Active running sound effect generator

Abstract

To allow a high frequency component signal generated from a vehicle front side to be associated with an intake sound, and to allow a low frequency component signal generated from a vehicle rear side to be associated with an exhaust sound.SOLUTION: An active travel effective sound generator 100 includes: a waveform generation section 10 for generating a signal according to vehicle information; a plurality of speakers 50 for outputting the signal generated by the waveform generation section 10; and a sound image control processing section 41 for changing a level of an output from each of the plurality of speakers 50 for the signal. The waveform generation section 10 generates a low frequency waveform signal which contains relatively many low frequency components, and a high frequency waveform signal which contains relatively more high frequency components than the low frequency waveform signal does. The sound image control processing section 41 outputs the low frequency waveform signal at a relatively low level and the high frequency components at a relatively high level from a speaker 51 arranged on a front side of a vehicle, and outputs the low frequency waveform signal at a relatively higher level and the high frequency components at a relatively lower level from a speaker 5S arranged on a rear side of the vehicle than from the speaker 51 arranged on the front side.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an active running sound effect generating device. [Background technology]

[0002] BACKGROUND ART Conventionally, active sound effect generating devices have been considered for generating sound effects according to changes in vehicle speed caused by the driver's operation of the accelerator pedal when driving a vehicle (for example, Patent Documents 1 and 2).

[0003] As a technology related to this active sound effect generating device, the abstract of Patent Document 1 describes an active sound effect generating device that is capable of at least one of generating more natural sound effects and being applicable to electric vehicles (see Patent Document 1).

[0004] In addition, the abstract of Patent Document 2 describes an active sound effect generating device that generates sound effects in response to an increase in vehicle speed, producing highly realistic sound effects as the sound of a car traveling even at high speeds (see Patent Document 2).

[0005] Furthermore, as a technology relating to an audio output control device in a vehicle, the abstract of Patent Document 3 describes an audio output control device that reproduces sound data from a DVD (Digital Versatile Disc) as Dolby Digital 5.1ch surround sound (see Patent Document 3). The audio output control device described in Patent Document 3 uses a surround speaker system to output 5.1ch surround sound signals from the front left and right, rear left and right, center, and subwoofer speakers of the vehicle. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-229403 [Patent Document 2] JP 2019-128378 A [Patent Document 3] Japanese Patent Application Laid-Open No. 2000-209699 Summary of the Invention [Problem to be solved by the invention]

[0007] In order to provide passengers with more realistic driving sound effects, it is desirable to control the sound images of sound effects generated depending on the driving state so that they are generated in appropriate locations. For example, it is desirable to control the sound image of a component simulating intake sound so that it is generated from the engine compartment at the front of the vehicle, while the sound image of a component simulating exhaust sound is generated from the muffler at the rear of the vehicle.

[0008] However, in the active sound effect generating devices described in Patent Documents 1 and 2, the driving sound effects are output evenly from each speaker, making it impossible to control the sound image. Also, in the audio output control device described in Patent Document 3, the 5.1ch surround sound signal is simply output directly from each speaker, and no consideration is given to control of the sound effects generated depending on the driving state to give the occupants a more realistic feeling.

[0009] The present invention has been made in consideration of the above circumstances, and has as its object to provide an active driving sound effect generator that can associate high-frequency component signals generated from the front of the vehicle with intake sounds, and low-frequency component signals generated from the rear of the vehicle with exhaust sounds, thereby providing occupants with a sense of realism as if they were riding in a vehicle equipped with an engine. [Means for solving the problem]

[0010] That is, in order to solve the above-mentioned problems of the present invention, an active driving sound effect generating device is an active driving sound effect generating device mounted on a vehicle, and comprises: a waveform generating unit that generates a signal in accordance with vehicle information; a plurality of speakers that output the signals generated by the waveform generating unit; and a sound image control unit that changes the output magnitude of each of the plurality of speakers for the signal, wherein the waveform generating unit generates a low-frequency waveform signal that contains relatively more low-frequency components, and a high-frequency signal that contains relatively more high-frequency components than the low-frequency waveform signal, and the sound image control unit outputs the low-frequency waveform signal relatively small and the high-frequency components relatively large from the speaker located at the front of the vehicle, and outputs the low-frequency waveform signal relatively large and the high-frequency components relatively small from the speaker located at the rear of the vehicle than from the speaker located at the front. [Effects of the Invention]

[0011] According to the present invention, high-frequency component signals generated from the front of the vehicle can be associated with intake sounds, and low-frequency component signals generated from the rear of the vehicle can be associated with exhaust sounds, providing occupants with a sense of realism as if they were riding in a vehicle equipped with an engine. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a block diagram showing a schematic configuration of an active driving sound effect generation device according to an embodiment of the present invention mounted on a vehicle. [Figure 2] FIG. 2 is a block diagram showing a schematic configuration of a waveform generating unit. [Figure 3A] FIG. 10 is an explanatory diagram (part 1) showing the concept of the generation processing unit reading out a signal (waveform data) at a position obtained by adding the acquired skip number to the previous read position. [Figure 3B] FIG. 10 is an explanatory diagram (part 2) showing the concept of the generation processing unit reading out a signal (waveform data) at a position obtained by adding the acquired skip number to the previous read position. [Figure 4] FIG. 10 is an explanatory diagram showing an example of a process for synthesizing waveform tables. [Figure 5] 10 is an explanatory diagram showing the characteristics of a gain adjustment unit of a gain control unit adding gain to a signal acquired from a waveform generation unit. FIG. [Figure 6] FIG. 2 is a block diagram showing the configuration of a sound image control processing unit. [Figure 7A] 1 shows a display audio system installed in a vehicle. [Figure 7B] This shows a low-frequency waveform table that is an example of the powerful EV sports sound. [Figure 7C] This shows a high-frequency table, an example of the futuristic EV sound. [Figure 8A] FIG. 10 is an explanatory diagram showing a configuration in which a button for adding a tone (waveform table) is provided on the tone screen of the display audio. [Figure 8B] FIG. 10 is an explanatory diagram showing a waveform table added to a waveform generating unit by a user. [Figure 9A] FIG. 10 is an explanatory diagram showing a first skip table. [Figure 9B] FIG. 10 is an explanatory diagram showing a second skip table. DETAILED DESCRIPTION OF THE INVENTION

[0013] The following describes in detail embodiments of the present invention. Note that the embodiments described below are examples for realizing the present invention, and should be appropriately modified or changed depending on the configuration of the device to which the present invention is applied and various conditions. The present invention is not limited to the following embodiments. In addition, in each drawing, the same components are given the same reference numerals, and their description will be omitted as appropriate.

[0014] <Present Embodiment> [Outline of the active running sound effect generator] FIG. 1 is a block diagram showing a schematic configuration of an active driving sound effect generation device according to this embodiment mounted on a vehicle (see FIG. 6).

[0015] As shown in FIG. 1, the active running sound effect generation device 100 according to this embodiment is configured to include a waveform generation unit 10, a gain coefficient calculation unit 20, a gain control unit 30, an audio control unit 40, and a speaker 50.

[0016] In this embodiment, the waveform generating unit 10, the gain coefficient calculating unit 20, the gain control unit 30, and the audio control unit 40 constitute an active sound control (ASC) device. Active sound control is a system that improves the quality of acceleration sounds heard inside the vehicle depending on the accelerator pedal position. That is, active sound control provides the user with acceleration sounds that correspond to the vehicle speed or the rotation speed by emitting sounds synchronized with the vehicle speed or the rotation speed from the speaker 50 inside the vehicle.

[0017] As shown in vehicle 300 in FIG. 6 described later, speaker 51 is arranged at the front of vehicle 300 (for example, in front of the driver's seat or passenger seat), speaker 52 is arranged approximately in the center of vehicle 300 (for example, to the side of the driver's seat or passenger seat), and speaker 5S is arranged at the rear of vehicle 300 (for example, behind the rear seat).

[0018] Vehicle 300 is configured as, for example, a fuel cell vehicle, an electric vehicle including a hybrid vehicle, or the like, and is configured with a motor (not shown). This motor is controlled by a motor ECU (Electronic Control Unit) (not shown).

[0019] The waveform generation unit 10 of the active driving sound effect generation device 100 generates signals from a waveform table in accordance with vehicle information. The waveform generation unit 10 is provided with a plurality of waveform tables, and generates signals from each of the plurality of waveform tables. Here, the vehicle information is the vehicle speed or the rotation speed of the power unit. Note that the power unit is not limited to a motor, and may be, for example, an engine.

[0020] The waveform generating unit 10 is configured to include a vehicle speed / rotation speed acquiring unit 11 and frequency component group generating processors 12-1, ..., 12-N. When it is not necessary to specify which of the frequency component group generating processors 12-1, ..., 12-N is used, it will be simply referred to as frequency component group generating processor 12.

[0021] The vehicle speed / rotation speed acquisition unit 11 acquires the vehicle speed or the rotation speed of the power unit as vehicle information from the vehicle 300 (see FIG. 6 ). The vehicle speed / rotation speed acquisition unit 11 is configured by, for example, a vehicle speed sensor. The vehicle speed / rotation speed acquisition unit 11 acquires the vehicle speed or the rotation speed of the power unit based on the rotation speed of the motor or the axle (not shown) using the vehicle speed sensor, and supplies it to the gain coefficient calculation unit 20.

[0022] Each of the frequency component group generation processors 12-1, ..., 12-N has a corresponding waveform table (tone). For example, the frequency component group generation processor 12-1 has a low-frequency waveform table that includes a relatively large number of low-frequency components, and the frequency component group generation processor 12-2 (when N is 2) has a high-frequency waveform table that includes a relatively large number of high-frequency components than the low-frequency waveform table. The low-frequency waveform table only needs to include more low-frequency components than high-frequency components, and may be composed of only low-frequency components. The high-frequency table only needs to include more high-frequency components than low-frequency components, and may be composed of only high-frequency components. The low-frequency waveform table and the high-frequency waveform table are not limited to waveform tables, and may be data including low-frequency waveform signals and high-frequency signals.

[0023] Each of the frequency component group generation processors 12-1, . . . , 12-N has a different waveform table, and thus the waveform generation section 10 has a plurality of waveform tables.

[0024] Fig. 2 is a block diagram showing a schematic configuration of the waveform generation unit. As shown in Fig. 2, the waveform generation unit 10 is configured to include a skip table 123 and a generation processing unit 124. The generation processing unit 124 has a waveform table 125 that forms a tone color, and the waveform table 125 is waveform data read by the generation processing unit 124 and is configured of table values. Note that the waveform table 125 is an example of waveform data that includes multiple frequency components (1 [Hz], 2 [Hz], 4 [Hz], etc.) with 1 [s] as one period.

[0025] The skip table 123 acquires the skip number of the read position based on the vehicle information. The skip table 123 is provided in the vehicle speed / rotation number acquisition unit 11, for example.

[0026] The skip table 123 includes at least one of a vehicle speed step table 121 and a rotation speed step table 122. In the vehicle speed step table 121, a skip number (read width) ΔP is defined based on the vehicle speed [km / h] of the vehicle 300. In addition, in the rotation speed step table 122, the skip number ΔP is defined based on the rotation speed [rpm] of the power unit. Note that the skip number indicates, for example, the read width for reading waveform data when reading the waveform table 125. In other words, the skip number indicates the ratio at which the waveform table 125 is thinned out, and is the speed-up value when the waveform table 125 is played back at double speed.

[0027] The skip number ΔP is stored in table format in the skip table 123. For example, based on the vehicle speed step table 121, the vehicle speed / revolution number obtaining unit 11 reads out the skip number ΔP as 1 when the vehicle speed is 10 [km / h], and reads out the skip number ΔP as 4 when the vehicle speed is 20 [km / h]. Furthermore, the vehicle speed / revolution number obtaining unit 11 reads out the skip number ΔP as 9 when the vehicle speed is 30 [km / h], and reads out the skip number ΔP as 400 when the vehicle speed is 200 [km / h].

[0028] Furthermore, for example, the vehicle speed / rotation speed acquisition unit 11 reads out the skip number ΔP as 1 when the rotation speed of the power unit is 600 [rpm], and reads out the skip number ΔP as 2 when the rotation speed of the power unit is 700 [rpm], based on the rotation speed step table 122. Furthermore, the vehicle speed / rotation speed acquisition unit 11 reads out the skip number ΔP as 4 when the rotation speed of the power unit is 800 [rpm], and reads out the skip number ΔP as 100 when the rotation speed of the power unit is 3000 [rpm].

[0029] In this way, when the vehicle speed or the rotation speed of the power unit is acquired by the vehicle speed / rotation speed acquisition unit 11, the waveform generation unit 10 acquires the skip number ΔP of the read position based on the vehicle speed or the rotation speed. Note that the skip number ΔP of the vehicle speed step table 121 or the rotation speed step table 122 is defined as the skip number desired by the user.

[0030] On the other hand, a generation processing unit 124 is provided for each of frequency component group generation processing units 12-1, ..., 12-N. That is, a generation processing unit 124 corresponds to each of frequency component group generation processing units 12-1, ..., 12-N. Based on the skip number ΔP acquired by vehicle speed / rotation speed acquisition unit 11, generation processing unit 124 reads out a signal at a position obtained by adding the acquired skip number ΔP to the previously read position of waveform table 125, thereby generating a signal to be input to speaker 50 (i.e., a waveform table of skip number ΔP).

[0031] Here, the signal generated by the generation processing unit 124 is defined by the following equation (1).

[0032]

number

[0033] As shown in equation (1), the signal input to speaker 50 is generated by vehicle speed / rotation speed acquisition unit 11 reading waveform table 125 for skip number ΔP at the previous value of pointer P(t) based on skip number ΔP read from skip table 123 and the previous value of pointer P(t). In this case, the waveform data in waveform table 125 for skip number ΔP becomes the signal (tone).

[0034] 3A and 3B are explanatory diagrams showing the concept of the generation processing unit reading out a signal (waveform data) at a position obtained by adding the acquired skip number to the previous read position.

[0035] 3A shows the concept of the generation processing unit 124 reading out signals (waveform data) from the waveform table 126 when, for example, the skip number ΔP is 2. As shown in FIG. 3A, the generation processing unit 124 reads out waveform data (waveform table 127) from the previous read position at twice the cycle (two round trips) of the waveform data (waveform table 126) for one cycle per second.

[0036] 3B shows the concept of generation processing unit 124 reading out signals from waveform table 128 when, for example, skip count ΔP is 3. As shown in FIG. 3B, generation processing unit 124 reads out waveform data (waveform table 129) from the previous read position at a cycle three times longer (three round trips) than the one cycle of waveform data (waveform table 128) per second.

[0037] Here, the waveform tables 126 and 128 hold the value of the signal (waveform data) for one period in a table format. In this embodiment, the waveform tables 126 and 128 from which the waveform generating section 10 reads waveform data are characterized.

[0038] Fig. 4 is an explanatory diagram showing an example of a process for synthesizing waveform tables. Fig. 4 shows a process for synthesizing waveform table 134 of waveform data having three frequency components from waveform table 131 with a frequency of 1 [Hz], waveform table 132 with a frequency of 1.25 [Hz], and waveform table 133 with a frequency of 1.5 [Hz].

[0039] The three waveform tables 131, 132, and 133 have different periods, and therefore cannot be synchronized in units of one second. Therefore, in this embodiment, to generate a waveform table 134 having three frequency components, the frequencies of the waveform tables 131, 132, and 133 are multiplied by an integer while maintaining their ratio, and the minimum time [s] (multiplier) at which synchronization can be achieved is determined from the integer value. By making the frequency ratio an integer, the waveform data of the waveform tables 131, 132, and 133 have the same value at their start and end points, allowing synchronization at each timing. Therefore, in this embodiment, the minimum time [s] at which synchronization can be achieved among the waveform tables 131, 132, and 133 is defined as one period, and the waveform data of each waveform table 131, 132, and 133 is synthesized to generate the waveform table 134 having three frequency components.

[0040] In this manner, in this embodiment, after the ratio of the frequencies in the waveform tables 131, 132, and 133 is made into an integer, the minimum required time (minimum time) of the data string of waveform data is determined.

[0041] In the example of Figure 4, the frequency ratio between waveform table 131 (1 Hz), waveform table 132 (1.25 Hz), and waveform table 133 (1.5 Hz) is 1:1.25:1.5. Integer multiplication of this frequency ratio results in 4:5:6 or 100:125:150. In this case, the minimum time (s) at which waveform tables 131, 132, and 133 can be synchronized is determined to be 4 s, since (1:1.25:1.5) x 4 is 4:5:6. Once the minimum time (4 s) is determined, the waveform data in waveform table 131 will be waveform data for four periods, the waveform data in waveform table 132 will be waveform data for five periods, and the waveform data in waveform table 133 will be waveform data for six periods.

[0042] Then, waveform table 134 generates waveform data with the minimum time [s] as one period by adding period data (4 periods, 5 periods, 6 periods) that is an integer multiple of each of waveform tables 131, 132, and 133 over the minimum time (4 [s]) that allows synchronization between waveform tables 131, 132, and 133. As a result, the generated waveform table 134 is a periodic waveform table in which the end and start points of the waveform data are consecutive, and is a table containing multiple frequency components.

[0043] In other words, in this embodiment, the waveform table 134 is formed from waveform data in which the period of the waveform table is the smallest multiplier (i.e., the smallest time) that makes all of the frequency ratios integers while maintaining the ratios of multiple frequencies.

[0044] In this way, the waveform table 134 containing a plurality of frequency components is generated from the waveform data of the waveform tables 131, 132, and 133 containing the frequency components desired by the user.

[0045] Returning to FIG. 1, the gain coefficient calculation unit 20 of the active driving sound effect generation device 100 is configured to include an accelerator opening sensor 21, an acceleration calculation unit 22, a rotation speed change amount calculation unit 23, a vehicle speed / rotation speed gain table 24, an accelerator gain table 25, an acceleration gain table 26, and a rotation speed change gain table 27.

[0046] The accelerator opening sensor 21 detects the opening of the accelerator pedal when the user depresses the accelerator pedal of the vehicle 300 (this is referred to as accelerator opening θ).

[0047] The acceleration calculation unit 22 acquires the vehicle speed or the rotation speed of the power unit from the vehicle speed / rotation speed acquisition unit 11, and calculates the acceleration Δa.

[0048] The rotation speed change amount calculation unit 23 acquires the vehicle speed or the rotation speed of the power unit from the vehicle speed / rotation speed acquisition unit 11, and calculates the rotation speed change amount Δb.

[0049] The vehicle speed / rpm gain table 24 has a characteristic of adding a gain to the supplied vehicle speed or power unit rpm. The accelerator gain table 25 has a characteristic of adding a gain to the detected accelerator opening θ. The acceleration gain table 26 has a characteristic of adding a gain to the calculated acceleration Δa. The rpm change gain table 27 has a characteristic of adding a gain to the calculated rpm change amount Δb.

[0050] The vehicle speed / revolution gain table 24, accelerator gain table 25, acceleration gain table 26, and revolution speed change gain table 27 are set in table format as appropriate to the predetermined characteristics desired by the user.

[0051] The gain control unit 30 of the active running sound effect generation device 100 is configured to include a plurality of gain adjustment units 31, ... 3N. The gain control unit 30 obtains from the waveform generation unit 10 the signals u1, ... uN generated by each frequency component group generation processing unit 12-1, ... 12-N, and obtains from the gain coefficient calculation unit 20 a coefficient for adjusting the gain of each signal u1, ... uN.

[0052] Each of the multiple gain adjustment units 31,...3N corresponds to a respective signal u1,...uN generated from the waveform table of the frequency component group generation processing units 12-1,...12-N. Thus, each gain adjustment unit 31,...3N adjusts the gain of each corresponding signal u1,...uN generated by the frequency component group generation processing units 12-1,...12-N using the gain coefficient obtained from the gain coefficient calculation unit 20.

[0053] FIG. 5 is an explanatory diagram showing the characteristics of the gain adjustment unit of the gain control unit adding gain to the signal acquired from the waveform generation unit.

[0054] 5, when the vehicle speed or rotation speed is relatively low, the gain control unit 30 increases (raises) the gain of the low-frequency waveform table by a gain G1 indicating a low-frequency component. On the other hand, when the vehicle speed or rotation speed is relatively high, the gain control unit 30 increases (raises) the gain of the high-frequency waveform table by a gain G2 indicating a high-frequency component.

[0055] In FIG. 5, gain G1 indicates the gain characteristics of low frequency components (low frequency waveform signals), and gain G2 indicates the gain characteristics of high frequency components (high frequency waveform signals).

[0056] For example, if the frequency component group generation processing unit 12-1 has a low-frequency waveform table and the frequency component group generation processing unit 12-2 (when N is 2) has a high-frequency waveform table, the gain adjustment unit 31 uses gain G1 to emphasize and output the low-frequency components of the low-frequency waveform table of the frequency component group generation processing unit 12-1 when the vehicle speed or rotation speed is relatively low.

[0057] On the other hand, when the vehicle speed or rotation speed is relatively high, the gain adjuster 32 (when N is 2) emphasizes and outputs the high frequency components of the high frequency table of the frequency component group generator 12-2 using the gain G2.

[0058] The acoustic control unit 40 (see FIG. 1) of the active running sound effect generation device 100 is configured to include a sound image control processing unit 41. The sound image control processing unit 41 changes (adjusts) the magnitude of the output of each of the plurality of speakers 50 (51, 52, ... 5S) for each of the plurality of signal components y1, ... yN.

[0059] The sound image control processing unit 41 inputs a signal to each speaker 50, and the output sound output from each speaker 50 is expressed by the following equation (2).

[0060]

number

[0061] As shown in equation (2), the sound image control processing unit 41 adjusts the magnitude and delay time of the signals u1, ... uN generated by each frequency component group generation processing unit 12-1, ... 12-N by multiplying them by the gain coefficient set for each speaker 50. As a result, the output sound of each speaker 51, 52, ... 5S becomes the sum (result) of the frequency components whose magnitudes have been adjusted.

[0062] As a result, the sound image control processing unit 41 outputs a low-frequency waveform signal (low-frequency waveform component) at a relatively low level and a high-frequency component at a relatively high level from the speaker 51 located at the front of the vehicle 300, and outputs a low-frequency waveform signal (low-frequency waveform component) at a relatively high level and a high-frequency component at a relatively low level from the speaker 5S located at the rear of the vehicle 300 compared to the speakers 51, 52 located at the front.

[0063] Furthermore, the sound image control processing unit 41 can adjust the phase of the signal for each of the plurality of signal components y1,...,yN for each speaker 50. Therefore, the speaker 51 arranged at the front of the vehicle 300 can output a high-frequency waveform signal earlier and a low-frequency waveform signal later than the speaker 5S arranged at the rear of the vehicle 300.

[0064] Fig. 6 is a block diagram showing the configuration of a sound image control processing unit. As shown in Fig. 6, sound image control processing unit 41 includes amplifiers 421, 422,... 42S, 441, 442,... 44S that multiply each of a plurality of signal components y1,... yN by a constant for each speaker 51, 52,... 5S.

[0065] 6, when speakers 51, 52, ..., 5S are arranged, the sound image control processing unit 41 sets, for example, a coefficient of 1.0 for amplifier 421, a coefficient of 0.5 for amplifier 422, and a coefficient of 0.0 for amplifier 42S for signal component y1 of frequency component group generation processing unit 12-1, which assumes intake sound. As a result, the sound image control processing unit 41 localizes the sound image of signal component y1 in the front of the vehicle cabin.

[0066] On the other hand, for the signal component yN of the frequency component group generation processing unit 12-N that assumes the exhaust noise, the sound image control processing unit 41 sets, for example, a coefficient of 0.0 for the amplifier 441, a coefficient of 0.5 for the amplifier 442, and a coefficient of 1.0 for the amplifier 44S. As a result, the sound image control processing unit 41 localizes the sound image of the signal component yN at the rear of the vehicle interior.

[0067] In this way, speaker 51 outputs high frequency components relatively louder than speakers 52 and 5S, and speaker 52 outputs high frequency components relatively louder than speaker 5S. On the other hand, speaker 5S outputs low frequency components relatively louder than speakers 51 and 52, and speaker 52 outputs low frequency components relatively louder than speaker 51. Note that sound image control processing unit 41 may divide multiple speakers 50 (51, 52, ... 5S) into those for the front and rear of the vehicle cabin and control them collectively.

[0068] The sound image control processing unit 41 also includes delay adjustment elements 431, 432, ··· 43S, 451, 452, ··· 45S that adjust the phase of the signal for each of the speakers 51, 52, ··· 5S for each of the plurality of signal components y1, ··· yN.

[0069] Delay adjustment elements 431, 432,... 43S, 451, 452,... 45S set delay times by digital values ​​for each of signal components y1,... yN. This enables speaker 51 located at the front of vehicle 300 to output high-frequency components earlier and low-frequency waveform signals (low-frequency waveform components) later than speakers 52,... 5S located at the rear of vehicle 300.

[0070] As a result, speaker 51 adds, in adder 461, a signal amplified by amplifier 421 and delayed by delay adjustment element 431 and a signal amplified by amplifier 441 and delayed by delay adjustment element 451, and outputs the resulting sum signal s1 into the vehicle cabin. Speaker 52 adds, in adder 462, a signal amplified by amplifier 422 and delayed by delay adjustment element 432 and a signal amplified by amplifier 442 and delayed by delay adjustment element 452, and outputs the resulting sum signal s2 into the vehicle cabin. Speaker 5S can add, in adder 46S, a signal amplified by amplifier 42S and delayed by delay adjustment element 43S and a signal amplified by amplifier 44S and delayed by delay adjustment element 45S, and output the resulting sum signal sS into the vehicle cabin.

[0071] [Active running sound effect generator in operation] <Operation 1> Next, the operation of the active running sound effect generation device 100 according to the first embodiment will be described with reference to FIG. 1 and FIGS. 7A to 9B.

[0072] The active running sound effect generation device 100 acquires the vehicle speed or the rotation speed of the power unit as vehicle information of the vehicle 300 by the vehicle speed / rotation speed acquisition unit 11. The vehicle speed / rotation speed acquisition unit 11 acquires the skip number ΔP based on the acquired vehicle speed or the rotation speed of the power unit.

[0073] The frequency component group generators 12-1, . . . , 12-N (generator 124) read out the signal at the position obtained by adding a skip number ΔP to the read position P(t) of each waveform table, and input the signal to the gain controller 30.

[0074] The gain coefficient calculation unit 20 calculates a gain coefficient for each of the signals u1, . . . uN from a vehicle speed / rotation speed gain table 24, an accelerator gain table 25, an acceleration gain table 26, and an acceleration gain table 26 based on the accelerator opening θ of the accelerator opening sensor 21 and the vehicle speed or the rotation speed of the power unit acquired by the vehicle speed / rotation speed acquisition unit 11.

[0075] The gain control unit 30 controls (adjusts) the gains corresponding to the signals u1, ..., uN generated from the plurality of waveform tables of the frequency component group generation processing units 12-1, ..., 12-N, using the gain coefficients calculated by the gain coefficient calculation unit 20.

[0076] The acoustic control unit 40 changes the magnitude of the output for each of the multiple speakers 50 for each signal component y1, ..., yN and inputs it to each speaker 50. This allows each speaker 50 to output the signals u1, ..., uN generated by the waveform generation unit 10.

[0077] <Operation 2> In this embodiment, the active running sound effect generator 100 has a waveform table for each of the frequency component group generation processing units 12-1, ..., 12-N in the waveform generation unit 10, and is therefore provided with a plurality of waveform tables. Therefore, the waveform generation unit 10 can accept a user operation and switch the waveform table from among the plurality of waveform tables in response to the user's operation.

[0078] 7A to 7C are explanatory diagrams showing that a desired waveform table can be selected from a plurality of waveform tables provided in the frequency component group generation processing unit of the waveform generating unit.

[0079] 7A shows a display audio provided in a vehicle 300. As shown in FIG. 7A, the display audio 200 is provided with a volume screen 201 and a tone screen 202.

[0080] The volume screen 201 allows the user to turn volume customization ON / OFF, and when it is ON, the volume can be adjusted.

[0081] The tone screen 202 allows the user to switch between tones using a button in response to a selection operation. For example, the tone screen 202 allows the user to select between a powerful EV (Electric Vehicle) sports tone and a futuristic EV tone. In this case, when the user selects the powerful EV sports tone, the waveform table 1201 shown in FIG. 7B is selected from the frequency component group generation processing units 12-1, ..., 12-N of the waveform generation unit 10. On the other hand, when the user selects the futuristic EV tone, the waveform table 1202 shown in FIG. 7C is selected from the frequency component group generation processing units 12-1, ..., 12-N of the waveform generation unit 10.

[0082] Waveform table 1201 in FIG. 7B shows a low-frequency waveform table that is an example of a powerful EV sports tone, and waveform table 1202 in FIG. 7C shows a high-frequency waveform table that is an example of a futuristic EV tone.

[0083] For example, waveform table 1201 corresponds to frequency component group generation processing unit 12-1, and waveform table 1202 corresponds to frequency component group generation processing unit 12-2, allowing the user to select a waveform table that outputs a preferred tone.

[0084] Furthermore, a waveform table that outputs a desired tone color may be added separately by the user. For example, the tone color screen 202 may be configured to include a button 203 that allows the user to add a tone color.

[0085] <Operation 3> Fig. 8A is an explanatory diagram showing a configuration in which a button for adding a tone (waveform table) is provided on the tone screen of the display audio. Fig. 8B is an explanatory diagram showing a waveform table added by a user to the waveform generation unit. Waveform table 1203 is waveform data downloaded from the Internet by the user as tone data. Like waveform table 134, waveform table 1203 is a periodic waveform table in which the end point and start point of the waveform table are consecutive, and includes multiple frequency components.

[0086] 8A, the user can add a desired waveform table to the waveform generating section 10 by pressing button 203. This allows the waveform generating section 10 to add waveform table 1203 to multiple waveform tables (frequency component group generation processing sections 12-1, ..., 12-N).

[0087] The waveform generating section 10 can be configured to be able to switch the waveform table that generates the signal to be input to the speaker 50 from among the multiple waveform tables to the added waveform table 1203. In this case, the user can add the waveform table 1203 from the Internet or an external memory, for example, and can select to output the signal of the added waveform table 1203.

[0088] In this way, the waveform generating section 10 can accept addition of the waveform table 1203 and can also accept selection of waveform data (tone) of the waveform table 1203 to be output by the speaker 50.

[0089] <Operation 4> The waveform generating unit 10 also includes a vehicle speed / rotation speed acquiring unit 11, which includes a skip table 123.

[0090] The skip table 123 may include, for example, a vehicle speed step table 121 and a rotation speed step table 122. Therefore, the skip table 123 can be switched by selecting either the vehicle speed step table 121 or the rotation speed step table 122 through a user selection operation.

[0091] 9A is an explanatory diagram showing the first skip table 1231. As shown in FIG. 9A, the first skip table 1231 exponentially increases the skip number from a lower limit value to an upper limit value based on an increase in vehicle speed or power unit rotation speed, and returns to the lower limit value when the upper limit value is reached. In the first skip table 1231, the skip number is returned to the lower limit value, and then exponentially increased again. This allows the first skip table 1231 to generate an infinite scale signal.

[0092] 9B is an explanatory diagram showing the second skip table 1232. As shown in FIG. 9B, the second skip table 1232 increases the frequency in proportion to an increase in vehicle speed or power unit rotation speed, and decreases the frequency by a predetermined amount when the vehicle speed or power unit rotation speed reaches a predetermined value. After decreasing the frequency, the second skip table 1232 increases the frequency again in proportion to an increase in vehicle speed or power unit rotation speed, increasing it in a stepped manner. This allows the second skip table 1232 to generate an engine wind signal.

[0093] For example, when a futuristic EV tone is selected by a user's selection operation on tone screen 202 of Fig. 7A or 8A, first skip table 1231 of Fig. 9A is selected. On the other hand, when an engine-like tone is selected by a user's selection operation on tone screen 202, second skip table 1232 of Fig. 9B is selected.

[0094] As a result, when the first skip table 1231 is selected, the waveform generation unit 10 is able to generate a futuristic EV signal (infinite scale signal) in the vehicle speed / rotation speed acquisition unit 11. On the other hand, when the second skip table 1232 is selected, the waveform generation unit 10 is able to generate an engine wind signal in the vehicle speed / rotation speed acquisition unit 11.

[0095] In particular, when the first skip table 1231 (infinite scale signal) is selected, the waveform generating unit 10 can output an engine-like tone, but can output an infinite scale signal by outputting the low-frequency waveform signal and the high-frequency waveform signal directly from the speakers 51, 52, ... 5S without deliberately controlling them according to the position of the speaker 50.

[0096] As described above, the active running sound effect generation device 100 according to this embodiment is configured to include the waveform generation section 10, the speaker 50, and the sound image control processing section 41.

[0097] According to this embodiment, the waveform generating unit 10 generates a low-frequency waveform signal that contains a relatively large number of low-frequency components, and a high-frequency signal that contains a relatively large number of high-frequency components compared to the low-frequency waveform signal. The sound image control processing unit 41 outputs a low-frequency waveform signal (low-frequency components) that is relatively small and a high-frequency component (high-frequency signal) that is relatively large from the speaker 51 located at the front of the vehicle 300, and outputs a low-frequency waveform signal (low-frequency components) that is relatively large and a high-frequency component (high-frequency signal) that is relatively small from the speaker 51 located at the front of the vehicle.

[0098] With this configuration, the active driving sound effect generation device 100 can associate a signal of high frequency components generated from the front side of the vehicle with intake noise by outputting a relatively small low-frequency waveform signal (low-frequency components) and a relatively large high-frequency component (high-frequency signal) from the speaker 51 using the sound image control processing unit 41. Also, by outputting a relatively large low-frequency waveform signal (low-frequency components) and a relatively small high-frequency component (high-frequency signal) from the speaker 5S compared to the speaker 51 disposed in front, it can associate a signal of low frequency components generated from the rear side of the vehicle with exhaust noise.

[0099] As a result, the active driving sound effect generation device 100 can provide the passengers of the vehicle 300 with a sense of realism as if they were riding in a vehicle equipped with an engine.

[0100] 6, the sound image control processing unit 41 can adjust the phase of the signal for each speaker 50 for each of the multiple signal components y1,...,yN. Thus, the speaker 51 located at the front of the vehicle 300 outputs a high-frequency signal earlier and a low-frequency signal later to the speaker 5S located at the rear of the vehicle 300. Adjusting the phase of the signal means setting a delay time for the signal as a digital value.

[0101] With this configuration, the active running sound effect generator 100 allows high frequency components (high frequency signals) to arrive earlier at the front of the vehicle than at the rear, while allowing low frequency components (low frequency waveform signals) to arrive later.

[0102] As a result, the active driving sound effect generation device 100 can give the occupants of the vehicle 300 a sense of realism that is closer to that of a vehicle equipped with an actual engine.

[0103] In particular, the sound image control processing unit 41 can precisely adjust the delay with digital values ​​using the delay adjustment elements 431, 432,... 43S, 451, 452,... 45S according to the positions of the occupants of the vehicle 300. This allows the active driving sound effect generation device 100 to provide a sense of realism close to that of a real engine sound, regardless of where the occupants are sitting in the vehicle 300.

[0104] Furthermore, as explained in operation 2 using Figures 7A to 7C, the active driving sound effect generator 100 may be configured such that the vehicle information is the vehicle speed or the rotation speed of the power unit, and the waveform generating unit 10 increases the frequency in proportion to an increase in the vehicle speed or the rotation speed, and decreases the frequency by a predetermined number when the vehicle speed or the rotation speed reaches a predetermined value.

[0105] With this configuration, the active driving sound effect generator 100 can output an engine wind signal from the speaker 50 by increasing or decreasing the frequency with the waveform generator 10, and can provide the occupants of the vehicle 300 with a sense of realism closer to that of a vehicle equipped with an engine. Specifically, the active driving sound effect generator 100 can generate a sound that sounds like a gear being shifted up with the waveform generator 10.

[0106] 9A and 9B in operation 4, the waveform generation unit 10 can generate an infinite scale signal that exponentially increases the frequency from a lower limit value to an upper limit value based on an increase in vehicle speed or rotation speed, and returns to the lower limit value when the upper limit value is reached, and then exponentially increases again, and the generation of an engine wind signal and an infinite scale signal may be selected. In this embodiment, when the generation of an infinite scale signal is selected, the sound image control processing unit 41 outputs each signal component y1,...,yN directly from the front and rear speakers 50 without controlling the low-frequency waveform signal and the high-frequency waveform signal according to the position of the speakers 50.

[0107] With this configuration, the active running sound effect generator 100 can also generate an infinite scale signal by the waveform generator 10, making it possible to select between generating an engine wind signal and an infinite scale signal. When generation of an infinite scale signal is selected, the active running sound effect generator 100 outputs the sound image signal as is from the front and rear speakers 50 without dividing it into low-frequency signals and high-frequency signals by the sound image control processor 41, and without controlling the low-frequency signals and high-frequency signals according to the positions of the speakers 50.

[0108] This allows the active driving sound effect generating device 100 to easily output infinite scale signals using the waveform generating unit 10, thereby giving the occupants of the vehicle 300 a sense of realism (e.g., a sense of acceleration) different from that of an engine-equipped vehicle.

[0109] 6, the sound image control processing unit 41 is configured to include amplifiers 421, 422,... 42S, 441, 442,... 44S that multiply each of the plurality of signal components y1,... yN by a constant for each speaker 50. The constants include 0.

[0110] With this configuration, the active running sound effect generation device 100 can easily multiply the signals u1, uN (or signal components y1, yN) generated by the generation processing unit 124 by a constant using the multiple amplifiers 421, 422, . . . 42S, 441, 442, . . . 44S. This allows the active running sound effect generation device 100 to easily control the output of each of the speakers 51, 52, . . . 5S of the vehicle 300 using the multiple amplifiers 421, 422, . . . 42S, 441, 442, . . . 44S. [Explanation of symbols]

[0111] 10 Waveform generator 11 Vehicle speed / rotation speed acquisition unit 12, 12-1, 12-2, 12-N Frequency component group generation processing unit 20 Gain coefficient calculation section 21 Accelerator opening sensor 22 Acceleration calculation unit 23 Rotation speed change calculation unit 24 Vehicle speed / rpm gain table 25 Acceleration Gain Table 26 Acceleration Gain Table 27 RPM Change Gain Table 30 Gain control section 31 Gain adjustment section 40 Sound control section 41 Sound image control processing section 121 Vehicle speed step table 122 Rotational Speed ​​Step Table 123 Skip Table 124 Generation processing unit 125,127,129,134 Wavetable 1201,1202,1203 Waveform Table 1231 First Skip Table 1232 Second Skip Table 300 vehicles

Claims

1. An active driving sound effect generating device mounted on a vehicle, a waveform generating unit that generates a signal in accordance with vehicle information; a plurality of speakers that output the signals generated by the waveform generation unit; a sound image control unit that changes the magnitude of an output for each of the plurality of speakers in response to the signal, The waveform generating unit generating a low-frequency waveform signal containing a relatively large amount of low-frequency components and a high-frequency waveform signal containing a relatively large amount of high-frequency components compared to the low-frequency waveform signal; The sound image control unit The low-frequency waveform signal is outputted relatively at a low volume and the high-frequency component is outputted relatively at a high volume from the speaker disposed at the front of the vehicle; The speaker disposed at the rear of the vehicle outputs the low-frequency waveform signal at a relatively louder level and the high-frequency component at a relatively lower level than the speaker disposed at the front of the vehicle, The phase of the signal for each speaker can be adjusted for each of the plurality of signals; The speaker disposed at the front of the vehicle outputting the high-frequency waveform signal early and the low-frequency waveform signal late to the speaker disposed at the rear of the vehicle; Active running sound effect generator.

2. An active driving sound effect generating device mounted on a vehicle, a waveform generating unit that generates a signal in accordance with vehicle information; a plurality of speakers that output the signals generated by the waveform generation unit; a sound image control unit that changes the magnitude of an output for each of the plurality of speakers in response to the signal, The waveform generating unit generating a low-frequency waveform signal containing a relatively large amount of low-frequency components and a high-frequency waveform signal containing a relatively large amount of high-frequency components compared to the low-frequency waveform signal; The sound image control unit The low-frequency waveform signal is outputted relatively at a low volume and the high-frequency component is outputted relatively at a high volume from the speaker disposed at the front of the vehicle; The speaker disposed at the rear of the vehicle outputs the low-frequency waveform signal at a relatively louder level and the high-frequency component at a relatively lower level than the speaker disposed at the front of the vehicle, The vehicle information includes: Vehicle speed or power unit rotation speed, The waveform generating unit An engine wind signal can be generated that increases in frequency in proportion to an increase in the vehicle speed or the number of revolutions, and decreases in frequency by a predetermined number when the vehicle speed or the number of revolutions reaches a predetermined value. Active running sound effect generator.

3. The waveform generating unit An infinite scale signal can be generated in which the frequency increases exponentially from a lower limit value to an upper limit value based on an increase in the vehicle speed or the number of rotations, and when the upper limit value is reached, the frequency returns to the lower limit value and then increases exponentially again; Selectable generation of the engine wind signal and the infinite scale signal; The sound image control unit When the generation of the infinite scale signal is selected, the low frequency waveform signal and the high frequency waveform signal are outputted directly from the front and rear speakers without being controlled according to the positions of the speakers.

3. The active running sound effect generating device according to claim 2.

4. The sound image control unit an amplifier for multiplying each of the plurality of signals by a constant for each speaker; 3. The active running sound effect generating device according to claim 1 or 2.

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