Warning sound generation device
The warning sound generator adjusts volume based on distance to obstacles, ensuring drivers and pedestrians are alerted to increasing danger through graduated sound changes, addressing the challenge of recognizing risk progression.
Patent Information
- Application Number
- JP2023115733
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-07-14
- Publication Date
- 2025-01-24
AI Technical Summary
Existing warning systems fail to effectively alert drivers to the gradual increase in risk as a vehicle approaches obstacles, making it difficult for drivers to recognize the changing danger level.
A warning sound generator that adjusts the volume of warning sounds based on the distance to the obstacle, using a distance detection device to provide distinct warning signals inside and outside the vehicle, with exponential changes in volume to indicate proximity.
Enhances driver awareness of approaching obstacles by providing graduated volume changes, allowing passengers and pedestrians to easily recognize the increasing risk through distinct warning sounds.
Smart Images
Figure 2025012695000001_ABST
Abstract
Description
[Technical field]
[0001] The present disclosure relates to a warning sound generating device. [Background technology]
[0002] Conventionally, a warning device that warns a vehicle driver of the presence of an obstacle by sound has been known. Patent Document 1 discloses a device that detects a risk level indicating the magnitude of the risk of future contact between the vehicle and the obstacle, and issues different types of warnings to the vehicle driver according to the detected risk level. For example, when the risk level is equal to or lower than a judgment threshold, a notification sound that does not make the driver tense is issued, and when the risk level exceeds the judgment threshold, a warning sound that makes the driver tense is issued. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Japanese Patent Application Publication No. 9-293199 Summary of the Invention [Problem to be solved by the invention]
[0004] In the safe driving support device described in Patent Document 1, it is considered that when the vehicle approaches an obstacle, the generated sound is switched from a notification sound to a warning sound at a certain timing. According to this aspect, there is a problem that it is difficult for the driver to recognize that the danger gradually increases as the vehicle approaches the obstacle.
[0005] Taking the above circumstances into consideration, one aspect of the present disclosure aims to realize a warning sound emitting device that can easily allow a listener of the warning sound to recognize that a vehicle is gradually approaching an object. [Means for solving the problem]
[0006] In order to solve the above problems, a warning sound generating device according to one embodiment of the present disclosure includes a distance information acquisition unit that acquires distance information from a distance detection device that detects the distance between a vehicle and an object, and a sound generating unit that generates a warning signal based on the distance information, and the sound generating unit changes the amount of change per unit distance in the volume or pitch of the warning sound based on the warning signal in accordance with the distance. [Brief description of the drawings]
[0007] [Figure 1] 1 is a configuration diagram showing an example of a warning system according to a first embodiment. [Diagram 2] 11 is a diagram showing an example of the relationship between the volume of a first warning sound and a relative distance. FIG. [Diagram 3] 13 is a diagram showing an example of the relationship between the volume of a second warning sound and a relative distance. FIG. [Figure 4] 2 is a flowchart showing an example of the operation of the warning system of FIG. 1. [Diagram 5] FIG. 11 is a configuration diagram showing an example of a warning system according to a second embodiment. [Figure 6] 13 is a diagram showing an example of a lookup table that defines the relationship between the relative distance and the vehicle speed and the volume of the second warning sound. FIG. [Figure 7] FIG. 13 is a diagram showing an example of the relationship between the pitch of a first warning sound and a relative distance according to a first modified example. [Figure 8] FIG. 11 is a diagram showing an example of the relationship between the pitch of a second warning sound and a relative distance according to a second modified example. [Figure 9] FIG. 13 is a diagram showing an example of the relationship between the pitch of a second warning sound and vehicle speed according to a third modified example. [Figure 10] FIG. 13 is a diagram showing an example of the relationship between the volume of a second warning sound and a relative distance in a fourth modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0008] A: First embodiment A1: Configuration of the warning sound generating device 1 is a configuration diagram showing an example of a warning system 1 according to a first embodiment. The warning system 1 is mounted on a vehicle 100 such as an automobile. The warning system 1 includes a storage device 10, a warning sound generating device 20, a distance detection device 30, an amplifier device 40, and a speaker device 50. The warning system 1 is a system in which a warning signal is supplied from the warning sound generating device 20 through the amplifier device 40 to the speaker device 50, and a sound corresponding to the warning signal is emitted from the speaker device 50 to the inside or outside of the vehicle 100.
[0009] The vehicle 100 is driven by an occupant of the vehicle 100. The vehicle 100 may be autonomously driven without being driven by an occupant of the vehicle 100.
[0010] The storage device 10 is a recording medium readable by a computer (e.g., a non-transitive recording medium readable by a computer). The storage device 10 includes a non-volatile memory and a volatile memory. The non-volatile memory is, for example, a Read Only Memory (ROM), an Erasable Programmable Read Only Memory (EPROM), and an Electrically Erasable Programmable Read Only Memory (EEPROM). The volatile memory is, for example, a Random Access Memory (RAM).
[0011] The storage device 10 stores a program p1 and various information. The program p1 defines the operation of the warning sound generation device 20. The storage device 10 may store the program p1 read from a storage device in a server (not shown). In this case, the storage device in the server is an example of a computer-readable recording medium.
[0012] The warning sound generating device 20 reads the program p1 from the storage device 10. The warning sound generating device 20 executes the program p1 to function as a distance information acquiring unit 21 and a sound generating unit 22. At least one of the distance information acquiring unit 21 and the sound generating unit 22 may be realized by a circuit such as a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), or an FPGA (Field Programmable Gate Array).
[0013] The distance detection device 30 measures the distance between the vehicle 100 and an object present in front of the vehicle 100. The distance detection device 30 has a radar 31 and a camera 32. The object includes a guard rail, a curb, a side wall, another vehicle, a pedestrian, an obstacle on the road, and the like.
[0014] The radar 31 is disposed in a front portion of the vehicle 100, for example, inside the front grill of the vehicle 100. The radar 31 detects the position of an object present in front of the vehicle 100 by irradiating electromagnetic waves in the millimeter wave band to the front of the vehicle 100 and receiving reflected waves of the irradiated electromagnetic waves.
[0015] The camera 32 is disposed in a front portion of the cabin of the vehicle 100, for example, above the windshield. The camera 32 captures an image of the area in front of the vehicle 100.
[0016] The distance detection device 30 may be disposed at the front and rear of the vehicle 100 so as to be able to measure the distance to an object present behind the vehicle 100 in addition to the object present in front of the vehicle 100. The distance detection device 30 does not necessarily have to have both the radar 31 and the camera 32. For example, the distance detection device 30 may have either the radar 31 or the camera 32, or may further have a LiDAR (Light Detection And Ranging) scanner.
[0017] The amplifying device 40 includes a first amplifier 41, a second amplifier 42, and a third amplifier 43. The speaker device 50 includes a first speaker 51, a second speaker 52, and a third speaker 53.
[0018] The first amplifier 41 amplifies the sound signal from the warning sound generating device 20 to a level suitable for driving the first speaker 51. The first amplifier 41 outputs the amplified sound signal as a first amplified signal b1 to the first speaker 51. The second amplifier 42 amplifies the sound signal from the warning sound generating device 20 to a level suitable for driving the second speaker 52. The second amplifier 42 outputs the amplified sound signal as a second amplified signal b2 to the second speaker 52. The third amplifier 43 amplifies the sound signal from the warning sound generating device 20 to a level suitable for driving the third speaker 53. The third amplifier 43 outputs the amplified sound signal as a second amplified signal b2 to the third speaker 53.
[0019] The first speaker 51 is disposed within the passenger compartment of the vehicle 100. The second speaker 52 is disposed below the front bumper of the vehicle 100. The third speaker 53 is disposed below the rear bumper of the vehicle 100.
[0020] When the vehicle 100 is an electric vehicle such as a hybrid vehicle or an electric car, the second speaker 52 and the third speaker 53 may function as part of a vehicle approach notification device that is required to be installed in electric vehicles.
[0021] The distance information acquisition unit 21 acquires distance information from the radar 31 and the camera 32 . More specifically, the distance information acquisition unit 21 receives detection data by the radar 31, and identifies the position and direction of the object from the received detection data. The distance information acquisition unit 21 receives imaging data by the camera 32, and identifies the position and type of the object from the received imaging data using a known image recognition technique. The distance information acquisition unit 21 acquires distance information by calculating a relative distance between the vehicle 100 and the object based on the identified position, direction, type, etc. of the object.
[0022] The sound output unit 22 generates a warning signal as a sound signal based on the distance information. The sound output unit 22 outputs the warning signal generated by the sound output unit 22 to the amplifier device 40. More specifically, the warning signal includes a first warning signal and a second warning signal. The sound output unit 22 outputs the first warning signal to the first amplifier 41. The sound output unit 22 outputs the second warning signal to the second amplifier 42 and the third amplifier 43, respectively.
[0023] The first warning signal a1 is amplified by the first amplifier 41 and output as a first amplified signal b1 to the first speaker 51. The first speaker 51 emits a first warning sound based on the first warning signal a1 toward the interior of the vehicle 100.
[0024] The second warning signal a2 is amplified by the second amplifier 42 and output as a second amplified signal b2 to the second speaker 52. The second warning signal a2 is also amplified by the third amplifier 43 and output as a second amplified signal b2 to the third speaker 53. The second speaker 52 emits a second warning sound based on the second warning signal a2 toward the outside front of the vehicle 100. The third speaker 53 emits the second warning sound based on the second warning signal a2 toward the outside rear of the vehicle 100.
[0025] A2: Characteristics of the first warning sound Fig. 2 is a diagram showing an example of the relationship between the volume of the first warning sound and the relative distance. Fig. 2 shows a curve C1 indicating the change in the volume of the first warning sound with respect to the relative distance. The volume of the first warning sound increases as the relative distance becomes shorter, and the first amount of change increases as the relative distance becomes shorter. The first amount of change is the amount of change in the volume of the first warning sound per unit distance.
[0026] As a representative example, the volume of the first warning sound decreases exponentially with an increase in the relative distance. That is, the first change amount is expressed by an exponential function. The first change amount changes monotonically according to the relative distance. Therefore, the sound generator 22 generates the first warning signal a1 such that the volume of the first warning sound increases as the relative distance decreases, that is, as the vehicle 100 and the object get closer to each other.
[0027] As shown in Fig. 2, the unit of volume is decibels (dB). When the pitch, i.e., frequency, of the first warning sound is constant, the degree of change in the audible volume is considered to be equivalent to the degree of change in volume shown in Fig. 2. Therefore, since the rate of increase in the volume of the first warning sound increases as the vehicle 100 approaches the object, the passengers of the vehicle 100 can more easily recognize the possibility of contact between the vehicle 100 and the object by hearing the first warning sound. Furthermore, when the volume of the first warning sound changes, the pitch of the first warning sound may be constant or may change.
[0028] A3: Characteristics of the second warning sound Fig. 3 is a diagram showing an example of the relationship between the volume of the second warning sound and the relative distance. Fig. 3 shows a curve C2 indicating the change in the volume of the second warning sound with respect to the relative distance. For comparison, a curve C1 indicating the change in the volume of the first warning sound with respect to the relative distance is also shown. The volume of the second warning sound becomes louder as the relative distance becomes shorter, and the second amount of change becomes larger as the relative distance becomes shorter. The second amount of change is the amount of change in the volume of the second warning sound per unit distance.
[0029] As a representative example, the volume of the second warning sound decreases exponentially with an increase in the relative distance. That is, the second change amount is expressed by an exponential function. The second change amount changes monotonically according to the relative distance. Therefore, the sound generator 22 generates the second warning signal a2 so that the shorter the relative distance is, that is, the closer the vehicle 100 and the object are to each other, the louder the second warning sound becomes. As shown in FIG. 3, the unit of volume is decibels (dB). When the pitch, i.e., the frequency, of the second warning sound is constant, the degree of change in the audible volume is considered to be equivalent to the degree of change in volume shown in FIG. 3.
[0030] When the relative distance is within a predetermined range, the first change amount and the second change amount are different from each other. The predetermined range is a range excluding the first end E1 and the second end E2 as shown in Fig. 3. Within the predetermined range, the curve C2 indicating the change in volume of the second warning sound is closer to the vertical axis and the horizontal axis than the curve C1 indicating the change in volume of the first warning sound.
[0031] More specifically, the degree of change of the second amount of change according to the relative distance is smaller in a first range of the predetermined range than the degree of change of the first amount of change according to the relative distance, and is larger in a second range of the predetermined range than the degree of change of the first amount of change according to the relative distance. The second range does not include the first range. Furthermore, the relative distance in the first range is longer than the relative distance in the second range.
[0032] Therefore, when the vehicle 100 approaches the listener to a certain extent, i.e., when the relative distance transitions from the first range to the second range, the listener outside the vehicle 100 hearing the second warning sound will hear the second warning sound suddenly become louder, and will be able to recognize the approach of the vehicle 100.
[0033] A4: Operation explanation Hereinafter, the operation of the warning system 1 will be described with reference to Fig. 4. Fig. 4 is a flow chart showing an example of the operation of the warning sound system 1 of Fig. 1.
[0034] In step S11 , the warning sound generating device 20 functions as the distance information acquiring unit 21 to acquire distance information from the distance detecting device 30 .
[0035] Next, in step S12, the warning sound generating device 20 functions as the sound generating unit 22 to generate a first warning signal a1 based on the distance information.
[0036] Next, in step S13, the warning sound generating device 20 generates a second warning signal a2 based on the distance information by functioning as the sound generating unit 22. The process of step S13 may be executed before the process of step S12. Moreover, the process of step S12 and the process of step S13 may be executed in parallel.
[0037] Next, in step S14, the warning sound generating device 20 functions as the sound generating unit 22 to supply the first warning signal a1 to the first amplifier 41 and the second warning signal a2 to the second amplifier 42 and the third amplifier 43.
[0038] Next, in step S15, the first amplifier 41 generates a first amplified signal b1 based on the first warning signal a1. The second amplifier 42 generates a second amplified signal b2 based on the second warning signal a2. The third amplifier 43 generates a second amplified signal b2 based on the second warning signal a2.
[0039] Next, in step S16, the first speaker 51 emits a first warning sound based on the first warning signal a1, the second speaker 52 emits a second warning sound based on the second warning signal a2, and the third speaker 53 emits a second warning sound based on the second warning signal a2.
[0040] A5: Summary of the first embodiment As described above, the warning sound generation device 20 according to the first embodiment includes the distance information acquisition unit 21 and the sound generation unit 22. The distance information acquisition unit 21 acquires distance information from the distance detection device 30 that detects the distance between the vehicle 100 and an object. The sound generation unit 22 generates a warning signal based on the distance information. The sound generation unit 22 changes the amount of change per unit distance in the volume of the warning sound based on the warning signal in accordance with the distance.
[0041] According to the warning sound generation device 20 of the first embodiment, the amount of change in the volume of the warning sound per unit distance changes according to the distance between the vehicle 100 and the object. Therefore, the listener of the warning sound can easily recognize that the vehicle 100 is gradually approaching the object.
[0042] The warning signal includes a first warning signal a1 and a second warning signal a2. The sound generator 22 generates a first warning sound based on the first warning signal a1 to the inside of the vehicle 100, and generates a second warning sound based on the second warning signal a2 to the outside of the vehicle 100.
[0043] According to this embodiment, passengers in the vehicle cabin can easily recognize that the vehicle 100 is gradually approaching the object, and listeners such as pedestrians around the vehicle 100 can easily recognize that the vehicle 100 is gradually approaching the listener himself / herself.
[0044] Furthermore, when the distance between the vehicle 100 and the object is within a predetermined range, the first change amount and the second change amount are different from each other. The first change amount is the amount of change per unit distance in the volume of the first warning sound. The second change amount is the amount of change per unit distance in the volume of the second warning sound.
[0045] According to this embodiment, the degree of change in the warning sound sounded inside the vehicle cabin and the degree of change in the warning sound sounded outside the vehicle 100 are different from each other, so that the sound generation unit 22 can generate a warning sound appropriate for each environment and situation.
[0046] In addition, the degree of change of the second amount of change according to the relative distance is smaller in a first range of the predetermined range than the degree of change of the first amount of change according to the relative distance, and is larger in a second range of the predetermined range that does not include the first range than the degree of change of the first amount of change according to the relative distance. The relative distance in the first range is longer than the relative distance in the second range.
[0047] According to this embodiment, when the vehicle 100 approaches the target object to a certain extent, the second warning sound emitted outside the vehicle 100 changes in volume more suddenly than the first warning sound emitted inside the vehicle cabin, so that pedestrians and the like around the vehicle 100 can more easily recognize the approach of the vehicle 100.
[0048] Moreover, the first change amount and the second change amount are expressed by exponential functions, and become larger as the relative distance becomes shorter.
[0049] According to this embodiment, the first and second warning sounds change along an exponential curve so that the sound gets louder as the distance gets shorter, so that the listener of the first and second warning sounds can more easily recognize that the vehicle 100 is gradually approaching an object including the listener himself / herself.
[0050] In this embodiment, the sound generator 22 generates the first warning sound for the interior of the vehicle 100 and generates the second warning sound for the exterior of the vehicle 100, but the sound generator 22 may generate either the first warning sound or the second warning sound. In other words, the sound generator 22 may generate either the warning sound for passengers in the vehicle interior or the warning sound for listeners such as pedestrians outside the vehicle.
[0051] In addition, in this embodiment, the sound generator 22 emits the second warning sound from the second speaker 52 and the third speaker 53, but the sound generator 22 may emit the second warning sound from either the second speaker 52 or the third speaker 53. For example, the sound generator 22 may output the second warning signal a2 only to the second amplifier 42 when the vehicle 100 is moving forward, and output the second warning signal a2 only to the third amplifier 43 when the vehicle 100 is moving backward. In other words, the sound generator 22 may emit the second warning sound from the second speaker 52 when the vehicle is moving forward, and emit the second warning sound from the third speaker 53 when the vehicle 100 is moving backward.
[0052] Furthermore, the number of speakers that emit the second warning sound does not necessarily need to be one each at the front and rear of the vehicle 100, and only one may be provided.
[0053] B: Second embodiment Hereinafter, a warning sound generating device according to the second embodiment will be described with reference to Fig. 5 and Fig. 6. In the following description, for the sake of simplicity, the same reference numerals are used for the same components as those in the first embodiment, and the description of their functions may be omitted. In addition, in the following description, for the sake of simplicity, differences between the second embodiment and the first embodiment will be mainly described.
[0054] B1: Configuration of the warning sound generating device The configuration of a warning sound generation device 20A according to the second embodiment will be described below with reference to Fig. 5. Fig. 5 is a configuration diagram showing an example of a warning system 1A according to the second embodiment.
[0055] The warning system 1A is mounted on a vehicle 100 such as an automobile. The warning system 1A includes a storage device 10A, a warning sound generating device 20A, a distance detecting device 30, an amplifier device 40, a speaker device 50, and a speed sensor 60.
[0056] The storage device 10A is a computer-readable recording medium. The storage device 10A includes a nonvolatile memory and a volatile memory. The nonvolatile memory is, for example, a ROM, an EPROM, and an EEPROM. The volatile memory is, for example, a RAM.
[0057] The storage device 10A stores a program p2 and various information. The program p2 defines the operation of the warning sound generation device 20A. The storage device 10A may store the program p2 read from a storage device in a server (not shown). In this case, the storage device in the server is an example of a computer-readable recording medium.
[0058] The warning sound generating device 20A reads the program p2 from the storage device 10A. By executing the program p2, the warning sound generating device 20A functions as a distance information acquiring unit 21, a sound generating unit 22A, and a speed information acquiring unit 23. At least one of the distance information acquiring unit 21, the sound generating unit 22A, and the speed information acquiring unit 23 may be realized by a circuit such as a DSP, an ASIC, a PLD, or an FPGA.
[0059] The speed sensor 60 detects the vehicle speed. The vehicle speed is the speed of the vehicle 100. The speed sensor 60 is disposed near the wheels of the vehicle 100. The speed sensor 60 directly detects the rotation speed of the wheels. The vehicle speed is calculated based on the detected rotation speed of the wheels. The speed sensor 60 is an example of a "speed detection device."
[0060] The speed information acquisition unit 23 acquires speed information from the speed sensor 60. More specifically, the speed information acquisition unit 23 acquires the detection result of the rotation speed of the wheels by the speed sensor 60. The speed information acquisition unit 23 calculates the vehicle speed based on the acquired rotation speed of the wheels and the outer diameter of the wheels stored in advance, and outputs the calculated vehicle speed to the sound generation unit 22A.
[0061] The sound generating unit 22A changes the volume of the second warning sound according to the relative distance and the vehicle speed. More specifically, the sound generating unit 22 calculates the volume of the second warning sound by applying the acquired relative distance and vehicle speed to a lookup table that defines the relationship between the predetermined relative distance and vehicle speed and the volume of the second warning sound.
[0062] B2: Characteristics of the first warning sound The first warning sound generated by the warning sound generating device 20A according to this embodiment is similar to the first warning sound generated by the warning sound generating device 20 according to the first embodiment, and therefore a detailed description thereof will be omitted. As shown in Fig. 2, the volume of the first warning sound increases as the relative distance decreases, and the first amount of change increases as the relative distance decreases. The first amount of change changes monotonically according to the relative distance.
[0063] B3: Characteristics of the second warning sound Fig. 6 is a diagram showing an example of a lookup table that specifies the relationship between the relative distance and vehicle speed and the volume of the second warning sound. As shown in Fig. 6, the volume of the second warning sound increases as the relative distance decreases and increases as the vehicle speed increases. The second change amount changes monotonically according to the relative distance and also changes monotonically according to the vehicle speed. However, when the vehicle speed exceeds a predetermined speed Vp, the second warning sound stops.
[0064] The predetermined speed Vp is defined by the specifications of an acoustic vehicle alerting system (AVAS) (not shown). For example, the predetermined speed Vp is 25 km / h. The vehicle approaching alerting device generates an alert sound toward the outside of the vehicle 100 when the vehicle speed is equal to or lower than the predetermined speed Vp, and stops the alert sound when the vehicle speed exceeds the predetermined speed Vp. The warning sound generating device 20A cooperates with the vehicle approaching alerting device and stops the second warning sound when the vehicle speed exceeds the predetermined speed Vp. Note that the predetermined speed Vp is not limited to 25 km / h.
[0065] B3: Summary of the second embodiment As described above, the warning sound generation device 20A according to the second embodiment further includes the speed information acquisition unit 23. The speed information acquisition unit 23 acquires speed information from the speed sensor 60. The speed sensor 60 detects the speed of the vehicle 100. The sound generation unit 22A changes the volume of the second warning sound depending on the distance and vehicle speed. The speed sensor 60 is an example of a "speed detection device."
[0066] According to this aspect, the volume of the second warning sound is changed not only according to the relative distance but also according to the vehicle speed, so that listeners such as pedestrians around the vehicle can more easily recognize that the vehicle is approaching an object, including the listener themselves.
[0067] In this embodiment, the pitch of the first warning sound and the pitch of the second warning sound are constant, but the pitch may be variable.
[0068] C: Modification The present invention is not limited to the above embodiment, and various modified examples can be adopted within the scope of the present invention. Specific modified examples are exemplified below. Two or more aspects arbitrarily selected from the following examples can be appropriately combined within a range that does not contradict each other. In the modified examples exemplified below, the symbols used in the above explanation are used for elements whose actions and functions are equivalent to those of the above embodiment, and detailed explanations of each are appropriately omitted.
[0069] C1: First modified example In the above embodiment, the volume of the first warning sound changes according to the relative distance, but the pitch of the first warning sound may change according to the relative distance. Fig. 7 is a diagram showing an example of the relationship between the pitch of the first warning sound and the relative distance according to the first modified example. As shown in Fig. 7, the pitch of the first warning sound becomes higher as the relative distance becomes shorter, and the first amount of change becomes higher as the relative distance becomes shorter. The first amount of change is the amount of change in the pitch of the first warning sound per unit distance.
[0070] As a representative example, the pitch of the first warning sound decreases exponentially with increasing relative distance. That is, the first change amount is expressed by an exponential function. In other words, the sound generator 22 generates the first warning signal a1 such that the pitch of the first warning sound becomes higher as the relative distance becomes shorter, that is, as the vehicle 100 and the object get closer to each other.
[0071] As shown in Fig. 7, the unit of pitch is mel. When the volume of the first warning sound is constant, the degree of audible change in pitch is considered to be equivalent to the degree of pitch change shown in Fig. 7. Therefore, since the rate of increase in pitch of the first warning sound increases as the vehicle 100 approaches the object, the passenger of the vehicle 100 can more easily recognize the possibility of contact between the vehicle 100 and the object by hearing the first warning sound. Furthermore, when the pitch of the first warning sound changes, the volume of the first warning sound may be constant or may change.
[0072] C2: Second modified example In the above embodiment, the volume of the second warning sound changes according to the relative distance, but the pitch of the second warning sound may change according to the relative distance. Fig. 8 is a diagram showing an example of the relationship between the pitch of the second warning sound and the relative distance according to the second modified example. As shown in Fig. 8, the pitch of the second warning sound becomes higher as the relative distance becomes shorter, and the second amount of change becomes higher as the relative distance becomes shorter. The second amount of change is the amount of change in the pitch of the second warning sound per unit distance.
[0073] As a representative example, the pitch of the second warning sound decreases exponentially with increasing relative distance. That is, the second change amount is expressed by an exponential function. In other words, the sound generator 22 generates the second warning signal a2 such that the pitch of the second warning sound increases as the relative distance decreases, that is, as the vehicle 100 and the object get closer to each other.
[0074] The above-described embodiment, the first modification, and the second modification may be appropriately combined within a range that does not contradict each other. For example, the volume of the first warning sound may change and the pitch of the second warning sound may change according to the relative distance, or the pitch of the first warning sound may change and the volume of the second warning sound may change according to the relative distance.
[0075] C3: Third modified example In the second embodiment, the sound generating unit 22A changes the volume of the second warning sound according to the vehicle speed, but the pitch of the second warning sound may also be changed according to the vehicle speed. Fig. 9 is a diagram showing an example of the relationship between the pitch of the second warning sound and the vehicle speed according to the third modified example. As shown in Fig. 9, the pitch of the second warning sound becomes higher as the vehicle speed increases, and the second amount of change becomes higher as the vehicle speed increases. However, the sound generating unit 22A stops the second warning sound when the vehicle speed exceeds a predetermined speed Vp.
[0076] As a representative example, the pitch of the second warning sound increases exponentially with increasing vehicle speed. That is, the second change amount is expressed by an exponential function. In other words, the sound generator 22A generates the second warning signal a2 such that the pitch of the second warning sound increases as the vehicle speed increases.
[0077] When the pitch of the second warning sound is changed, the volume of the second warning sound may be constant or may be variable.
[0078] C4: Fourth modified example In the above embodiment, the change in the volume of the second warning sound with respect to the relative distance is expressed by an exponential function, but the change in the volume of the second warning sound with respect to the relative distance may be expressed by a logarithmic function. Fig. 10 is a diagram showing an example of the relationship between the volume of the second warning sound and the relative distance according to the fourth modified example. As shown in Fig. 10, the volume of the second warning sound becomes louder as the relative distance becomes shorter, and the amount of change in the volume of the second warning sound per unit distance becomes smaller as the relative distance becomes shorter.
[0079] The change in pitch of the second warning sound with respect to the relative distance may be represented by a logarithmic function, in which case the pitch of the second warning sound becomes higher as the relative distance becomes shorter, and the amount of change in the pitch of the second warning sound per unit distance becomes smaller as the relative distance becomes shorter.
[0080] According to this embodiment, the second warning sound changes along a logarithmic curve so that the sound becomes louder as the relative distance becomes shorter, so that listeners such as pedestrians around the vehicle can quickly recognize that the vehicle 100 is approaching an object, including the listeners themselves.
[0081] C5: Fifth variant In the second embodiment and the third modified example, the warning sound generation device 20A stops the second warning sound when the vehicle speed exceeds a predetermined speed, but it is not necessary to set an upper limit of the vehicle speed at which the second warning sound is generated. In other words, the warning sound generation device 20A may operate independently of the vehicle approach notification device.
[0082] C6: 6th variant In the above embodiment, the change in the volume or pitch of the first warning sound with respect to the relative distance is expressed by an exponential function, but it does not necessarily have to be an exponential function, and it may be a change that shows a tendency for the first amount of change to increase as the relative distance becomes shorter. For example, it may be expressed by a higher-order function such as a quadratic function, or by another function.
[0083] C7: 7th variant In the above embodiment, the amount of change in the volume or pitch of the first warning sound per unit distance monotonically decreases or increases depending on the relative distance, but it may change in a stepped manner depending on the relative distance. Also, in the above embodiment, the amount of change in the volume or pitch of the second warning sound per unit distance or the amount of change in the volume or pitch of the second warning sound per unit speed monotonically decreases or increases depending on the vehicle speed, but it may change in a stepped manner depending on the vehicle speed.
[0084] D: Notes From the above-described exemplary embodiments, the following configurations can be understood, for example.
[0085] A warning sound generating device according to one aspect (aspect 1) of the present disclosure includes a distance information acquisition unit that acquires distance information from a distance detection device that detects the distance between a vehicle and an object, and a sound generating unit that generates a warning signal based on the distance information, and the sound generating unit changes the amount of change per unit distance in the volume or pitch of the warning sound based on the warning signal in accordance with the distance.
[0086] According to this aspect, the amount of change in the volume or pitch of the warning sound per unit distance varies according to the distance between the vehicle and the object, so that the listener of the warning sound can easily recognize that the vehicle is gradually approaching the object.
[0087] In a warning sound generating device according to one aspect (aspect 2) of the present disclosure, the warning signal includes at least one of a first warning signal and a second warning signal, and the sound generating unit generates a first warning sound based on the first warning signal into the passenger compartment of the vehicle, and generates a second warning sound based on the second warning signal to the outside of the vehicle.
[0088] According to this aspect, passengers in the vehicle can easily recognize that the vehicle is gradually approaching the object, and listeners such as pedestrians around the vehicle can easily recognize that the vehicle is gradually approaching them.
[0089] In a warning sound generating device according to one aspect (aspect 3) of the present disclosure, when the distance is within a predetermined range, a first change amount, which is the amount of change per unit distance in the volume or pitch of the first warning sound, and a second change amount, which is the amount of change per unit distance in the volume or pitch of the second warning sound, are different from each other.
[0090] According to this aspect, the degree of change in the warning sound produced within the vehicle cabin and the degree of change in the warning sound produced outside the vehicle are different from each other, so that the sound production unit can produce a warning sound appropriate for each environment and situation.
[0091] In a warning sound generating device according to one aspect (aspect 4) of the present disclosure, the degree of change of the second amount of change according to the distance is smaller in a first range of the specified range than the degree of change of the first amount of change according to the distance, and is larger than the degree of change of the first amount of change according to the distance in a second range of the specified range that does not include the first range, and the distance in the first range is longer than the distance in the second range.
[0092] According to this embodiment, the degree of change in the warning sound generated inside the vehicle cabin is different from the degree of change in the warning sound generated outside the vehicle. When the vehicle approaches the object to a certain extent, that is, when the distance changes from the first range to the second range, the warning sound generated outside the vehicle changes in volume or pitch more abruptly than the warning sound generated inside the vehicle cabin. Therefore, listeners such as pedestrians around the vehicle can more easily recognize the approach of the vehicle.
[0093] A warning sound generating device according to one aspect (aspect 5) of the present disclosure further includes a speed information acquisition unit that acquires speed information from a speed detection device that detects the speed of the vehicle, and the sound generating unit changes the volume or pitch of the second warning sound depending on the distance and the speed.
[0094] According to this aspect, the change in volume or pitch of the warning sound per unit speed is changed according to the vehicle speed, so that listeners, such as pedestrians around the vehicle, can more easily recognize that the vehicle is approaching an object, including the listener themselves.
[0095] In the warning sound generation device according to one aspect (aspect 6) of the present disclosure, at least one of the first change amount and the second change amount is expressed by an exponential function, and becomes larger as the distance becomes shorter.
[0096] According to this embodiment, at least one of the first warning sound and the second warning sound changes along an exponential curve so that the sound gets louder as the distance gets shorter, so that a listener who hears at least one of the first warning sound and the second warning sound can more easily recognize that the vehicle is gradually approaching an object, including the listener himself / herself.
[0097] In the warning sound generation device according to one aspect (aspect 7) of the present disclosure, the change in the second warning sound with respect to the distance is represented by a logarithmic function, and becomes louder as the distance becomes shorter.
[0098] According to this embodiment, the second warning sound changes along a logarithmic curve so that the sound gets louder as the distance gets shorter, allowing listeners such as pedestrians around the vehicle to quickly recognize that the vehicle is approaching an object, including the listeners themselves. [Explanation of symbols]
[0099] 1,1A...warning system, 10,10A...storage device, 20,20A...warning sound generating device, 21...distance information acquisition unit, 22...sound generation unit, 23...speed information acquisition unit, 30...distance detection device, 60...speed sensor, 100...vehicle, a1...first warning signal, a2...second warning signal, b1...first amplified signal, b2...second amplified signal.
Claims
1. a distance information acquisition unit that acquires distance information from a distance detection device that detects a distance between a vehicle and an object; a sound generator for generating a warning signal based on the distance information; Equipped with The sound generator changes a change amount per unit distance of a volume or a pitch of the warning sound based on the warning signal in accordance with the distance. Alarm sound generator.
2. The warning signal includes at least one of a first warning signal and a second warning signal, The sound generator generates a first warning sound based on the first warning signal to an interior of the vehicle, and generates a second warning sound based on the second warning signal to an exterior of the vehicle.
2. The warning sound generating device according to claim 1.
3. When the distance is within a predetermined range, a first change amount, which is a change amount per unit distance in a volume or a pitch of the first warning sound, and a second change amount, which is a change amount per unit distance in a volume or a pitch of the second warning sound, are different from each other.
3. The warning sound generating device according to claim 2.
4. a degree of change of the second change amount according to the distance is smaller than a degree of change of the first change amount according to the distance in a first range of the predetermined range, and is larger than a degree of change of the first change amount according to the distance in a second range of the predetermined range that does not include the first range, The distance in the first range is greater than the distance in the second range. The warning sound generating device according to claim 3.
5. A speed information acquisition unit that acquires speed information from a speed detection device that detects the speed of the vehicle, The sound generator changes a volume or a pitch of the second warning sound in accordance with the distance and the speed.
3. The warning sound generating device according to claim 2.
6. At least one of the first change amount and the second change amount is expressed by an exponential function, and the first change amount is larger as the distance is shorter. The warning sound generating device according to claim 3.
7. A change in the second warning sound with respect to the distance is represented by a logarithmic function, and the change in the second warning sound becomes larger as the distance becomes shorter. The warning sound generating device according to claim 3.
Citation Information
Patent Citations
Safety traveling supporting device
JP1997293199A