JP2011152856A - Imitation vehicle sound producing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To notify the approach of one's own vehicle to a pedestrian without a sense of incongruity, even in an automobile of a high silence property such as a hybrid vehicle. <P>SOLUTION: A travel state acquiring part acquires a travel state of the vehicle, and a waveform adjusting part produces and adjusts an imitation vehicle sound based on sound source information, and a sound volume adjusting part adjusts a sound volume with every loudspeaker in response to the travel state, and a sound image adjusting part adjusts a sound image in response to the travel state, and an output control unit outputs the imitation vehicle sound to the loudspeaker based on an adjusting result of respective processing parts, and this imitation vehicle sound producing device is constituted so that the outputted imitation vehicle sound uses a vehicle body surface as a surface sound source. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a pseudo vehicle sound generation device capable of notifying a pedestrian of the approach of a host vehicle without a sense of incongruity even for a highly silent automobile such as a hybrid vehicle.

  2. Description of the Related Art Conventionally, a technique for notifying a pedestrian of an approach of a host vehicle or the like from a speaker provided in the vehicle is known in order to prevent personal injury caused by an automobile.

  In recent years, with the increase in environmental protection, automobiles with a high level of silence, such as hybrid cars, are rapidly spreading.

  Such a quiet vehicle can travel without using an internal combustion engine as a power source, and compared with a vehicle using only the internal combustion engine as a power source (hereinafter referred to as a “general engine vehicle”) during such travel. And it boasts exceptional silence.

  Therefore, in recent years, technologies targeting such automobiles with high silence have appeared as techniques for informing the approach of the host vehicle.

  For example, a sound generation device disclosed in Patent Document 1 is a device that is provided in such a highly silent automobile and warns the approach of the host vehicle by emitting a predetermined sound from a speaker. Such speakers are arranged on the front left and right of the vehicle.

  Here, for the predetermined sound, an engine start sound, a running sound, or the like recorded in advance as sample data is used. Hereinafter, such a pseudo vehicle sound will be referred to as a “pseudo vehicle sound”.

  Further, the notification device disclosed in Patent Document 2 is also a device that issues a simulated vehicle sound and notifies the approach of the host vehicle, similarly to the sound generation device of Patent Document 1.

  And the road noise (for example, the friction sound of a tire and a road surface) etc. which were recorded when the own vehicle is drive | working more than predetermined | prescribed speed etc. are used for the pseudo vehicle sound in this patent document 2. FIG. In the technique of Patent Document 2, the speaker is arranged from the lower part of the vehicle body toward the ground.

JP 2004-136831 A JP 2008-120283 A

  However, when the technique of Patent Document 1 is used, the speakers are arranged on the front left and right of the vehicle as described above. Therefore, the position is different from the sound source (for example, engine and exhaust pipe) of an actual general engine vehicle, and there is a problem that even if the simulated vehicle sound is notified, the vehicle sound is uncomfortable.

  In this regard, when the technique disclosed in Patent Document 2 is used, the speaker is disposed at the lower part of the vehicle body along the periphery of the vehicle, so that the same problem occurs. Moreover, since the pseudo vehicle sound of the technology uses road noise at the time of traveling at a predetermined speed or more as described above, it is unsuitable for use as vehicle sound when approaching at a low speed.

  Furthermore, in any of the conventional techniques, since the pseudo vehicle sound is mainly emitted in the traveling direction of the vehicle, there is a problem that the easiness to hear the sound varies depending on the place. That is, there are cases where it is difficult to hear at a predetermined location around the vehicle, for example, in a direction opposite to the direction of the speaker, and the actual vehicle sound of a general engine vehicle is still uncomfortable.

  From these facts, how to realize a pseudo vehicle sound generation device capable of notifying a pedestrian of the approach of the host vehicle without a sense of incongruity even for a highly silent vehicle such as a hybrid vehicle is significant. It has become a challenge.

  The present invention has been made to solve the above-described problems caused by the prior art, and even if the vehicle is highly silent, such as a hybrid vehicle, the approach of the host vehicle can be notified without a sense of incongruity to a pedestrian. It is an object of the present invention to provide a pseudo vehicle sound generation device that can be used.

  In order to solve the above-described problems and achieve the object, the present invention is a pseudo vehicle sound generating device that emits a pseudo vehicle sound that simulates a vehicle sound, and includes a surface in contact with the outside of a structure constituting the vehicle. It is provided inside the enclosed closed space or the semi-closed space, and is provided with output means for outputting the simulated vehicle sound.

  According to the present invention, the vehicle is provided in a closed space or quasi-closed space including a surface in contact with the outside of the structure constituting the vehicle, and outputs pseudo vehicle sound. Even if it is a car with high property, there exists an effect that the approach of the own vehicle can be alert | reported without a sense of incongruity with respect to a pedestrian.

FIG. 1 is a diagram showing an outline of a pseudo vehicle sound generation method according to the present invention. FIG. 2 is a diagram for explaining surface sound source generation using a point sound source. FIG. 3 is a block diagram illustrating the configuration of the simulated vehicle sound reproducing device according to the present embodiment. FIG. 4 is a diagram illustrating an arrangement example of speakers. FIG. 5 is a diagram for explaining the waveform adjustment processing of the waveform adjustment unit. FIG. 6 is a diagram for explaining the volume adjustment processing of the volume adjustment unit. FIG. 7 is a diagram for explaining the sound image adjustment processing of the sound image control unit. FIG. 8 is a diagram for explaining the directivity control process when the speaker is disposed inside the side of the vehicle. FIG. 9 is a flowchart showing a processing procedure of processing executed by the simulated vehicle sound reproducing device.

  Exemplary embodiments of a pseudo vehicle sound generation method according to the present invention will be described below in detail with reference to the accompanying drawings. In the following, the outline of the pseudo vehicle sound generation method according to the present invention will be described with reference to FIGS. 1 and 2, and then an embodiment of the pseudo vehicle sound generation device to which the pseudo vehicle sound generation method according to the present invention is applied will be described. Will be described with reference to FIGS.

  Hereinafter, the predetermined sound pressure of the pseudo vehicle sound is described as the sound pressure 1 of the closed curve. It is assumed that the pseudo vehicle sound having the same volume can be heard at the outer peripheral portion of the sound pressure 1. In addition, the presence of a reflector outside the vehicle that reflects the simulated vehicle sound is not considered.

  In the following, a case will be described in which the vehicle including the pseudo vehicle sound generation device according to the present invention is a hybrid vehicle with high silence.

  First, an outline of a pseudo vehicle sound generation method according to the present invention will be described with reference to FIG. FIG. 1 is a diagram showing an outline of a pseudo vehicle sound generation method according to the present invention. Incidentally, (A) in the figure shows the problems of the conventional pseudo vehicle sound generation method, and (B) in the figure shows the characteristics of the pseudo vehicle sound generation method according to the present invention.

  As shown in FIG. 1A, according to the conventional method, there is a problem that the sound pressure around the vehicle is biased. Hereinafter, this point will be specifically described.

  As shown to (Aa) of the figure, according to the conventional method, since the sound source that emits the pseudo vehicle sound is a point sound source, the pseudo vehicle sound is concentrated in the vicinity of the point sound source. For example, (Aa) in the figure shows a case where one front speaker 13 f is arranged in front of the vehicle 50.

  In such a case, the pseudo vehicle sound emitted from the front speaker 13f is concentrated in the vicinity of the front speaker 13f. Therefore, at a point far from the sound pressure 1, for example, behind the vehicle 50, the pseudo vehicle sound is difficult to hear.

  In addition, it is said that the sound pressure of the vehicle sound emitted from a normal general engine vehicle is distributed almost evenly around the vehicle. Therefore, the simulated vehicle sound according to the conventional method is uncomfortable as compared with the actual vehicle sound.

  Further, as shown in (A-b) of the figure, even in the traveling vehicle 50, the sound pressure 1 of the pseudo vehicle sound was biased. Note that (Ab) in the figure shows a case where the vehicle 50 moves forward in the traveling direction shown in the figure.

  That is, during the forward movement of the vehicle 50, the pseudo vehicle sound emitted from the front speaker 13f tends to be difficult to hear in front of the vehicle 50 and easy to hear in the rear (sound pressure of (A-b) in the figure). 1).

  Therefore, as shown in FIG. 5B, in the pseudo vehicle sound generation method according to the present invention, the deviation of the sound pressure 1 is reduced and equalized around the vehicle. Here, in the simulated vehicle sound generation method according to the present invention, the following two methods are employed as methods for reducing the deviation of the sound pressure 1.

  First, as a first method, in the simulated vehicle sound generation method according to the present invention, the vehicle body surface of the vehicle 50 is converted to a surface sound source (see (Ba) in the figure). Specifically, a point sound source is arranged inside the vehicle 50, and the vehicle body surface of the vehicle 50 is vibrated by sound emitted from the point sound source, and the vehicle body surface is used as a surface sound source. Details of this point will be described later with reference to FIG.

  In (Ba) of the figure, a front speaker 13f is arranged inside the front of the vehicle 50, a rear speaker 13b is arranged inside the rear, and two vehicle body surfaces in the vicinity of each speaker are used as surface sound sources. The example which reduces the bias | inclination of the sound pressure 1 is shown. That is, in (Ba) of the figure, the sound pressure 1 is prevented from being biased to a part of the vehicle 50 by using two surface sound sources.

  As a second method, in the pseudo vehicle sound generation method according to the present invention, the deviation of the sound pressure 1 of the pseudo vehicle sound during traveling is reduced (see (B-b) in the figure). Specifically, when the vehicle 50 travels, the sound pressure 1 that deviates in the direction opposite to the traveling direction is returned to the traveling direction side by sound image control using a plurality of surface sound sources.

  For example, (Bb) in the figure shows a case where the vehicle 50 moves forward with the speaker arrangement shown in (Ba) in the figure. In such a case, the pseudo vehicle sound generation device controls the phase of the front speaker 13f and the rear speaker 13b while relatively increasing the volume of the front speaker 13f relative to the volume of the rear speaker 13b, so that the sound pressure 1 is reduced to the vehicle. It controls so that it may be distributed uniformly to 50 whole. Details of this point will be described later with reference to FIGS.

  Here, the surface sound source conversion using the point sound source shown in (Ba) of FIG. 1 will be described in more detail with reference to FIG. FIG. 2 is a diagram for explaining surface sound source generation using a point sound source. (A) in the figure shows an example of arrangement of point sound sources, (B) in the figure shows the principle of surface sound source, and (C) in FIG. , Respectively. The arrangement of the front speaker 13f and the rear speaker 13b is the same as that shown in FIG.

  As shown in FIG. 2A, in the pseudo vehicle sound generation method according to the present invention, point sound sources such as the front speaker 13 f and the rear speaker 13 b are arranged inside the vehicle 50. For example, FIG. 5A shows an example in which a front speaker 13f is arranged in the engine room 50e of the vehicle 50 and a rear speaker 13b is arranged in the trunk room 50t.

  Then, as shown in FIG. 5B, in the simulated vehicle sound generation method according to the present invention, the vehicle body surface of the vehicle 50 is vibrated by the sound generated by the point sound source, and the vehicle body surface is converted into a surface sound source. To do. In addition, what was shown to (B) of the figure is the expansion schematic of the engine room 50e enclosed by the closed curve f shown to (A) of the figure.

  First, as shown in (B-1) of the figure, when the simulated vehicle sound is emitted from the front speaker 13f, the sound wave 20 of the simulated vehicle sound is radiated into the engine room 50e. Here, the engine room 50e is a so-called closed space formed by the engine room top surface 50e-t and the partition wall W. Therefore, the sound wave 20 collides with each surface forming the closed space and vibrates each surface. Although the figure shows the case where the point sound source is provided in the closed space, the point sound source does not need to be completely closed, and the point sound source is arranged in a semi-closed space partially opened to the outside. It is good.

  And as shown to (B-2) of the figure, engine room top surface 50e-t turns into a diaphragm by this vibration, and this engine room top surface 50e-t radiates | emits the sound wave 20 as a sound source. . That is, the sound emitted from the front speaker 13f, which is a point sound source, is converted into a sound having the engine room top surface 50e-t as a surface sound source. The hatched portion of the engine room top surface 50e-t represents a state where the surface 50e-t has been converted into a surface sound source.

  And as shown to (C) of the figure, the engine room top surface 50e-t and the trunk room top surface 50t-t of the vehicle 50 will finally become a surface sound source, and it is wider than such a point sound source. By emitting the pseudo vehicle sound from the surface sound source, the sound pressure 1 in the vicinity of the vehicle 50 can be equalized.

  In the above description, the case where two point sound sources are arranged inside the vehicle 50 has been described. However, more point sound sources may be arranged so that the entire vehicle body of the vehicle 50 becomes a surface sound source. . Moreover, it is good also as arrange | positioning only one point sound source and propagating the sound which this point sound source emitted to the wide range of the vehicle body surface.

  As described above, according to the pseudo vehicle sound generation method according to the present invention, the deviation of the sound pressure 1 of the pseudo vehicle sound can be reduced by converting the vehicle body surface of the vehicle 50 into a surface sound source. Sound pressure distribution similar to vehicle sound can be realized. Further, according to the pseudo vehicle sound generation method according to the present invention, when the vehicle is traveling, the sound pressure 1 during traveling is controlled by moving the position of the sound image obtained by synthesizing the plurality of surface sound sources to an arbitrary position. The bias can also be reduced. Therefore, even if the vehicle is highly silent such as a hybrid vehicle, the approach of the host vehicle can be notified to the pedestrian without a sense of incongruity.

  Below, the Example about the pseudo vehicle sound generation apparatus to which the pseudo vehicle sound generation method demonstrated using FIG. 1 and FIG. 2 is applied is described in detail. Hereinafter, a case will be described in which the simulated vehicle sound generation device is a simulated vehicle sound reproduction device that reproduces simulated vehicle sound based on sound source information.

  First, the configuration of the simulated vehicle sound reproducing apparatus according to the present embodiment will be described with reference to FIG. FIG. 3 is a block diagram illustrating a configuration of the simulated vehicle sound reproducing device 10 according to the present embodiment. In the figure, only components necessary for explaining the characteristics of the pseudo vehicle sound reproducing device 10 are shown, and descriptions of general components are omitted.

  As shown in the figure, the simulated vehicle sound reproducing device 10 includes a speed sensor 11, a gear sensor 12, a speaker 13, a control unit 14, and a storage unit 15. The control unit 14 further includes a traveling condition acquisition unit 14a, a waveform adjustment unit 14b, a volume adjustment unit 14c, a sound image adjustment unit 14d, and an output control unit 14e. And the memory | storage part 15 memorize | stores the sound source information 15a.

  The speed sensor 11 is an input device that detects the vehicle speed of the vehicle 50 and notifies the traveling state acquisition unit 14a. The gear sensor 12 is an input device that detects the gear position of the vehicle 50 and notifies the traveling state acquisition unit 14a.

  In addition to the speed sensor 11 and the gear sensor 12, the pseudo vehicle sound reproducing device 10 includes a large number of input devices that detect the traveling state of the vehicle 50 (for example, a headlight lighting sensor). Therefore, in the simulated vehicle sound reproducing device 10, various traveling state detection devices operate in parallel.

  The speaker 13 is an output device that is disposed inside the vehicle 50 and outputs an electric signal of pseudo vehicle sound input from the output control unit 14e as sound. The structure of the speaker 13 is not particularly limited as long as it can convert an electric signal into sound. For example, a vibrator (hereinafter referred to as “exciter”) may be driven and a surface near the exciter may be used as a diaphragm.

  In the present embodiment, the case where the speaker 13 is a general cone speaker will be described.

  Here, the example of arrangement | positioning of this speaker 13 is demonstrated using FIG. FIG. 4 is a diagram illustrating an arrangement example of the speakers 13. Note that (A) in the figure shows an arrangement example when the vehicle 50 is viewed from above, and (B) and (C) in the figure show arrangement examples when the vehicle 50 is seen from the horizontal direction. , Respectively. Moreover, in the same figure, although each speaker is represented with the broken line, this has shown that each speaker is arrange | positioned inside the vehicle 50. FIG.

  As shown to (A) of the figure, the speaker 13 can be arrange | positioned before and behind the vehicle 50, and right and left. For example, as shown to (Aa) of the figure, the front speaker 13f can be arrange | positioned inside vehicles 50, such as an engine room, and the back speaker 13b can each be arrange | positioned inside vehicles 50, such as a trunk room, respectively.

  Further, as shown in (A-b) of the figure, the left speaker 13l may be arranged inside the left side of the vehicle 50, and the right speaker 13r may be arranged inside the right side of the vehicle 50, respectively. In such a case, the pseudo vehicle sound reproducing device 10 performs directivity control for directing the output sound of each speaker in the front-rear direction of the vehicle 50. Details of this point will be described later with reference to FIG.

  By the way, in (A) of the same figure, although each speaker is shown about the case where the front-back direction or the left-right direction of the vehicle 50 is arrange | positioned as a sound production | generation direction, each sound speaker is sounding direction in the upward direction of the vehicle 50. It is good also as arranging as.

  For example, as shown to (B) of the figure, it is good also as arrange | positioning the ceiling speaker 13t inside the ceiling of the vehicle 50, and making the upward direction of the vehicle 50 into a sounding direction. Thereby, the feeling of sound expansion can be increased. Further, as shown in FIG. 5C, the front speaker 13f may be disposed in the engine room, the rear speaker 13b may be disposed in the trunk room, and the upward direction of the vehicle 50 may be arranged as the sound generation direction.

  In the present embodiment, a case will be described in which the arrangement of the speakers 13 is the same as the arrangement example shown in FIG.

  Returning to the description of FIG. 3, the control unit 14 is a processing unit that adjusts the volume and sound image of each speaker based on the traveling state of the vehicle 50 and outputs a pseudo vehicle sound to the speaker 13. .

  The traveling state acquisition unit 14 a is a processing unit that performs processing for acquiring the traveling state of the vehicle 50 from a detection device such as the speed sensor 11 or the gear sensor 12. Moreover, the driving | running | working condition acquisition part 14a is also a process part which performs the process which determines whether a pseudo vehicle sound is output.

  Specifically, the traveling state acquisition unit 14a determines whether the EV traveling is being performed based on the acquired traveling state. Note that EV traveling refers to a state in which a hybrid vehicle or the like is traveling only by a motor while the engine rotation is stopped. Therefore, if the vehicle 50 is in the EV traveling state, the traveling state acquisition unit 14a determines that the traveling state requires a pseudo vehicle sound output.

  In addition, the traveling state acquisition unit 14a determines whether or not the vehicle speed is equal to or lower than a predetermined speed. Such a predetermined speed is a speed at which a certain amount of vehicle sound such as road noise is generated even when the vehicle 50 is traveling on EV, and is generally said to be 20 km / h. Therefore, if the vehicle speed is 20 km or less per hour, the traveling state acquisition unit 14a determines that the traveling state requires a pseudo vehicle sound output.

  The traveling state acquisition unit 14a is also a processing unit that notifies the acquired traveling state of the vehicle 50 to the volume adjustment unit 14c and the sound image adjustment unit 14d.

  The waveform adjustment unit 14 b is a processing unit that performs waveform adjustment using the sound source information 15 a of the storage unit 15 as an input source, and performs pseudo vehicle sound generation processing and adjustment processing for each speaker 13. Such pseudo vehicle sound generation processing and adjustment processing will be simply referred to as “waveform adjustment processing” below.

  Here, the contents of the waveform adjustment processing performed by the waveform adjustment unit 14b will be described in more detail with reference to FIG. FIG. 5 is a diagram for explaining the waveform adjustment processing of the waveform adjustment unit 14b. Note that (A) in the figure shows a case in which different pseudo vehicle sounds are output for each speaker 13, and (B) in the same figure shows a case in which similar pseudo vehicle sounds are output in all the speakers 13. (C) in the figure shows the contents of the sound source information 15a.

  In FIG. 5B, the size of the circle indicating the engine sound or the like represents the size of the ratio of each sound constituting the pseudo vehicle sound.

  As shown to (A) of the figure, the pseudo vehicle sound reproduction apparatus 10 can output a different pseudo vehicle sound for each speaker 13. For example, FIG. 6A shows a case where engine sound is output from the front speaker 13f and exhaust sound is output from the rear speaker 13b.

  In such a case, the waveform adjustment unit 14b adjusts the waveform using the sound source information 15a as an input source, and generates an engine sound for the front speaker 13f and an exhaust sound for the rear speaker 13b.

  Moreover, as shown to (B) of the figure, the pseudo vehicle sound reproducing | regenerating apparatus 10 can also output the similar pseudo vehicle sound with all the speakers 13. FIG. For example, FIG. 5B shows a case where pseudo vehicle sound composed of engine sound and exhaust sound is output from both the front speaker 13f and the rear speaker 13b.

  In such a case, the waveform adjustment unit 14b generates a pseudo vehicle sound composed of the engine sound and the exhaust sound for both speakers, and configures the pseudo vehicle sound for each speaker 13 by equalizing the pseudo vehicle sound. Adjustments such as changing the ratio of each sound to be performed can also be made.

  For example, as shown in (B) of the figure, the waveform adjustment unit 14b performs an adjustment to make the engine sound ratio larger than the exhaust sound ratio for the front speaker 13f arranged forward. Similarly, the rear speaker 13b disposed rearward is adjusted to make the ratio of exhaust sound larger than the ratio of engine sound.

  Thus, a pseudo vehicle sound with a large engine sound is output in the vicinity of the front speaker 13f, and a pseudo vehicle sound with a large exhaust sound is output in the vicinity of the rear speaker 13b, so that the approach of the vehicle 50 is more realistic. It is possible to notify with vehicle sound.

  The waveform adjustment unit 14b performs the waveform adjustment process using the sound source information 15a as an input source as described above. Here, the sound source information 15a will be described.

  As shown in FIG. 5C, the sound source information 15a is composed of various sound sources that are the generation source of the pseudo vehicle sound. For example, as shown in (C-a) of the figure, individual sound sources such as engine sound 15aa and exhaust sound 15ab can be stored in sound source information 15a in advance.

  And the waveform adjustment part 14b performs generation | occurrence | production and adjustment of a pseudo vehicle sound by performing reading of this separate sound source, synthesis | combination, etc.

  The sound source information 15a may be configured as a single sound source. For example, as shown in (Cb) of the figure, the sound source information 15a may be composed only of the source sound 15ac.

  In such a case, the waveform adjustment unit 14b performs tone color synthesis and the like by operating the original waveform of the source sound 15ac, and generates and adjusts the pseudo vehicle sound.

  The format of the sound source stored in the sound source information 15a is not particularly limited. Therefore, it may be an analog sound source or a digital sound source. Further, it may be a sampling sound source recorded in advance or an artificially synthesized sound source.

  The means for the waveform adjustment process described above is not particularly limited. Therefore, various effectors such as an equalizer may be used, or software control may be performed.

  Returning to the description of FIG. 3, the volume adjusting unit 14 c adjusts the volume of the pseudo vehicle sound generated by the waveform adjusting unit 14 b for each speaker 13 based on the traveling state of the vehicle 50 notified from the traveling state acquiring unit 14 a. A processing unit that performs processing.

  The volume adjustment unit 14c is also a processing unit that performs a process of notifying the output control unit 14e of the volume adjustment result.

  Here, the content of the volume adjustment processing performed by the volume adjustment unit 14c will be described in more detail with reference to FIG. FIG. 6 is a diagram for explaining the volume adjustment processing of the volume adjustment unit 14c. In addition, (A) in the figure shows a case where a pseudo vehicle sound is output during daytime driving, and (B) in the same figure shows a case where a pseudo vehicle sound is output during night driving. Show.

  In addition, the size of the front speaker 13f and the rear speaker 13b shown in the figure represents the relative volume level. Therefore, when the front speaker 13f is shown larger than the rear speaker 13b, it is assumed that the volume of the front speaker 13f is larger than the volume of the rear speaker 13b.

  In addition, for the sake of convenience, the front speaker 13f and the rear speaker 13b in the figure are illustrated as being disposed outside the vehicle, but are actually disposed inside the vehicle 50.

  As shown in FIG. 5A, during the daytime traveling, the volume control unit 14c adjusts the volume for each speaker 13 according to the forward / backward movement of the vehicle 50.

  First, the case where the vehicle 50 moves forward as shown in FIG. As shown to (A-a1) of the figure, when the vehicle 50 starts advancing, the sound pressure 1 will shift | deviate to the reverse direction (back of the vehicle 50) shown in the figure. Note that the sound volume of the front speaker 13f and the rear speaker 13b at this time is the same.

  Therefore, as shown in (A-a2) of the figure, the volume adjustment unit 14c performs a volume adjustment process for raising the volume of the front speaker 13f relative to the volume of the rear speaker 13b. Thereby, the deviation of the sound pressure 1 generated at the start of traveling is reduced.

  Further, also when the vehicle 50 moves backward as shown in (A-b) of the figure, the volume adjusting unit 14c performs the same volume adjusting process. That is, as shown in (A-b1) in the figure, when the vehicle 50 starts to move backward, the sound pressure 1 shifts in the direction opposite to the traveling direction shown in the figure (in front of the vehicle 50). .

  Therefore, as shown in (A-b2) of the figure, the volume adjustment unit 14c performs a volume adjustment process for raising the volume of the rear speaker 13b relative to the volume of the front speaker 13f. Thereby, the deviation of the sound pressure 1 generated at the start of traveling is reduced.

  In addition, as shown in FIG. 5B, the volume adjusting unit 14c adjusts the volume for each speaker 13 in accordance with lighting of the headlight of the vehicle 50 even during night driving. In FIG. 5B, the headlight 100 is illustrated by showing the headlight light 100.

  For example, as shown in (B-1) of the figure, it is assumed that the vehicle 50 is moving forward with the headlights turned on. In addition, in order to make the following description easy to understand, it is assumed that the sound volume of the front speaker 13f and the rear speaker 13b at this time is equal and the sound pressure 1 is not biased.

  In such a case, as shown in (B-2) of the figure, the volume adjustment unit 14c performs a volume adjustment process that raises the volume of the rear speaker 13b relative to the volume of the front speaker 13f. As a result, the sound pressure 1 of the pseudo vehicle sound is biased toward the rear of the vehicle 50 (see the sound pressure 1 in the figure). Can be notified of the approach of the host vehicle by means of a pseudo vehicle sound.

  In addition, although (B) of the figure shows the case where the vehicle 50 is moving forward at night, the volume adjusting unit 14c also performs the same volume adjustment processing as when moving forward at the time of moving backward at night. I do. That is, as described above, the front of the vehicle 50 can notify the approach of the host vehicle by irradiating the headlight light 100, so that the volume adjusting unit 14c sets the volume of the rear speaker 13b to be higher than the volume of the front speaker 13f. A volume adjustment process for relatively increasing the volume is performed.

  Returning to the description of FIG. 3, the sound image adjustment unit 14 d localizes the sound image of the pseudo vehicle sound generated by the waveform adjustment unit 14 b to an arbitrary position based on the traveling state of the vehicle 50 notified from the traveling state acquisition unit 14 a. A processing unit that performs processing. Details of this point will be described later with reference to FIG.

  The sound image adjustment unit 14d is also a processing unit that performs a process of notifying the output control unit 14e of the sound image adjustment result.

  Here, the contents of the sound image adjustment process performed by the sound image adjustment unit 14d will be described in more detail with reference to FIG. FIG. 7 is a diagram for explaining the sound image adjustment processing of the sound image adjustment unit 14d. Note that (A) in the figure shows an outline of sound image adjustment, (B) in the figure shows sound image adjustment at the time of forward movement, and (C) in the figure shows sound image adjustment at the time of backward movement. ing. In the figure, the sound image 200 is illustrated as a star, and the volume of each speaker is the same.

  As shown to (A) of the figure, since the front speaker 13f and the rear speaker 13b are separate sound sources, in order to notify the listener (for example, a pedestrian) of the pseudo vehicle sound without a sense of incongruity, It is necessary to localize the sound image from the sound source.

  Therefore, the sound image adjustment unit 14d localizes the sound image of the pseudo vehicle sound at an arbitrary position. Specifically, the sound image can be localized (or moved) by controlling the phase of the front speaker 13f and the rear speaker 13b.

  For example, as shown in FIG. 5A, the sound image adjustment unit 14d individually adjusts the output timing of the pseudo vehicle sound output from the front speaker 13f and the rear speaker 13b, and converts the sound image 200 of the vehicle 50. It can be localized near the center.

  Further, as shown in (B) of the figure, when the vehicle 50 is moving forward in the traveling direction shown in the figure, the sound image adjusting unit 14d causes the output timing of the front speaker 13f to precede the rear speaker 13b. The sound image 200 is localized in front of the vehicle 50 (that is, the sound image 200 is moved in the direction 400). Thereby, the approach of the own vehicle can be effectively notified to the pedestrian 300 located in the traveling direction shown in FIG.

  Further, as shown in (C) of the figure, when the vehicle 50 is moving backward in the traveling direction shown in the figure, the sound image adjusting unit 14d causes the output timing of the rear speaker 13b to precede the front speaker 13f. The sound image 200 is localized to the rear of the vehicle 50 (that is, the sound image 200 is moved in the direction 500). Thereby, the approach of the own vehicle can be effectively notified to the pedestrian 300 located in the traveling direction shown in FIG.

  Note that the means for adjusting the output timing is not particularly limited. Therefore, the output timing of each speaker 13 may be shifted in software, or an effector such as a delay may be used in hardware.

  In addition, until now, the sound volume control processing has been individually described with reference to FIG. 6 and the sound image control processing has been individually described with reference to FIG. 7, but the pseudo vehicle sound reproduction device 10 adjusts these processing to each other. By doing so, the sound pressure 1 is controlled to be evenly distributed throughout the vehicle 50 even during traveling.

  Returning to the description of FIG. 3, the output control unit 14 e is a processing unit that performs a process of outputting the pseudo vehicle sound that has been adjusted by the volume adjustment unit 14 c and the sound image adjustment unit 14 d to the speaker 13.

  The storage unit 15 is a storage unit configured by a storage device such as a hard disk drive, a nonvolatile memory, or a register, and stores sound source information 15a.

  The sound source information 15a is an input source when the waveform adjustment unit 14b generates a pseudo vehicle sound. Since the contents of the sound source information 15a have already been described with reference to FIG. 5, description thereof is omitted here.

  By the way, although the case where the speaker 13 was arrange | positioned so far to the front inside and the back inside of the vehicle 50 was demonstrated so far, it is good also as this speaker 13 being arrange | positioned inside the side of the vehicle 50 (FIG. 4). (See (Ab)). In such a case, the pseudo vehicle sound is output from the side of the vehicle 50, and the pseudo vehicle sound may be directed in the front-rear direction, for example, according to the traveling direction of the vehicle 50.

  Therefore, hereinafter, directivity control processing when the speaker 13 is disposed inside the side of the vehicle 50 will be described with reference to FIG. FIG. 8 is a diagram for describing directivity control processing when the speaker 13 is disposed inside the side of the vehicle 50.

  As shown in the figure, when the left speaker 13l is arranged inside the left side of the vehicle 50 and the right speaker 13r is arranged inside the right side, the simulated vehicle sound reproducing device 10 outputs the output sound of each speaker to an arbitrary Perform directivity control in the direction. Here, the case where the output sound is directed in the front-rear direction of the vehicle 50 will be mainly described.

  Specifically, the pseudo vehicle sound reproducing device 10 can obtain arbitrary directivity by performing phase control of the output signal of each speaker.

  For example, by performing phase control of the left speaker 13l and the right speaker 13r shown in the figure, the pseudo vehicle sound can be directed to both the front sound image 200f and the rear sound image 200b. Further, it can be directed in one direction only in the direction of the front sound image 200f or only in the direction of the rear sound image 200b.

  Thus, even when the speaker 13 is disposed inside the side of the vehicle 50, the output sound of each speaker is directed in the front-rear direction of the vehicle 50, and the vehicle approaches the pedestrian located in the front-rear direction. Can be notified.

  Further, as described above, when traveling at night, the approach of the host vehicle can be notified to the front of the vehicle 50 by irradiating headlight light (see FIG. 6B). Therefore, in such a case, the output sound of each speaker may be directed only to the rear of the vehicle 50 (in the direction of the sound image 200b in FIG. 8).

  In this directivity control, the sound generation direction may be changed as appropriate using the movable speaker 13. In such a case, for example, the speaker 13 may be provided with a rotation mechanism having the rotation axis as a fulcrum. The phase control of the output signal described above and the movement of the speaker 13 may be combined.

  Next, a processing procedure executed by the simulated vehicle sound reproducing device 10 will be described with reference to FIG. FIG. 9 is a flowchart showing a processing procedure executed by the simulated vehicle sound reproducing device 10.

  As shown in FIG. 9, the simulated vehicle sound reproducing device 10 acquires the traveling state of the vehicle 50 (step S101). Such traveling conditions include various information such as vehicle speed, gear position, and whether or not the headlight is on.

  Then, the simulated vehicle sound reproducing device 10 determines whether or not the vehicle 50 is traveling on EV (step S102). If the vehicle is traveling in EV (step S102, Yes), the pseudo vehicle sound reproducing device 10 shifts the control to the next step S103.

  Moreover, when the determination condition of step S102 is not satisfied (step S102, No), the pseudo vehicle sound reproducing device 10 ends the process.

  Subsequently, the pseudo vehicle sound reproducing device 10 determines whether or not the vehicle speed is 20 km / h or less (step S103). Note that, as described above, when traveling at a speed exceeding 20 km / h, it is said that even a quiet vehicle has the same ease of being noticed as a general engine vehicle, and the pseudo vehicle sound reproducing device 10 is subject to processing. It is outside.

  Therefore, when the vehicle speed is 20 km or less (step S103, Yes), the pseudo vehicle sound reproducing device 10 shifts the control to the next step S104. Moreover, when the determination conditions of step S103 are not satisfied (step S103, No), the pseudo vehicle sound reproducing device 10 ends the process.

  Subsequently, the simulated vehicle sound reproducing device 10 generates a simulated vehicle sound using the sound source information 15a as an input source (step S104). And according to the driving | running | working condition acquired in step S101, a volume is adjusted for every speaker (step S105) (refer FIG. 6).

  Then, the pseudo vehicle sound reproducing device 10 similarly adjusts the sound image according to the traveling state (step S106) (see FIG. 7), and then outputs the pseudo vehicle sound from each speaker (step S107).

  In addition, the pseudo vehicle sound reproducing device 10 repeats the processing after step S101 after performing the processing of step S107. When the pseudo vehicle sound reproducing device 10 determines that it is not necessary to notify the approach of the host vehicle (No in Step S102 or Step S103, No), the process ends.

  As described above, in this embodiment, the traveling state acquisition unit acquires the traveling state of the vehicle, the waveform adjustment unit generates and adjusts the pseudo vehicle sound based on the sound source information, and the volume adjustment unit The volume is adjusted for each speaker according to the situation, the sound image adjustment unit adjusts the sound image according to the driving situation, and the output control unit outputs the pseudo vehicle sound to the speaker based on the adjustment result of each processing unit. The pseudo vehicle sound reproducing device is configured so that the output pseudo vehicle sound uses the vehicle body surface as a surface sound source. Therefore, even if the vehicle is highly silent such as a hybrid vehicle, the approach of the host vehicle can be notified to the pedestrian without a sense of incongruity.

  In the above-described embodiments, the case where the sounding body included in the pseudo vehicle sound reproducing device according to the present invention is a general cone speaker has been described. However, the sounding body outputs sound by driving the exciter. It may be a vibration speaker.

  In such a case, the surface sound source of the vehicle body surface described above can be made by using the exciter to drive the vehicle body surface as a diaphragm (see FIG. 2).

  In the above-described embodiment, the control of the volume and the sound image with respect to the front-rear direction of the vehicle has been described. However, the control of the volume and the sound image with respect to the traveling direction including the oblique direction may be performed. In such a case, the steering angle of the steering wheel is acquired together with the gear position and speed of the vehicle, the traveling direction is specified from the acquired traveling condition, and the volume and sound image for the traveling direction are controlled. .

  As described above, the pseudo vehicle sound generation device according to the present invention is useful when it is desired to notify the pedestrian of the approach of the own vehicle without a sense of incongruity, even in a quiet vehicle such as a hybrid vehicle. In particular, it is suitable for application to a notification device such as an electric vehicle, which is expected to be further spread in the future.

DESCRIPTION OF SYMBOLS 1 Sound pressure 10 Pseudo vehicle sound reproduction apparatus 11 Speed sensor 12 Gear sensor 13 Speaker 13f Front speaker 13b Rear speaker 13l Left speaker 13r Right speaker 13t Ceiling speaker 14 Control part 14a Running condition acquisition part 14b Waveform adjustment part 14c Volume adjustment part 14d Sound image adjustment unit 14e Output control unit 15 Storage unit 15a Sound source information 20 Sound wave 50 Vehicle 50e Engine room 50e-t Engine room top 50t Trunk room 50t-t Trunk room top 100 Headlight light 200 Sound image 200f Front sound image 200b Rear sound image 300 Pedestrian W Bulkhead

Claims (7)

A simulated vehicle sound generating device that generates simulated vehicle sound that simulates vehicle sound,
A pseudo vehicle sound generating device provided with an output means provided in a closed space or a semi-closed space including a surface in contact with the outside of a structure constituting a vehicle, and outputting the pseudo vehicle sound . The output means includes
The pseudo vehicle sound generation device according to claim 1, wherein the pseudo vehicle sound generation device is provided in a front region and a rear region of the vehicle. The output means includes
The pseudo vehicle sound generation device according to claim 1, wherein the pseudo vehicle sound generation device is provided in each side region of the vehicle. The sound image adjusting means for adjusting so that one or a plurality of sound images are localized by the pseudo vehicle sound respectively output from a plurality of the output means. Simulated vehicle sound generator. A traveling direction acquisition means for acquiring a traveling direction of the vehicle;
The sound image adjusting means is
The pseudo vehicle sound generation device according to claim 4, wherein the position of the sound image is changed based on the traveling direction acquired by the traveling direction acquisition unit. Storage means for storing predetermined sound source information;
Waveform adjustment means for generating the pseudo vehicle sound by adjusting the waveform of the sound source information read from the storage means,
The output means includes
The pseudo vehicle sound generation device according to claim 1, wherein the pseudo vehicle sound provided from the waveform adjusting unit is output. The output means includes
The pseudo vehicle sound generation device according to claim 1, wherein the pseudo vehicle sound generation device is arranged toward an upper direction of the vehicle.

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