight route is set in a target area that cannot be covered by the sound amplification range 200 of the fixed speaker 90 due to changes in the environment.

[0027] Note that the flight route information 71, 72 may include, instead of the flight route itself, the calculated amplification range of the fixed speaker 90. The management device 10 or the control terminal 30 may calculate and determine the flight route based on the amplification range.

[0028] The flight route instruction unit 114 transmits the determined flight route via the communication unit 19 to the control terminal 30, which will be described next.

[0029] 1-1-3. Control terminal configuration The control terminal 30 shown in FIG. 2 is a computer device for controlling the unmanned aerial vehicle 50 via wireless communication and includes a control unit 31, a memory unit 32, an input unit 36, a display unit 37, and a wireless communication unit 39. The control unit 31 is an electronic circuit such as a CPU and operates as an arithmetic processing unit and a control device. The control unit 31 controls the control terminal 30 according to various programs to execute the functions described below. The memory unit 32 is a semiconductor memory such as ROM, RAM, or flash memory. The ROM and flash memory store programs, calculation parameters, calculation results, etc. used by the control unit 31. The RAM temporarily stores programs used to execute the functions of the control unit 31 and parameters that change as appropriate during execution. The input unit 36 includes a joystick, buttons, or a touch panel, and controls the flight of the unmanned aerial vehicle 50 through input operations by the pilot. The input unit 36 also accepts inputs for controlling the direction of the speaker, microphone, and camera installed on the unmanned aerial vehicle 50. The display unit 37 is composed of a liquid crystal display device or an organic EL display device. The display unit 37 displays information about the flight route received from the management device 10 and the route currently being flown. The display unit 37 also displays videos and images captured by the camera of the unmanned aerial vehicle 50.

[0030] The wireless communication unit 39 (an example of a communication unit) may be, for example, a wireless communication interface for connecting to a base station, or may be a communication interface compatible with a wireless LAN.

[0031] The control unit 31 executes the functions of the flight instruction unit 311 and the loudspeaker instruction unit 312 by executing a program read from the memory unit 32. The flight instruction unit 311 transmits flight instructions according to the flight route received from the management device 10 to the unmanned aerial vehicle 50. The loudspeaker instruction unit 312 transmits audio content received from the management device 10 to the unmanned aerial vehicle 50.

[0032] 1-1-4.Configuration of unmanned aerial vehicles FIG. 3 shows the front appearance of the unmanned aerial vehicle 50, and FIG. 4 shows an example of the overall configuration of the unmanned aerial vehicle 50. The unmanned aerial vehicle 50 is an unmanned aircraft that can be remotely or automatically controlled, and performs flight operations such as ascending, moving forward, rotating, and descending in response to flight commands from the control terminal 30. The unmanned aerial vehicle 50 comprises a main body 50a, multiple arms 50b extending horizontally and radially from the main body 50a, multiple legs 50c extending downward, and rotors 55 attached to the upper ends of each leg 50c. The unmanned aerial vehicle 50 flies using lift generated by rotating the rotors 55 using the rotation of a motor 56. The unmanned aerial vehicle 50 also generates a reaction by changing the rotation direction of some of the rotors 55, preventing the main body 50a itself from rotating. A speaker 62 is attached to the main body 50a of the unmanned aerial vehicle 50, facing downward. The speaker 62 (an example of a public address device) amplifies sound while the unmanned aerial vehicle 50 is flying. The angle of the speaker 62 can be changed in the up and down directions indicated by the arrows by the speaker direction control mechanism 61. This allows the direction in which the speaker 62 amplifies sound to be changed downward or forward and backward.

[0033] As shown in FIG. 4, the unmanned aerial vehicle 50 is equipped with a control device 51, a storage device 52, a group of sensors 53, a GPS receiver 54, a battery 58, and a wireless communication device 59 as components for flight. The control device 51 is an electronic circuit such as a CPU, and functions as an arithmetic processing device and a control device. The control device 51 controls the unmanned aerial vehicle 50 according to various programs to execute the functions described below. The storage device 52 is a memory such as a ROM, RAM, or flash memory. The ROM and flash memory store programs, calculation parameters, calculation results, etc. used by the control device 51. The RAM temporarily stores programs used in executing the functions of the control device 51, parameters that change as appropriate during that execution, etc.

[0034] The sensor group 53 includes an acceleration sensor and an angular velocity sensor that detect acceleration and angular velocity for purposes such as attitude control of the unmanned aerial vehicle 50, an air pressure sensor for detecting the altitude of the unmanned aerial vehicle 50, and a geomagnetic sensor for detecting the orientation of the unmanned aerial vehicle 50. The GPS receiver 54 includes an antenna and a signal processing unit, and receives signals from GPS satellites to detect position information of the unmanned aerial vehicle 50. The battery 58 stores the power required to operate the unmanned aerial vehicle 50 and supplies it to each component. The wireless communication device 59 (an example of a wireless communication device) includes a wireless communication interface for wireless communication with the control terminal 30.

[0035] The unmanned aerial vehicle 50 further includes a microphone direction control mechanism 63, a microphone 64, a camera direction control mechanism 65, and a camera 66. The microphone 64 can change its sound collection direction by changing its angle in the vertical direction using the microphone direction control mechanism 63, similar to the speaker 62. The camera 66 can change its shooting direction by changing its angle in the vertical direction using the camera direction control mechanism 65, similar to the speaker 62.

[0036] The control device 51 (an example of a control device) executes the functions of a flight control unit 511, an audio control unit 512, and an image control unit 513 by executing a program read from the storage device 52. The flight control unit 511 controls the number of rotations and the rotation speed of the motor 56 in accordance with flight instructions from the control terminal 30 to fly the unmanned aerial vehicle 50. The flight control unit 511 acquires the tilt and rotation direction of the main body 50a shown in FIG. 3 based on output data from the above-mentioned sensor group 53 and GPS receiver 54, and acquires position information including the latitude and longitude, altitude, and azimuth angle of the main body 50a during flight. The storage device 52 stores a program in which an algorithm is implemented to control the attitude and basic flight operations of the unmanned aerial vehicle 50 during flight. The program flies the unmanned aerial vehicle 50 while correcting the attitude and position of the main body 50a in accordance with flight instruction signals transmitted from the control terminal 30. The unmanned aerial vehicle 50 may be manually controlled by a pilot using the control terminal 30, or may be flown autonomously along a flight route transmitted from the control terminal 30.

[0037] The audio control unit 512 amplifies audio content transmitted from the control terminal 30 and received via the wireless communication device 59 through the speaker 62. The audio control unit 512 controls the speaker direction control mechanism 61 to point the speaker 62 in a desired direction. The audio control unit 512 also transmits audio collected by the microphone 64 to the control terminal 30 via the wireless communication device 59. The image control unit 513 temporarily stores videos and images captured by the camera 66 in the storage device 52 and transmits them to the control terminal 30 via the wireless communication device 59.

[0038] 1-2.Operation The operation of the public address system 1 and the unmanned aerial vehicle 50 shown in FIGS. 1 to 4 will be described with reference to FIGS. 5 to 7A. When the broadcast of audio content from the fixed speakers 90a and 90b shown in FIG. 6A is started, the control unit 11 of the management device 10 identifies the installation area associated with the identification information of the fixed speakers 90a and 90b that will start broadcasting (S101). Here, "broadcasting starts" does not necessarily mean that the broadcast actually starts, but also includes the time before the broadcast starts or when preparations for broadcasting are underway. The environmental information acquisition unit 112 of the management device 10 acquires environmental information for the identified installation area via the communication unit 19 (S102). Here, as an example, wind speed and wind direction are acquired from external weather information. The flight route determination unit 113 of the management device 10 references the flight route information 71 shown in FIG. 7A (S103) and determines a flight route corresponding to the acquired wind speed and wind direction (S104). Here, it is assumed that the wind speed is 1.5 m / s or less and there is no wind direction. Flight route determination unit 113 determines flight route R000. Flight route instruction unit 114 of management device 10 transmits flight route R000 (FIG. 6A) to control terminal 30 via communication unit 19. In addition, audio content acquisition unit 111 of management device 10 transmits the audio content to be amplified to control terminal 30 via communication unit 19 (S105).

[0039] In the control terminal 30, the flight route and audio content received via the wireless communication unit 39 are processed by the flight instruction unit 311 and the audio amplification instruction unit 312, respectively. Flight of the unmanned aerial vehicle 50 and amplification of the audio content are performed in accordance with these instructions (S106). Specifically, the unmanned aerial vehicle 50 receives instructions including the flight route from the control terminal 30 via the wireless communication device 59. The flight control unit 511 controls the rotation of the motor 56 based on data from the sensor group 53 and the GPS receiver 54, and performs flight along the instructed flight route. At the same time, the audio content received from the speaker 62 is amplified. If the broadcast is to end, the process ends (S107).

[0040] Features The public address method, public address system 1, or unmanned aerial vehicle 50 using the unmanned aerial vehicle 50 according to the above-described embodiment flies the unmanned aerial vehicle 50 and amplifies sound in the target area 100 to compensate for any shortcomings in the public address range 200 of the fixed speaker 90, based on the correlation between environmental information about the target area 100 and the public address range 200 of the fixed speaker 90, which changes depending on the environmental information. This allows sound to be more reliably transmitted to people in the target area 100, making it possible to more reliably issue evacuation instructions, guide people, etc.

[0041] 1-4. Variations The management device 10 may determine the flight route of the unmanned aerial vehicle 50 in response to changes in temperature and / or humidity. For example, the management device 10 refers to flight route information 72 shown in FIG. 7B. When the acquired temperature is above a predetermined temperature and / or above a predetermined humidity, the management device 10 determines, for example, flight route R012. As shown in FIG. 6B, the management device 10 flies the unmanned aerial vehicle 50 along flight route R012 and amplifies the audio content so as to compensate for any shortfall in the amplification range 200 of the fixed speaker 90 relative to the target area 100 that has changed due to temperature and / or humidity.

[0042] 2. Second Embodiment In the second embodiment, the management device 10 changes the flight route of the unmanned aerial vehicle 50 during flight in response to changes in environmental information.

[0043] 2-1.Configuration The configuration of the loudspeaker system according to this embodiment is similar to that of the loudspeaker system 1 shown in FIGS. 1 to 4, and therefore a description thereof will be omitted and similar reference numerals will be used.

[0044] 2-2.Operation The operation of the loudspeaker system 1 according to this embodiment will be described with reference to Figures 7A to 8. Steps S111 to S113 are the same as steps S101 to S103 shown in Figure 5. Here, it is assumed that wind speed and wind direction are acquired from external weather information as an example of environmental information. The flight route determination unit 113 of the control unit 11 of the management device 10 refers to the flight route corresponding to the acquired wind speed and wind direction, and determines whether a change in the flight route is necessary (S114).

[0045] For example, as shown in FIG. 9A, assume that while unmanned aerial vehicle 50 is flying flight route R000 to compensate for a lack of amplification range 200 of fixed speaker 90 in target area 100, there is a change in environmental information, i.e., the wind direction (arrow W) changes from 1.5 m / s or less to a northeasterly direction with a predetermined wind speed or greater. Based on the flight route information referenced in step S113, flight route determination unit 113 changes flight route R000 to flight route R005 (S115). On the other hand, if the wind speed is 1.5 m / s or less, the flight route determination unit 113 does not change the flight route because it is the same as the current flight route R000, and proceeds to step S118.

[0046] The flight route instruction unit 114 of the control unit 11 of the management device 10 transmits the flight route R005 to the control terminal 30 via the communication unit 19 (S116). Furthermore, the audio content acquisition unit 111 transmits the audio content to be amplified to the control terminal 30 via the communication unit 19 as necessary (S116). As in the first embodiment, the control terminal 30 executes flight of the unmanned aerial vehicle 50 in accordance with the flight instructions and the amplified audio instructions (S117). If the broadcast has ended, the processing ends, and if not, the processing returns to step S112 (S118). The management device 10 acquires environmental information at predetermined time intervals and changes the flight route of the unmanned aerial vehicle 50 in accordance with changes in the environmental information (S112 to S118).

[0047] As in the first embodiment, the management device 10 may change the flight route of the unmanned aerial vehicle 50 in response to changes in temperature and / or humidity as environmental information.

[0048] Features In the public address system 1 according to this embodiment, in addition to the features of the first embodiment, the flight route of the unmanned aerial vehicle 50 is changed in response to changes in environmental information. Therefore, the flight route of the unmanned aerial vehicle 50 can be dynamically changed in response to ever-changing environmental information, so that sound can be transmitted more reliably in the target area 100.

[0049] 3. Other embodiments As described above, each embodiment has been described as an example of the technology disclosed in this application. However, the technology in this disclosure is not limited to this, and can be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made as appropriate. Furthermore, it is also possible to combine the components described in the above embodiments to create new embodiments. For example, the following embodiments are possible.

[0050] (1) The environmental information may be information indicating a power outage, the size of the flow of people, the density of people, etc., within the target area. A power outage affects the normal operation of the fixed speakers 90 within the target area, and is therefore environmental information that correlates with the amplification range. Information about power outages within the target area is obtained, for example, from an external information source. The larger the flow of people and the density of people, the more difficult it is for sound to propagate, and so this is environmental information that correlates with the amplification range. Information indicating the size of the flow of people and the density of people is obtained, for example, from an external information source. Alternatively, information indicating the size of the flow of people and the density of people may be obtained by analyzing image data transmitted in real time from the camera 66 (Figure 4) of the unmanned aerial vehicle 50.

[0051] Based on this information, for example, as shown in Figure 9B, if it is predicted that the flow of people within an area that is both the target area 100 and the amplification range 200 of the fixed speaker 90 will move in the direction of arrow F and reach outside the amplification range 200, the management device 10 controls the unmanned aerial vehicle 50 to fly along flight route R021.

[0052] (2) The environmental information may be information indicating noise within the target area. The louder the noise in the target area, the more difficult it is for the sound to propagate, so this environmental information correlates with the amplification range. The information indicating noise may be obtained, for example, from an external information source. Alternatively, the information indicating noise may be obtained by analyzing audio data transmitted in real time from the microphone 64 (Figure 4) of the unmanned aerial vehicle 50. Wind speed may be used as a parameter indicating noise caused by strong winds, etc. The intensity of precipitation, such as heavy rain, may be used as a parameter indicating noise.

[0053] For example, as shown in FIG. 6B, the management device 10 controls the unmanned aerial vehicle 50 to fly along flight route R012 to compensate for the shortfall in the amplification range 200 of the fixed speaker 90 relative to the target area 100 caused by noise.

[0054] (3) The environmental information may be information indicating a malfunction or abnormality of the fixed speaker 90. If the fixed speaker 90 has an abnormality or malfunction, it may be difficult to hear the sound from the fixed speaker 90 in the target area 100, or the sound may not be output at all. In this case, for example, the management device 10 acquires information indicating the sound status, wiring status, amplifier abnormality, etc. of the speaker 90, and identifies the installation area of the speaker 90. The unmanned aerial vehicle 50 is flown along a flight route set in the target area 100 of the speaker 90 within the amplification range 200 during normal operation. This allows the unmanned aerial vehicle 50 to fly so as to compensate for any shortfall in the amplification range 200 of the fixed speaker 90 that has changed due to the malfunction or abnormality. (4) In the public address system 1 according to the above embodiment, the management device 10 flies the unmanned aerial vehicle 50 to compensate for the lack of the amplification range of the fixed speaker 90, but this is not limited to this. The flight of the unmanned aerial vehicle 50 may be controlled to change the flight route in response to a change in the amplification range of the speaker 62 (FIG. 4) of the unmanned aerial vehicle 50 flying in the target area 100 due to a change in environmental information. (5) The unmanned aerial vehicle 50 flown to cover the sound amplification range is not limited to one unit, but may be multiple unmanned aerial vehicles 50.

[0055] (6) In the above embodiment, the flight route information 71, 72 (FIGS. 7A and 7B) stored in the flight route information storage device 70 (FIG. 2) may be generated based on the speaker's amplification range predicted using AI (Artificial Intelligence). For example, along with environmental information such as meteorological information, the characteristics of the area (e.g., a coastal area, an area with many high-rise buildings, a mountainous area, etc.), the climate, the season, the time of broadcast, etc. may be input as learning data, and machine learning may be used to predict the speaker's amplification range, which changes depending on the environmental information, and the corresponding flight route of the unmanned aerial vehicle 50.

[0056] (7) The public address system 1 according to the above embodiment includes a control terminal 30, but is not limited to this. The public address system 1 may be configured to instruct the unmanned aerial vehicle 50 to fly directly from the management device 10. Specifically, the management device 10 may be disposed as part of the control system for the unmanned aerial vehicle 50, and the unmanned aerial vehicle 50 may automatically fly along a determined flight route through remote communication via the communication unit 19.

[0057] In the above embodiment, the audio content may be input from the control terminal 30 via an input means such as a microphone, instead of being transmitted from the management device 10, or may be pre-stored in the memory unit 32 by another method. (8) In the above embodiment, the audio content to be amplified may be Japanese audio content or audio content in a language other than Japanese. The audio content may also include Japanese audio content and audio content in a language other than Japanese. In this case, the audio content in the other language may be amplified together with the Japanese audio content.

[0058] (9) In the above embodiments, each device or system may have a cloud computing configuration in which a single function is shared and processed jointly by multiple devices via a network. In the above embodiments, the term "device" or "system" includes cases where it means a collection of multiple components (devices, modules (components), etc.), regardless of whether all the components are in the same housing. In addition, multiple devices housed in separate housings and connected via a network, and a single device housed in a single housing with multiple modules, may both be called a system.

[0059] Each step described in the above flowchart can be executed by one device or can be shared and executed by multiple devices. Furthermore, if one step includes multiple processes, the multiple processes included in that one step can be executed by one device or can be shared and executed by multiple devices.

[0060] (10) In the above embodiments, the control unit or control device of each device or equipment may include a processor configured with a dedicated electronic circuit designed to realize a predetermined function according to the function required for each device or equipment. Furthermore, the control unit or control device can be realized by various processors or electronic circuits such as a CPU, an MPU, a GPU, a DSP, an FPGA, an ASIC, etc. The control unit or control device may be configured with one or more processors.

[0061] Part or all of the memory unit or storage device of each device or equipment may be composed of any computer-readable recording medium, such as an optical disk, magnetic disk, magneto-optical disk, magnetic tape, HDD, SD card, SSD, etc., depending on the functions required for each device or equipment.

[0062] The communication unit or communication device of each device or equipment may be any communication interface, such as a wireless LAN, a wired LAN, 3G (3rd Generation), LTE (Long Term Evolution), 4G (4th Generation), 5G (5th Generation), or a millimeter wave wireless communication interface, depending on the functions required for each device or equipment.

[0063] The computer program is not limited to one recorded on a recording medium, but may be one acquired via a telecommunications line, a wireless or wired communication line, a network such as the Internet, or the like.

[0064] Each process in the above-described embodiments may be realized by hardware or software (including cases where it is realized together with an OS (operating system), middleware, or a predetermined library). Furthermore, each process may be realized by a combination of software and hardware.

[0065] The order of execution of operations of the system, device or equipment in the above embodiments is not necessarily limited to the description of the above embodiments, and the order of execution can be changed or multiple operations can be executed simultaneously within the scope of the gist of the invention. [Industrial Applicability]

[0066] The present disclosure is applicable to outdoor sound amplification methods and systems, and unmanned aerial vehicles equipped with sound amplification devices. [Explanation of symbols]

[0067] 1: Public address system 10: Management device 11: Control section 12: Storage section 19: Communications Department 30: Control terminal 31: Control unit 32: Storage section 36: Input section 37:Display section 39: Wireless communication unit 50: Unmanned aerial vehicle 50a: Main body 50b: Arm 50c: Legs 51: Control device 52: Storage device 53: Sensor group 54: GPS receiver 55: Rotor 56: Motor 58: Battery 59: Wireless communication device 61: Speaker direction control mechanism 62: Speaker 63: Microphone direction control mechanism 64:Mike 65: Camera direction control mechanism 66: Camera 70: Flight route information storage device 71, 72: Flight route information 90, 90a, 90b: Fixed speakers 100: Target area 111: Audio content acquisition unit 112:Environmental information acquisition department 113: Flight route determination unit 114: Flight route indicator 200: Amplification range 311:Flight instruction department 312: Public address and control section 511: Flight control unit 512: Audio control section 513: Image control unit

Claims

1. A method for amplifying sound in a target area, comprising: obtaining environmental information about the area of interest; determining a sound amplification range of a fixed speaker installed to amplify sound in the target area based on characteristic information of the fixed speaker, an installation environment, and the environmental information; determining a flight route for the unmanned aerial vehicle in a target area that cannot be covered by the sound amplification range of the fixed speaker; A step of flying the unmanned aerial vehicle along the determined flight route; A sound amplification method comprising:

2. The sound amplification method according to claim 1 , further comprising the step of changing a flight route of the unmanned aerial vehicle in accordance with the environmental information.

3. 3. The sound amplification method according to claim 1, wherein the environmental information is information indicating at least one of wind speed, wind direction, temperature, humidity, and weather in or near the target area.

4. The sound amplification method according to claim 1 , wherein the environmental information is information indicating at least one of a power outage, a flow of people, a density of people, and noise in the target area.

5. A public address system for amplifying sound in a target area, comprising: an environmental information acquisition unit that acquires environmental information about the target area; a flight route determination unit that determines the amplification range of a fixed speaker installed to amplify sound in the target area based on characteristic information of the fixed speaker, the installation environment, and the environmental information, and determines a flight route of the unmanned aerial vehicle to parts of the target area that cannot be covered by the amplification range of the fixed speaker; a communication unit that transmits the determined flight route to the unmanned aerial vehicle; A public address system comprising:

6. An unmanned aerial vehicle that amplifies sound in a target area, a wireless communication device that receives a flight route set for a portion of the target area that cannot be covered by the amplification range of a fixed speaker, the flight route being determined based on characteristic information of the fixed speaker installed to amplify sound in the target area, the installation environment, and environmental information related to the target area; and a control device that executes flight of the unmanned aerial vehicle according to the determined flight route; a loudspeaker device that amplifies sound during flight of the unmanned aerial vehicle; An unmanned aerial vehicle equipped with

Images