JP6327167B2 - Sound effect generator for vehicles - Google Patents

Description

  The present invention relates to a vehicle sound effect generating device, and more particularly to a vehicle sound effect generating device that adds a vibration sound of a predetermined component to a sound effect when the vehicle is turning.

In recent years, the quietness of vehicle interiors has been dramatically promoted in terms of both vehicle body structure and control. As a result, a situation has arisen in which it is not possible to appropriately obtain a sense of driving sensation due to engine sound.
Therefore, a sound effect generator (also referred to as Active Engine Sound) that detects the amount of driving operation performed by the driver and generates a sound effect corresponding to the driving operation amount in the vehicle interior through a vehicle interior speaker has been proposed.

The sound effect generator disclosed in Patent Document 1 includes a fundamental frequency setting unit that sets a fundamental frequency corresponding to the engine speed, a harmonic determination unit that determines a plurality of harmonics of the fundamental frequency, and a harmonic enhancement gain of the engine. A gain determining means for determining, the gain determining means including a circuit for determining an engine load, the engine load determining circuit comprising: an accelerator pedal position determining circuit; an intake air amount determining circuit; a negative pressure determining circuit; an engine torque determining circuit; A configuration including at least one and adjusting the harmonic enhancement level based on the harmonic enhancement gain is disclosed.
As a result, an occupant including the driver can experience an exciting level of engine sound.

Special table 2014-507679

With the sound effect generator of Patent Document 1, it is possible to intentionally reproduce different engine features depending on the force of the engine sound of the actual vehicle and the vehicle type.
However, since the sound effect generator of Patent Document 1 determines the harmonic emphasis gain by the engine load determination circuit, it cannot obtain a sufficient sense of realism that matches the running state in the following points. There is a possibility that driving information by hearing, which is one of the information necessary for the driving operation, cannot be obtained.

In general, the driving behavior of a vehicle includes a turning state by a steering wheel (hereinafter abbreviated as steering) operation in addition to an acceleration state, a constant speed state, and a deceleration state by a driver's accelerator operation.
In the initial turning state, if the accelerator is excessively depressed, the ground frictional force of the front wheels loses the centrifugal force and tends to understeer, and it is necessary to return the accelerator and / or add the steering. Because of the opening, almost no harmonic emphasis gain is generated. Therefore, since the driving information (sound effect) perceived by the driver's hearing is small, there is a concern that the start timing of the response by the driver may be delayed.

In the middle of the turning state, theoretically, a harmonic emphasis gain is hardly generated because it is a so-called partial state in which the accelerator is held at a small opening. Therefore, despite the presence of a large cornering force, the driving information perceived by the driver's hearing is insufficient, and there is a risk of feeling uncomfortable.
Also, in the latter half of the turning state, when the accelerator is depressed while turning back the steering, even though the cornering force is gradually decreasing, the harmonic emphasis gain almost occurs in the region where the accelerator is still not sufficiently open. Not. Therefore, the driver cannot expect an increase in vehicle speed when the accelerator is depressed at the corner exit.

  An object of the present invention is to provide a vehicle sound effect generating device and the like that can enhance a sense of presence in a vehicle turning state by providing driving information via hearing to a driver.

According to the first aspect of the present invention, the engine speed detecting means, the accelerator opening degree detecting means, and the gains of a plurality of integer components of the engine speed are set based on the accelerator opening degree detected by the accelerator opening degree detecting means. Turning condition determination for determining a turning state of a vehicle in a gain setting means and a vehicle sound effect generating device for generating a sound effect based on a gain set by the gain setting means and a vibration sound database of the plurality of integer components And when the vehicle is in a turning state, a gain of a low-order component of the plurality of integer order components is set to be larger than a gain of the low-order component in a state other than the turning state, and the vehicle turns When the accelerator opening is small, the gain increase rate of the lower order component of the plurality of integer order components is set to be larger than the gain increase rate of the middle and higher order components. When the vehicle and the accelerator opening is large in a turning state, is characterized by a gain increase rate of the low-order component of the plurality of fractional component is set smaller than the gain increase rate of medium to high order components .

Since the vehicle sound effect generating device includes the turning state determining means for determining the turning state of the vehicle, the turning state of the vehicle including the entrance and the exit of the corner can be accurately determined.
When the vehicle is in a turning state, the gain of the low-order component of the plurality of integer order components is set to a larger value than the gain of the low-order component in a case other than the turning state, and the vehicle is in the turning state and the accelerator When the opening is small, the gain increase rate of the low order component of the plurality of integer order components is set larger than the gain increase rate of the medium and high order components, and when the vehicle is turning and the accelerator opening is large, Since the gain increase rate of the low-order component of the plurality of integer order components is set smaller than the gain increase rate of the medium-high order component, the driving information perceived by the driver's hearing can be increased, and the driver Can be resolved.
Moreover, since the driver can perceive the feeling of the accelerator operation sensitively, the accelerator operation in the partial state can be audibly supported while suppressing excessive depression of the accelerator.

  According to the vehicle sound effect generating device of the present invention, it is possible to increase the presence of the vehicle turning state by providing the driver with driving information through hearing.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram of a vehicle equipped with a vehicle sound effect generating device according to a first embodiment. It is a block diagram of the sound effect generator for vehicles. It is a vibration sound map. It is a basic order component map set for each engine speed. It is a turning order component map set by the accelerator opening and the gain. It is a turning half order component map set up with accelerator opening and gain. This is a steering force characteristic set by the steering torque and the yaw rate. It is explanatory drawing of the 1st attention running state. It is an example of a time chart when turning around a corner.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The following description exemplifies a case where the present invention is applied to the vehicle V, and does not limit the present invention, its application, or its use.

Embodiment 1 of the present invention will be described below with reference to FIGS.
The sound effect generating device 1 provides driving information via hearing to the driver by generating sound effects of the engine according to the turning state of the vehicle V, and enhances the production effect during driving.
As shown in FIGS. 1 and 2, the sound effect generator 1 includes an ECU (Electric Control Unit) 2, a rotational speed sensor 3 that can detect the engine rotational speed, and an accelerator that can detect the accelerator opening (%). An opening sensor 4, a brake switch 5 that can detect depression of a brake pedal, a steering angle sensor 6 that can detect a steering angle amount of a steering wheel (hereinafter abbreviated as steering), and a stable running state of the vehicle V A turning control device (hereinafter abbreviated as DSC device) 7 and a pair of speakers 8 disposed in the left and right end regions of the passenger compartment.
The sound effect generating device 1 is configured to be able to execute an effect function, a corner escape notice function, a warning function, and the like by an engine sound effect.

First, the ECU 2 will be described.
The ECU 2 includes a CPU (Central Processing Unit), a ROM, a RAM, an amplifier, an in-side interface, an out-side interface, and the like.
Various programs and data for generating engine sound effects are stored in the ROM, and a processing area used when the CPU performs a series of processes is provided in the RAM.
The in-side interface is electrically connected to each of the sensors 3 to 6 and the DSC device 7, and the out-side interface is electrically connected to a pair of speakers 7 via an amplifier.

The ECU 2 includes a storage unit 11 (vibration sound database), a traveling state determination unit 12 (turning state determination unit), a gain setting unit 13, a sound effect generation unit 14, and the like.
The storage unit 11 includes a vibration sound map M1, a normal ordering component map M2, a turning ordering component map M3, and a turning half order component that are set in advance so as to match the sound generated by the engine mounted on the vehicle V. A map M4 and a steering force characteristic M5 are stored.

As shown in FIG. 3, the vibration sound map M1 includes a fundamental sound source having a fundamental frequency component corresponding to a predetermined engine speed, and integer order frequency components 4, 6, and 8 times the fundamental sound. A sound source of 4th, 6th and 8th order component wave (harmonic) sound, and a sound source of 3.5, 5.5th order component wave sound having a half order frequency component of 3.5, 5.5 times the fundamental wave sound It is provided for each engine speed.
Basically, the integer component wave sound is an easy-to-understand harmonic sound that stretches, and makes the driver perceive a light movement feeling. The semi-order component wave sound is an unpleasant rumble sound such as a booming sound or cracking sound, and makes the driver perceive a sense of power accompanied by a sense of vigilance.
In the present embodiment, the fourth-order component sound is a low-order component sound, the sixth-order sound is a medium-order sound, and the sound exceeding the sixth-order sound is a high-order sound. High order component wave pitch is a high frequency range sound.

In the normal order component map M2, sound pressure levels (gain (%)) of the fourth, sixth, and eighth-order component sounds corresponding to the accelerator opening in the traveling state other than the turning traveling state are set.
As shown in FIG. 4, the gains a1, a2, and a3 of the fourth, sixth, and eighth-order component sounds are suppressed to a constant low gain G1, for example, 10% until the accelerator opening A1, After the gains a2 and a3 of the eighth-order component sound rise, and after a slight delay, the gain a1 of the fourth-order component sound rises with the same increasing trend as the gains a2 and a3 of the sixth-order component sound, and then the accelerator is opened. At degree A5, the gain G3 converges to the gains a2 and a3 of the 6th and 8th order component sound waves. In the following description, the accelerator opening degree satisfies the relational expression of A1 <A2 <A3 <A4 <A5 <A6, and the gain satisfies the relational expression of G1 <G2 <G3 <G4 <G5. .

In the turn order component map M3, gains b1, b2, and b3 of fourth, sixth, and eighth order component wave sounds corresponding to the accelerator opening degree in the turning state of the vehicle V are set.
As shown in FIG. 5, the gain b1 of the quaternary component wave sound increases in a proportional function, reaches a high gain G4, for example, 89% at the accelerator opening A2, and gradually decreases at the accelerator opening A2 or more. doing.
The gains b2 and b3 of the 6th and 8th order component wave sounds reach a gain G2 which is an intermediate value at the accelerator opening A3, for example, 50%, and change substantially flat in the section of the accelerator opening A3 to A4. At a degree of A4 or more, it increases and converges to a gain b1 of the fourth-order component sound with a gain G3 at the accelerator opening A5.

In the turning half-order component map M4, gains c1 and c2 of 3.5 and 5.5th order component wave sounds with respect to the accelerator opening in the turning state are set.
As shown in FIG. 6, the gain of the 3.5th and 5.5th order component wave sounds increases in a proportional function until the accelerator opening A6, and the gains c1 and c2 increase up to A6 at the accelerator opening A6 or more. An increasing trend is set to be larger than the trend.
The accelerator opening A6 is set for each corner turning radius, and is set to the upper limit opening recommended from the viewpoint of traveling safety of the vehicle V.

As shown in FIG. 7, the steering force characteristic M5 defines a correlation between the steering torque and the yaw rate.
This steering force characteristic M5 is defined by a plurality of specific factors such as a reaction force to the driver and a size of hiss generated at a predetermined steering angle, and the traveling characteristic suitable for the product concept of the vehicle V is obtained by the steering operation. It is set to be feasible.
In the steering force characteristic M5, the yaw rate increases as a quadratic function by turning the steering, and the steering torque decreases when the steering is held at a predetermined steering angle (constant yaw rate). The yaw rate is reduced to a quadratic function by turning back the steering.

Next, the traveling state determination unit 12 will be described.
The traveling state determination unit 12 determines the current turning traveling state of the vehicle V.
The turning state is determined by detecting the steering angle corresponding to the steering torque when the driver consciously turns the steering wheel, for example, 2.0 Nm, and by detecting the neutral state of the steering (neutral). The end of the turning traveling state is determined.
In addition, since there are steering addition and return operations during turning, in this embodiment, after detecting the neutral state of the steering, the turning state is detected by detecting that the neutral state is maintained for a predetermined time (for example, 2 to 3 seconds). End is judged.
The acceleration, constant speed, and decelerating straight traveling states other than the turning traveling state are determined as the normal traveling state. In basic steady running, a normal running state and a turning running state are executed.

Moreover, the traveling state determination unit 12 determines a sports traveling state, a cruise traveling state, and first and second caution traveling states as specific traveling states other than the basic steady traveling state.
The sports running state is determined by an ON operation of a sports running setting switch (not shown). In the sport running state, the damping characteristic of the damper (not shown) is set higher than normal, and the shift-up rotation speed of the automatic transmission (not shown) is set higher than normal.
The cruise traveling state is determined by an ON operation of a cruise traveling setting switch (not shown). In the cruise traveling state, the vehicle speed is kept constant, and the damping characteristic of the damper (not shown) is set lower than normal.

The first caution driving state is determined based on information such as the road surface μ from the DSC device 7.
As shown in FIG. 8, a specific friction circle is formed on each wheel according to the running state of the vehicle V. When the vehicle V is stationary, the grip point of the wheel is at the position Pa, and the vehicle V slips. In this case, the grip point is present at a position Pb outside the limit area B.
Therefore, when the grip point exceeds the determination area C set inside the limit area B as in the position Pc, it is determined that the vehicle is in the first caution driving state.
The second caution driving state is a turning driving state and is determined based on the accelerator opening speed.
When the vehicle is in a turning state and the accelerator opening speed is equal to or higher than a predetermined value, the accelerator may be excessively depressed.
When the accelerator is excessively depressed, the ground frictional force of the front wheels loses the centrifugal force and tends to understeer, and it is necessary to take measures by returning the accelerator and / or adding the steering.
Therefore, when the vehicle is turning and the accelerator opening speed is equal to or higher than a predetermined value, it is determined that the vehicle is in the second caution driving state.
In addition, it can replace with an accelerator opening speed, and can also determine a 2nd caution driving | running state with an accelerator opening. In this case, an accelerator opening value that tends to cause an understeer tendency is set according to the traveling state of the vehicle V. When the accelerator opening value is equal to or greater than the accelerator opening value, the second caution traveling state is determined.

Next, the gain setting unit 13 will be described.
The gain setting unit 12 selects a map to be used according to the determined traveling state, and sets gains a1 to a3, b1 to b3, c1 and c2 of each component wave sound with reference to the selected map. ing.
In the normal traveling state, the normal ordering component map M2 is selected, and the gains a1, a2, and a3 of the fourth, sixth, and eighth order component sounds corresponding to the accelerator opening are determined from the normal ordering component map M2.

  When the vehicle is in a turning state, the turn order component map M3 and the turn half order component map M4 are selected, and the turn order component map is obtained by using the gains b1, b2, and b3 of the fourth, sixth, and eighth order wave sounds corresponding to the accelerator opening. The gains c1 and c2 of the 3.5 and 5.5th order component sound corresponding to the accelerator opening are determined from the turning half order component map M4.

Further, the gain setting unit 12 sets correction values k1 to k4 for the gains c1 and c2 of the 3.5 and 5.5th order component wave sounds according to the determined specific traveling state.
In the sport running state, a correction value k1 (1 ≦ k1) is set to increase the gains c1 and c2 of the 3.5th and 5.5th order component wave sounds in order to enhance the driver's feeling of movement.
In the cruise driving state, a correction value k2 (0 ≦ k2 ≦ 1) for reducing the gains c1 and c2 of the 3.5 and 5.5th order component sound is set to reduce the driver's feeling of movement. Yes.
In the first caution driving state, a correction value k3 (1 ≦ k3) for increasing the gains c1 and c2 of the 3.5 and 5.5th order component sound is set in order to increase the driver's alertness. .
In the second caution driving state, a correction value k4 (1 ≦ k4) for increasing the gains c1 and c2 of the 3.5th and 5.5th order component sound is set in order to increase the driver's alertness. .

Next, the sound effect generator 14 will be described.
The sound effect generation unit 14 is configured to be able to execute a low-order component addition function, a high-order component addition function, and a half-order component addition function. The sound effect generation unit 14 generates a sound effect signal in which each of the next component wave sounds according to the running state is added to the fundamental wave sound according to the running engine speed, and is output to the pair of left and right speakers 8. doing.

  In the normal running state, the fourth-order component sound of the map M1 is multiplied by the gain a1, the sixth-order component sound of the map M1 is multiplied by the gain a2, and the eighth-order component sound of the map M1 is multiplied by the gain a3. Thus, the corrected 4th, 6th, and 8th order component sound waves are created, and the corrected 4th, 6th, and 8th order component sound waves are added to the fundamental sound, thereby generating the sound effect in the normal running state.

When the vehicle V is turning, the fourth-order component sound of the map M1 is multiplied by the gain b1, the sixth-order component sound of the map M1 is multiplied by the gain b2, and the eighth-order component sound of the map M1 and the gain b3 are multiplied. To create corrected fourth, sixth, and eighth-order component sounds, and add these corrected fourth, sixth, and eighth-order component sounds to the fundamental sound. Then, the 3.5th-order component sound of the map M1 is multiplied by the gain c1, and the 5.5th-order component sound of the map M1 and the gain c2 are multiplied to obtain the corrected 3.5th and 5.5th-order component sound. The sound effects of the turning running state are generated by adding the generated 3.5 and 5.5th order component wave sounds to the fundamental wave sound in which the 4th, 6th and 8th order component wave sounds are added.

In the sport running state or the cruise running state, the gains c1 and c2 are previously multiplied by the correction value k1 or k2, and then corrected 3.5 and 5.5th order component wave sounds are created.
In the first and second caution driving states, the gains c1 and c2 (or the corrected gains c1 and c2 when correction by the correction value k1 or k2 is necessary) are previously multiplied by the correction values k3 and k4, and then corrected. 3.5 and 5.5 order component wave sounds are created. Then, the gains of the fourth, sixth, and eighth-order component sounds are decreased so as to correspond to the increase of the 3.5, 5.5th-order component sounds so that the sound pressure level is maintained constant. As a result, the rumble sound can be relatively emphasized while keeping the sound pressure of the sound effect constant, so that the driver's alertness can be enhanced auditorily.

The operation process of the sound effect generator 1 will be described based on the time chart of FIG.
As shown in FIG. 9, when the brake is stepped on at the time of entering the corner (t0), the accelerator opening is fully closed, and the vehicle speed rapidly decreases.
Since the vehicle speed is sufficiently decelerated from the time t1, the driver starts the steering operation. The yaw rate acts on the vehicle V as the steering increases. Sound effects from before entering the corner to t2 when the steering torque becomes 2.0 Nm are generated by the fourth, sixth, and eighth order component sound corrected by the gains a1, a2, and a3 and the fundamental sound.

From the time point t2, the sound effects are the fourth, sixth and eighth order component wave sounds corrected by the gains b1, b2 and b3, the 3.5th and 5.5th order component wave sounds corrected by the gains c1 and c2, and the basic sound. Created by with sound waves. The driver perceives the quaternary component sound from the beginning of the corner entry, thereby recognizing the corner entry by hearing and avoiding the uncomfortable feeling before and after entering the corner.
When the accelerator opening speed is equal to or higher than a predetermined value (second attention running state) (t3), the 3.5th and 5.5th order component sound is increased and corrected by the correction value k4. The driver is audibly aware of the 3.5, 5.5th order component wave sound, and is alerted to excessive accelerator depression, and returns the accelerator at time t4.

At time t5, the driver decelerates and adds steering to start an understeer tendency correcting operation.
Similarly, when the first caution driving state is determined, the driver can be alerted because the 3.5th and 5.5th order component wave sounds can be perceptually perceived.
The driver recognizes the corner exit and starts the steering switchback operation from time t6, which is the latter half of the turning traveling state .
At time t7, the steering is operated to the neutral state, and the accelerator opening is gradually increased. After this time , the gain b1 of the fourth-order component sound is decreased and the gains b2 and b3 of the sixth-order and eighth-order component sounds are increased, so that the driver's acceleration feeling increases.
From time t8 after a predetermined time has elapsed from the neutral state, the sound effect is generated by the fourth, sixth, and eighth-order component sound corrected by the gains a1, a2, and a3 and the fundamental sound.

Next, operations and effects of the vehicle sound effect generating device will be described.
According to the sound effect generating device 1, since the traveling state determination unit 12 that determines the turning state of the vehicle V is provided, the turning state of the vehicle V including the entrance and the exit of the corner can be accurately determined.
When the vehicle V is in the turning traveling state, the gain b1 of the quaternary component, which is the lower order component of the plurality of integer components, is set to a larger value than the gain of the quaternary component a1 in the normal traveling state. The driving information perceived by the driver's hearing can be increased, and the driver's discomfort can be eliminated.

  When the vehicle V is in the late turn state, vibration sounds of 6th and 8th order components, which are middle and high order components among a plurality of integer order components, are added to the sound effects. As a result, since the latter half of the turning state is notified by sound effects, the driver can expect a sense of vehicle speed to increase when the accelerator is depressed at the corner exit.

  When the accelerator opening is small, the gain increase rate of the 4th order component of the plurality of integer components is set larger than the gain increase rate of the 6th and 8th components, and when the accelerator opening is large, the plurality of integer orders Among the components, the gain increase rate of the fourth order component is set smaller than the gain increase rate of the sixth and eighth order components. As a result, the driver can perceive the feeling of operation of the accelerator sensitively, so that the accelerator operation in the partial state can be audibly supported while suppressing excessive depression of the accelerator.

Next, a modified example in which the embodiment is partially changed will be described.
1) In the above embodiment, an example in which the gain of each component wave sound is set using the accelerator opening as a parameter has been described, but the gain of each component wave sound may be set using the accelerator depression amount as a parameter instead of the accelerator opening. good. Moreover, although the example which provided the sensor for exclusive use about the depression operation of a brake pedal, an accelerator opening degree, and a steering angle amount was demonstrated, each value can also be acquired from a DSC apparatus.

2] In the above embodiment, each component wave sound itself is stored as a sound source. However, each component wave sound is stored by storing each timbre signal of each component wave sound, and converting and synthesizing these timbre signals. It may be generated.

3) In the above-described embodiment, the example in which the target steering force characteristic is set based on the correlation between the steering torque and the yaw rate has been described. However, since the steering angle amount and the yaw rate are proportional to each other, the steering angle amount of the steering and the steering The target steering force characteristic may be set according to the correlation with the torque.

4] In the above embodiment, an example in which integer order frequency components that are 4, 6, and 8 times the fundamental wave sound are used has been described. However, other integer order frequency components may be used. You may use a component wave sound one by one. It is also possible to use only a single integer order frequency component, for example, a fourth order frequency component. When only a single integer order frequency component is used, the sound pressure level gradually increases from the vicinity of the corner exit. It is preferable to increase the driver's sense of presence.
Moreover, although the example which made the gain of the 6th order component wave sound and the gain of the 8th order component wave sound the same value was demonstrated, it is also possible to set a gain for every component wave sound.

5] In the above embodiment, the first caution driving state is determined and a warning is given when the vehicle exceeds the determination region C. However, the determination of the first caution driving state may be omitted. In this case, by setting the accelerator opening A6 of the turning half-order component map so as to correspond to the determination region C, it is possible to alert the driver through the change of the sound effect.

6) In addition, those skilled in the art can implement the present invention in various forms added with various modifications without departing from the spirit of the present invention, and the present invention includes such modifications. is there.

V Vehicle 1 Sound effect generator 3 Rotational speed sensor 4 Accelerator opening sensor 11 Storage unit 12 Traveling state determination unit 13 Gain setting unit

Claims (1)

Engine speed detecting means, accelerator opening detecting means, gain setting means for setting gains of a plurality of integer components of engine speed based on the accelerator opening detected by the accelerator opening detecting means, and the gain In the vehicle sound effect generating device for generating sound effects based on the gain set by the setting means and the vibration sound database of the plurality of integer components,
A turning state determining means for determining a turning state of the vehicle;
When the vehicle is in a turning state, a gain of a low-order component among the plurality of integer order components is set to be larger than a gain of the low-order component in a state other than the turning state,
When the vehicle is turning and the accelerator opening is small, the gain increase rate of the low order component of the plurality of integer order components is set larger than the gain increase rate of the middle and high order components,
When the vehicle is in a turning state and the accelerator opening is large, a gain increase rate of a low order component among the plurality of integer order components is set to be smaller than a gain increase rate of a medium high order component. Vehicle sound effect generator.