Notification device of vehicle, notification method of vehicle and program of the same

Abstract

To reduce the possibility that an occupant may feel troublesome about notification sound.SOLUTION: A notification device of a vehicle obtains limiting speed that is applied to an own vehicle lane, on the basis of image data obtained by a camera device (20), and when own vehicle speed is over the limiting speed, makes a buzzer (42) issue notification sound. The notification device of the vehicle obtains running-environmental sound in a vehicle interior using a microphone (64) in the vehicle interior and then obtains a frequency band and sound pressure of the running-environmental sound. The notification device of the vehicle changes "the frequency band and the sound pressure" of the notification sound issued from the buzzer (42), in accordance with the obtained frequency band and sound pressure of the running-environmental sound.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a vehicle notification device, a notification method, and a program thereof that generate a notification sound for an occupant of a host vehicle.

Background Art

[0002] Conventional devices acquire image data by photographing a scene in front of the host vehicle using an in-vehicle camera, and recognize road signs from the image data. Further, conventional devices generate, as necessary, a notification sound corresponding to the content of the recognized road sign for an occupant of the host vehicle (see Patent Documents 1 to 3).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

[0004] However, conventional devices do not determine the notification sound in consideration of the driving environmental sound (for example, the noise in the vehicle interior accompanying the driving of the host vehicle and the noise generated by the air conditioning device, etc., which is also simply referred to as "the environmental sound in the vehicle interior"). Therefore, regardless of the driving environmental sound, a notification sound with a high sound pressure is always generated so that the occupant of the vehicle can hear the notification sound. As a result, there has been a problem that especially when a situation where the notification sound is generated frequently occurs, the driver may feel bothered by the notification sound. On the other hand, if the sound pressure of the notification sound is low, there is a risk that the driver may not notice the notification sound.

[0005] The present invention has been made to solve such problems. That is, one of the objects of the present invention is to determine the frequency band of a notification sound in consideration of the ambient sound in the vehicle interior, and by generating the notification sound in the determined frequency band, it is possible for passengers including the driver to easily hear it and to generate a notification sound that is less likely to be annoying. It is an object of the present invention to provide a notification device, a notification method, and a program thereof for a vehicle.

[0006] One aspect of the notification device for a vehicle according to the present invention includes a sound generation device (42) mounted on the own vehicle and a controller (10, 40) that controls the sound generation device.

[0007] The controller acquires the ambient sound in the vehicle interior of the own vehicle (S240), determines the frequency band of the notification sound based on the frequency band of the acquired ambient sound (S250, S260), performs a notification operation of notifying the passengers of the own vehicle that the own vehicle is in a predetermined state by generating the notification sound in the determined frequency band from the sound generation device (S270), and is configured as described above.

[0008] According to this aspect, since the frequency band of the generated notification sound is determined based on the frequency band of the ambient sound in the vehicle interior of the own vehicle, the notification sound can be set to a notification sound that is easy for passengers including the driver to hear. As a result, it is not necessary to always increase the sound pressure, so the possibility that the passengers feel annoyed by the notification sound can be reduced.

[0009] In this case, it is preferable to determine the frequency band and sound pressure of the notification sound based on the sound pressure of the ambient sound in addition to the frequency band of the ambient sound (S410, S420). According to this, since the frequency band and sound pressure of the notification sound are determined based on the ambient sound, a more suitable notification sound can be generated.

[0010] In the above description, in order to facilitate the understanding of the present invention, the names and / or symbols used in the embodiments are attached in parentheses to the configurations of the inventions corresponding to the embodiments described later. However, each component of the present invention is not limited to the embodiments defined by the above names and / or symbols. The present invention also extends to a vehicle notification method and its program.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0012] The "vehicle notification device DS (hereinafter referred to as the 'device DS')" according to an embodiment of the present invention includes the components shown in FIG. 1 and is applied (mounted) to the host vehicle HV. The host vehicle HV may be any of a vehicle having an internal combustion engine as a power source, a vehicle having an electric motor as a power source (i.e., an electric vehicle), and a hybrid vehicle.

[0013] In this specification, "ECU" is an electronic control unit (control unit) equipped with a microcomputer including a CPU (processor), ROM, RAM, a writable non-volatile memory for data, and an interface, etc. The ECU is also referred to as a controller or a computer. A plurality of ECUs shown in FIG. 1 are connected to be able to exchange information with each other through a CAN (Controller Area Network). Some or all of these plurality of ECUs may be integrated into one ECU.

[0014] The driving support ECU 10 executes driving support control to generate a notification sound (warning sound) for the driver based on road signs applied to the lane in which the host vehicle HV is traveling (hereinafter referred to as "own lane").

[0015] The camera device 20 includes a camera 21 and an image ECU 22. The camera 21 captures an image of the scene in front of the host vehicle HV every time a predetermined time elapses to acquire image data. The image ECU 22 generates "camera information including the image data itself, camera object information, and lane information" based on the image data from the camera 21 and transmits it to the driving support ECU 10.

[0016] The driving support ECU 10 extracts a "road sign indicating the speed limit (maximum speed)" included in the image data based on the image data acquired by the camera device 20, and recognizes (acquires) the numerical value indicated by the road sign as the "speed limit (maximum speed) set / applied to the own lane". This recognition (acquisition) of the restricted vehicle speed may be performed by the image ECU 22.

[0017] The radar device 30 is a well-known device that acquires information about a target existing in front of the host vehicle HV using radio waves in the millimeter-wave band, and includes a radar 31 and a radar ECU 32. The radar 31 transmits millimeter waves within a predetermined detection range every time a predetermined time elapses, and receives the millimeter waves reflected by the target. The radar 31 transmits information about the transmitted and received millimeter waves to the radar ECU 32. The radar ECU 32 acquires radar information based on the information from the radar 31, and transmits the radar information to the driving support ECU 10. The radar information includes the distance to the target, the azimuth of the target, the relative speed of the target, and the like.

[0018] The notification ECU (warning ECU) 40 is connected to a display 41 disposed at a position visible from the driver's seat and a buzzer 42 which is a sound generating device that generates a notification sound (warning sound), and controls these in response to an instruction (instruction signal) from the driving support ECU 10. The display 41 is provided with a region 41a for displaying the speed limit (maximum speed) and a warning display region 41b for displaying various warning marks. The notification ECU 40 displays the speed limit included in the instruction from the driving support ECU 10 in the region 41a, and displays a warning mark in the warning display region 41b in response to the instruction from the driving support ECU 10. Further, the notification ECU 40 can generate a notification sound (buzzer sound) of "frequency band and sound pressure" included in the instruction from the driving support ECU 10 from the buzzer 42.

[0019] The navigation ECU 50 is connected to a GPS receiver 51, a map database 52 storing map information, and a display touch panel 53 for displaying touch buttons, and together with these, constitutes an in-vehicle navigation system. The navigation ECU 50 acquires the current position of the host vehicle HV based on the GPS signal received by the GPS receiver 51, and based on the acquired current position of the host vehicle HV and the map information stored in the map database 52, can acquire the speed limit set / applied to the current lane at the current time.

[0020] The driving support ECU 10 inputs the detection values or output signals of the following "sensors and microphones". · An accelerator pedal operation amount sensor 61 that detects the accelerator pedal operation amount AP of the host vehicle HV. · A brake pedal operation amount sensor 62 that detects the brake pedal operation amount BP of the host vehicle HV. · A vehicle speed sensor 63 that detects the speed of the host vehicle HV (i.e., the host vehicle speed Vh). · An in-vehicle microphone 64 that converts the in-vehicle environmental sound, which is the sound (noise) inside the vehicle cabin of the host vehicle HV, into an electrical signal.

[0021] The in-vehicle microphone 64 converts the sound near the driver's seat inside the vehicle cabin of the host vehicle HV into an electrical signal and outputs it. Hereinafter, the sound represented by the electrical signal output from the in-vehicle microphone 64 is referred to as "driving environment sound" for convenience.

[0022] (Outline of operation) The device DS acquires the speed limit applied to the host lane based on the image data acquired by the camera device 20.

[0023] On the other hand, the device DS analyzes the driving environment sound acquired through the in-vehicle microphone 64 to acquire at least the frequency band of the driving environment sound. The device DS determines the "frequency band and sound pressure" of a "buzzer sound that is audible (easy for the driver to hear) and not annoying to the driver" based on the frequency band of the driving environment sound.

[0024] When the host vehicle speed Vh exceeds the "acquired speed limit", the device DS generates a buzzer sound having the determined "frequency band and sound pressure" from the buzzer 42.

[0025] (Specific operation) The CPU of the driving support ECU 10 (hereinafter simply referred to as "CPU") executes the routine shown by the flowchart in FIG. 2 every time a predetermined time (operation cycle) dt elapses. In the following, "step" may be denoted as "S".

[0026] When the specified timing arrives, the CPU starts processing from S200 in FIG. 2 and proceeds to S210, and determines whether the speed limit set for the own lane has been newly acquired (recognized from the image) based on the image data transmitted from the camera device 20. Note that the CPU may acquire the speed limit set for the own lane from the current position of the own vehicle HV and the map information via the navigation ECU 50.

[0027] When the speed limit is newly acquired, the CPU proceeds from S210 to S220 and stores the newly acquired speed limit in the RAM as the warning speed limit SPDLMT. At this time, the CPU changes the speed limit displayed in the area 41a of the display 41 to the warning speed limit SPDLMT. Next, the CPU proceeds to S230.

[0028] On the other hand, when the speed limit has not been newly acquired, the process proceeds directly from S210 to S230.

[0029] At S230, the CPU determines whether the vehicle speed Vh detected by the vehicle speed sensor 63 is higher than the warning speed limit SPDLMT. When the vehicle speed Vh is less than or equal to the warning speed limit SPDLMT, the CPU proceeds directly from S230 to S295 and temporarily ends this routine.

[0030] On the other hand, when the vehicle speed Vh is higher than the warning speed limit SPDLMT, the CPU determines "Yes" at S230 and sequentially executes the "processing from S240 to S270" described below. Then, the CPU proceeds to S280.

[0031] Step 240: The CPU acquires the driving environmental sound using the in-vehicle microphone 64. Step 250: The CPU performs waveform analysis of the driving environmental sound including frequency analysis on the acquired driving environmental sound to acquire the frequency band of the driving environmental sound.

[0032] Step 260: Based on the frequency band of the acquired driving environmental sound, the CPU determines the frequency band and sound pressure of the buzzer sound. More specifically, the driving assistance ECU 10 stores the look-up table shown in FIG. 3 in the ROM. In this look-up table, the frequency band of the driving environmental sound is associated with the "frequency band and sound pressure" of a buzzer sound that is "audible (easy for the driver and / or passengers to hear) and not annoying to the driver and / or passengers (hereinafter simply referred to as a 'highly audible buzzer sound')." The CPU determines the "frequency band and sound pressure" of a highly audible buzzer sound for the current driving environmental sound by applying the frequency band of the driving environmental sound acquired in S250 to this look-up table.

[0033] For example, according to the look-up table shown in FIG. 3, when the frequency band f of the acquired driving environmental sound belongs to a low frequency band of 125 (Hz) or less, a buzzer sound having a high frequency band of "1600 (Hz) ± 50 (Hz)" and a sound pressure (sound pressure level) of 57 (dB) is determined as a highly audible buzzer sound.

[0034] S270: The CPU causes the buzzer 42 to generate a buzzer sound having the "frequency band and sound pressure" determined in S260 by sending an instruction to the notification ECU 40.

[0035] At S280, the CPU determines whether or not a certain period of time has elapsed since the time when the buzzer sound started to be generated at S270. If the certain period of time has not elapsed since the time when the buzzer sound started to be generated, the CPU returns to S270.

[0036] When a certain period of time has elapsed since the time when the buzzer sound started to be generated at S270, the CPU determines "Yes" at S280 and proceeds to step 295 to temporarily end this routine. In this way, by performing the processes of S270 and S280, the CPU executes a notification operation to notify the passengers (including the driver) of the host vehicle HV that the host vehicle HV is in a state of traveling exceeding the speed limit SPDLMT (one of the predetermined states).

[0037] As described above, based on the frequency band of the driving environmental sound, the device DS changes the frequency and sound pressure of the buzzer sound generated when the vehicle speed of the host vehicle exceeds the speed limit so that the buzzer sound becomes a "highly audible buzzer sound". Therefore, the driver and passengers can surely hear the notification sound (buzzer sound), so they notice that the host vehicle HV is traveling at a speed exceeding the speed limit and are less likely to feel bothered by the notification sound.

[0038] (Modification example) Next, a modification example of the above embodiment will be described. The CPU according to this modification example differs from the CPU according to the above embodiment only in that it executes the routine shown by the flowchart in FIG. 4 instead of FIG. 2. Hereinafter, this difference will be described. Among the steps shown in FIG. 4, the steps that perform the same processing as the steps shown in FIG. 2 are assigned the reference numerals given to those steps in FIG. 2. A detailed description of such steps will be omitted.

[0039] When the vehicle speed Vh of the host vehicle is higher than the warning speed limit SPDLMT, the CPU proceeds to S240 in FIG. 4 to acquire the driving environmental sound by the processing of "S210 to S230" in FIG. 4.

[0040] Next, the CPU proceeds to S410, performs waveform analysis of the driving environmental sound including frequency analysis on the acquired driving environmental sound, and acquires the frequency band and sound pressure (sound pressure level) of the driving environmental sound.

[0041] Next, the CPU proceeds to S420 and determines the frequency band and sound pressure of the buzzer sound based on the frequency band and sound pressure of the acquired driving environmental sound.

[0042] More specifically, the driving support ECU 10 stores the look-up table shown in FIG. 5 in the ROM. In this look-up table, the "frequency band and sound pressure" of the driving environment sound and the "frequency band and sound pressure" of the buzzer sound with high audibility are stored in an associated manner. The CPU applies the "frequency band and sound pressure" of the driving environment sound acquired in S410 to this look-up table, thereby determining the "frequency band and sound pressure" of the buzzer sound with high audibility for the current driving environment sound.

[0043] For example, according to the look-up table shown in FIG. 5, when the frequency band f of the acquired driving environment sound belongs to the low frequency band of 125 (Hz) or less and the sound pressure P of the acquired driving environment sound is greater than the sound pressure P2, a buzzer sound having a high frequency band of "1600 (Hz) ± 50 (Hz)" and a sound pressure (sound pressure level) of 63 (dB) is determined as the buzzer sound with high audibility. According to the look-up table shown in FIG. 5, when the frequency band f of the driving environment sound belongs to a certain frequency band, the sound pressure of the buzzer sound is determined so that the higher the sound pressure P of the driving environment sound, the greater the sound pressure of the buzzer sound.

[0044] Thereafter, the CPU performs the processes of "S270 and S280" in FIG. 4, and generates a buzzer sound having the "frequency band and sound pressure" determined in S420 at the buzzer 42 for a certain period of time. That is, the CPU executes a notification operation for notifying the occupant (including the driver) of the host vehicle HV that the host vehicle HV is traveling in a state where it exceeds the speed limit (one of the predetermined states).

[0045] As described above, the device DS according to the modified example determines the "frequency and sound pressure of the buzzer sound" based not only on the frequency band of the driving environment sound but also on its sound pressure. Therefore, the driver and the occupant can more surely hear the notification sound (buzzer sound), and it is less likely to feel bothered by the notification sound.

[0046] Note that the present invention is not limited to the above-described embodiments and modified examples, and various modified examples can be adopted within the scope of the present invention.

[0047] For example, the present invention is applicable not only to a notification device that generates a notification sound (buzzer sound) when the vehicle speed Vh exceeds the warning speed limit SPDLMT, but also to a "notification device that notifies that the host vehicle HV is in a predetermined state by generating a buzzer sound" in various driving support controls described below.

[0048] (1) A notification device that recognizes a specific type of road sign based on image data and generates a notification sound when the host vehicle HV does not comply with the traffic rules specified by the road sign. According to this notification device, for example, when a specific type of road sign indicates "stop temporarily" and the host vehicle HV neglects to stop temporarily, the host vehicle HV is in a state of "not complying with the traffic rules specified by the road sign", so a notification sound is generated.

[0049] (2) A notification device including an active cruise control (ACC: following distance control) system that generates a notification sound when the host vehicle HV is in a predetermined state. For example, when the following distance control is canceled, a notification sound is generated by the ACC system. (3) A notification device including a pre-crash safety (PCS: collision avoidance support control) system. For example, when the PCS system notifies the driver of the presence of an obstacle, a notification sound is generated. (4) A notification device including a clearance sonar system that generates a notification sound when the distance between the host vehicle HV and an obstacle becomes less than a threshold distance.

[0050] (5) A notification device including a driver drowsiness and attention warning (DDAW) system. For example, when the driver is determined to be in a drowsy state, a notification sound is generated by the DDAW system. (6) A notification device including a driver monitoring system. For example, when the driver is determined to be driving while distracted, a notification sound is generated by the driver monitoring system. (7) A notification device including a lane departure suppression system (LDA). For example, when there is a risk that the host vehicle HV may deviate from its own lane, a notification sound is generated by the lane departure suppression system. (8) A notification device including a blind spot monitor (BSM) system. For example, when there is another vehicle in the blind spot area of the host vehicle HV or when another vehicle is approaching the blind spot area, a notification sound is generated by the blind spot monitor.

[0051] In the above embodiments and modifications, the driving support ECU 10 has performed waveform analysis including frequency analysis of the driving environment sound. On the other hand, a measuring device that performs "frequency analysis and sound pressure measurement" like a well-known noise measuring device may be provided between the in-vehicle microphone 64 and the driving support ECU 10. In this case, the driving support ECU 10 acquires information about the "frequency band and sound pressure of the driving environment sound" from the measuring device.

[0052] The device DS may cancel the driving environment sound by constantly transmitting a sound wave having a waveform opposite in phase to the sound waveform of the driving environment sound into the vehicle interior. Thereby, the sound pressure of the notification sound (buzzer sound) can be further reduced.

[0053] Furthermore, the present invention is applicable to the host vehicle HV in a state where the driving mode has transitioned from automatic driving to driving by the driver in an autonomous vehicle.

Explanation of Signs

[0054] 10... Driving support ECU (controller), 20... Camera device, 40... Notification ECU, 42... Buzzer (sound generating device), 64... In-vehicle microphone.

Claims

1. In a vehicle notification device including a sound generating device mounted on the vehicle and a controller for controlling the sound generating device, the controller acquires ambient sound in the vehicle interior of the host vehicle, determines the frequency band of a notification sound based on the frequency band of the acquired ambient sound, and executes a notification operation for notifying an occupant of the host vehicle that the host vehicle is in a predetermined state by generating the notification sound in the determined frequency band from the sound generating device. The notification device is configured as described above.

2. The vehicle notification device according to claim 1, wherein the controller determines the frequency band and sound pressure of the notification sound based on not only the frequency band of the ambient sound but also the sound pressure of the ambient sound, and executes the notification operation by generating the notification sound in the determined frequency band and sound pressure from the sound generating device. The notification device is configured as described above.

3. The vehicle notification device according to claim 1 or claim 2, wherein the controller acquires the vehicle speed of the host vehicle, acquires the speed limit applied to the lane in which the host vehicle is traveling, and when the vehicle speed exceeds the speed limit, executes the notification operation to notify that the host vehicle is in a state of traveling in excess of the speed limit as the predetermined state. The vehicle notification device is configured as described above.

4. A vehicle notification method including: acquiring ambient sound in the vehicle interior of the host vehicle; determining the frequency band of a notification sound based on the frequency band of the ambient sound; and executing a notification operation for notifying an occupant of the host vehicle that the host vehicle is in a predetermined state by generating the notification sound in the determined frequency band.

5. A program for causing a computer mounted on a vehicle to execute, wherein the program causes the computer to acquire ambient sound in the vehicle interior of the host vehicle; determine the frequency band of a notification sound based on the frequency band of the ambient sound; and execute a notification operation for notifying an occupant of the host vehicle that the host vehicle is in a predetermined state by generating the notification sound in the determined frequency band. The program is as described above.

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