Active driving sound effect generating device

Abstract

The invention provides an active driving sound effect generating device which can reduce the calculation amount in the process of generating a sound signal, can easily adjust the tone, and can generate a driving sound effect with high reality. An active travel sound effect generation device (100) is mounted on a vehicle (300) and comprises: a waveform generation unit (10) that generates a signal from a waveform table on the basis of vehicle information; and a speaker (30) that outputs the signal generated by the waveform generation unit (10), the waveform table being a periodic waveform table in which an end point and a start point of the waveform table are continuous, and including a plurality of frequency components.

Description

Technical Field

[0001] The invention relates to an active driving sound effect generating device. Background Art

[0002] Conventionally, active sound effect generating devices have been studied for vehicle driving operations, which generate sound effects corresponding to changes in vehicle speed associated with a driver's accelerator pedal operation (for example, Patent Documents 1 and 2).

[0003] As a technology related to the active sound effect generator, the abstract of Patent Document 1 describes an active sound effect generator that can achieve at least one of the generation of more natural sound effects and application to electric vehicles (see Patent Document 1).

[0004] Furthermore, the abstract of Patent Document 2 describes an active sound effect generator that generates a sound effect in response to an increase in vehicle speed, which is highly realistic as a driving sound of a car even in a high-speed area (see Patent Document 2).

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 2015-229403

[0008] Patent Document 2: Japanese Patent Application Publication No. 2019-128378 Summary of the Invention

[0009] The active sound effect generating devices described in Patent Documents 1 and 2 require a large amount of calculations. Therefore, the processing load is heavy, making it difficult to provide running sound effects in real time.

[0010] For example, the active sound effect generator described in Patent Document 1 includes a reference signal generating mechanism and a control signal generating mechanism. The reference signal generating mechanism generates a reference signal by sequentially reading waveform data from a waveform data table. Furthermore, the control signal generating mechanism generates a control signal for generating the sound effect based on the generated reference signal. The control signal generating mechanism adjusts the amplitude of the control signal by varying the amplitude of the reference signal according to the frequency change and the load of the driving source.

[0011] In addition, the active sound effect generating device described in Patent Document 1 also requires a rotation frequency variation calculation mechanism for calculating the time differential value of the rotation frequency, i.e., the rotation frequency variation, and an engine load detection mechanism for detecting the load of the engine. The amount of calculation required to adjust the amplitude of the control signal is large.

[0012] The active sound effect generator described in Patent Document 2 includes a waveform data table and an amplitude data table. The waveform data table generates a harmonic sound signal having a harmonic sound frequency from a 1 Hz sine wave. For example, the harmonic sound frequency may be three. In this case, the waveform data table generates three harmonic sound signals. Furthermore, the amplitude data table adjusts the amplitudes of the three harmonic sound signals. An adder combines (adds) the three harmonic sound signals after adjusting their amplitudes to generate a sound signal.

[0013] As such, the active sound effect generator described in Patent Document 2 still requires a large amount of computation to calculate harmonic sound signals, resulting in a heavy processing burden. Furthermore, the computation of harmonic sound signals further increases when simultaneously outputting multiple tones (groups of harmonic sound signals) or adjusting the volume.

[0014] Furthermore, when a user wants to individually adjust the waveform (timbre) of a sound effect, it is difficult for a general user to understand the setting of the harmonic wave, and thus adjustment of the timbre is difficult.

[0015] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an active running sound generator that can reduce the amount of calculation in the process of generating an acoustic signal, facilitate timbre adjustment, and generate a highly realistic running sound effect.

[0016] That is to say, in order to solve the above-mentioned problems of the present invention, the active running sound generating device is an active running sound generating device mounted on a vehicle, and is characterized in that it has: a waveform generating unit that generates a signal from a waveform table according to vehicle information; and a speaker that outputs the signal generated by the waveform generating unit, and the waveform table is a periodic waveform table with continuous end points and starting points of the waveform table, and contains multiple frequency components.

[0017] Effects of the Invention

[0018] According to the present invention, the amount of calculation in the process of generating an acoustic signal can be reduced, the timbre can be easily adjusted, and a highly realistic running sound effect can be produced. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a block diagram showing a schematic configuration of a vehicle equipped with the active running sound generating device according to the first embodiment.

[0020] Figure 2 This is a block diagram showing the schematic configuration of a waveform generating unit.

[0021] Figure 3A This is an explanatory diagram (part 1) showing the concept of a signal (waveform data) read by a generation processing unit at a position obtained by adding an acquired skip number to the previous reading position.

[0022] Figure 3B This is an explanatory diagram (part 2) showing the concept of a generation processing unit reading a signal (waveform data) at a position obtained by adding the acquired skip number to the previous reading position.

[0023] Figure 4 This is an explanatory diagram showing an example of processing for waveform table synthesis.

[0024] Figure 5 This is an explanatory diagram showing characteristics of gain applied by the gain adjustment section of the gain control section to the signal acquired from the waveform generation section.

[0025] Figure 6 This is a block diagram showing the configuration of an audio and video control processing unit.

[0026] Figure 7A Indicates the display speaker installed in the vehicle.

[0027] Figure 7B This table shows a low-frequency waveform as an example of the timbre of a powerful EV sport.

[0028] Figure 7C This table shows a high-frequency waveform as an example of the timbre of the futuristic EV.

[0029] Figure 8A This is an explanatory diagram showing the configuration of a button for adding a tone (wave table) on the tone screen of the display sound.

[0030] Figure 8B This is an explanatory diagram showing a waveform table added to the waveform generating unit by the user.

[0031] Figure 9A This is an explanatory diagram showing the first skip table.

[0032] Figure 9B This is an explanatory diagram showing the second skip table.

[0033] Figure 10 This is a block diagram showing a schematic configuration of a vehicle equipped with an active running sound generating device according to a second embodiment.

[0034] Figure 11A Indicates the coefficients of the bandpass filter included in the frequency characteristic adjustment processing unit.

[0035] Figure 11B It is an explanatory diagram showing the frequency characteristics based on the filter coefficients.

[0036] Figure 12A It is an explanatory diagram showing signals input to the frequency characteristic adjustment processing unit.

[0037] Figure 12BIt is an explanatory diagram showing a signal output from the frequency characteristic adjustment processing unit.

[0038] Figure 13 This is an explanatory diagram showing a configuration for switching filter coefficients of the active running sound generating device according to the second embodiment.

[0039] Figure 14 This is an explanatory diagram showing a comparative example of generating a waveform table including a plurality of frequency components.

[0040] Description of Reference Numerals

[0041] 10Waveform generation unit

[0042] 11 Vehicle speed / rotation speed acquisition unit

[0043] 12, 12-1, 12-2, 12-N frequency component group generation processing unit

[0044] 13. 13-1, 13-N frequency characteristic adjustment processing unit

[0045] 20 Gain coefficient calculation unit

[0046] 21 Accelerator opening sensor

[0047] 22 Acceleration calculation unit

[0048] 23 Speed change calculation unit

[0049] 24 vehicle speed / speed gain table

[0050] 25 Accelerator Gain Table

[0051] 26 Acceleration gain table

[0052] 27 Speed change gain table

[0053] 30 gain control unit

[0054] 31 gain adjustment unit

[0055] 40 Sound Control Department

[0056] 41 Audio and video control processing unit

[0057] 121 Speed ​​Step Table

[0058] 122 Speed step table

[0059] 123 Skip Table

[0060] 124 Generation Processing Unit

[0061] 125, 127, 129, 134 Waveform Tables

[0062] 1201, 1202, 1203 waveform tables

[0063] 1231 Skip Table 1

[0064] 1232 Second Skip Table

[0065] 131, 132, 133 Waveform Tables

[0066] 161, 162, 163 Waveform Tables

[0067] 300 vehicles DETAILED DESCRIPTION

[0068] The following describes in detail the methods for implementing the present invention. The embodiments described below are merely examples for implementing the present invention and can be modified or altered as appropriate 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 the figures, identical components are denoted by the same reference numerals, and description thereof is omitted as appropriate.

[0069] <First embodiment>

[0070] [General Structure of Active Driving Sound Generator]

[0071] Figure 1 Is to indicate that in the vehicle ( Figure 6 Reference) is a block diagram showing a schematic configuration of an active running sound generating device according to the first embodiment.

[0072] like Figure 1 As shown, the active running sound effect generating device 100 of this embodiment includes a waveform generating unit 10 , a gain coefficient calculating unit 20 , a gain control unit 30 , an acoustic control unit 40 , and a speaker 50 .

[0073] In this embodiment, the waveform generation unit 10, the gain coefficient calculation 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 sound quality of the acceleration sound heard inside the vehicle according to the accelerator pedal position. Specifically, active sound control provides the user with an acceleration sound that corresponds to the vehicle speed or power unit rotational speed by emitting a sound synchronized with the vehicle speed or power unit rotational speed from the speaker 50 into the vehicle interior.

[0074] about Figure 1 The speaker 50 shown, as described later Figure 6 As shown in the vehicle 300, the speaker 51 is arranged on the front side of the vehicle 300 (for example, in front of the driver's seat and the front passenger seat), the speaker 52 is arranged at the approximate center of the vehicle 300 (for example, beside the driver's seat and the front passenger seat), and the speaker 5S is arranged on the rear side of the vehicle 300 (for example, behind the rear seat).

[0075] The vehicle 300 is constituted by an electric vehicle such as a fuel cell vehicle or a hybrid vehicle, and includes a motor (not shown) controlled by a motor ECU (Electronic Control Unit) (not shown).

[0076] The waveform generator 10 of the active driving sound effect generator 100 generates a signal from a waveform table based on vehicle information. The waveform generator 10 includes multiple waveform tables and generates signals from each of these tables. Vehicle information refers to vehicle speed or the rotational speed of the power unit. The power unit is not limited to a motor; for example, an engine may also be used.

[0077] The waveform generator 10 includes a vehicle speed / rotation speed acquiring unit 11 and frequency component group generating units 12 - 1 , . . . 12 -N. If any of the frequency component group generating units 12 - 1 , . . . 12 -N is not required, it is simply referred to as the frequency component group generating unit 12 .

[0078] The vehicle speed / rotation speed acquiring unit 11 obtains the vehicle 300 (see Figure 6 ) acquires the vehicle speed or the rotational speed of the power unit as vehicle information. The vehicle speed / rotational speed acquisition unit 11 is composed of, for example, a vehicle speed sensor. The vehicle speed / rotational speed acquisition unit 11 acquires the vehicle speed or the rotational speed of the power unit based on the rotational speed of the motor or axle (not shown) via the vehicle speed sensor and supplies the information to the gain coefficient calculation unit 20.

[0079] Each frequency component group generation processing unit 12-1, ... 12-N has a corresponding waveform table (timbre). For example, the frequency component group generation processing unit 12-1 has a low-frequency waveform table that contains relatively more low-frequency components, and the frequency component group generation processing unit 12-2 (when N is 2) has a high-frequency waveform table that contains relatively more high-frequency components than the low-frequency waveform table. In addition, the low-frequency waveform table can be composed only of low-frequency components as long as it contains more low-frequency components than high-frequency components. In addition, the high-frequency waveform table can be composed only of high-frequency components as long as it contains more high-frequency components than low-frequency components. In addition, the low-frequency waveform table and the high-frequency waveform table are not limited to waveform tables, and can also be data containing low-frequency waveform signals and high-frequency waveform signals.

[0080] The frequency component group generation processing units 12 - 1 , . . . 12 -N have different waveform tables, and thus the waveform generation unit 10 has a plurality of waveform tables.

[0081] Figure 2 This is a block diagram showing the schematic structure of the waveform generation unit. Figure 2As shown, the waveform generation unit 10 includes a skip table 123 and a generation processing unit 124. The generation processing unit 124 includes a waveform table 125 for forming a timbre. The waveform table 125 is waveform data read by the generation processing unit 124 and is composed of table values. The waveform table 125 is an example of waveform data including multiple frequency components (1 [Hz], 2 [Hz], and 4 [Hz]) with a period of 1 [s].

[0082] 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 speed acquisition unit 11, for example.

[0083] The skip table 123 includes at least one of the vehicle speed step table 121 and the rotation speed step table 122. The vehicle speed step table 121 specifies the skip number (reading width) ΔP based on the vehicle speed [km / h] of the vehicle 300. The rotation speed step table 122 specifies the skip number ΔP based on the rotation speed [rpm] of the power unit. The skip number indicates, for example, the reading width of waveform data when reading waveform table 125. In other words, the skip number indicates the ratio by which waveform table 125 is thinned out, resulting in a speed value when waveform table 125 is replayed at double the speed.

[0084] The skip table 123 stores the skip number ΔP in table format. For example, based on the vehicle speed step table 121, the vehicle speed / rotation speed acquisition unit 11 reads 4 as the skip number ΔP when the vehicle speed is 10 [km / h], and 4 as the skip number ΔP when the vehicle speed is 20 [km / h]. Furthermore, the vehicle speed / rotation speed acquisition unit 11 reads 9 as the skip number ΔP when the vehicle speed is 30 [km / h], and 400 as the skip number ΔP when the vehicle speed is 200 [km / h].

[0085] For example, based on the speed step table 122, the vehicle speed / rotation speed acquisition unit 11 reads 1 as the skip number ΔP when the power unit speed is 600 [rpm], and reads 2 as the skip number ΔP when the power unit speed is 700 [rpm]. Furthermore, the vehicle speed / rotation speed acquisition unit 11 reads 4 as the skip number ΔP when the power unit speed is 800 [rpm], and reads 100 as the skip number ΔP when the power unit speed is 3000 [rpm].

[0086] Thus, after the vehicle speed or power unit rotation speed is acquired by the vehicle speed / rotation speed acquisition unit 11, the waveform generation unit 10 acquires the number of skips ΔP of the read position based on the vehicle speed or rotation speed. Furthermore, the number of skips ΔP in the vehicle speed step table 121 or the rotation speed step table 122 defines the number of skips desired by the user.

[0087] Meanwhile, the generation processing unit 124 is provided in each of the frequency component group generation processing units 12-1, ..., 12-N. In other words, the generation processing unit 124 corresponds to each of the frequency component group generation processing units 12-1, ..., 12-N. Based on the skip number ΔP acquired by the vehicle speed / rotation speed acquisition unit 11, the generation processing unit 124 reads a signal from the waveform table 125 at a position obtained by adding the acquired skip number ΔP to the previously read position. This generates a signal (that is, a waveform table with a skip number ΔP) to be input to the speaker 50.

[0088] Here, the signal generated by the generation processing unit 124 is defined by the following equation (1).

[0089]

Formula 1

[0090] P(t+1)=P(t)+ΔP(t)…(1)

[0091] Here, P(t): pointer, P(0): initial value 0, ΔP(t): skip number.

[0092] As shown in equation (1), the vehicle speed / rotation speed acquisition unit 11 reads the waveform table 125 corresponding to the skip number ΔP at the pointer P(t) corresponding to the previous value based on the skip number ΔP read from the skip table 123 and the previous value of the pointer P(t), thereby generating a signal to be input to the speaker 50. In this case, the waveform data in the waveform table 125 corresponding to the skip number ΔP becomes the signal (timbre).

[0093] Figure 3A 、 Figure 3B This is an explanatory diagram explaining the concept of a generation processing unit reading a signal (waveform data) at a position obtained by adding the acquired skip number to the previous reading position.

[0094] Figure 3A In the example, the concept of generating a signal (waveform data) read by the processing unit 124 from the waveform table 126 is represented when the skip number ΔP is 2. Figure 3A As shown, the generation processing unit 124 reads waveform data (waveform table 127) from the previous reading position at a double cycle (two round trips) with respect to the waveform data (waveform table 126) having a cycle of 1 second.

[0095] Figure 3B For example, the concept of generating a signal for the processing unit 124 to read the waveform table 128 when the skip number ΔP is 3 is shown. Figure 3B As shown, the generation processing unit 124 reads waveform data (waveform table 129 ) from the previous reading position at a triple cycle (three round trips) with respect to the waveform data (waveform table 128 ) having a cycle of 1 second.

[0096] Here, the waveform tables 126 and 128 hold the values of the signal (waveform data) in a table format for each cycle. This embodiment is characterized in that the waveform tables 126 and 128 are used by the waveform generator 10 to read the waveform data.

[0097] Figure 4 This is an explanatory diagram showing an example of processing for waveform table synthesis. Figure 4 , a process of synthesizing a waveform table 134 having waveform data of three frequency components from a waveform table 131 of a frequency of 1 [Hz], a waveform table 132 of a frequency of 1.25 [Hz], and a waveform table 133 of a frequency of 1.5 [Hz] is shown.

[0098] The three waveform tables 131, 132, and 133 each have different periods, making it impossible to achieve synchronization in 1-second units. Therefore, in this embodiment, since waveform table 134 having three frequency components is generated, the ratio of the frequencies of waveform tables 131, 132, and 133 is set to an integer multiple while maintaining the ratio, and the minimum time [s] (multiplier) for achieving synchronization is determined from the value that makes this value an integer. The waveform data of waveform tables 131, 132, and 133 can achieve synchronization at each timing by setting the ratio of the frequencies to an integer so that their starting and ending points have the same value. Therefore, in this embodiment, the waveform data of each waveform table 131, 132, and 133 are synthesized, with the minimum time [s] for achieving synchronization of waveform tables 131, 132, and 133 as a period, thereby generating waveform table 134 containing three frequency components.

[0099] As described above, in this embodiment, after the ratio of the frequencies of the waveform tables 131 , 132 , and 133 is set to an integer, the minimum required time (minimum time) of the data sequence of the waveform data is determined.

[0100] exist Figure 4 In this case, the frequency ratios of waveform table 131 (1 Hz), waveform table 132 (1.25 Hz), and waveform table 133 (1.5 Hz) are 1:1.25:1.5. Integer multiples of these frequency ratios yield 4:5:6 and 100:125:150. In this case, the minimum time (s) required to synchronize waveform tables 131, 132, and 133 is 4:5:6, calculated as (1:1.25:1.5) x 4, resulting in a value of 4:5:6. This is determined as 4 s. Once the minimum time (4 s) is determined, the waveform data in waveform table 131 corresponds to four cycles, the waveform data in waveform table 132 corresponds to five cycles, and the waveform data in waveform table 133 corresponds to six cycles.

[0101] Waveform table 134 then adds together the periodic data (four, five, or six periods) of waveform tables 131, 132, and 133, each representing an integer multiple of the minimum time (4 seconds) required to synchronize waveform tables 131, 132, and 133. This generates waveform data whose minimum time (seconds) constitutes one period. The resulting waveform table 134 is a periodic waveform table with continuous end and start points, and contains multiple frequency components.

[0102] In other words, in this embodiment, the waveform table 134 is formed by waveform data in which the minimum multiplier (that is, the minimum time) that makes all the ratios of the frequencies integers is set as the period of the waveform table while maintaining the ratios of the multiple frequencies.

[0103] In this manner, the waveform table 134 including a plurality of frequency components is generated from the waveform data of the waveform tables 131 , 132 , and 133 including the frequency components desired by the user.

[0104] return Figure 1 The gain coefficient calculation unit 20 of the active driving sound generating device 100 is composed of an accelerator opening sensor 21, an acceleration calculation unit 22, a speed change calculation unit 23, a vehicle speed / speed gain table 24, an accelerator gain table 25, an acceleration gain table 26, and a speed change gain table 27.

[0105] The accelerator opening sensor 21 detects the opening of the accelerator pedal when a user steps on the accelerator pedal of the vehicle 300 (this will be referred to as the accelerator opening θ).

[0106] 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.

[0107] 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.

[0108] The vehicle speed / rotation speed gain table 24 has a characteristic of applying a gain to the supplied vehicle speed or power unit rotation speed. The accelerator gain table 25 has a characteristic of applying a gain to the detected accelerator opening θ. The acceleration gain table 26 has a characteristic of applying a gain to the calculated acceleration Δa. The rotation speed change gain table 27 has a characteristic of applying a gain to the calculated rotation speed change Δb.

[0109] Furthermore, the vehicle speed / rotation speed gain table 24 , the accelerator gain table 25 , the acceleration gain table 26 , and the rotation speed change gain table 27 are appropriately set with predetermined characteristics desired by the user in a table format.

[0110] The gain control unit 30 of the active running sound effect generator 100 is configured with a plurality of gain adjustment units 31, 3N. The gain control unit 30 receives signals u1, 3N generated by the frequency component group generation processing units 12-1, 12-N from the waveform generator 10, and receives coefficients for adjusting the gain of each signal u1, 3N from the gain coefficient calculator 20.

[0111] Each of the plurality of gain adjustment units 31, ..., 3N corresponds to a signal u1, ..., uN generated from the waveform table of the frequency component group generation processing unit 12-1, ..., 12-N. Thus, each gain adjustment unit 31, ..., 3N adjusts the gain of the corresponding signal u1, ..., uN generated by the frequency component group generation processing unit 12-1, ..., 12-N using the gain coefficient obtained from the gain coefficient calculation unit 20.

[0112] Figure 5 This is an explanatory diagram showing characteristics of gain applied by the gain adjustment section of the gain control section to the signal acquired from the waveform generation section.

[0113] like Figure 5 As shown, when the vehicle speed or rotational speed is relatively low, the gain control unit 30 increases (raises) the gain of the low-frequency waveform table by using the gain G1 representing the low-frequency component. On the other hand, when the vehicle speed or rotational speed is relatively high, the gain control unit 30 increases the gain of the high-frequency waveform table by using the gain G2 representing the high-frequency component.

[0114] Figure 5 In FIG, the gain G1 represents the characteristics of the gain of the low-frequency component (low-frequency waveform signal), and the gain G2 represents the characteristics of the gain of the high-frequency component (high-frequency waveform signal).

[0115] For example, 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. In this case, when the vehicle speed or rotation speed is relatively small, the gain adjustment unit 31 emphasizes the low-frequency component of the low-frequency waveform table of the output frequency component group generation processing unit 12-1 through the gain G1.

[0116] On the other hand, when the vehicle speed or rotation speed is relatively high, the gain adjustment unit 32 (when N is 2) emphasizes the high-frequency components of the high-frequency waveform table of the output frequency component group generation processing unit 12 - 2 by the gain G2 .

[0117] The sound control unit 40 (see Figure 1) has an image control processing unit 41. The image control processing unit 41 changes (adjusts) the magnitude of the output of each of the plurality of speakers 50 (51, 52, ... 5S) with respect to the plurality of signal components y1, ... yN.

[0118] 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).

[0119]

Formula 2

[0120]

[0121] Here, S S : the output sound of the S-th speaker; n: the frequency component number; N: the total number of frequency component groups; K nS : Gain coefficient when the nth frequency component group is output from the Sth speaker; D nS : The time delay when the nth frequency component group is output from the Sth speaker.

[0122] As shown in equation (2), the image control processing unit 41 multiplies the signals u1, ..., uN generated by the frequency component group generation processing units 12-1, ..., 12-N by the gain coefficients set for each speaker 50 to adjust the magnitude and delay time. As a result, the sound output from each speaker 51, 52, ..., 5S becomes the sum (result) of the frequency components after the magnitude adjustments.

[0123] Thus, the audio-visual control processing unit 41 outputs a relatively small low-frequency waveform signal (low-frequency waveform component) and a relatively large high-frequency component from the speaker 51 arranged in the front of the vehicle 300, and outputs a relatively large low-frequency waveform signal (low-frequency waveform component) and a relatively small high-frequency component from the speaker 5S arranged at the rear of the vehicle 300 compared to the speakers 51 and 52 arranged in the front.

[0124] Furthermore, the image control processing unit 41 can adjust the phase of the signal of each speaker 50 for each of the plurality of signal components y1, ..., yN. Therefore, the speaker 51 located 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 located at the rear of the vehicle 300.

[0125] Figure 6 FIG. 1 is a block diagram showing the structure of the audio and video control processing unit. Figure 6As shown, the image control processing unit 41 includes amplifiers 421, 422, ... 42S, 441, 442, ... 44S for multiplying each of the plurality of signal components y1, ... yN by a constant for each of the speakers 51, 52, ... 5S.

[0126] Figure 6 In the case where speakers 51, 52, ..., 5S are provided, the sound image control processing unit 41 generates the signal component y1 of the processing unit 12-1, for example, by setting 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. As a result, the sound image control processing unit 41 localizes the sound image of the signal component y1 toward the front of the vehicle cabin.

[0127] Meanwhile, the sound image control processing unit 41 generates the signal component yN of the processing unit 12-N, which assumes the frequency component group of exhaust sound. For example, the sound image control processing unit 41 sets a coefficient of 0.0 for amplifier 441, a coefficient of 0.5 for amplifier 442, and a coefficient of 1.0 for amplifier 44S. This causes the sound image of the signal component yN to be localized behind the vehicle cabin.

[0128] Thus, speaker 51 outputs relatively greater high-frequency components than speakers 52 and 5S, and speaker 52 outputs relatively greater high-frequency components than speaker 5S. On the other hand, speaker 5S outputs relatively greater low-frequency components than speakers 51 and 52, and speaker 52 outputs relatively greater low-frequency components than speaker 51. Alternatively, the audio and video control processing unit 41 may divide the plurality of speakers 50 (51, 52, ..., 5S) into groups for the front and rear of the vehicle compartment and control them collectively.

[0129] Furthermore, the image control processing unit 41 includes delay adjustment elements 431 , 432 , . . . 43S, 451 , 452 , . . . 45S for adjusting the phase of the signal of each of the speakers 51 , 52 , . . . 5S for each of the plurality of signal components y1 , . . . yN.

[0130] Delay adjustment elements 431, 432, ..., 43S, 451, 452, ..., 45S set delay times using digital values for each signal component y1, ..., yN. This allows speaker 51, located at the front of vehicle 300, to output high-frequency waveform components earlier and low-frequency waveform signals (low-frequency waveform components) later than speakers 52, ..., 5S, located at the rear of vehicle 300.

[0131] Thus, speaker 51 uses adder 461 to add the signal amplified by amplifier 421 and delayed by delay adjustment element 431, and the signal amplified by amplifier 441 and delayed by delay adjustment element 451, and outputs the added signal s1 into the vehicle cabin. Speaker 52 uses adder 462 to add the signal amplified by amplifier 422 and delayed by delay adjustment element 432, and the signal amplified by amplifier 442 and delayed by delay adjustment element 452, and outputs the added signal s2 into the vehicle cabin. Speaker 5S uses adder 46S to add the signal amplified by amplifier 42S and delayed by delay adjustment element 43S, and the signal amplified by amplifier 44S and delayed by delay adjustment element 45S, and outputs the added signal sS into the vehicle cabin.

[0132] [Operation of the active driving sound generator]

[0133] Action 1

[0134] Next, refer to Figure 1 、 Figures 7A to 9B , while explaining the operation of the active running sound generating device 100 according to the first embodiment.

[0135] The active running sound effect generator 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 acquiring unit 11. The vehicle speed / rotation speed acquiring unit 11 acquires the skip number ΔP based on the acquired vehicle speed or the rotation speed of the power unit.

[0136] The frequency component group generation processing units 12 - 1 , . . . 12 -N (generation processing unit 124 ) read the signal of the position after adding the skip number ΔP at the reading position P(t) of each waveform table, and input it to the gain control unit 30 .

[0137] The gain coefficient calculation unit 20 calculates the gain coefficients of each signal u1, ··uN from the vehicle speed / speed gain table 24, the accelerator gain table 25, the acceleration gain table 26, and the acceleration gain table 26 based on the accelerator opening θ of the accelerator opening sensor 21, the vehicle speed or the speed of the power unit obtained by the vehicle speed / speed acquisition unit 11.

[0138] The gain control unit 30 controls (adjusts) the corresponding gain of each signal u1 , . . . uN generated from the plurality of waveform tables of the frequency component group generation processing units 12 - 1 , . . . 12 -N using the gain coefficient calculated by the gain coefficient calculation unit 20 .

[0139] The sound control unit 40 changes the magnitude of the output of each of the plurality of speakers 50 relative to each signal component y1, ...yN and inputs the signal to each speaker 50. Thus, each speaker 50 can output the signal u1, ...uN generated by the waveform generator 10.

[0140] Action 2

[0141] Furthermore, in this embodiment, the active running sound effect generator 100 includes a waveform table for each of the frequency component group generation processing units 12-1, ..., 12-N in the waveform generation unit 10, thereby providing multiple waveform tables. Therefore, the waveform generation unit 10 can accept user operations and switch between the multiple waveform tables in response to the user's operation.

[0142] Figures 7A to 7C This is an explanatory diagram showing a case where a desired waveform table can be selected from a plurality of waveform tables included in the frequency component group generation processing section of the waveform generation section.

[0143] Figure 7A Indicates a display screen speaker provided in the vehicle 300. Figure 7A As shown, the display screen audio 200 is provided with a volume screen 201 and a tone screen 202.

[0144] The volume screen 201 receives on / off of customized adjustment of the volume by the user, and when on, the volume can be adjusted.

[0145] The tone screen 202 switches tones by the button according to the user's selection operation. For example, the tone of the electric vehicle (EV) movement and the tone of the futuristic EV can be selected in the tone screen 202. In this case, if the user selects the electric vehicle (EV) movement tone, the frequency component group generation processing unit 12-1, ... 12-N of the waveform generation unit 10 is selected. Figure 7B On the other hand, if the user selects the futuristic EV tone, the frequency component group generation processing units 12-1, ... 12-N of the waveform generation unit 10 select Figure 7C Waveform table 1202 is shown.

[0146] Figure 7B The waveform table 1201 shows a low-frequency waveform table as an example of the timbre of the powerful EV movement, for example. Figure 7C The waveform table 1202 shows a high-frequency waveform table as an example of the futuristic EV sound.

[0147] The waveform table 1201 corresponds to, for example, the frequency component group generation processing unit 12 - 1 , and the waveform table 1202 corresponds to, for example, the frequency component group generation processing unit 12 - 2 . This allows the user to select a waveform table that outputs a personalized tone.

[0148] Furthermore, the waveform table for outputting the personalized timbre may be added by the user. For example, the timbre screen 202 may include a button 203 for accepting the addition of a timbre by the user.

[0149] Action 3

[0150] Figure 8A This is an explanatory diagram showing the structure of a button for adding a tone (wave table) in the tone screen of the display sound. Figure 8B This diagram illustrates a waveform table added by the user to the waveform generation unit. Waveform table 1203 is waveform data downloaded by the user from the Internet as timbre data. Like waveform table 134, waveform table 1203 is a periodic waveform table with a continuous end point and starting point, and contains multiple frequency components.

[0151] Figure 8A In the waveform generator 10, the user can add a desired waveform table to the waveform generator 10 by pressing the button 203. Thus, the waveform generator 10 can add the waveform table 1203 to a plurality of waveform tables (frequency component group generation processing units 12-1, ..., 12-N).

[0152] The waveform generating unit 10 can switch the waveform table for generating the signal input to the speaker 50 from among the plurality of waveform tables to the added waveform table 1203. In this case, the user can add the waveform table 1203 from, for example, the Internet or an external memory, and can select to output the signal of the added waveform table 1203.

[0153] In this manner, the waveform generation unit 10 can accept the addition of the waveform table 1203 and can accept the selection of waveform data (timbre) in the waveform table 1203 to be output to the speaker 50 .

[0154] Action 4

[0155] Furthermore, the waveform generating unit 10 is configured to include a vehicle speed / rotation speed acquiring unit 11 , and the vehicle speed / rotation speed acquiring unit 11 includes a skip table 123 .

[0156] The skip table 123 may include, for example, a vehicle speed step table 121 and a rotation speed step table 122 , and may include a plurality of them.

[0157] Figure 9A1 is an explanatory diagram showing the first skip table 1231. Figure 9A As shown, first skip table 1231 exponentially increases from a lower limit to an upper limit as vehicle speed or power unit rotational speed increases, and then returns to the lower limit after reaching the upper limit. In first skip table 1231, after the skip count returns to the lower limit, it increases exponentially again. Thus, first skip table 1231 can generate an infinite scale signal.

[0158] in addition, Figure 9B 1232 is an explanatory diagram showing the second skip table 1232. Figure 9B As shown, second skip table 1232 increases the frequency in proportion to increases in vehicle speed or power unit rotational speed, and then decreases the frequency by a predetermined amount after the vehicle speed or rotational speed reaches a predetermined value. In second skip table 1232, after decreasing the frequency, the frequency is again increased in a stepwise manner in proportion to increases in vehicle speed or power unit rotational speed. Thus, second skip table 1232 can generate an engine style signal.

[0159] For example, in Figure 7A or Figure 8A In the tone color screen 202 of the EV, if the tone color of the future sense EV is selected by the user's selection operation, the Figure 9A On the other hand, in the tone color screen 202, if the tone color of the engine style is selected by the user's selection operation, the selected Figure 9B The second skip table 1232.

[0160] Thus, when the first skip table 1231 is selected, the waveform generating unit 10 can generate a futuristic EV signal (infinite scale signal) in the vehicle speed / rotation speed acquiring unit 11 .

[0161] On the other hand, when the second skip table 1232 is selected, the waveform generating unit 10 can generate the engine style signal in the vehicle speed / rpm acquiring unit 11 .

[0162] In particular, when the first skip table 1231 (infinite scale signal) is selected, the waveform generating unit 10 does not intentionally control the low-frequency waveform signal and the high-frequency waveform signal according to the position of the speaker 50, regardless of whether the engine-style tone can be output, but outputs them originally from the speakers 51, 52,...5S, thereby being able to output an infinite scale signal.

[0163] As described above, the active driving sound effect generator 100 of the first embodiment includes a waveform generator 10 and a speaker 50. The waveform generator 10 generates signals u1 through uN from waveform tables 125, 134, etc. based on vehicle information. The speaker 50 outputs the signals u1 through uN generated by the waveform generator 10. The waveform tables 125, 134, etc. are periodic waveform tables with consecutive end and start points, and contain multiple frequency components.

[0164] With this configuration, waveform tables 125, 134, etc., included in waveform generator 10, include multiple frequency components. This reduces the amount of calculation required compared to conventional techniques (e.g., Japanese Patent Application Laid-Open Nos. 2015-229403 and 2019-128378), which generate multiple frequency components from a waveform table representing a single frequency component (e.g., a sine wave) and synthesize (superimpose) the resulting harmonic acoustic signal.

[0165] In other words, the active running sound effect generator 100 of the first embodiment can not only read the waveform data of the waveform tables 125, 134, etc., which are periodic waveform tables, but also generate the signals u1 to uN to be output from the speaker 50. Thus, the active running sound effect generator 100 can generate an acoustic signal without performing calculations that impose a heavy processing burden.

[0166] In particular, if you use Figure 4 As described above, the waveform data in the waveform table 134 included in the waveform generator 10 includes three (or more) frequency components. The waveform table 134 is a periodic waveform table in which the end and start points of the waveform data are continuous, and includes three (or more) frequency components.

[0167] The waveform table 134 adds integer multiples of the period data of the waveform tables 131 , 132 , and 133 according to the minimum time (4 s) that allows synchronization between the waveform tables 131 , 132 , and 133 , thereby generating waveform data without discontinuity.

[0168] Comparative Example

[0169] Here, a comparative example will be described.

[0170] Figure 14 An explanatory diagram showing a comparative example of synthesizing waveform tables including a plurality of frequency components. Figure 14 , a process of synthesizing a waveform table 164 having waveform data of three frequency components from a waveform table 161 of a frequency of 1 [Hz], a waveform table 162 of a frequency of 1.25 [Hz], and a waveform table 163 of a frequency of 1.5 [Hz] is shown.

[0171] The three waveform tables 161 , 162 , and 163 have different periods. Therefore, when waveform data corresponding to 1 second are directly added by the adder 135 , a waveform table 164 having no period is synthesized.

[0172] In particular, since waveform table 164 is created by summing the waveform data from waveform tables 161, 162, and 163 using their respective 1-second waveform data, the sum of the intermediate values within each cycle does not produce a complete cycle of waveform data. In other words, in the 1-second waveform data of waveform table 164, although the starting point is 0, the ending point is 1, and the starting and ending points do not match. In this case, repeatedly reading the waveform data from waveform table 164 will cause discontinuity due to the mismatch between the starting and ending points. As a result, if waveform table 164 is used as a repetitive, continuous periodic waveform table, the active running sound effect generator 100 will experience audible asynchrony between the starting and ending points.

[0173] Therefore, in the prior art, in order to avoid sound asynchrony caused by discontinuity of the waveform table, a plurality of waveform tables for a single frequency component are prepared, various prescribed operations are performed using each waveform table, and then synthesized by an adder.

[0174] In contrast, the waveform table 134 of the first embodiment determines the minimum required waveform data sequence (minimum time) as one cycle, after the ratio of the frequencies of each waveform table 131, 132, and 133 becomes an integer. Specifically, waveform table 134 uses the minimum time [s] required to synchronize each waveform table 131, 132, and 133 as one cycle, and combines the cycle data (waveform data) of each waveform table 131, 132, and 133 as an integer multiple to generate the desired waveform data. This prevents the sound from becoming out of sync midway within any cycle, ensuring sound continuity even when reading repeatedly. In particular, waveform table 134 can be generated by synthesizing waveform tables containing the desired frequency components, making it easy to adjust the user's desired timbre.

[0175] As described above, the active running sound generating device 100 according to the first embodiment can easily adjust the timbre, and thus can generate a running sound with a high sense of reality.

[0176] The waveform generator 10 includes multiple waveform tables and generates signals u1, ..., uN from the multiple waveform tables. The active running sound effect generator 100 includes multiple gain adjustment units 31, ..., 3N corresponding to the signals u1, ..., uN generated by the waveform generator 10 from the multiple waveform tables.

[0177] According to this configuration, each frequency component group generation processing unit 12 - 1 , . . . 12 -N has a waveform table, and the active running sound effect generating device 100 has gain adjustment units 31 , . . . 3N corresponding to each frequency component group generation processing unit 12 - 1 , . . . 12 -N.

[0178] Thus, the active running sound effect generating device 100 can adjust the gains of the generated signals u1,...uN respectively, and can further overlap the gain-adjusted signals u1,...uN, thereby enabling chord combination and generating desired complex timbre.

[0179] Furthermore, waveform generator 10 is configured to include a waveform table 1201 (low-frequency waveform table) containing a relatively high proportion of low-frequency components, and a waveform table 1202 (high-frequency waveform table) containing a relatively high proportion of high-frequency components compared to waveform table 1201. Vehicle information is vehicle speed or power unit rotational speed. When the vehicle speed or rotational speed is relatively low, the gain of waveform table 1201 is increased. On the other hand, when the vehicle speed or rotational speed is relatively high, the gain of waveform table 1202 is increased.

[0180] According to this composition, Figure 5 As shown, in the low vehicle speed range, the waveform generation unit 10 increases the gain of the low-frequency components of the waveform table 1201 by using the gain G1, and reduces the gain of the high-frequency components of the waveform table 1202 by using the gain G2. This generates a powerful signal, such as an engine sound. Thus, the waveform generation unit 10 can generate a sound with a sense of acceleration.

[0181] Furthermore, as vehicle 300 accelerates, waveform generator 10 increases the gain of the high-frequency components of waveform table 1202 using gain G2 in the high-vehicle speed range, and reduces the gain of the low-frequency components of waveform table 1201 using gain G1, thereby generating a signal with a light exhaust sound. This allows waveform generator 10 to generate a refreshing sound.

[0182] In addition, as in action 2, use 7A to 7C As described above, the waveform generation unit 10 includes the plurality of waveform tables 1201 and 1202 , and the plurality of waveform tables 1201 and 1202 can be switched by a user operation.

[0183] With this configuration, the waveform generator 10 can switch between the powerful EV sports sound and the futuristic EV sound by user selection on the sound color screen 202 of the display speaker 200 , thereby providing more pleasant sounds to the occupants of the vehicle 300 .

[0184] In addition, as in action 3, use Figure 8A as well as Figure 8BAs described above, the plurality of waveform tables may include the waveform table 1203 added by a user operation, and the waveform generator 10 may be capable of switching the waveform table for generating signals u1 , . . . uN among the plurality of waveform tables to the added waveform table 1203 .

[0185] According to this configuration, the waveform generating unit 10 can add waveform data of a user-desired tone in addition to the waveform data provided as standard equipment of the active running sound generating device 100 , thereby further improving the enjoyment of the active running sound generating device 100 .

[0186] In addition, if you use Figure 2 As described above, waveform generator 10 may include a skip table 123 and a generation processing unit 124. Skip table 123 acquires a skip number ΔP for a read position based on vehicle information. Generation processing unit 124 reads a signal at a position obtained by adding the acquired skip number ΔP to the previous read position in the waveform table, and generates signals u1, ..., uN, which are input to speaker 50.

[0187] According to this configuration, the waveform generator 10 only needs to read the skip number ΔP from the skip table 123 according to the driving state of the vehicle 300 and add the skip number ΔP to the previous read position, thereby further reducing the amount of calculation.

[0188] In addition, if Figure 9A as well as Figure 9B As shown, the skip table 123 may include a plurality of first skip tables 1231 and second skip tables 1232, and the skip tables may be switched by a user's selection operation.

[0189] With this configuration, waveform generator 10 can switch frequencies based on the vehicle speed or power unit rotational speed, using a skip number ΔP corresponding to the driving state of vehicle 300, thereby further improving user preference. In particular, a desired timbre can be achieved simply by switching waveform data (table-formatted data values) such as first skip table 1231 and second skip table 1232. This makes it easy to switch to a desired skip table 123 without having to change software calculation formulas.

[0190] In addition, the vehicle information is the vehicle speed or the rotation speed of the power unit, Figure 9A The first skip table 1231 may be set to increase from a lower limit value to an upper limit value in an exponential manner based on an increase in vehicle speed or rotation speed, and to return to the lower limit value after reaching the upper limit value.

[0191] According to this composition, Figure 9A The first skip table 1231 can generate an infinite scale signal. Thus, the waveform generating unit 10 can generate an infinite scale signal by Figure 9AThe first skip table 1231 easily generates an infinite scale.

[0192] <Second embodiment>

[0193] [General Structure of Active Driving Sound Generator]

[0194] Figure 10 This is a block diagram showing a schematic configuration of a vehicle equipped with an active running sound generating device according to a second embodiment.

[0195] Figure 10 As shown, the active running sound generator 101 of the second embodiment is configured by further including frequency characteristic adjustment processing units 13-1, ..., 13-N in addition to the waveform generator 10 of the first embodiment. Note that, unless it is necessary to specify any one of the frequency characteristic adjustment processing units 13-1, ..., 13-N, they will simply be referred to as the frequency characteristic adjustment processing unit 13.

[0196] Each frequency characteristic adjustment processing unit 13-1, ..., 13-N includes a bandpass filter applied to the signal u1, ..., uN generated by the corresponding frequency component group generation processing unit 12, ..., 12-N (generation processing unit 124). The bandpass filter has a passband between the frequency of the signal generated by the upper limit value of the skip number ΔP of the skip table and the frequency of the signal generated by the lower limit value.

[0197] Figure 11A It is an explanatory diagram showing coefficients of a bandpass filter included in the frequency characteristic adjustment processing unit. Figure 11B It is an explanatory diagram showing the frequency characteristics based on the filter coefficients.

[0198] Each frequency characteristic adjustment processing unit 13 - 1 , ... 13 -N constitutes a bandpass filter that passes a predetermined frequency band based on a predetermined filter coefficient. Figure 11B The frequency characteristics shown are provided with a predetermined passband by combining a low-pass filter that does not attenuate low-frequency components but gradually reduces frequency components higher than a predetermined cutoff frequency, and a high-pass filter that does not attenuate high-frequency components but gradually reduces frequency components lower than a predetermined cutoff frequency.

[0199] Figure 12A : is an explanatory diagram showing the signal input to the frequency characteristic adjustment processing unit. Figure 12A As shown, when the signals u1 , . . . uN input to the frequency characteristic adjustment processing units 13 - 1 , . . . 13 -N are switched from high frequency to low frequency according to changes in vehicle speed, the switching of frequencies is clearly output as indicated by arrow 150 .

[0200] In contrast, Figure 12B This figure shows an explanatory diagram of a signal output from the frequency characteristic adjustment processing unit. Figure 12B As shown, the signals f1, . . . fN output from the frequency characteristic adjustment processing units 13-1, . . . 13-N are respectively applied with respect to the signals u1, . . . uN input to the frequency characteristic adjustment processing units 13-1, . . . 13-N. Figure 11B The bandpass filter with such frequency characteristics gradually reduces high-frequency components and low-frequency components. Therefore, when the signals f1,...fN output from the frequency characteristic adjustment processing units 13-1,...13-N switch from high-frequency components to low-frequency components, each frequency component can be faded in and out.

[0201] [Operation of the active driving sound generator]

[0202] While referring to Figure 13 , while explaining the operation of the active running sound generating device of the second embodiment.

[0203] Figure 13 This is an explanatory diagram showing a configuration for switching filter coefficients of the active running sound generating device according to the second embodiment.

[0204] like Figure 13 As shown, the frequency characteristic adjustment processing unit 13 includes a filter coefficient setting table 143. The filter coefficient setting table 143 includes filter coefficients to be set for the bandpass filter in accordance with the vehicle speed range.

[0205] For example, before the speed of vehicle 300 reaches 60 kph, data set 144 is applied, and predetermined filter coefficients (0.0, 0.32, ..., 0.01) are applied to the bandpass filter. Furthermore, within the speed range of vehicle 300 from 100 kph to 160 kph, data set 145 is applied, and predetermined filter coefficients (0.0, 0.35, ..., 0.00) are applied to the bandpass filter.

[0206] Thus, the frequency characteristic adjustment processing unit 13 switches the filter coefficient according to the vehicle speed range, and applies a bandpass filter to the signals u1 , . . . uN input to the frequency characteristic adjustment processing units 13 - 1 , . . . 13 -N.

[0207] As described above, the active running sound effect generator 101 of the second embodiment includes a bandpass filter in the waveform generator 10. The bandpass filter is applied to the signals u1, ..., uN generated by the waveform generator 10. Furthermore, the bandpass filter has a passband between the frequency of the signal generated by the upper limit value of the skip table 123 and the frequency of the signal generated by the lower limit value.

[0208] According to this configuration, the active running sound generating device 101 of the second embodiment can apply a bandpass filter to the signals u1,...uN input to the frequency characteristic adjustment processing units 13-1,...13-N, thereby eliminating the frequency switching sensation accompanying the change in vehicle speed and generating a natural sound.

Claims

1. An active driving sound effect generating device, which is mounted on a vehicle, wherein the active driving sound effect generating device is characterized by having: A waveform generating section that generates a signal from a waveform table based on vehicle information; and a speaker that outputs the signal generated by the waveform generating unit, The waveform table is a periodic waveform table with a continuous end point and a continuous start point, and contains multiple frequency components.

2. The active driving sound effect generating device according to claim 1, characterized in that: The waveform generating unit includes a plurality of the waveform tables, and generates signals from each of the plurality of the waveform tables. The active running sound effect generating device further includes a plurality of gain adjustment units corresponding to the signals generated from the plurality of waveform tables.

3. The active driving sound effect generating device according to claim 2, characterized in that: The waveform generating unit includes a low-frequency waveform table containing relatively more low-frequency components and a high-frequency waveform table containing relatively more high-frequency components than the low-frequency waveform table. The vehicle information is the vehicle speed or the rotation speed of the power unit, When the vehicle speed or the rotation speed is relatively low, the gain of the low-frequency waveform table is increased. On the other hand, when the vehicle speed or the rotation speed is relatively high, the gain of the high-frequency waveform table is increased.

4. The active driving sound effect generating device according to claim 1, characterized in that: The waveform generating unit includes a plurality of the waveform tables. The plurality of waveform tables can be switched by a user operation.

5. The active driving sound effect generating device according to claim 4, characterized in that: The plurality of waveform tables include a waveform table added by a user operation, The waveform generating unit can switch a waveform table for generating the signal from among the plurality of waveform tables to the added waveform table.

6. The active driving sound effect generating device according to claim 1, characterized in that: The waveform generating unit comprises: a skip table for obtaining a skip number of a read position based on the vehicle information; and A generation processing unit reads a signal at a position obtained by adding the acquired skip number to a position read last time in the waveform table, and generates a signal to be input to the speaker.

7. The active driving sound effect generating device according to claim 6, characterized in that: The skip table is provided with multiple Switched by user selection operation.

8. The active driving sound effect generating device according to claim 6, characterized in that: The vehicle information is the vehicle speed or the rotation speed of the power unit, The skip table increases exponentially from a lower limit value to an upper limit value based on an increase in the vehicle speed or the rotation speed, and returns to a lower limit value after reaching the upper limit value.

9. The active driving sound effect generating device according to claim 8, characterized in that: The waveform generating unit includes a bandpass filter applied to the signal generated by the generating processing unit. The bandpass filter has a passband between a frequency of a signal generated by an upper limit value and a frequency of a signal generated by a lower limit value of the skip table.

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