Driving management system

Abstract

To provide a driving management system that can acquire clear voice from one or more microphones selected according to the situation from among multiple microphones of a recording device such as a drive recorder.SOLUTION: A driving management system 1 includes: a plurality of microphones 26 mounted on a vehicle to input detected audio; a microphone processor 24 that receives inputs from the plurality of microphones 26; a control unit 11 that generates a control signal to adjust the detection sensitivity of at least one of the plurality of microphones 26 to be higher than that of the other microphones 26 when a predetermined priority condition is satisfied; and a microphone control unit 25 connected to each of the plurality of microphones 26 to adjust the detection sensitivity of the plurality of microphones 26 based on the control signal.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to an operation management system.

Background Art

[0002] Conventionally, in order to assist safe driving, in-vehicle devices such as a drive recorder have been mounted on vehicles such as automobiles and railways (see, for example, Patent Document 1). A drive recorder collects image information (video information) captured by an in-vehicle camera and audio information input to an in-vehicle microphone, and records the collected image information and audio information on a recording medium such as an internal memory or a memory card. More specifically, many drive recorders mounted on vehicles collect image information and audio information acquired in a time period before and after the occurrence of a trigger, such as a shock greater than a certain level, a sudden start, a sudden brake, or a sudden turn, as operation information using the trigger.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] Generally, as audio information acquired by a drive recorder, only the audio inside the vehicle is used, but there are cases where it is desirable to acquire not only the audio inside the vehicle but also the audio outside the vehicle and in the cargo bed (cargo compartment). In such a case, it is conceivable to mount microphones both inside and outside the vehicle (in the cargo bed) and control the audio of these microphones by a single processing unit so that the audio inside and outside the vehicle is acquired simultaneously. However, in this method, there is a possibility that the audio inside the vehicle becomes difficult to hear due to the audio outside the vehicle.

[0005] On the other hand, Patent Document 2 discloses a system including a selection unit that selects one microphone from a plurality of microphones according to a predetermined type of algorithm, whereby clear audio is obtained from one of the plurality of microphones. However, with this method, audio cannot be obtained simultaneously from a plurality of microphones.

[0006] The present invention has been made in view of the above-described situation, and an object thereof is to provide an operation management system capable of obtaining clear audio from one or more microphones selected according to the situation among a plurality of microphones in a recording device such as a drive recorder.

Means for Solving the Problems

[0007] In order to achieve the above-described object, the operation management system according to the present invention is characterized by the following. A plurality of microphones mounted on a vehicle and inputting detected audio, A microphone processing unit that receives inputs from the plurality of microphones, A control unit that generates a control signal for adjusting the detection sensitivity of at least one of the plurality of microphones to be higher than the detection sensitivity of the other microphones when a predetermined priority condition is satisfied, A microphone control unit that is connected to each of the plurality of microphones and adjusts the detection sensitivity of the plurality of microphones based on the control signal, An operation management system.

Effects of the Invention

[0008] According to the present invention, when a predetermined priority condition is satisfied, the control unit generates a control signal for adjusting the detection sensitivity of at least one microphone among a plurality of microphones to be higher than the detection sensitivity of other microphones. Thereby, the present invention eliminates the possibility that necessary voices are difficult to hear or clear voices can be obtained only from one selected microphone as in the prior art. That is, according to the present invention, clear voices can be obtained from one or a plurality of microphones selected according to the situation among a plurality of microphones.

[0009] The present invention has been briefly described above. Furthermore, the details of the present invention will be further clarified by reading through the embodiments for carrying out the invention described below (hereinafter referred to as "embodiments") with reference to the accompanying drawings.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0011] Specific embodiments of the present invention will be described below with reference to each figure.

[0012] The operation management system 1 is for a drive recorder used while mounted on a vehicle, and is for acquiring clear audio from one or more selected microphones 26 according to the situation (when a predetermined priority condition is satisfied). It includes an in-vehicle unit 10, a plurality of microphone control units 25, and a plurality of microphones 26 (see Fig. 1).

[0013] In the operation management system 1, a device including the in-vehicle unit 10, a plurality of microphone control units 25, a plurality of microphones 26, and an in-vehicle camera (not shown) can be referred to as a drive recorder. Note that the drive recorder collects image information (video information) and audio acquired during a time period before and after the occurrence of a trigger, with the trigger being a shock of a certain level or more, sudden acceleration, sudden braking, sudden turning, etc. The collected audio is recorded on an internal recording medium, an office PC 30 (see Fig. 1), an external server (not shown), etc.

[0014] The in-vehicle unit 10 is mounted on the vehicle, performs an outgoing process for the vehicle driver, and collects and records operation data such as the in-out time, travel distance, travel time, travel speed, speed over, engine speed over, sudden acceleration, sudden acceleration, sudden deceleration, etc.

[0015] The in-vehicle unit 10 has a control unit 11, a sensor I / F 12, a SW input unit 13, a card I / F 14, a volatile memory 15, a non-volatile memory 16, an external input I / F 17, a communication unit 18, a speed I / F 19, an engine I / F 20, a GPS reception unit 21, an analog I / F 22, an external output I / F 23, and a microphone processing unit 24.

[0016] The control unit 11, for example, is composed of a ROM and executes a program stored in advance, and has a function of controlling the operation of the in-vehicle unit 10, a known basic function as a drive recorder for automatically recording information such as image data (video data) captured by an in-vehicle camera (not shown) and audio input from a plurality of microphones 26, and a function of adjusting the detection sensitivity of at least one of the plurality of microphones 26 to be higher than the detection sensitivity of the other microphones 26 when a predetermined priority condition is satisfied. Based on the information input via the above-described I / F, the control unit 11 detects various operating states.

[0017] For example, an acceleration sensor (G sensor) that detects acceleration (G value) (senses impact) is connected to the sensor I / F 12, and a signal from the G sensor is input. ON / OFF signals of various buttons such as an outgoing button and an incoming button are input to the SW input unit 13.

[0018] A memory card held by the driver is removably connected to the card I / F 14. The control unit 11 records operation data, collected image information (video information), and audio on the memory card connected to the card I / F 14.

[0019] The volatile memory 15 is a semiconductor memory device capable of freely reading and writing data by accessing of the control unit 11. The volatile memory 15 is used to temporarily hold various data handled by the control unit 11. The non-volatile memory 16 stores operation programs and the like executed by the control unit 11.

[0020] An external device is connected to the external input I / F 17. The communication unit 18 performs, for example, wide-area communication. When connected to a radio base station via a mobile communication network, it communicates with an office PC 30 or a server via a network such as the Internet connected to the radio base station. Note that the office PC 30 is a PC operating with a general-purpose operating system.

[0021] The speed I / F 19 inputs vehicle speed information corresponding to speed pulses output by a vehicle speed sensor mounted on the vehicle to the control unit 11. Rotation pulses from an engine speed sensor are input to the engine I / F 20.

[0022] The GPS reception unit 21 is connected to a GPS antenna, receives signals transmitted from GPS satellites, and acquires current position information (GPS information). Signals such as those from a temperature sensor (not shown) that detects the engine temperature (coolant temperature) and a fuel quantity sensor that detects the fuel quantity are input to the analog I / F 22.

[0023] The external output I / F 23 has an external device connected thereto and outputs a signal to the external device. The microphone processing unit 24 receives inputs from a plurality of microphones 26.

[0024] The microphone control unit 25 is connected to each of the plurality of microphones 26 and adjusts the detection sensitivity of the plurality of microphones 26 based on the control signal generated by the control unit 11.

[0025] The plurality of microphones 26 are mounted, for example, inside the vehicle in which the driver of the vehicle rides, outside the vehicle, or on the vehicle's cargo bed (in the storage). That is, the plurality of microphones 26 may be considered to include an in-vehicle microphone, an out-of-vehicle microphone, and an in-storage microphone as an out-of-vehicle microphone. Note that a plurality of microphones 26 may be mounted inside the vehicle, outside the vehicle, and in the storage respectively.

[0026] Next, the operation of the operation management system 1 having the above-described configuration will be described with reference to the flowcharts shown in FIGS. 2 to 3. In this example, a case where two microphones, i.e., a first microphone which is an in-vehicle microphone and a second microphone which is an out-of-vehicle microphone, are provided will be described as an example.

[0027] In this specification, the "on state of the microphone" refers to a state where the detection sensitivity of the microphone is greater than zero, and the "off state of the microphone" refers to a state where the detection sensitivity of the microphone is zero. Also, when both the first microphone and the second microphone are in the on state, the first microphone and the second microphone have substantially equal detection sensitivities, and for example, both have their detection sensitivities set to the maximum.

[0028] When the control unit 11 detects, for example, ignition on (IG-ON) or a user operation, it starts operating, turns on the first microphone and the second microphone via the microphone control unit 25 (Sp1), and determines whether the driver (passenger) is in a break time from the acquired vehicle information (Sp2). Note that the control unit 11 acquires vehicle information from each part of the vehicle-mounted device 10 constantly or at a predetermined timing.

[0029] Next, when the control unit 11 determines that the driver is in a break time (Yes in Sp2), it turns off the first microphone and the second microphone via the microphone control unit 25 (Sp3) and proceeds to the process of Sp4. This is because when the driver is in a break time, there is no need to acquire sound inside and outside the vehicle. On the other hand, when the control unit 11 determines that the driver is not in a break time (No in Sp2), it determines whether the vehicle is in motion from the acquired vehicle information (Sp4).

[0030] Next, when the control unit 11 determines that the vehicle is in motion (Yes in Sp4), it turns on the first microphone and turns off the second microphone via the microphone control unit 25 (Sp5) and proceeds to the process of Sp6. This is because when the vehicle is in motion, it is sufficient to preferentially acquire the in-vehicle sound similar to a known drive recorder. On the other hand, when the control unit 11 determines that the vehicle is not in motion (No in Sp4), it determines whether the vehicle is backing from the acquired vehicle information (Sp6).

[0031] Next, when the control unit 11 determines that the vehicle is backing (Yes in Sp6), it turns off the first microphone and turns on the second microphone via the microphone control unit 25 (Sp7) and proceeds to the process of Sp8. This is because when the vehicle is backing, from the viewpoint of safe driving support, it is preferable to acquire the out-of-vehicle sound rather than the in-vehicle sound. On the other hand, when the control unit 11 determines that the vehicle is not backing (No in Sp6), it determines whether the vehicle is traveling on a school route from the acquired vehicle information (Sp8).

[0032] Next, when the control unit 11 determines that the vehicle is traveling on the school route (Yes in Sp8), it turns on the first microphone and the second microphone via the microphone control unit 25 (Sp9) and proceeds to the process of Sp10. This is because when the vehicle is traveling on the school route, it is preferable to acquire both the in-vehicle and out-of-vehicle voices from the perspective of safe driving support. On the other hand, when the control unit 11 determines that the vehicle is not traveling on the school route (No in Sp8), it determines whether there is a G trigger (whether acceleration has been detected) from the acquired vehicle information (Sp10).

[0033] Next, when the control unit 11 determines that there is a G trigger (Yes in Sp10), it turns on the first microphone and the second microphone via the microphone control unit 25 (Sp11) and proceeds to the process of Sp12. This is because when there is a G trigger, it is preferable to acquire both the in-vehicle and out-of-vehicle voices from the perspective of safe driving support. On the other hand, when the control unit 11 determines that there is no G trigger (No in Sp10), it determines whether there is a person in front of the vehicle from the acquired vehicle information (Sp12).

[0034] Next, when the control unit 11 determines that there is a person in front of the vehicle (Yes in Sp12), it turns on the first microphone and the second microphone via the microphone control unit 25 (Sp13) and proceeds to the process of Sp14. This is because when there is a person in front of the vehicle, it is preferable to acquire the out-of-vehicle voice rather than the in-vehicle voice from the perspective of safe driving support. On the other hand, when the control unit 11 determines that there is no person in front of the vehicle (No in Sp12), it determines whether there is a change in the vehicle state from the acquired vehicle information (Sp14).

[0035] Next, when the control unit 11 determines that there is a change in the vehicle state (Yes in Sp14), it returns to the process of Sp1. On the other hand, when it determines that there is no change in the vehicle state (No in Sp14), it temporarily ends the operation. After ending the operation, the control unit 11 starts the operation at a predetermined timing. Note that when the control unit 11 determines that there is no change in the vehicle state (No in Sp14), it may return to the process of Sp14 at a predetermined timing.

[0036] As described above regarding the operation of the operation management system 1, in this example, the determination conditions in the processes of Sp4 and Sp6 correspond to "predetermined priority conditions" (see also FIG. 4). In this example, one microphone is in the on state and the other microphone is in the off state. However, a method of adjusting the detection sensitivity of one microphone to be higher than that of the other microphone may be adopted. Also, in this example, the determination condition in the process of Sp2 corresponds to the "voice unnecessary condition" (see also FIG. 4). As the voice unnecessary condition, a case where the vehicle is in a security state, that is, parked or the like, may be considered. Also, in this example, the determination conditions in the processes of Sp8, Sp10, and Sp12 correspond to the "voice necessary conditions" (see also FIG. 4).

[0037] Next, another example of the operation of the operation management system 1 will be described with reference to the flowcharts shown in FIGS. 5 to 6. In this example, a case where a plurality of microphones including a first microphone that is an in-vehicle microphone, a second microphone that is an out-of-vehicle microphone, and a third microphone that is an in-warehouse microphone are provided will be described as an example.

[0038] When two or more microphones among the first microphone, the second microphone, and the third microphone are turned on, the two or more microphones that are turned on have substantially equal detection sensitivities, and for example, these detection sensitivities are set to the maximum.

[0039] When the control unit 11 detects, for example, ignition on (IG-ON) or a user operation, it starts operating, turns on the first microphone, the second microphone, and the third microphone via the microphone control unit 25 (Sp21), and determines whether the driver (passenger) is in a break time from the acquired vehicle information (Sp22). The control unit 11 acquires vehicle information from each part of the vehicle-mounted device 10 at all times or at a predetermined timing.

[0040] Next, when the control unit 11 determines that it is the driver's break time (Yes in Sp22), it turns off the first microphone, the second microphone, and the third microphone via the microphone control unit 25 (Sp23) and proceeds to the process of Sp24. This is because when it is the driver's break time, there is no need to acquire audio inside and outside the vehicle (including inside the warehouse). On the other hand, when the control unit 11 determines that it is not the driver's break time (No in Sp22), it determines whether the vehicle is in motion from the acquired vehicle information (Sp24).

[0041] Next, when the control unit 11 determines that the vehicle is in motion (Yes in Sp24), it turns on the first microphone and turns off the second microphone and the third microphone via the microphone control unit 25 (Sp25) and proceeds to the process of Sp26. This is because when the vehicle is in motion, it is sufficient to preferentially acquire the audio inside the vehicle similar to a known drive recorder. On the other hand, when the control unit 11 determines that the vehicle is not in motion (No in Sp24), it determines whether the vehicle has experienced a load collapse from the acquired vehicle information (such as an in-warehouse camera not shown) (Sp26).

[0042] Next, when the control unit 11 determines that the vehicle has experienced a load collapse (Yes in Sp26), it turns off the first microphone and the second microphone and turns on the third microphone via the microphone control unit 25 (Sp27) and proceeds to the process of Sp28. This is because when the vehicle has experienced a load collapse, from the perspective of safe driving support, it is preferable to preferentially acquire the audio inside the warehouse. On the other hand, when the control unit 11 determines that the vehicle has not experienced a load collapse (No in Sp26), it determines whether the driver (passenger) is working from the acquired vehicle information (Sp28).

[0043] Next, when the control unit 11 determines that the driver is working (Yes in Sp28), it turns on the second microphone and the third microphone and turns off the first microphone via the microphone control unit 25 (Sp29), and proceeds to the process of Sp30. This is because when the driver is working, it is preferable to preferentially acquire the sound outside the vehicle (including inside the warehouse) from the viewpoint of safety support. On the other hand, when it is determined that the driver is working (No in Sp28), it is determined whether there is a G trigger (whether acceleration has been detected) from the acquired vehicle information (Sp30).

[0044] Next, when the control unit 11 determines that there is a G trigger (Yes in Sp30), it turns on the first microphone, the second microphone, and the third microphone via the microphone control unit 25 (Sp31), and proceeds to the process of Sp32. This is because when there is a G trigger, it is preferable to acquire all the sounds inside and outside the vehicle (including inside the warehouse) from the viewpoint of safe driving support. On the other hand, when the control unit 11 determines that there is no G trigger (No in Sp30), it is determined whether there is a change in the vehicle state from the acquired vehicle information (Sp32).

[0045] Next, when the control unit 11 determines that there is a change in the vehicle state (Yes in Sp32), it returns to the process of Sp21. On the other hand, when it is determined that there is no change in the vehicle state (No in Sp32), the operation is temporarily terminated. After the operation is terminated, the control unit 11 starts the operation at a predetermined timing. Note that when the control unit 11 determines that there is no change in the vehicle state (No in Sp32), it may return to the process of Sp32 at a predetermined timing.

[0046] As described above regarding the operation of the operation management system 1, in this example, the determination conditions in the processes of Sp24, Sp26, and Sp28 correspond to the "predetermined priority conditions" (see also FIG. 4). Also, in this example, the determination condition in the process of Sp22 corresponds to the "voice unnecessary condition" (see also FIG. 4). Also, in this example, the determination condition in the process of Sp30 corresponds to the "voice necessary condition" (see FIG. 4).

[0047] As described above, according to the present embodiment, when a predetermined priority condition is satisfied, the control unit 11 generates a control signal for adjusting the detection sensitivity of at least one of the plurality of microphones 26 to be higher than the detection sensitivity of the other microphones 26. Thereby, in the present embodiment, the risk that necessary voice becomes difficult to hear or clear voice can be obtained only from one selected microphone as in the prior art is eliminated. That is, according to the present embodiment, clear voice can be obtained from one or more microphones 26 selected according to the situation among the plurality of microphones 26.

[0048] Furthermore, according to the present embodiment, without mounting a plurality of microphone processing units 24, only one microphone processing unit 24 can obtain clear voice from one or more microphones 26 selected according to the situation among the plurality of microphones 26, so that the cost can be reduced compared with the case of mounting a plurality of microphone processing units 24.

[0049] Furthermore, according to the present embodiment, since the plurality of microphones 26 include an in-vehicle microphone and an out-of-vehicle microphone, the in-vehicle and out-of-vehicle voices can be selectively acquired according to the situation of the vehicle (that is, when a predetermined priority condition is satisfied).

[0050] Furthermore, according to the present embodiment, since the plurality of microphones 26 include an in-compartment microphone mounted on the cargo bed of the vehicle as an out-of-vehicle microphone, the voice in the cargo bed (in the compartment) can be selectively acquired according to the situation of the vehicle (that is, when a predetermined priority condition is satisfied).

[0051] Furthermore, according to the present embodiment, when the priority condition is not satisfied and the voice unnecessary condition is satisfied, by turning off the plurality of microphones 26, unnecessary voice can be prevented from being acquired according to the situation.

[0052] Furthermore, according to the present embodiment, even when the priority condition is satisfied, when the voice necessary condition is satisfied, the plurality of microphones 26 are turned on and have substantially equal detection sensitivities, or the detection sensitivities of the plurality of microphones 26 are maximized. Thereby, according to the present embodiment, even in a situation where the priority condition is satisfied, voice can be acquired from the plurality of microphones 26 in a situation where the voice necessary condition that should be prioritized over it is satisfied.

[0053] <Other embodiments> Note that the present invention is not limited to the above-described embodiments, and can be appropriately modified, improved, etc. In addition, the material, shape, dimensions, number, arrangement location, etc. of each component in the above-described embodiments are arbitrary as long as the present invention can be achieved, and are not limited.

[0054] Here, the features of the embodiments of the operation management system according to the present invention described above are briefly summarized and listed in the following [1] to [5] respectively.

[0055] [1] A plurality of microphones (26) mounted on a vehicle and inputting detected voice, A microphone processing unit (24) that receives inputs from the plurality of microphones (26), A control unit (11) that generates a control signal for adjusting the detection sensitivity of at least one of the plurality of microphones (26) to be higher than the detection sensitivity of the other microphones (26) when a predetermined priority condition is satisfied, A microphone control unit (25) that is respectively connected to the plurality of microphones (26) and adjusts the detection sensitivities of the plurality of microphones (26) based on the control signal, An operation management system (1).

[0056] According to the configuration of [1] above, when a predetermined priority condition is satisfied, the control unit generates a control signal for adjusting the detection sensitivity of at least one of the plurality of microphones to be higher than that of the other microphones. As a result, the above configuration eliminates the possibility that necessary voices are difficult to hear as in the prior art, or that clear voices can be obtained only from one selected microphone. That is, according to the above configuration, clear voices can be obtained from one or more microphones selected according to the situation among the plurality of microphones.

[0057] [2] The operation management system (1) described in [1] above, The plurality of microphones (26) are An in-vehicle microphone mounted inside the vehicle on which the driver of the vehicle rides, And an out-vehicle microphone mounted outside the vehicle, Operation management system (1).

[0058] According to the configuration of [2] above, since the plurality of microphones include an in-vehicle microphone and an out-vehicle microphone, it is possible to selectively acquire voices inside and outside the vehicle according to the situation of the vehicle (that is, when a predetermined priority condition is satisfied).

[0059] [3] The operation management system (1) described in [1] or [2] above, The plurality of microphones (26) are As the out-vehicle microphone, it has an in-compartment microphone mounted on the loading platform of the vehicle, Operation management system (1).

[0060] According to the configuration of [3] above, since the plurality of microphones include an in-compartment microphone mounted on the loading platform of the vehicle as the out-vehicle microphone, it is possible to selectively acquire voices of the loading platform (inside the compartment) according to the situation of the vehicle (that is, when a predetermined priority condition is satisfied).

[0061] [4] The operation management system (1) according to any one of the above [1] to the above [3], When the priority condition is not satisfied and the voice unnecessary condition is satisfied, turning off the plurality of microphones (26). Operation management system (1).

[0062] According to the configuration of the above [4], when the priority condition is not satisfied and the voice unnecessary condition is satisfied, by turning off the plurality of microphones, unnecessary voice can be prevented from being acquired according to the situation.

[0063] [5] The operation management system (1) according to any one of the above [1] to the above [4], Even when the priority condition is satisfied, when the voice necessary condition is satisfied, turning on the plurality of microphones and setting the detection sensitivities thereof to be substantially equal, or maximizing the detection sensitivity of the plurality of microphones (26). Operation management system (1).

[0064] According to the configuration of the above [5], even when the priority condition is satisfied, when the voice necessary condition is satisfied, turning on the plurality of microphones and setting the detection sensitivities thereof to be substantially equal, or maximizing the detection sensitivity of the plurality of microphones. Thus, according to the above configuration, even in a situation where the priority condition is satisfied, voice can be acquired from the plurality of microphones in a situation where the voice necessary condition, which should be given priority over the former, is satisfied.

Description of Reference Numerals

[0065] 1 Operation management system 10 Vehicle-mounted device 11 Control unit 12 Sensor I / F 13 SW input unit 14 Card I / F 15 Volatile memory 16 Non-volatile memory 17 External input I / F 18 Communication unit 19 Speed I / F 20 Engine I / F 21 GPS Receiver Unit 22 Analog I / F 23 External Output I / F 24 Microphone Processing Unit 25 Microphone Control Unit 26 Microphone

Claims

1. A plurality of microphones mounted on the vehicle for inputting detected voices; a microphone processor for receiving input from the plurality of microphones; a control unit that generates a control signal for adjusting the detection sensitivity of at least one of the plurality of microphones so that the detection sensitivity of the at least one microphone is higher than the detection sensitivity of the other microphones when a predetermined priority condition is satisfied; a microphone control unit connected to each of the plurality of microphones and configured to adjust the detection sensitivity of the plurality of microphones based on the control signal; Traffic management system.

2. The traffic management system according to claim 1, The plurality of microphones include An in-vehicle microphone mounted inside the vehicle in which the driver of the vehicle sits; An exterior microphone mounted on the exterior of the vehicle. Traffic management system.

3. The traffic management system according to claim 2, The plurality of microphones include The vehicle exterior microphone includes an interior microphone mounted on a loading platform of the vehicle. Traffic management system.

4. The traffic management system according to claim 1, When the priority condition is not satisfied and a voice unnecessary condition is satisfied, the plurality of microphones are turned off. Traffic management system.

5. The traffic management system according to claim 1, Even if the priority condition is satisfied, when a voice necessary condition is satisfied, the plurality of microphones are turned on and have substantially equal detection sensitivity, or the detection sensitivity of the plurality of microphones is maximized. Traffic management system.

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