Active sound effect generator

Abstract

To provide more excellent active sound effect generation device and active sound effect generation method.SOLUTION: An active sound effect generation device 10 which allows a speaker 12 to output effect sound toward an interior of a vehicle driven by a drive source includes: a signal generation part 18 for generating an effect sound signal being a signal for allowing the speaker to output effect sound; and an output part 20 for outputting the effect sound signal generated by the signal generation part to the speaker. When launch control is determined to be ready, the signal generation part generates the effect sound signal for allowing the speaker to output first effect sound having a component of a first frequency as a main component.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an active sound effect generating device and an active sound effect generating method. [Background technology]

[0002] Patent Document 1 below discloses a sound effect generating device that generates sound effects from a speaker toward the interior of a vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4395170 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a need for a better active sound effect generating device and method.

[0005] The present invention aims to solve the above-mentioned problems. [Means for solving the problem]

[0006] A first aspect of the present disclosure is an active sound effect generation device that causes a speaker to output a sound effect toward the interior of a vehicle driven by a drive source, the active sound effect generation device comprising: a determination unit that, when an operation to activate launch control that improves acceleration performance when the vehicle starts is received, determines whether the launch control is in preparation; a signal generation unit that generates a sound effect signal that is a signal that causes the speaker to output the sound effect; and an output unit that outputs the sound effect signal generated by the signal generation unit to the speaker; and when the determination unit determines that the launch control is in preparation, the signal generation unit generates the sound effect signal that causes the speaker to output a first sound effect that has a first frequency component as a main component.

[0007] A second aspect of the present disclosure is an active sound effect generation method for outputting a sound effect from a speaker toward the interior of a vehicle driven by a drive source, the active sound effect generation method including: a determination step for determining whether or not the launch control is in preparation when an operation to activate launch control that improves acceleration performance when the vehicle starts is received; a signal generation step for generating a sound effect signal that is a signal for outputting the sound effect from the speaker; and an output step for outputting the sound effect signal generated in the signal generation step to the speaker; and if it is determined in the determination step that the launch control is in preparation, the active sound effect generation method generates the sound effect signal in the signal generation step for outputting a first sound effect from the speaker that has a first frequency component as a main component. [Effects of the Invention]

[0008] The present invention can provide a better active sound effect generating device and active sound effect generating method. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a functional block diagram of an active sound effect generation device according to an embodiment. [Figure 2] FIG. 2 is a functional block diagram of a signal generating unit according to an embodiment. [Figure 3] FIG. 3 is an image diagram showing the frequency bands of the order sounds and the frequency bands of the background sounds. [Figure 4] FIG. 4 is a graph showing frequency components of the electric motor sound and frequency components of a synthesized sound of the electric motor sound and a sound effect. [Figure 5] FIG. 5 is a diagram illustrating sound effects when launch control is activated. [Figure 6] FIG. 6 is a functional block diagram showing a first sound generation signal generating section in one embodiment. [Figure 7] FIG. 7 is a functional block diagram showing a first-order sound signal generating unit in one embodiment. [Figure 8] FIG. 8 is a functional block diagram showing a first background sound signal generating unit according to an embodiment. [Figure 9] FIG. 9 is a flowchart of the sound effect generation process performed in the active sound effect generation device according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] An active sound effect generating device capable of outputting sound effects into the vehicle cabin that give the driver a sense of exhilaration when launch control, which improves acceleration performance when the vehicle starts, is activated, has not previously been proposed.

[0011] The active sound effect generation device of the present disclosure can output sound effects into the vehicle cabin that give the driver a sense of exhilaration when launch control is activated.

[0012] [One embodiment] [Configuration of active sound effect generator] 1 is a functional block diagram of an active sound effect generation device 10 according to an embodiment. The active sound effect generation device 10 is mounted on a vehicle driven by an electric motor. Vehicles driven by electric motors include BEVs (Battery Electric Vehicles), HEVs (Hybrid Electric Vehicles), PHEVs (Plug-in Hybrid Electric Vehicles), and FCEVs (Fuel Cell Electric Vehicles).

[0013] The active sound effect generating device 10 is a device that outputs sound effects from a speaker 12 provided in the interior of the electric vehicle. The sound effects increase the appeal of the electric vehicle to the passengers.

[0014] The active sound effect generation device 10 has a calculation unit 14 and a storage unit 16. The calculation unit 14 is a processor such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit).

[0015] The calculation unit 14 functions as a signal generation unit 18 and an output unit 20. The signal generation unit 18 and the output unit 20 are realized by the calculation unit 14 executing a program stored in the storage unit 16.

[0016] At least a part of the signal generating unit 18 and the output unit 20 may be realized by an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array). At least a part of the signal generating unit 18 and the output unit 20 may be realized by an electronic circuit including discrete devices.

[0017] The storage unit 16 is configured by a volatile memory (not shown) and a nonvolatile memory (not shown), which are computer-readable storage media. The volatile memory is, for example, a random access memory (RAM). The nonvolatile memory is, for example, a read-only memory (ROM), a flash memory, etc. Data and the like are stored, for example, in the volatile memory. Programs, tables, maps, etc. are stored, for example, in the nonvolatile memory.

[0018] At least a part of the storage unit 16 may be provided in the above-mentioned processor, integrated circuit, etc. At least a part of the storage unit 16 may be installed in a device connected to the active sound effect generation device 10 via a network.

[0019] The signal generation unit 18 generates a sound effect signal S that causes a sound effect to be output from the speaker 12. The output unit 20 outputs the sound effect signal S generated by the signal generation unit 18 to the speaker 12. The speaker 12 generates a sound effect corresponding to the sound effect signal S inside the vehicle cabin.

[0020] 2 is a functional block diagram of the signal generation unit 18 according to one embodiment. The signal generation unit 18 includes a first single sound signal generation unit 22, a second single sound signal generation unit 24, a third single sound signal generation unit 26, a first order sound signal generation unit 28, a second order sound signal generation unit 30, a first background sound signal generation unit 32, a second background sound signal generation unit 34, a third background sound signal generation unit 36, a determination unit 38, selection switches 40a to 40h, and a synthesis unit 42.

[0021] The first single sound signal generating unit 22, the second single sound signal generating unit 24, and the third single sound signal generating unit 26 generate single sound signals, which are electrical signals that cause the speaker 12 to output a single sound that changes depending on the state of the launch control. The state of the launch control will be described in detail later.

[0022] The first sound signal generating unit 22 generates a first sound signal Sa1. The first sound signal Sa1 is a sound signal whose main component is a relatively low frequency f1. The frequency f1 corresponds to the first frequency of the present invention. A sound whose main component is the frequency f1 component means that the amplitude of the sound of frequency f1 is the largest. The selection switch 40a switches between a state (ON) in which the first sound signal Sa1 is output to the synthesis unit 42 and a state (OFF) in which the first sound signal Sa1 is not output to the synthesis unit 42. Hereinafter, the sound whose main component is the frequency f1 component may be referred to as the first sound or the first sound effect. When the launch control is in the "preparing" state, the first sound is output from the speaker 12 to the vehicle interior.

[0023] The second single sound signal generating unit 24 generates a second single sound signal Sa2. The second single sound signal Sa2 is a sound signal whose main component is a frequency f2, which is higher than frequency f1. Frequency f2 corresponds to the second frequency of the present invention. A sound whose main component is frequency f2 indicates that the amplitude of the sound at frequency f2 is the largest. The selection switch 40b switches between a state (ON) in which the second single sound signal Sa2 is output to the synthesis unit 42 and a state (OFF) in which the second single sound signal Sa2 is not output to the synthesis unit 42. Hereinafter, the sound whose main component is frequency f2 may be referred to as the second single sound or second sound effect. When the launch control is in the "ready" state, the second single sound is output from the speaker 12 to the vehicle interior.

[0024] The third single sound signal generating unit 26 generates a third single sound signal Sa3. The third single sound signal Sa3 is a sound signal whose main component is a frequency f3 component, which is different from both the frequency f1 and the frequency f2. The frequency f3 corresponds to the third frequency of the present invention. A sound whose main component is the frequency f3 component means that the amplitude of the sound of the frequency f3 is the largest. The selection switch 40c switches between a state in which the third single sound signal Sa3 is output to the synthesis unit 42 (ON) and a state in which the third single sound signal Sa3 is not output to the synthesis unit 42 (OFF). Hereinafter, the sound whose main component is the frequency f3 component may be referred to as the third single sound or the third sound effect. When the launch control is in the "active" state, the third single sound is output inside the vehicle from the speaker 12.

[0025] The first order sound signal generation unit 28 and the second order sound signal generation unit 30 generate order sound signals, which are electrical signals that cause order sounds that change in conjunction with fluctuations in the rotation speed of the electric motor to be output from the speaker 12. The first background sound signal generation unit 32, the second background sound signal generation unit 34, and the third background sound signal generation unit 36 ​​generate background sound signals, which are electrical signals that cause background sounds that are not in conjunction with fluctuations in the rotation speed of the electric motor to be output from the speaker 12. Figure 3 is an image diagram showing the frequency bands of the order sounds and the frequency bands of the background sounds.

[0026] The first-order sound signal generator 28 generates a first-order sound signal Sb1. The first-order sound signal Sb1 is a sound signal made up of a plurality of frequency components in a predetermined frequency band centered on the 24th-order frequency of the rotation speed of the electric motor.

[0027] Note that the sound consisting of multiple frequency components in a predetermined frequency band centered on the 24th frequency of the rotational speed of the electric motor means sound whose center is the 24th frequency of the rotational speed of the electric motor. Therefore, the amplitude of the sound of the 24th frequency of the rotational speed of the electric motor may be smaller than the amplitude of sounds of other frequencies.

[0028] 3, a predetermined frequency band centered on the 24th-order frequency of the rotation speed N1 [rpm] of the electric motor is shown as band A. The selection switch 40d switches between a state (ON) in which the first-order sound signal Sb1 is output to the synthesis unit 42 and a state (OFF) in which the first-order sound signal Sb1 is not output to the synthesis unit 42. Hereinafter, sound made up of multiple frequency components in a predetermined frequency band centered on the 24th-order frequency of the rotation speed of the electric motor may be referred to as first-order sound.

[0029] The second-order sound signal generating unit 30 generates a second-order sound signal Sb2. The second-order sound signal Sb2 is a sound signal made up of a plurality of frequency components in a predetermined frequency band centered on the 48th-order frequency of the rotation speed of the electric motor.

[0030] Note that the sound composed of multiple frequency components in a predetermined frequency band centered on the 48th frequency of the electric motor's rotation speed means sound whose center is the 48th frequency of the electric motor's rotation speed. Therefore, the amplitude of the sound of the 48th frequency of the electric motor's rotation speed may be smaller than the amplitude of sounds of other frequencies.

[0031] In Figure 3, a predetermined frequency band centered on the 48th-order frequency of the electric motor rotation speed N1 [rpm] is shown as band B. The selection switch 40b switches between a state (ON) in which the second-order sound signal Sb2 is output to the synthesis unit 42 and a state (OFF) in which the second-order sound signal Sb2 is not output to the synthesis unit 42. Hereinafter, a sound consisting of multiple frequency components in a predetermined frequency band centered on the 48th-order frequency of the electric motor rotation speed may be referred to as a second-order sound. Hereinafter, both the first-order sound and the second-order sound may be referred to as a fourth sound effect.

[0032] The first background sound signal generator 32 generates a first background sound signal Sc1. The first background sound signal Sc1 is a sound signal made up of a plurality of frequency components in a predetermined frequency band centered on frequency f4.

[0033] Note that a sound consisting of multiple frequency components in a predetermined frequency band centered on frequency f4 means a sound whose center frequency is frequency f4, so the amplitude of the sound at frequency f4 may be smaller than the amplitudes of sounds at other frequencies.

[0034] 3, a predetermined range of frequency band centered on frequency f4 is shown as band C. The selection switch 40f switches between a state (ON) in which the first background sound signal Sc1 is output to the synthesis unit 42 and a state (OFF) in which the first background sound signal Sc1 is not output to the synthesis unit 42. Hereinafter, sound made up of multiple frequency components in a predetermined range of frequency band centered on frequency f4 may be referred to as first background sound.

[0035] The second background sound signal generator 34 generates a second background sound signal Sc2. The second background sound signal Sc2 is a sound signal made up of a plurality of frequency components in a predetermined frequency band centered on frequency f5.

[0036] Note that a sound consisting of multiple frequency components in a predetermined frequency band centered on frequency f5 means a sound whose center frequency is frequency f5, so the amplitude of the sound at frequency f5 may be smaller than the amplitudes of sounds at other frequencies.

[0037] 3, a predetermined range of frequency band centered on frequency f5 is shown as band D. The selection switch 40g switches between a state (ON) in which the second background sound signal Sc2 is output to the synthesis unit 42 and a state (OFF) in which the second background sound signal Sc2 is not output to the synthesis unit 42. A sound made up of multiple frequency components in a predetermined range of frequency band centered on frequency f5 may be referred to as second background sound.

[0038] The third background sound signal generator 36 generates a third background sound signal Sc3. The third background sound signal Sc3 is a sound signal made up of a plurality of frequency components in a predetermined frequency band centered on frequency f6.

[0039] Note that a sound consisting of multiple frequency components in a predetermined frequency band centered on frequency f6 means a sound whose center frequency is frequency f6, so the amplitude of the sound at frequency f6 may be smaller than the amplitudes of sounds at other frequencies.

[0040] 3, a predetermined range of frequency band centered on frequency f6 is shown as band E. The selection switch 40h switches between a state (ON) in which the third background sound signal Sc3 is output to the synthesis unit 42 and a state (OFF) in which the third background sound signal Sc3 is not output to the synthesis unit 42. A sound made up of multiple frequency components in a predetermined range of frequency band centered on frequency f6 may be referred to as third background sound.

[0041] The synthesis unit 42 generates a sound effect signal S based on the first single sound signal Sa1, the second single sound signal Sa2, the third single sound signal Sa3, the first order sound signal Sb1, the second order sound signal Sb2, the first background sound signal Sc1, the second background sound signal Sc2, and the third background sound signal Sc3.

[0042] The determination unit 38 determines the state of the launch control. The state of the launch control is determined from four states: "released," "preparing," "ready," and "operating." The state of the launch control is determined based on the accelerator pedal opening, the brake pedal force, and the coolant flow rate increase completion flag. The determination of the state of the launch control will be described in detail later.

[0043] The selection switches 40a to 40h are each switched depending on the state of the launch control. By switching the selection switches 40a to 40h, the sound effect output from the speaker 12 can be changed.

[0044] [About the order sounds and background sounds] When the electric motor rotates, a sound obtained by combining the first order sound, the second order sound, the first background sound, the second background sound, and the third background sound is output as a sound effect from speaker 12 inside the vehicle. FIG. 4 is a graph showing the frequency components of the electric motor sound and the frequency components of a combined sound of the electric motor sound and the sound effect. The graph shown by the thin line in FIG. 4 shows the frequency components of the electric motor sound, and the graph shown by the thick line shows the frequency components of the combined sound. FIG. 4 shows the frequency components when the electric motor is at rotation speed N1 (see FIG. 3). Note that the electric motor sound is not limited to sound generated by the electric motor itself. The electric motor sound may also include sound generated by gears that rotate in synchronization with the electric motor.

[0045] As shown by the thin line graph in Figure 4, the sound pressure level of the 24th-order frequency component of the electric motor sound and the sound pressure level of the 48th-order frequency component of the electric motor sound are prominent compared to the sound pressure levels of other frequency components of the electric motor sound. Therefore, the 24th-order frequency component and the 48th-order frequency component sound prominent to vehicle occupants, causing discomfort to the occupants. Therefore, by generating the first-order sound and the second-order sound from speaker 12, the sound pressure level of the component in a predetermined frequency band centered on the 24th-order frequency and the sound pressure level of the component in a predetermined frequency band centered on the 48th-order frequency are increased (see the areas indicated by A and B in Figure 4). This reduces the prominentness of the 24th-order frequency component and the 48th-order frequency component, making it possible to create a synthesized sound that is linked to fluctuations in the rotation speed of the electric motor.

[0046] The order of the frequency component at which the sound pressure level is prominent varies depending on the specifications of the electric motor, the transmission, the powertrain, etc. Therefore, the order of the frequency component at which the sound pressure level is prominent is not limited to the 24th order or the 48th order. Furthermore, the number of locations at which the sound pressure level is prominent varies depending on the specifications of the electric motor, the transmission, the powertrain, etc. Therefore, the number of locations at which the sound pressure level is prominent is not limited to two (the 24th order and the 48th order). For example, if the sound pressure level is prominent at three locations, a third order sound signal generation unit (not shown) may be provided in the signal generation unit 18 in addition to the first order sound signal generation unit 28 and the second order sound signal generation unit 30 shown in FIG. 2.

[0047] Furthermore, the vehicle body may resonate with the electric motor sound, causing the sound pressure level of the vehicle body's resonant frequency component to stand out compared to the sound pressure levels of other frequency components. Therefore, by generating the first, second, and third background sounds from speaker 12, the sound pressure level of the components in a predetermined frequency band centered on the vehicle body's resonant frequency is increased (see the areas indicated by C, D, and E in FIG. 4). This makes it possible to produce a synthesized sound in which the prominence of the resonant sound is softened.

[0048] Since the resonant frequency differs depending on the vehicle body, the center frequencies of the first background sound, second background sound, and third background sound are adjusted and determined for each vehicle body. Furthermore, since the number of resonant frequencies also differs depending on the vehicle body, the number of types of background sounds is not limited to three, i.e., the first background sound, the second background sound, and the third background sound, but may be two or fewer types of background sounds, or four or more types of background sounds. For example, when there are two types of background sounds, a state in which the third background sound is not output to the synthesis unit 42 can be selected using the selection switch 40h shown in FIG. 2. For example, when there are four types of background sounds, a fourth background sound signal generation unit (not shown) may be provided in the signal generation unit 18 in addition to the first background sound signal generation unit 32, the second background sound signal generation unit 34, and the third background sound signal generation unit 36 ​​shown in FIG. 1.

[0049] When the electric motor rotates, a sound obtained by combining the first order sound and the second order sound may be output as a sound effect inside the vehicle from the speaker 12. In other words, the sound effect does not have to include background sound.

[0050] [Launch control activation sound effect] Fig. 5 is a diagram for explaining the sound effects that occur when the launch control is activated. From top to bottom, Fig. 5 shows a time chart of the brake pedal force, a time chart of the accelerator pedal opening, a time chart of the flow rate increase completion flag, a time chart of the launch control state, a time chart of the electric motor torque, and a time chart of the vehicle speed.

[0051] Launch control improves the vehicle's acceleration performance when starting off by suppressing slippage of the drive wheels while causing the electric motor to output higher-than-normal torque. When launch control is not activated, that is, under normal conditions, the torque of the electric motor when the vehicle starts is limited to limit L1. On the other hand, when launch control is activated, the torque of the electric motor when the vehicle starts is allowed up to limit L2, which is higher than limit L1. When the vehicle is stopped, the torque of the electric motor is limited to limit L3. This limit L3 is the torque limit value when the driver simultaneously depresses the brake pedal and accelerator pedal.

[0052] When the driver simultaneously depresses the brake pedal and accelerator pedal while the vehicle is stopped, launch control preparation begins. When launch control preparation begins, the flow rate of coolant that cools the electric motor is increased above normal. While launch control is activated, the electric motor generates more torque than normal, resulting in greater heat generation. Therefore, the flow rate of coolant is increased to improve the electric motor's cooling performance. Once the increase in the coolant flow rate is complete, the flow rate increase completion flag switches from "0" to "1." After that, when the driver releases his or her foot on the brake pedal, launch control is activated and the vehicle starts moving. When launch control is activated, the electric motor can generate higher-than-normal torque, improving acceleration performance when starting compared to normal times when launch control is not activated.

[0053] When the brake pedal force is equal to or greater than the threshold Bth1 and the accelerator pedal opening is equal to or greater than the threshold Ath, the determination unit 38 determines that the state of launch control is "preparing." If the brake pedal force is less than the threshold Bth1 or the accelerator pedal opening is less than the threshold Ath, the determination unit 38 determines that the state of launch control is "released."

[0054] When the flow rate increase completion flag becomes "1" while the brake pedal force is equal to or greater than threshold value Bth1 and the accelerator pedal opening is equal to or greater than threshold value Ath, determination unit 38 determines that the state of launch control is "ready." If the brake pedal force becomes equal to or less than threshold value Bth2 after "ready," determination unit 38 determines that the state of launch control is "active." When a predetermined time has elapsed since the state of launch control was determined to be "active," determination unit 38 determines that the state of launch control is "released."

[0055] When it is determined that the launch control state is "preparing," a first single sound (first sound effect) is output from the speaker 12. The first single sound is a sound that mainly contains a relatively low frequency component f1. This allows the driver to feel an increase in torque.

[0056] If the launch control state is determined to be "ready," a second single sound (second sound effect) is output from speaker 12. The second single sound is a sound whose main component is frequency f2, which is higher than frequency f1. Switching from the first sound effect to the second sound effect makes the driver aware that launch control preparation is complete and that the vehicle can start with high acceleration by simply releasing the brakes. In addition, by outputting a sound with a relatively high frequency from speaker 12, it is possible to simulate a state in which the engine speed is maintained at a high level in an internal combustion engine vehicle.

[0057] If it is determined that the state of the launch control is "operating", a third single sound (third sound effect) is output from the speaker 12. When the state of the launch control is "operating", the electric motor is rotating, and therefore the order sound (fourth sound effect) and background sound are output from the speaker 12. In other words, a synthesized sound of the third single sound, the order sound, and the background sound is output from the speaker 12. Hereinafter, the synthesized sound of the third single sound, the order sound, and the background sound may be referred to as a fifth sound effect.

[0058] As a result, in addition to the order sounds and background sounds that are normally output, a synthesized sound synthesized with the third single sound is output from speaker 12, which makes it possible for the driver to recognize that acceleration that is different from normal is occurring. For example, by setting the frequency f3 of the sound that is the main component of the third single sound to a value close to the frequency of the wind noise of the vehicle, it is possible to give the driver a sense of acceleration.

[0059] [Configuration of the single tone signal generator] 6 is a functional block diagram showing the first sound signal generating section 22 according to one embodiment. The first sound signal generating section 22 includes a reference signal setting section 44, a gain setting section 46, and a correction section 48.

[0060] The reference signal setting unit 44 sets the reference signal SA1. The reference signal SA1 is a sound signal having a component of frequency f1 as a main component.

[0061] The gain setting unit 46 sets the gain Ga. The gain Ga is set in accordance with the rotation speed of the electric motor, the output of the electric motor, the torque of the electric motor, the accelerator pedal opening, and the acceleration / deceleration of the vehicle.

[0062] The correction unit 48 multiplies the reference signal SA1 set by the reference signal setting unit 44 by the gain Ga to obtain a first One-off Sound signal S a Outputs 1.

[0063] The second single sound signal generating unit 24 differs from the first single sound signal generating unit 22 in that the reference signal set by the reference signal setting unit 44 is a sound signal having a frequency f2 component as its main component, but other configurations are the same as those of the first single sound signal generating unit 22.

[0064] The third single sound signal generating unit 26 differs from the first single sound signal generating unit 22 in that the reference signal set by the reference signal setting unit 44 is a sound signal having a frequency f3 component as its main component, but other configurations are the same as those of the first single sound signal generating unit 22.

[0065] [Configuration of the order sound signal generator] 7 is a functional block diagram showing the first-order sound signal generation unit 28 in one embodiment. The first-order sound signal generation unit 28 has a reference signal setting unit 50, a gain setting unit 52, and a correction unit 54.

[0066] The reference signal setting unit 50 sets the reference signal SB1 based on the rotation speed of the electric motor. The reference signal SB1 is a sound signal made up of multiple frequency components in a predetermined frequency band centered on the 24th order frequency of the rotation speed of the electric motor.

[0067] The gain setting unit 52 sets the gain Gb. The gain Gb is set in accordance with the rotation speed of the electric motor, the output of the electric motor, the torque of the electric motor, the accelerator pedal opening, and the acceleration / deceleration of the vehicle.

[0068] The correction unit 54 multiplies the reference signal SB1 set by the reference signal setting unit 50 by a gain Gb to obtain a first-order sound signal Sb1, and outputs the resultant signal.

[0069] The second-order sound signal generation unit 30 differs from the first-order sound signal generation unit 28 in that the reference signal set by the reference signal setting unit 50 is a sound signal consisting of multiple frequency components in a predetermined frequency band centered on the 48th frequency of the rotation speed of the electric motor. However, the other configurations of the second-order sound signal generation unit 30 are the same as those of the first-order sound signal generation unit 28.

[0070] [Configuration of background sound signal generation unit] 8 is a functional block diagram showing the first background sound signal generation unit 32 according to one embodiment. The first background sound signal generation unit 32 includes a reference signal setting unit 56, a gain setting unit 58, and a correction unit 60.

[0071] The reference signal setting unit 56 sets the reference signal SC1. The reference signal SC1 is a sound signal made up of a plurality of frequency components in a frequency band whose center frequency is frequency f4.

[0072] The gain setting unit 58 sets the gain Gc according to the rotation speed of the electric motor, the output of the electric motor, the torque of the electric motor, the accelerator pedal opening, and the acceleration / deceleration of the vehicle.

[0073] The correction unit 60 outputs the first background sound signal Sc1 obtained by multiplying the reference signal SC1 set by the reference signal setting unit 56 by the gain Gc.

[0074] The second background sound signal generation unit 34 differs from the first background sound signal generation unit 32 in that the reference signal set by the reference signal setting unit 56 is a sound signal made up of multiple frequency components in a frequency band whose center frequency is frequency f5. However, the other configurations of the second background sound signal generation unit 34 are the same as those of the first background sound signal generation unit 32.

[0075] The third background sound signal generation unit 36 ​​differs from the first background sound signal generation unit 32 in that the reference signal set by the reference signal setting unit 56 is a sound signal made up of multiple frequency components in a frequency band whose center frequency is frequency f6. However, the other configurations of the third background sound signal generation unit 36 ​​are the same as those of the first background sound signal generation unit 32.

[0076] [Sound effect generation processing] 9 is a flowchart of the sound effect generation process performed by the active sound effect generation device 10 in this embodiment. The sound effect generation process is repeatedly executed at a predetermined cycle while the vehicle is running.

[0077] In step S1, the determination unit 38 determines whether or not an operation to activate the launch control has been received. The operation to activate the launch control refers to the driver simultaneously depressing the brake pedal and the accelerator pedal.

[0078] In step S1, if it is determined that an operation to activate the launch control has been received (step S1: YES), the process proceeds to step S2. In step S2, the determination unit 38 determines whether the state of the launch control is "preparing."

[0079] If it is determined in step S2 that the state of the launch control is "preparing" (step S2: YES), the process proceeds to step S3. In step S3, the determination unit 38 turns the selection switch 40a "ON" and turns each of the selection switches 40b to 40h "OFF." As a result, only the first single sound signal Sa1 is input to the synthesis unit 42, and the synthesis unit 42 generates a sound effect signal S that is the same as the first single sound signal Sa1. In other words, a sound effect signal S that causes the first single sound (first sound effect) to be output from the speaker 12 is generated. After that, the process proceeds to step S9.

[0080] In step S2, if it is determined that the state of the launch control is not "preparing" (step S2: NO), the process proceeds to step S4. In step S4, the determination unit 38 determines whether the state of the launch control is "ready".

[0081] If it is determined in step S4 that the state of the launch control is "ready" (step S4: YES), the process proceeds to step S5. In step S5, the determination unit 38 turns the selection switch 40b "ON" and turns each of the selection switches 40a, 40c to 40h "OFF." As a result, only the second single sound signal Sa2 is input to the synthesis unit 42, and the synthesis unit 42 generates a sound effect signal S that is the same as the second single sound signal Sa2. In other words, a sound effect signal S that causes the speaker 12 to output the second single sound (second sound effect) is generated. After that, the process proceeds to step S9.

[0082] In step S4, if it is determined that the state of the launch control is not "ready" (step S4: NO), the process proceeds to step S6. In step S6, the determination unit 38 determines whether the state of the launch control is "operating".

[0083] If it is determined in step S6 that the state of the launch control is "active" (step S6: YES), the process proceeds to step S7. In step S7, the determination unit 38 turns each of the selection switches 40c to 40h "ON" and turns each of the selection switches 40a and 40b "OFF." As a result, the third single sound signal Sa3, the first-order sound signal Sb1, the second-order sound signal Sb2, the first background sound signal Sc1, the second background sound signal Sc2, and the third background sound signal Sc3 are input to the synthesis unit 42. The synthesis unit 42 generates a sound effect signal S, which is a signal obtained by synthesizing the third single sound signal Sa3, the first-order sound signal Sb1, the second-order sound signal Sb2, the first background sound signal Sc1, the second background sound signal Sc2, and the third background sound signal Sc3. That is, a sound effect signal S is generated that causes a synthesized sound (fifth sound effect) of the third single sound, the first order numeric sound, the second order numeric sound, the first background sound, the second background sound, and the third background sound to be output from the speaker 12. Then, the process proceeds to step S9.

[0084] If it is determined in step S1 that an operation to activate the launch control has not been received (step S1: NO), the process proceeds to step S8. Also, if it is determined in step S6 that the state of the launch control is not "activated" (step S6: NO), the process proceeds to step S8.

[0085] In step S8, the determination unit 38 turns each of the selection switches 40d to 40h "ON" and turns each of the selection switches 40a to 40c "OFF." As a result, the first order sound signal Sb1, the second order sound signal Sb2, the first background sound signal Sc1, the second background sound signal Sc2, and the third background sound signal Sc3 are input to the synthesis unit 42. The synthesis unit 42 generates a sound effect signal S that is a signal obtained by synthesizing the first order sound signal Sb1, the second order sound signal Sb2, the first background sound signal Sc1, the second background sound signal Sc2, and the third background sound signal Sc3. In other words, a sound effect signal S is generated that causes the speaker 12 to output a synthesized sound of the first order sound, the second order sound, the first background sound, the second background sound, and the third background sound. Then, the process proceeds to step S9.

[0086] In step S9, the output unit 20 outputs the sound effect signal S to the speaker 12. As a result, the sound effect is output to the vehicle interior from the speaker 12. Thereafter, the sound effect generation process ends.

[0087] The following additional notes are further disclosed regarding the above embodiment.

[0088] (Appendix 1) The active sound effect generating device (10) disclosed herein is an active sound effect generating device that causes a speaker (12) to output a sound effect toward the interior of a vehicle driven by a drive source, and includes a determination unit (38) that determines whether or not the launch control is in preparation when an operation to activate launch control that improves acceleration performance when the vehicle starts is received, a signal generation unit (18) that generates a sound effect signal that is a signal that causes the speaker to output the sound effect, and an output unit (20) that outputs the sound effect signal generated by the signal generation unit to the speaker, and when it is determined by the determination unit that the launch control is in preparation, the signal generation unit generates the sound effect signal that causes the speaker to output a first sound effect that has a first frequency component as its main component.

[0089] (Appendix 2) In the active sound effect generating device described in Supplementary Note 1, the determination unit may further determine whether or not preparation for the launch control has been completed, and when the determination unit determines that preparation for the launch control has been completed, the signal generation unit may generate the sound effect signal that causes the speaker to output a second sound effect having, as a main component, a component of a second frequency that is higher than the first frequency.

[0090] (Appendix 3) In the active sound effect generation device described in Supplementary Note 2, the determination unit may further determine whether or not the launch control is in operation, and when the determination unit determines that the launch control is in operation, the signal generation unit may generate the sound effect signal that causes the speaker to output a third sound effect having, as a main component, a component of a third frequency that is different from both the first frequency and the second frequency.

[0091] (Appendix 4) In the active sound effect generation device described in Supplementary Note 2, the determination unit may further determine whether the launch control is in operation, and when the determination unit determines that the launch control is in operation, the signal generation unit may generate the sound effect signal that causes the speaker to output a fifth sound effect that is a combination of a third sound effect having, as a main component, a component of a third frequency that is different from both the first frequency and the second frequency, and a fourth sound effect that changes in accordance with the rotation speed of the drive source.

[0092] (Appendix 5) The active sound effect generation method disclosed herein is an active sound effect generation method for outputting sound effects from a speaker toward the interior of a vehicle driven by a drive source, and includes the following steps when an operation to activate launch control that improves acceleration performance when the vehicle starts is received: a determination step for determining whether the launch control is in preparation; a signal generation step for generating a sound effect signal that is a signal for outputting the sound effect from the speaker; and an output step for outputting the sound effect signal generated in the signal generation step to the speaker; and if it is determined in the determination step that the launch control is in preparation, the signal generation step generates the sound effect signal that causes the speaker to output a first sound effect that has a first frequency component as its main component.

[0093] Although the present disclosure has been described in detail, the present disclosure is not limited to the individual embodiments described above. Various additions, substitutions, modifications, partial deletions, etc. are possible in these embodiments without departing from the gist of the present disclosure or the spirit of the present disclosure derived from the content of the claims and their equivalents. These embodiments can also be implemented in combination. For example, in the above-described embodiments, the order of each operation and the order of each process are shown as examples and are not limited to these. The same applies when numerical values ​​or mathematical expressions are used in the description of the above-described embodiments. [Explanation of symbols]

[0094] 10...Active sound effect generator 12...Speaker 18... signal generating section 20... output section 38…Judgment section

Claims

1. An active sound effect generating device that outputs sound effects from a speaker toward a vehicle interior of a vehicle driven by a drive source, a determination unit that, when an operation to activate a launch control that improves acceleration performance when the vehicle starts is received, determines whether the launch control is in preparation; a signal generating unit that generates a sound effect signal that causes the speaker to output the sound effect; an output unit that outputs the sound effect signal generated by the signal generation unit to the speaker; Equipped with when the determination unit determines that the launch control is being prepared, the signal generation unit generates the sound effect signal that causes the speaker to output a first sound effect having a component of a first frequency as a main component; The determination unit further determines whether or not preparation for the launch control has been completed, When the determination unit determines that preparation for the launch control is complete, the signal generation unit generates the sound effect signal that causes the speaker to output a second sound effect having, as its main component, a component of a second frequency that is higher than the first frequency.

2. 2. The active sound effect generating device according to claim 1, The determination unit further determines whether the launch control is in operation, When the determination unit determines that the launch control is operating, the signal generation unit generates the sound effect signal that causes the speaker to output a third sound effect having, as a main component, a component of a third frequency that is different from both the first frequency and the second frequency.

3. 2. The active sound effect generating device according to claim 1, The determination unit further determines whether the launch control is in operation, When the determination unit determines that the launch control is operating, the signal generation unit generates the sound effect signal that causes the speaker to output a fifth sound effect that is a combination of a third sound effect having, as its main component, a component of a third frequency that is different from both the first frequency and the second frequency, and a fourth sound effect that changes depending on the rotation speed of the drive source.

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