JP2022011195A - Vehicle approach notification sound control apparatus - Google Patents

Abstract

To issue a notification sound effectively enabling a pedestrian and the like to pay attention to.SOLUTION: In a notification sound control apparatus 30, detecting a pedestrian by a camera 12 and an obstacle detection sensor 14, a notification sound control circuit 32 sets a notification sound with frequencies continuously changed with a given frequency range and issues the set notification sound. This technique, using the notification sound changing its timber characteristically, effectively enables a pedestrian, to which the vehicle itself approaches, to pay attention.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vehicle approach notification sound control device that controls a notification sound.

In a vehicle equipped with an electric motor as a driving source for traveling, a vehicle approach notification device (AVAS: Acoustic Vehicle Alerting System) for notifying pedestrians of the approach of the own vehicle is installed. For this reason, various proposals have been made for vehicle warning sounds.

For example, the approach notification sound control device of Patent Document 1 includes cameras directed to the front, rear, left, and right of the vehicle, as well as left and right, rear, left front doors, and front right of the front of the vehicle. It is equipped with a semi-directional speaker provided in each of the unit doors and a super-directional speaker in which a designated direction is movable.

In the approach notification sound control device of Patent Document 1, the control circuit searches for the position and number of pedestrians from each camera image, and adjusts the speaker that emits the approach notification sound according to the searched position of the pedestrian. Further, in the approach notification sound control device, when there is only one pedestrian, the super directional speaker is turned on and the direction of the super directional speaker is adjusted so as to track the pedestrian.

Japanese Unexamined Patent Publication No. 2019-167023

By the way, pedestrians can recognize that the vehicle is traveling in the vicinity by the notification sound, but the mere notification sound does not call attention to pedestrians around the vehicle. difficult. For this reason, there is room for improvement in alerting pedestrians and the like with respect to the notification sound emitted by the vehicle.

The present invention has been made in view of the above facts, and an object of the present invention is to provide a vehicle approach notification sound control device capable of effectively alerting an object such as a pedestrian in a vehicle approach notification device.

The vehicle approach notification sound control device according to claim 1 of the present invention has a detection means for detecting an object around the own vehicle, and when the object is detected, the approach of the own vehicle is detected by the own vehicle. It includes a control means for continuously changing the frequency of the notification sound for notifying the surroundings in a predetermined frequency range.

The vehicle approach notification sound control device according to claim 1 notifies the approach of the own vehicle to the surroundings of the own vehicle by sounding a notification sound around the own vehicle while the vehicle is running. Here, the detecting means detects an object around the own vehicle, and the control means continuously changes the frequency of the notification sound in a predetermined frequency range when the object is detected.

As a result, the tone color of the notification sound can be characteristically changed, and pedestrians and the like around the own vehicle can be effectively alerted to the own vehicle. Moreover, it is possible to effectively alert the occupants of the own vehicle.

The vehicle approach notification sound control device according to claim 2 is the notification in claim 1, so that the control means can be heard as different sounds depending on whether the vehicle is moving forward or backward. Control the sound.

In the vehicle approach notification sound control device of claim 2, the control means controls the notification sound so that it can be heard as a different sound depending on whether the vehicle is moving forward or backward. As a result, the notification sound emitted around the own vehicle is heard as a different sound depending on whether the own vehicle is moving forward or backward, so that pedestrians around the own vehicle, etc. Can recognize whether the vehicle is moving forward or backward, and can alert pedestrians about the direction of travel of the own vehicle.

According to the vehicle approach notification sound control device of claim 1, since the tone color of the notification sound changes characteristically, the effect that pedestrians and the like around the own vehicle can be effectively alerted to the own vehicle can be obtained. Have.

According to the vehicle approach notification sound control device of claim 2, since the notification sound emitted around the own vehicle is heard as a different sound between the forward movement and the reverse movement of the own vehicle, the pedestrian with respect to the own vehicle in which the notification sound moves forward and backward. It has the effect of calling attention to such things.

It is a block diagram which shows the schematic structure of the main part of the vehicle approach notification device equipped with the notification sound control device which concerns on this embodiment. It is a schematic diagram which shows the hardware composition of the main part of the controller of a vehicle approach notification device. It is a functional block diagram which shows the notification sound control circuit formed in a controller. It is a flow chart which shows the outline of the notification sound control processing which concerns on this embodiment. It is a chart which shows the pattern of the notification sound which concerns on this embodiment.

Hereinafter, an example of the embodiment of the present invention will be described with reference to the drawings. In each drawing, the same or equivalent components and parts are given the same reference numerals.

In the present embodiment, the vehicle is mounted on a vehicle (not shown) such as an EV (Electric Vehicle) or HEV (Hybrid Electric Vehicle) equipped with an electric motor (electric motor) as a driving source for traveling, and the approach of the vehicle is notified to the surroundings. The vehicle approach notification device (AVAS) 10 of the above will be described as an example. FIG. 1 shows a schematic configuration of a main part of the vehicle warning sounds device 10 in a block diagram.

As shown in FIG. 1, a vehicle equipped with a vehicle warning device 10 is equipped with a plurality of cameras 12 as an object detection means and an image pickup means, and an obstacle detection sensor 14 as an object detection means. .. Further, the vehicle is equipped with a vehicle speed sensor 16 as a vehicle speed detecting means for detecting the vehicle speed and a wheel speed sensor 18 as a forward / backward movement detecting sensor for detecting the forward / backward movement of the vehicle.

Further, the vehicle approach notification device 10 includes a controller 20 that controls the operation of the device, and the controller 20 constitutes an approach notification control circuit. A plurality of cameras 12, an obstacle detection sensor 14, a vehicle speed sensor 16, and a wheel speed sensor 18 are electrically connected to the controller 20.

The camera 12 includes, for example, a front camera that captures the front of the vehicle, a left camera that captures the left side of the vehicle, a right camera that captures the right side of the vehicle, a rear camera that captures the rear of the vehicle, and the like (all not shown). Is included. The camera 12 is not limited to this, and the camera 12 may have a configuration capable of capturing an image of the surroundings of the vehicle over the entire circumference of the vehicle.

For example, a millimeter-wave radar or the like is used for the obstacle detection sensor 14, and the obstacle detection sensor 14 is ejected from the vehicle in all directions and is a person (pedestrian) or an obstacle as an object around the vehicle. By receiving the millimeter wave reflected by the object, the object around the own vehicle is detected. Further, the obstacle detection sensor 14 can specify the direction and distance of the detected object. The obstacle detection sensor 14 is not limited to the millimeter wave radar, and may be configured to be capable of acquiring the direction and distance of obstacles around the vehicle.

The controller 20 of the vehicle approach notification device 10 extracts an object such as a pedestrian or an obstacle around the vehicle from the image taken by the camera 12, and determines the direction and distance of the extracted object with respect to the vehicle by the obstacle detection sensor 14. Identify.

The vehicle speed sensor 16 detects the vehicle speed and outputs a signal corresponding to the detected vehicle speed. The vehicle speed sensor 16 is provided on, for example, an axle on which the vehicle travels at a speed (vehicle speed) corresponding to the rotation speed by being rotated, a wheel rotated by the rotation of the axle, and a pulse signal corresponding to the rotation speed. Is output. The controller 20 detects the vehicle speed by counting the pulse signal output from the vehicle speed sensor 16.

The wheel speed sensor 18 is attached to a wheel (not shown) that rotates when the vehicle travels, and outputs a signal according to the rotation direction of the wheel. The controller 20 detects whether the vehicle is traveling forward or backward from the output signal of the wheel speed sensor 18. Further, the wheel speed sensor 18 may output a signal according to the vehicle speed, whereby the controller 20 can detect the vehicle speed from the output signal of the wheel speed sensor 18.

In the vehicle approach notification device 10 according to the present embodiment, the camera 12, the obstacle detection sensor 14, the vehicle speed sensor 16, and the wheel speed sensor 18 are used to cover objects such as pedestrians, dogs, and other animals around the vehicle, and the vehicle. It is possible to detect driving information including the distance between the vehicle and the object and the forward / backward movement of the own vehicle.

In the present embodiment, the vehicle speed sensor 16 and the wheel speed sensor 18 are provided, but the wheel speed sensor 18 may be omitted if the vehicle speed sensor 16 can detect the traveling direction (forward or reverse) of the vehicle. If the vehicle speed can be detected by the wheel speed sensor 18, the vehicle speed sensor 16 may be omitted. Further, when the vehicle is equipped with an automatic driving system that enables driving control of the vehicle without the driver's driving operation, the output signals of the camera 12, the obstacle detection sensor 14, the vehicle speed sensor 16 and the wheel speed sensor 18 are installed. Instead of, the output signal of the automatic driving system may be used.

On the other hand, the vehicle warning device 10 includes a plurality of speakers (SP: Speaker) 24 as sounding means, and each of the speakers 24 is electrically connected to the controller 20. The speakers 24 include, for example, a speaker 24FL arranged on the left side in the vehicle width direction in the front part of the vehicle, a speaker 24FR arranged on the right side in the vehicle width direction in the front part of the vehicle, and a speaker 24RL arranged on the left side in the vehicle width direction in the rear part of the vehicle. , And the speaker 24RR arranged on the left side in the vehicle width direction at the rear of the vehicle is included. As a result, the vehicle approach notification device 10 is capable of producing a notification sound from each of the front portion and the rear portion of the vehicle toward the periphery of the vehicle.

Further, the controller 20 is formed with amplifiers (Amp: Amplifier) 22F and 22R for amplifying an electric signal (waveform signal) for producing a notification sound. The speakers 24FL and 24FR at the front of the vehicle are electrically connected to the amplifier 22F, and the speakers 24RL and 24RR at the rear of the vehicle are electrically connected to the amplifier 22R.

In the controller 20, when the vehicle speed of the vehicle detected by the vehicle speed sensor 16 is within the preset speed range, a waveform signal for obtaining a predetermined notification sound is generated and input to the amplifiers 22F and 22R. When the waveform signal of the notification sound is input to the amplifiers 22F and 22R, the input waveform signal is amplified at an amplification factor corresponding to a preset sound pressure, and each of the speakers 24FL, 24FR, 24RL, and 24RR is amplified. Drive.

As a result, in the vehicle approach notification device 10, the notification sound corresponding to the waveform signal generated while the vehicle is traveling in the predetermined speed range is set to a predetermined sound pressure from the speakers 24FL, 24FR, 24RL, and 24RR, and the notification sound is output. To. The vehicle approach notification device 10 emits a notification sound satisfying the specified conditions.

On the other hand, the vehicle approach notification device 10 is provided with a notification sound control device 30 as a vehicle approach notification sound control device according to the present embodiment, and the notification sound control device 30 is provided from the speaker 24 in the vehicle approach notification device 10. Controls the frequency and pressure of the sound sounds. The notification sound control device 30 includes a notification sound control circuit 32 and a sound source 34 as control means, and the notification sound control circuit 32 and the sound source 34 are formed in the controller 20 of the vehicle approach notification device 10. FIG. 2A shows an example of a hardware configuration for forming the notification sound control circuit 32 in the controller 20 in a block diagram, and FIG. 2B shows a main part of the notification sound control circuit 32 in a functional block diagram. It is shown.

As shown in FIG. 2A, the controller 20 includes a CPU (Central Processing Unit) 36A, a ROM (Read Only Memory) 36B, a RAM (Random Access Memory) 36C, a storage 36D, and an input / output interface 36E via a bus 36F. Microcomputers that are connected to each other so that they can communicate (send and receive data) are formed.

The CPU 36A is a central arithmetic processing unit that executes various programs and controls each unit. The ROM 36B stores various programs and various data. The RAM 36C temporarily stores a program or data as a work area. The storage 36D is composed of an HDD (Hard Disk Drive) or an SSD (Solid State Drive), and stores various programs including an operating system and various data. The input / output interface 36E is an interface for exchanging data in the controller 20 and with various devices connected to the controller 20.

In the controller 20, the CPU 36A reads the program from the ROM 36B or the storage 36D, and executes the program using the RAM 36C as a work area. In the controller 20, various functions are realized by the CPU 36A performing arithmetic processing according to the program recorded in the ROM 36B or the storage 36D.

In the present embodiment, the ROM 36B or the storage 36D stores a notification sound processing program for controlling the notification sound. As a result, as shown in FIG. 2B, in the notification sound control circuit 32 of the controller 20, the functions of the travel information determination unit 40 and the notification sound setting unit 42 for determining various information (driving information) related to vehicle travel. Is realized. Further, in the notification sound control device 30, the sound source 34 is realized by, for example, the storage 36D.

The driving information determination unit 40 inputs captured images output from the camera 12, an output signal of the obstacle detection sensor 14, an output signal of the vehicle speed sensor 16, an output signal of the wheel speed sensor 18, and the like as driving information of the vehicle. Will be done.

The traveling information determination unit 40 determines the traveling speed (vehicle speed) of the vehicle from the output signal of the vehicle speed sensor 16, and determines whether the vehicle is moving forward or backward, that is, traveling forward or backward from the output signal of the wheel speed sensor 18. Further, the traveling information determination unit 40 extracts a pedestrian or the like as an object around the own vehicle from the image taken by the camera 12, and determines the direction and distance of the extracted object by the obstacle detection sensor 14.

The sound source 34 stores a plurality of sound source data (waveform data) set to be output as a notification sound. For example, data showing each sine and cosine waveform of a plurality of frequencies can be applied to the waveform data as the sound source data stored in the sound source 34.

When the vehicle speed of the vehicle is within the speed range set to emit the notification sound, the notification sound setting unit 42 reads the sound source data (waveform data) from the sound source 34 and outputs the notification sound (waveform signal of the notification sound). Set. The notification sound may be the same for the speakers 24FL and 24FR at the front of the vehicle and the speakers 24RL and 24RR at the rear of the vehicle, but at least a part of the waveform signal, the sound pressure, and the phase of the notification sound setting unit 42. Either (output timing) is different.

The notification sound setting unit 42 outputs the waveform signal of the set notification sound to each of the amplifiers 22F and 22R. As a result, the controller 20 sounds the notification sound set in the notification sound setting unit 42 from each of the speakers 24FL and 24FR, and the speakers 24RL and 24RR.

In the notification sound setting unit 42, a standard notification sound having a frequency (frequency fs) and a sound pressure preset as a notification sound is set. Further, in the notification sound setting unit 42, it is possible to set a notification sound having at least one different frequency, sound pressure, and phase between the speakers 24FL and 24FR at the front of the vehicle and the speakers 24RL and 24RR at the rear of the vehicle. ..

These notification sounds may be single sounds or sounds (synthetic sounds) in which waveform data of a plurality of frequencies (waveform data of a sine wave) are superimposed at a level set for each frequency. That is, the notification sound has one or a plurality of frequency spectra, and the notification sound setting unit 42 can set a plurality of notification sounds having different at least a part of the frequency spectrum.

The notification sound setting unit 42 sets so that when the vehicle speed is in the preset speed range, the standard notification sound of the preset frequency fs and sound pressure is sounded. Further, the notification sound setting unit 42 sets a notification sound having a frequency different from that of the standard notification sound according to the travel information of the vehicle determined by the travel information determination unit 40.

In the present embodiment, the setting of the notification sound having a frequency different from the frequency of the standard notification sound is a determination that an object such as a pedestrian around the vehicle (hereinafter, pedestrian is taken as an example) is detected from the traveling information. It is supposed to be done. In the present embodiment, the case where it is determined that a pedestrian around the vehicle is detected means that the distance between the vehicle and the pedestrian is within a predetermined range as an example, and the distance within the predetermined range is defined as the distance within the predetermined range. The distance is set so that it is judged that pedestrians do not affect the running of the vehicle.

Further, in the notification sound setting unit 42, the notification sound having a frequency different from that of the standard notification sound is a notification sound in which the frequency is continuously changed within a predetermined frequency range. This frequency range is a range from the frequency f1 to the frequency f2, the frequency f2 is a frequency higher than the frequency fs of the standard notification sound (fs <f2), and the frequency f1 is a frequency equal to or lower than the frequency fs of the standard notification sound. (F1 ≦ fs) (f1 ≦ f ≦ f2).

As a result, the notification sound setting unit 42 can set a notification sound in which the frequency f is continuously changed in one direction (frequency sweep) in the range of the frequency f1 to the frequency f2 within a predetermined cycle (time t). The notification sound of the frequency f may be a single sound or a sound having a plurality of frequency spectra.

Further, the notification sound setting unit 42 applies the forward / backward movement of the vehicle as traveling information, and the speakers 24FL and 24FR on the front side of the vehicle and the rear of the vehicle are used depending on whether the vehicle is moving forward or backward. It is set so that at least one of the sound pressure, the phase, and the time t, which is the cycle of the sweep, is different between the side speakers 24RL and 24RR. That is, the notification sound setting unit 42 can be set so that the notification sound emitted by the speakers 24FL and 24FR at the front of the vehicle and the speakers 24RL and 24RR at the rear of the vehicle can be heard as different notification sounds.

Next, as the operation of the present embodiment, the presence / absence of pedestrians around the vehicle and the traveling direction (forward / backward) of the vehicle are applied as the traveling information of the vehicle, and the notification sound control process according to the traveling information will be described. .. FIG. 3 shows an example of the notification sound control process according to the present embodiment in a flow chart, and FIG. 4 shows an example of the pronunciation pattern of the notification sound applied to the present embodiment in a chart.

The flowchart shown in FIG. 3 is repeatedly executed while the vehicle is running (a period from the start of running to the end of running), and the notification sound control circuit 32 determines the vehicle speed in the first step 100. In this vehicle speed determination, it is determined whether or not the vehicle speed V (km / h) of the vehicle detected by the vehicle speed sensor 16 is within a predetermined speed range (0 ≦ V ≦ Vh) set to emit a notification sound. ..

When the vehicle is traveling at high speed (V> Vh), for example, the notification sound control circuit 32 makes a negative determination in step 100 (step 100: N), proceeds to step 102, and stops the sounding of the notification sound. Set to. As a result, in the controller 20, the output of the waveform signal of the notification sound to the amplifiers 22F and 22R is stopped, and the sound of the notification sound from each of the speakers 24FL, 24FR, 24RL and 24RR is stopped. In the notification sound control circuit 32, when the vehicle is stopped (V = 0 km / h), a negative determination may be made in step 100.

On the other hand, in the notification sound control circuit 32, if the vehicle speed V of the vehicle is within the predetermined speed range (0 ≦ V ≦ Vh), a positive determination is made in step 100 (step 100: Y), and the process proceeds to step 104. In step 104, the notification sound control circuit 32 applies a frequency fs and a sound pressure notification sound (standard notification sound) having a preset pitch (tone) as the notification sound, and sets the standard notification sound to be sounded. do.

As a result, in the controller 20, the waveform signal of the standard notification sound is amplified by each of the amplifiers 22F and 22R, and each of the speakers 24FL, 24FR, 24RL, and 24RR is driven to produce the standard notification sound and the vehicle. Notify the approach of the vehicle to the surrounding area.

Here, the notification sound control circuit 32 confirms whether or not a pedestrian as an object is detected in step 106. The notification sound control circuit 32 detects a pedestrian by extracting a pedestrian from the captured image of the camera 12, and the obstacle detection sensor 14 identifies the direction and distance of the detected pedestrian with respect to the own vehicle.

As a result, when the notification sound control circuit 32 detects a pedestrian within a preset distance with respect to the own vehicle, it makes an affirmative determination (step 106: Y) in step 106 and proceeds to step 108. In step 108, the notification sound control circuit 32 determines the traveling direction of the vehicle for confirming whether or not the vehicle is moving forward.

At this time, if the vehicle is traveling forward, the notification sound control circuit 32 makes an affirmative determination in step 108 (step 108: Y), and proceeds to step 110. In this step 110, the notification sound control circuit 32 sets the frequency f as the first pattern as a change pattern of the notification sound that is sounded while being swept in the range of the frequency f1 to the frequency f2.

On the other hand, when the vehicle is traveling in reverse, the notification sound control circuit 32 makes a negative determination in step 108 (step 108: N), and proceeds to step 112. In this step 112, the notification sound control circuit 32 is a change pattern of the notification sound that is sounded while sweeping the frequency f in the range of the frequency f1 to the frequency f2, and is set to a second pattern different from the first pattern.

As a result, the controller 20 is notified of the approach of the own vehicle to the surroundings of the own vehicle by the notification sound emitted from each of the speakers 24FL, 24FR, 24RL, and 24RR in the set change pattern.

In the next step 114, the notification sound control circuit 32 determines whether or not the object (pedestrian) is not detected. When the vehicle is separated from the pedestrian by a predetermined distance or more, the notification sound control circuit 32 makes an affirmative determination in step 114 (step 114: Y), and proceeds to step 116. In step 116, the notification sound control circuit 32 returns the notification sound set so that the frequency f is swept back to the standard notification sound.

As a result, the controller 20 makes the standard notification sound sound from each of the speakers 24FL, 24FR, 24RL, and 24RR. If the pedestrian continues to be detected, the notification sound control circuit 32 makes a negative determination in step 114 (step 114: N), proceeds to step 108, and is set to sweep the frequency f. Set the sound to continue sounding.

On the other hand, in the notification sound control circuit 32, the speed determination for determining whether or not the vehicle speed V is out of the predetermined speed range is performed in step 118. Here, if the vehicle speed V exceeds the predetermined speed range and deviates from the predetermined range (V> Vh), an affirmative determination is made in step 118 (step 118: Y), and the process proceeds to step 102. As a result, the controller 20 stops the sounding of the notification sound. If a pedestrian is not detected in step 106, the notification sound control circuit 32 makes a negative determination in step 106 (step 106: N), and proceeds to step 118.

Here, the notification sound control circuit 32 is set to repeatedly sweep the frequency f of the notification sound in the range of the frequency f1 to the frequency f2 within the range of the time t in which the pedestrian is detected.

As shown in FIG. 4, in the notification sound control device 30, when the notification sound is set according to the traveling information, the first pattern and the first pattern are the change patterns of the notification sound emitted from the speakers 24FL, 24FR, 24RL, and 24LL. Two patterns are set. The first pattern is applied when the vehicle moves forward (forward travel), and the second pattern is applied when the vehicle moves backward (reverse travel).

In the first pattern, the notification sound emitted from the speakers 24FL and 24FR and the speakers 24RL and 24RR so that the notification sound (sound source of the notification sound) can be felt as moving from the front side of the vehicle to the rear side of the vehicle. The sound pressure and phase of. Further, in the second pattern, the speakers 24FL and 24FR and the speakers 24RL and 24RR are pronounced so that the notification sound is felt to be moving from the rear side of the vehicle to the front side of the vehicle, contrary to the first pattern. It is the sound pressure and phase of the notification sound.

In order to make the notification sound (sound source of the notification sound) feel as if it is moving in the front-rear direction of the vehicle, for example, one of the speaker 24 (24FL, 24FR) on the front side of the vehicle and the speaker 24 (24RL, 24RR) on the rear side of the vehicle. The sound pressure of the notification sound emitted from the speaker is lower than that of the other, and the phase of the notification sound of one is delayed from that of the other (for example, delayed by the length of the vehicle). In this state, a method such as advancing the phase while increasing the sound pressure of the notification sound emitted from one side and delaying the phase while decreasing the sound pressure of the notification sound emitted from the other side can be applied. At this time, by synchronizing (repeating at time t) the change in sound pressure and phase of the notification sound with the time t (time t1 or time t2) of the frequency sweep, the sound source of the notification sound moves more effectively. I feel like I'm there.

Further, in the notification sound control device 30, the time t for sweeping the notification sound is set to time t1 in the first pattern and time t2 in the second pattern, and the time t1 is shortened by the time t2 (t1 <t2). ..

Therefore, in the vehicle approach notification device 10 provided with the notification sound control device 30, when a pedestrian is detected while the vehicle is traveling forward, the frequency f is relatively short around the vehicle (compared to the time t2). The sound of the notification sound swept from the frequency f1 to the frequency f2 is repeated at the time t1.

As a result, pedestrians around the vehicle are alerted to the vehicle producing the notification sound by the characteristic notification sound whose timbre changes continuously and repeatedly at intervals of time t1. Moreover, this characteristic notification sound can effectively alert occupants such as the driver of the own vehicle to pedestrians and the like around the own vehicle, so that the notification sound can contribute to the safety of the vehicle and pedestrians. ..

Further, in the vehicle approach notification device 10, the sound pressure of the notification sound emitted from the speakers 24FL and 24FR on the front side of the vehicle so that the notification sound is felt to be moving from the front side of the vehicle to the rear side of the vehicle in the vehicle traveling forward. And the phase, and the sound pressure and phase of the notification sound emitted from the speakers 24FL and 24FR on the rear side of the vehicle are controlled. As a result, pedestrians around the vehicle hear the notification sound heard from the front side of the vehicle and the notification sound heard from the rear side of the vehicle as different sounds (tones, etc.). Therefore, the attention is alerted by the notification sound whose tone color, sound pressure, and phase are controlled, and it is possible to recognize whether or not the vehicle traveling forward is approaching itself, which can further contribute to the safety of pedestrians.

Further, in the vehicle approach notification device 10 provided with the notification sound control device 30, when a pedestrian is detected while the vehicle is moving backward, the frequency f is relatively long around the vehicle (longer than the time t1). ) At time t2, the sound of the notification sound swept from the frequency f1 to the frequency f2 is repeated. As a result, pedestrians around the vehicle are alerted to the vehicle because the tone of the notification sound changes at intervals of time t2.

Further, in the vehicle approach notification device 10, the sound pressure of the notification sound emitted from the speakers 24FL and 24FR on the front side of the vehicle so that the notification sound is felt to be moving from the rear side of the vehicle to the front side of the vehicle in the vehicle traveling backward. And the phase, and the sound pressure and phase of the notification sound emitted from the speakers 24FL and 24FR on the rear side of the vehicle are controlled. As a result, pedestrians around the vehicle can recognize whether or not the vehicle traveling in reverse is approaching itself by the notification sound whose sound pressure and phase are controlled together with the tone color, so that the sound is emitted from the vehicle. It is effectively alerted by the notification sound.

In this way, when the notification sound control circuit 32 detects a pedestrian or the like around the own vehicle, the notification sound control circuit 32 repeatedly produces a notification sound in which the frequency f of the notification sound is continuously changed in the range of the frequency f1 to the frequency f2. Control to be done. As a result, the pedestrian is alerted by the notification sound whose tone color is repeatedly changed, and can accurately recognize the approach of the vehicle.

Further, since the timbre change interval of the notification sound differs depending on whether the vehicle is moving forward or backward, a pedestrian or the like can easily distinguish whether the approach of the vehicle is forward or backward. Further, since the notification sound is emitted so that the sound source feels that the sound source is moving in the front-rear direction of the vehicle, the pedestrian can easily recognize the traveling direction of the vehicle. Moreover, pedestrians can recognize whether the vehicle is approaching or moving away.

In the present embodiment described above, the frequency of the notification sound is changed in one direction from a low frequency to a high frequency, but the change direction of the frequency of the notification sound is different between when the vehicle is moving forward and when the vehicle is moving backward. You may. For example, the change in the frequency of the notification sound may be continuously changed from a high frequency to a low frequency when the vehicle is moving backward, which makes it possible for a pedestrian to more clearly distinguish between the time when the vehicle is moving forward and the time when the vehicle is moving backward. can.

Further, the notification sound may be a sound having a plurality of frequency spectra. In this case, it is sufficient that the frequencies corresponding to the respective frequency spectra are continuously changed so that the plurality of frequency spectra maintain the ratio between each other.

Further, in the present embodiment, it has been described that the notification sound whose frequency is changed so as to be continuous in a predetermined frequency range is set. However, the notification sound is not limited to this, and may be a notification sound to which a characteristic frequency change is applied, such as a notification sound that changes so that a high frequency and a low frequency are alternately switched.

Further, in the present embodiment described above, the sound source data is stored in the sound source 34. However, the sound source may be subject to the function of a so-called synthesizer that generates waveform data of a plurality of frequencies and synthesizes the generated waveform data to generate sound source data. In this case, for example, the notification sound setting unit 42 outputs the frequency component of the notification sound and the information indicating the amplitude of each frequency component to the sound source, so that the sound source generates and outputs waveform data according to the input information. You can do it.

Further, the notification sound control process executed by the CPU reading the software (program) in the present embodiment may be executed by various processors other than the CPU. As a processor in this case, in order to execute specific processing such as PLD (Programmable Logic Device) whose circuit configuration can be changed after manufacturing FPGA (Field-Programmable Gate Array) and ASIC (Application Specific Integrated Circuit). An example is a dedicated electric circuit or the like, which is a processor having a circuit configuration designed exclusively for the purpose. Further, the notification sound control process may be executed by one of these various processors, or a combination of two or more processors of the same type or different types (for example, a plurality of FPGAs, and a CPU and an FPGA). It may be executed by combination etc.). Further, the hardware-like structure of these various processors is, more specifically, an electric circuit in which circuit elements such as semiconductor elements are combined.

Further, in each of the above embodiments, the mode in which the notification sound control processing program is stored (installed) in the storage unit (storage 36D or the like) in advance has been described, but the present invention is not limited thereto. The program may be provided in a form recorded on a recording medium such as a CD-ROM (Compact Disk Read Only Memory), a DVD-ROM (Digital Versatile Disk Read Only Memory), and a USB (Universal Serial Bus) memory. Further, the program may be downloaded from an external device via a network.

10 Vehicle warning device 12 Camera (detection means)
14 Obstacle detection sensor (detection means)
16 Vehicle speed sensor 18 Wheel speed sensor 20 Controller 22F, 22R Amplifier 24FL, 24FR Speaker 24RL, 24RR Speaker 30 Notification sound control device (Vehicle approach notification sound control device)
32 Notification sound control circuit (control means)
34 Sound source 40 Driving information judgment unit 42 Notification sound setting unit

Claims (2)

Detection means for detecting objects around the own vehicle,
When the object is detected, a control means for continuously changing the frequency of the notification sound for notifying the approach of the own vehicle to the surroundings of the own vehicle in a predetermined frequency range, and
Vehicle warning sound control device including. The vehicle approach notification sound control according to claim 1, wherein the control means controls the notification sound so that it can be heard as a different sound depending on whether the vehicle is moving forward or backward. Device.

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