JP2007031875A - Direction information communicator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a direction information communicator which can give located sound images and mechanical irritations to a helmet wearer, thereby making the wearer to clearly know a direction to be recognized. <P>SOLUTION: This direction information communicator is applied to a motorcycle BY, and comprises driver head phones 11 mounted on a helmet 10, vibrators 13, an alarm 22, a mounted unit 30, and the like. Alarm sound images based on sound signals are located on the basis of the sound signals generated from the alarm and their accompanied information (for example, the information of an obstacle-approaching direction), and at least one of vibrators 13 in the direction of the sound image-located position is vibrated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention provides a direction information notification device that gives information about a direction to an information acquirer wearing a helmet, for example, a direction of an object to be alarmed, a road to be advanced in a route guidance, or a direction in which an object exists. About.

Conventionally, a motorcycle driver's helmet is equipped with left and right speakers, and the headphone transfer function is used to localize the alarm sound so that the alarm sound can be heard from the direction of the object to be alarmed. A two-wheeled vehicle alarm device is known (for example, see Patent Document 1). According to this device, the driver can recognize the direction of an object or the like to which attention should be directed by sound.
JP 2000-355820 A

  However, in addition to the driver's consciousness focusing on driving, there are cases where noise such as wind noise is loud, so even if a sudden warning sound is localized, it is based only on that sound. In some cases, the direction of the warning sound (localization position) cannot be recognized. Such a problem is not limited to a driver's helmet such as a motorcycle, but attempts to recognize the direction of the sound based on "localized sound" generated from left and right speakers provided inside the helmet. It is a problem that generally exists in the device.

  The present invention has been made to solve the above problems, and one of its purposes is to recognize the wearer of the helmet by applying mechanical stimuli other than sound to the wearer of the helmet. An object of the present invention is to provide a direction information notification device that can make a user want to perceive a direction desired to be clear.

The direction information notifying device according to the present invention that achieves such an object,
Speakers provided on the left and right sides of the helmet, and sound image localization means for locating the sound image of the sound generated from the speakers to a predetermined sound image localization position based on predetermined information, to the helmet wearer by localization of the sound image A direction information notification device that provides information on at least a direction,
A plurality of stimulus applying means disposed at a plurality of locations of the helmet and each applying a local mechanical stimulus to the helmet wearer's head in response to an external signal;
Drive means for applying the external signal to at least one of the stimulus applying means disposed at a position corresponding to the predetermined sound image localization position;
It is an apparatus provided with.

  According to this, at least one of the stimulus applying means arranged at a position corresponding to the localization position of the sound image generated from the speaker of the helmet applies a local mechanical stimulus to the head of the helmet wearer. Therefore, the consciousness of the helmet wearer can be directed to the localized sound image not only by sound but also by mechanical stimulation.

  In this case, the plurality of stimulus applying means may be arranged such that the front side of the helmet has a shorter distance between two adjacent stimulus applying means than the rear side of the helmet. Is preferred.

  In general, the head-related transfer function for the front sound source is more complex than the head-related transfer function for the rear sound source. For this reason, it is not easy for the helmet wearer who is a listener (listener) to localize the sound source located in the front with high accuracy. Therefore, as in the above configuration, the “distance between two stimulating means adjacent to each other” on the front side of the helmet is the “distance between two stimulating means adjacent to each other” on the rear side of the helmet. By providing the stimulus applying means so as to be shorter than that, it is possible to give the helmet wearer high-density stimulus in the front direction in the forward direction that is difficult to accurately perceive only by sound. It can be perceived with high accuracy by means. As a result, even when the same number of stimulus applying means is used, the direction to be transmitted to the helmet wearer can be recognized with higher accuracy.

  Further, it is preferable that at least one of the plurality of stimulus applying means is disposed at a position corresponding to the median surface of the helmet wearer inside the helmet.

  In general, according to sound image localization using a head-related transfer function, it is more difficult to accurately localize a sound image in the median plane direction than to accurately locate a sound image in a horizontal plane direction. This is because the head-related transfer function in the median plane direction has a large difference (individual difference) between listeners, and the head-related transfer function in one median plane (front-rear) direction that suits various listeners is set (reproduced). Because it is difficult. Therefore, as in the above configuration, by arranging at least one of the stimulus imparting means at a position corresponding to the median plane of the helmet wearer, all directions including the median plane direction should be perceived by the helmet wearer. Can be recognized with high accuracy.

  Embodiments of a direction information notification device according to the present invention will be described below with reference to the drawings. In the present specification, claims and drawings, “sound source position (sound source virtual position)” means “sound image signal position (sound image position of sound source signal that is a signal for generating sound output from the sound source”. Virtual position) ”.

<First Embodiment>
(Device configuration)
As shown in FIG. 1, this direction information notification device is applied to a motorcycle BY, and a headphone 11 for a driver, a microphone 12 for a driver, all of which are attached to a full-face type driver's helmet 10, A plurality of vibrators 13 (13a to 13h) and a driver's helmet orientation detection geomagnetic sensor 14 are provided. The direction information notification device further includes a driver unit 15, a vehicle body direction detection geomagnetic sensor 21, an alarm device 22, and an in-vehicle unit 30.

  As shown in FIG. 1, FIG. 2 which is a perspective view of the helmet 10, and FIG. 3 which is a plan view of the helmet when the helmet 10 is viewed from above, the driver headphone 11 includes a left speaker 11L and a right speaker 11R. Yes. The left speaker 11L is disposed on the inner left side of the driver helmet 10 so as to be positioned near the left ear of the driver wearing the driver helmet 10. The right speaker 11 </ b> R is disposed on the right side inside the driver helmet 10 so as to be positioned in the vicinity of the right ear of the driver wearing the driver helmet 10.

  As shown in FIGS. 1 and 2, the driver microphone 12 is disposed at the lower front side inside the driver helmet 10 so as to be positioned near the mouth of the driver wearing the driver helmet 10. Has been.

  The plurality of vibrators 13 (13a to 13h in this example) are arranged at positions separated from each other along the circumferential direction of the head of the wearer of the helmet 10 as shown in FIGS. It is disposed and fixed at a position inside the facing helmet 10. Each of the plurality of vibrators 13 constitutes a stimulus applying means for applying a local mechanical stimulus to the head of the wearer of the helmet 10 in response to an external signal. For convenience, the vibrators 13a to 13h are also referred to as first to eighth vibrators in order.

  If it demonstrates in detail with reference to FIG. 3, the vibrator 13a is arrange | positioned in the front upper part position of the helmet 10 on the median surface CP of the wearer of the helmet 10. FIG. The median plane CP is a plane that divides the head of the wearer of the helmet 10 into two substantially symmetrical parts on the left and right, and is a plane that extends in the front-rear direction of the head and the vertical direction of the head passing through the center in the left-right direction of the head It is.

Similarly, the vibrator 13b to the vibrator 13h are disposed and fixed at the positions indicated by the angles θ1 and θ2 in Table 1 above the inside of the helmet 10. As shown in FIG. 3, the angles θ1 and θ2 are respectively clockwise and counterclockwise from the front of the helmet 10 (front of the longitudinal axis of the driver's helmet 10) around the center P of the helmet 10. It represents the rotated angle. Accordingly, the vibrator 13e is disposed on the median plane CP of the helmet wearer and at the rear upper position of the helmet 10.

  The driver's helmet orientation detection geomagnetic sensor 14 is disposed on the inner side or the upper outer side of the driver's helmet 10. The driver's helmet orientation detection geomagnetic sensor 14 detects the direction of the driver's helmet 10 (the direction ahead of the longitudinal axis of the driver's helmet 10).

  The driver unit 15 houses an electric circuit that achieves a predetermined function. As shown in FIGS. 1 and 2, the driver unit 15 is connected to a driver headphone 11, a driver microphone 12, a plurality of vibrators 13, and a driver's helmet orientation detection geomagnetic sensor 14 by a cord. Yes.

  The driver unit 15 drives the driver headphones 11 to generate sound from the driver headphones 11, selects a predetermined vibrator 13 among the plurality of vibrators 13, and vibrates the selected vibrator 13. The signal (external signal) to be transmitted is transmitted to the selected vibrator 13. Further, the driver unit 15 inputs an audio signal from the driver microphone 12 and inputs the orientation of the driver helmet 10 detected by the driver helmet orientation detection geomagnetic sensor 14. . The driver unit 15 exchanges necessary information with the in-vehicle unit 30 by wireless communication.

  The vehicle body direction detection geomagnetic sensor 21 is fixed to the vehicle body of the motorcycle BY. The vehicle body orientation detection geomagnetic sensor 21 detects the longitudinal direction of the vehicle body (the forward direction of the longitudinal axis of the vehicle body).

  The obstacle and alarm sound detection device (hereinafter referred to as “alarm device”) 22 is a known device using a technique described in, for example, Japanese Patent Laid-Open No. 2000-355820, and is a motorcycle. It is fixed to the BY body. The alarm device 22 is connected to sensors (not shown), and detects a direction in which an obstacle approaches (that is, a direction with respect to a vehicle body approaching an obstacle to notify the driver) based on signals from these sensors. It is supposed to be.

  Further, the alarm device 22 is connected to a plurality of highly directional microphones (not shown) disposed on the left and right and front and rear sides of the vehicle body, and detects an alarm or the like emitted from the periphery of the vehicle body. The direction (that is, the direction with respect to the vehicle body in which the alarm etc. which should be notified to a driver | operator generate | occur | produced) is determined.

  When the alarm device 22 detects an approach of an obstacle, an alarm, or the like, the alarm device 22 outputs a signal representing a sound source signal and accompanying information. The sound source signal is a signal generated from a certain sound source, and is a signal for generating a sound (in this case, an alarm sound) by the sound source. The accompanying information is information regarding sound to be generated based on the sound source signal, and in this case, is information regarding the direction of the obstacle with respect to the vehicle body and the distance between the vehicle body and the obstacle.

  The in-vehicle unit 30 is fixed to the vehicle body of the motorcycle BY. The vehicle-mounted unit 30 is connected to the vehicle body direction detection geomagnetic sensor 21 and the alarm device 22 by a cord, and inputs signals generated by these. The in-vehicle unit 30 further exchanges necessary information with the passenger unit 43 through wireless communication.

  As shown in FIG. 4, the in-vehicle unit 30 includes a communication device 31, a sound source position determination device 32, a sound source localization device (sound image localization means) 33 and a vibration pattern determination device 34.

  The communication device 31 exchanges signals with the driver unit 15 by wireless communication.

  The sound source position determination device 32 is connected to the vehicle body direction detection geomagnetic sensor 21, the alarm device 22, the communication device 31, the sound source localization device 33, and the vibration pattern determination device 34. The sound source position determination device 32 receives a sound source signal output from the alarm device 22 and a signal representing accompanying information.

  The sound source position determination device 32 determines a virtual sound source position (a sound image position of the sound source, a virtual sound source position with respect to the sound source), which is a position to localize a sound image based on the received sound source signal, based on the received sound source signal and a signal representing accompanying information. The information representing the virtual sound source position (sound source position information) is output to the sound source localization device 33 and the vibration pattern determination device 34.

  The virtual sound source position is a sound source (a sound image based on a sound source signal from the sound source) that can be heard by the driver (the person wearing the helmet 10) as if it is present at the virtual sound source position. It is a virtual position of the sound source that can be made. Therefore, the alarm device 22, the wireless communication device for conversation (described later) 35 and other sound sources 23 constitute a sound source.

  Further, the sound source position determination device 32 determines the sound source position information according to the output signal of the vehicle body direction detection geomagnetic sensor 21 and the output signal of the helmet direction detection geomagnetic sensor 14 received via the communication device 31. (Correction).

  The sound source localization device 33 is also connected to the communication device 31. The sound source localization device 33 receives a signal output from the alarm device 22 (a signal representing a sound source signal and accompanying information), receives sound source position information from the sound source position determination device 32, and converts a sound image based on the sound source signal into sound source position information. A sound source localization signal (output signal) that is a signal for localization to a position corresponding to the position is generated.

  Further, the sound source localization device 33 is configured to transmit a sound source localization signal to the driver unit 15 via the communication device 31. The driver unit 15 amplifies the received sound source localization signal and outputs the amplified signal to the speakers 11R and 11L of the driver headphone 11. As a result, sounds corresponding to the localized sound source signals are generated from the speakers 11R and 11L.

  Here, the configuration of the sound source localization apparatus 33 will be described with reference to FIG. The sound source localization device 33 includes a tap position determination circuit 33a, a gain determination circuit 33b, an A / D converter (ADC) 33c, a delay line 33d, a bandpass filter 33e, a gain multiplier 33f, a gain multiplier 33g, an adder 33h, and an FIR. A filter 33i, an adder 33j, and a D / A converter (DAC) 33k are provided. Note that the sound source localization device 33 and the sound source localization method (sound image localization method in which the sound image of a sound is localized in three dimensions using headphones) are well known, for example, from Japanese Patent Application Laid-Open Nos. 2002-44796 and 10-23600. .

  The tap position determination circuit 33a is connected to the sound source position determination device 32 and the delay line 33d. Based on the sound source position information from the sound source position determining device 32, the tap position determining circuit 33a transmits a signal indicating the tap position of the delay line 33d (the tap position will be described later) to the delay line 33d. .

  The gain determination circuit 33b is connected to the sound source position determination device 32, the gain multiplier 33f, and the gain multiplier 33g. Based on the sound source position information from the sound source position determination device 32, the gain determination circuit 33b transmits a signal indicating gains described later of the gain multiplier 33f and the gain multiplier 33g to the gain multiplier 33f and the gain multiplier 33g. It is like that.

  The input end of the ADC 33 c is connected to the alarm device 22. The ADC 33c converts the sound source signal input from the alarm device 22 into a digital signal and outputs it from the output end. The output end of the ADC 33c is connected to the input ends of the gain multipliers 33f of the first channel Ch1 to the eighth channel Ch8, and is also connected to the input end of the delay line 33d. A signal directly input from the output end of the ADC 33c to the input end of the gain multiplier 33f of the first channel Ch1 to the eighth channel Ch8 is referred to as “preceding sound”.

  The delay line 33d is composed of a plurality of shift registers. The plurality of shift registers are connected in series to form a multistage shift register. The delay line 33d is provided with a tap between a predetermined register of the multistage register and a register subsequent to the predetermined register.

  A signal that is input from the output end of the ADC 33c to the delay line 33d and delayed from the tap by a predetermined time and is extracted from the tap is referred to as “following sound”. The delay line 33d changes the tap position based on a signal transmitted from the tap position determination circuit 33a.

  The tap of the delay line 33d is connected to the input end of the bandpass filter 33e. The output end of the band pass filter 33e is connected to the input ends of the gain multipliers 33g of the first channel Ch1 to the eighth channel Ch8. As a result, the succeeding sound is input to the input terminals of the gain multipliers 33g of the first channel Ch1 to the eighth channel Ch8 after passing through the band pass filter 33e.

  Both the gain multiplier 33f and the gain multiplier 33g of each channel are connected to the gain determination circuit 33b. Thus, each gain multiplier 33f changes its own gain based on the signal output from the gain determination circuit 33b. Similarly, each gain multiplier 33g changes its own gain based on the signal output from the gain determination circuit 33b.

  By the way, in general, when a listener listens to two sounds that are the same as each other, such as a preceding sound and a following sound, with a time difference, the listener can hear the sound that has reached earlier and / or the sound with the higher level. Perceive that sound source of the sound exists in the direction. This effect is a well-known effect called a precedence sound effect (Haas effect). Accordingly, the gain of the gain multiplier 33g is appropriately changed so that the subsequent sound is positioned on the opposite side of the preceding sound with respect to the listening position, and the position of the tap on the delay line 33d is changed to change the preceding sound. Adjust the time difference (delay time) between the sound and the following sound. Thereby, it is possible to further emphasize the sense of direction of the preceding sound to be localized.

  However, if the time difference and level difference between the preceding sound and the following sound are extremely small, the sound image is localized in the head and the sense of direction is lost. Conversely, if the time difference is excessive, the listener perceives the received sound as two separate sounds. Further, if the level difference is excessive, the effect of the following sound (an effect of enhancing the direction feeling of the preceding sound) is lost.

  Based on such a viewpoint, the tap position determination circuit 33a and the gain determination circuit 33b are configured to set the time difference (tap position) and the level difference (gain for the following sound) to appropriate values.

  The output terminal of the gain multiplier 33f for each channel and the output terminal of the gain multiplier 33g are connected to the input terminal of the adder 33h for each channel. The output terminal of the adder 33h for each channel is connected to the input terminal of the FIR filter 33i (actually, the left ear FIR filter 33iL and the right ear FIR filter 33iR) for each channel. As a result, the preceding sound signal and the following sound signal are amplified by the gain multiplier 33f and the gain multiplier 33g, added by the adder 33h, and then input to the FIR filter 33i.

  The FIR filter 33iL of the first channel Ch1 simulates the frequency characteristics when sound is heard from the direction of # 1 in FIG. 6 to the listener's left ear using a head related transfer function (HRTF). It is like that. That is, the FIR filter 33iL of the first channel Ch1 uses the head-related transfer function that is the sound transfer characteristic when the sound is heard from the direction of # 1 in FIG. This is a filter that performs a convolution operation on the signal output from the adder 33h.

  In FIG. 6, the head of the listener (driver) exists in the center of the cube defined by the positions of # 1 to # 8, and the listener is # 1, # 2, # 6 and # 5. It faces the surface formed by the position of (that faces in the vertical direction of this surface). The surface formed by the positions # 1 to # 4 is the lower surface of the listener, and the surface formed by the positions # 5 to # 8 is the upper surface of the listener. The direction of the cube changes with a change in the direction of the listener's head (the direction in front of the front-rear axis of the driver's helmet 10).

  Similarly, the FIR filter 33iL and the FIR filter 33iR of the second channel Ch2 to the eighth channel Ch8 respectively transmit the sound from the directions # 2 to # 8 in FIG. 6 to the left and right ears of the listener. To simulate.

  Here, a case where the virtual sound source position is the direction between the basic directions # 1 to # 8 described above will be described. Now, it is assumed that the virtual sound source position should be set to an arbitrary point Ptgt on the space shown in (A) to (C) of FIG. In this case, the virtual sound source Ptgt is in a square formed by # 1, # 2, # 5, and # 6 when viewed from the central point D of the listener's left and right ears. 7B and 7C are a top view and a side view of the cube of FIG. 7A, respectively.

  Here, the intersection of the straight line L passing through the point D and the point Ptgt and the surface formed by the positions of # 1, # 2, # 5 and # 6 is referred to as an intersection point Cr. In this case, the intersection Cr is the length of the side # 1- # 2 (A in FIGS. 6 and 7) in the horizontal direction (the horizontal direction, that is, the direction along # 1- # 2 or # 5- # 6). ) Is present at a position P1 obtained by dividing the length of one side of the cube shown in FIG. Furthermore, the intersection point Cr is the length of the side # 1- # 5 ((A in FIGS. 6 and 7) in the vertical direction (vertical vertical direction, that is, the direction along # 1- # 5 or # 2- # 6). ) Is present at a position P2 that is internally divided by c: d. The distance L1 from the point D to the virtual sound source Ptgt is assumed to be x times the distance L2 from the point D to the intersection Cr (sound source distance ratio x = L1 / L2).

At this time, the gain determination circuit 33b sets the gain of the gain multiplier 33f for each preceding sound of the first channel Ch1, the second channel Ch2, the fifth channel Ch5, and the sixth channel Ch6 to the inter-channel distance ratios a: b, c. : Set to gain obtained from d and sound source distance ratio x. Specifically, the gain of each channel may be determined so as to be inversely proportional to the interchannel distance ratio and inversely proportional to the square of the sound source distance ratio x. That is, the gain kChn (n is 1, 2, 5, 6) for the preceding sound of the nth channel is determined by the following equations (1) to (4). Further, the gain of the remaining channel of the gain multiplier 33f is set to “0”.

The virtual sound source Ptgt ′ of the following sound is localized at a point-symmetrical position with respect to the point D of the virtual sound source Ptgt localized by the preceding sound in order to bring about the effect of the following sound. The following sound is pronounced so as to have a certain amount of attenuation (gain) and delay amount (time difference) with respect to the preceding sound. These amounts (attenuation amount and delay amount) do not depend on the sound source position, and are set based on the listener's listening characteristics and preferences. Now, assuming that the amount of attenuation with respect to the preceding sound is p, the gain determining circuit 33b sets the gain of the gain multiplier 33g for each succeeding sound of the third channel Ch3, the fourth channel Ch4, the seventh channel Ch7 and the eighth channel Ch8. In accordance with the gain for the preceding sound, it is determined based on the following formulas (5) to (8). Further, the gain for the subsequent sound of the remaining channel of the gain multiplier 33g is set to “0”.

  When the direction of the driver's helmet 10 (direction of the driver's headphones 11) and / or the point Ptgt which is the virtual sound source position changes, the angle formed by the point Ptgt and the driver's headphones 11 also changes. Also in this case, the straight line L passing through the point D and the point Ptgt intersects with any surface of the cube formed by the positions # 1 to # 8, and the intersection point Cr is obtained on the surface. Therefore, the gain determining circuit 33b determines the distance ratio (inter-speaker distance ratio) a: b, c: d, and the above-described distance ratios from four positions among the positions # 1 to # 8 that define the intersection Cr and its surface. The sound source distance ratio x is obtained, and the gain of the preceding sound gain multiplier 33f and the gain of the succeeding sound gain multiplier 33g of each channel are set to gains determined by these ratios and the above (1) to (8). As a result, the virtual sound source position can always be localized at the point Ptgt regardless of the direction of the driver headphones 11.

  Referring to FIG. 5 again, the FIR filters 33iL and 33iR of each channel are connected to the input terminals of the adder 33j (actually, the left ear adder 33jL and the right ear adder 33jR). Thereby, the signals output from the FIR filters 33iL and 33iR of each channel are added and synthesized by the adder 33j.

  The output terminals of the adder 33j (the left ear adder 33jL and the right ear adder 33jR) are independently connected to the input terminal of the DAC 33k. Thereby, the signal output from each adder 33j is converted into an analog signal. The output end of the DAC 33k is connected to the communication device 31. Thereby, the signals for the left ear and the right ear (sound source localization signals) converted into analog signals are transmitted to the driver unit 15 via the communication device 31.

  Referring to FIG. 4 again, the vibration pattern determination device 34 is also connected to the communication device 31. The vibration pattern determination device 34 receives sound source position information from the sound source position determination device 32, determines (one or more) vibrators to be vibrated from among the plurality of vibrators 13a to 13h based on the sound source position information, A signal (vibrator selection signal) representing the determined vibrator is generated. The vibration pattern determination device 34 may be configured to acquire a sound source localization signal from the sound source localization device 33 and determine a vibrator to be vibrated based on the sound source localization signal.

  The above-described “vibrator to be vibrated” is a vibrator disposed at a position corresponding to the sound image localization position (virtual sound source position). For example, as shown in FIG. 3, when the position when the sound image localization position is projected onto the surface on which the plurality of vibrators 13 are disposed is a position Ptgt1 indicated by a triangular plot, the vibration pattern determination device 34 The vibrator to be vibrated is determined to be the second vibrator 13b. When the sound image localization position is a position Ptgt2 indicated by a square plot when the sound image localization position is projected on the surface on which the plurality of vibrators 13 are disposed, the vibration pattern determination device 34 determines that the vibrator to be vibrated is the fourth. It is determined to be the vibrator 13d.

  Thus, the vibration pattern determination device 34 determines the position where the sound image localization position is projected on the surface where the plurality of vibrators 13 are disposed, and a line segment connecting the position and the center P of the helmet (hereinafter, referred to as “the helmet pattern P”). The vibrator closest to the “localization direction line segment”) is determined as “vibrator disposed at a position corresponding to the sound image localization position”, that is, “vibrator to be vibrated”. In other words, the vibrator in the direction closest to the direction of the sound image localization position is selected as the “vibrator to be vibrated”.

  Furthermore, the vibration pattern determination device 34 is configured to transmit a vibrator selection signal to the driver unit 15 via the communication device 31. The driver unit 15 outputs a drive signal that vibrates the vibrator indicated by the received vibrator selection signal to the corresponding vibrator. As a result, the vibrator disposed at the position corresponding to the sound image localization position (virtual sound source position) is vibrated.

(Actual operation)
Next, the operation of the direction information notification apparatus configured as described above will be described. The functions of the sound source position determining device 32 and the vibration pattern determining device 34 described above are actually achieved by the CPU of the microcomputer performing the processing shown by the flowcharts in FIGS. 8 and 11 at regular intervals. The function of the sound source localization device 33 is achieved by a DSP (digital signal processor) performing the processing shown by the flowchart in FIG. Now, it is assumed that the alarm device 22 has not detected an approach of an obstacle to be notified to the driver, an alarm to be notified to the driver, or the like, and therefore has not generated a sound source signal.

  When the CPU of the sound source position determination device 32 starts the processing from step 100 shown in FIG. 8, the CPU proceeds to step 110 and moves the angle of the driver helmet 10 relative to the front of the longitudinal axis of the motorcycle BY (the driver helmet 10 Is determined based on the vehicle body direction detected by the vehicle body direction detection geomagnetic sensor 21 and the direction of the driver helmet 10 detected by the driver helmet direction detection geomagnetic sensor 14.

  Next, the CPU proceeds to step 120 to determine whether or not a sound source signal from the alarm device 22 is generated. According to the above assumption, no sound source signal is generated at the present time. Therefore, the CPU makes a “No” determination at step 120 to directly proceed to step 195 to end the present routine tentatively. The above steps are repeated until a sound source signal is generated from the alarm device 22. Step 120 is a step for detecting the generation of a sound source signal.

  In this state, it is assumed that the alarm device 22 detects an approach of an obstacle to be notified to the driver or an alarm to be notified to the driver. In this case, the alarm device 22 outputs a sound source signal and accompanying information. Therefore, the CPU makes a “Yes” determination at step 120 following step 110 shown in FIG. 8, and proceeds to step 130 to determine the virtual sound source position, that is, the position where the alarm sound should be localized, with the accompanying information of the sound source signal. And it determines based on direction (angle) of the helmet 10 for drivers determined in step 110. FIG.

  By the way, as shown in FIG. 9A, the alarm device 22 detects that an obstacle is approaching from the right front of the body of the motorcycle BY, and warns that by an alarm sound. It is assumed that a sound source signal is generated. At this time, it is assumed that the driver (driver's helmet 10) is facing the front of the longitudinal axis of the body of the motorcycle BY. In this case, the sound image of the alarm sound based on the sound source signal from the alarm device 22 may be localized at the front right of the helmet 10 (headphone 11).

  However, as shown in FIG. 9 (B), the driver turned to the direction rotated in the clockwise direction by 90 degrees in the plan view with respect to the front of the front-rear axis of the motorcycle (that is, right). Then, the sound image of the alarm sound based on the sound source signal from the alarm device 22 should be localized to the left front of the helmet 10 (headphone 11).

  Therefore, the CPU of the sound source position determination device 32 determines the virtual sound source position of the sound source signal in accordance with the direction of the driver's helmet 10 in step 130 described above. Accordingly, in the example shown in FIG. 9B, the sound image of the alarm sound is localized in the left front of the helmet 10 (headphone 11), so that the driver can erroneously recognize the approaching direction of the obstacle. Can be reduced.

  Next, the CPU of the sound source position determining device 32 proceeds to step 140, outputs the sound source position information determined in step 130, proceeds to step 195, and once ends this routine.

  On the other hand, the sound source localization device 33 (DSP) starts the processing of the routine shown in FIG. 10 from step 200 every elapse of a predetermined time, proceeds to step 210, and is based on “sound source position information output by the CPU”. Then, the coefficients of the FIR filters 33iL and 33iR with respect to the virtual sound source position of the sound source signal are determined. Next, the DSP proceeds to step 220 and determines the gain of the gain multiplier 33f and the gain of the gain multiplier 33g. The gain of the gain multiplier 33f and the gain of the gain multiplier 33g are determined for each of the first channel Ch1 to the eighth channel Ch8 based on the above-described equations (1) to (8).

  Next, the DSP proceeds to step 230 and causes the ADC 33c to perform AD conversion of the sound source signal. Thereby, the DSP acquires the sound source signal after AD conversion. If the sound source signal output from the alarm device 22 is a digital signal, step 230 and the ADC 33c are omitted. Next, the DSP proceeds to step 240 and uses the coefficients of the FIR filters 33iL and 33iR determined in step 210 and the gain of the gain multiplier 33f and the gain of the gain multiplier 33g determined in step 220. Then, a signal (sound source localization signal) for localizing a sound image (alarm sound) based on the sound source signal to a position corresponding to the sound source position information is generated.

  Thereafter, the DSP proceeds to step 250 where the sound source localization signal generated in step 240 is converted into an analog signal by the DAC 33k, and the sound source localization signal converted into the analog signal is output to the driver unit 15 via the communication device 31. To do. Then, the DSP once ends this routine at step 295. Thus, the alarm sound is localized at the virtual sound source position.

  On the other hand, the CPU starts the processing of the routine shown in FIG. 11 from step 300 every elapse of a predetermined time, and proceeds to step 310 to determine the vibrator to be vibrated based on the sound source position information based on the method described above. . That is, the CPU generates a vibrator selection signal. In this case, the CPU includes a vibrator vibration pattern database similar to the sound source position pattern database, and determines a vibrator to be vibrated from at least one of the type of the sound source signal and the type of the sound source signal and the vibrator vibration pattern database. May be. Next, the CPU proceeds to step 320, outputs a vibrator selection signal to the driver unit 15 via the communication device 31, and once ends the routine at step 395. As a result, at least one of the vibrators 13 that substantially matches the direction in which the alarm sound is heard vibrates.

  As described above, the direction information notification device according to the first embodiment of the present invention uses sound information of sounds (alarm sounds) generated from the speakers 11R and 11L provided on the left and right in the helmet 10 as predetermined information. Sound image localization means (sound source position determination device 32, sound source localization device 33 and driver unit 15) for localization to a predetermined sound image localization position (a position where an alarm sound should be generated) based on (accompanying information) is provided. Therefore, information regarding at least the direction (the direction to which attention should be paid) is given to the helmet wearer by the localization of the sound image. Furthermore, since the sound image of the sound source signal is localized, the helmet wearer can be made to recognize the specific sound direction and sense of distance.

  In addition, the direction information notification device includes a plurality of stimulation applying means (vibrators 13a to 13h) that apply local mechanical stimulation to the head of the helmet wearer according to an external signal (vibrator selection signal), Drive means (vibration pattern determination device 34 and driver unit 15) for applying the external signal to at least one of the stimulus applying means disposed at a position corresponding to a predetermined sound image localization position. Therefore, since a mechanical stimulus is generated in a local portion of the helmet wearer's head in a direction substantially equal to the direction of the predetermined sound image localization position, the helmet wearer can only listen to sound (sound image localization). Without any mechanical stimulation, it is possible to easily direct self-consciousness in the direction of the localized sound image.

  Furthermore, in the said direction information alerting | reporting apparatus, the distance between the two vibrators which the front side of the said helmet 10 adjoins mutually rather than the back side of the said helmet is set. Therefore, the helmet wearer can accurately recognize the direction of the sound from the front (the sound image localized in the front direction) from which it is difficult to obtain the localization feeling by the sound image localization by the vibration of the vibrator 13 arranged with high density.

  In addition, the vibrator 13a and the vibrator 13e are disposed at an inner position of the helmet 10 corresponding to the median surface of the helmet wearer. Therefore, the direction to be transmitted to the helmet wearer can be recognized with higher accuracy.

  In the above embodiment, the alarm sound is localized and at least one of the vibrators 13 is vibrated accordingly. However, the sound to be localized is “a sound related to information that the helmet wearer wants to recognize about the direction”. If it is, it is not restricted to a warning sound.

Second Embodiment
As shown by broken lines in FIGS. 1 and 4, the direction information notification device according to the second embodiment includes other sound sources 23 such as a music player and a voice navigator device in addition to the alarm device 22. By generating sound based on sound source signals from other than the vehicle and communicating with the passenger unit 43, the helmet wearer who is the driver of the motorcycle BY can communicate with the passenger wirelessly. This is different from the direction information notification device of the first embodiment. Accordingly, the following description will focus on such differences.

  The other sound source 23 may be any of a mobile phone, a music player, a navigation device, a vehicle / running state detection device, and the like, and may be a device having an integrated function.

  The mobile phone is a mobile phone that is generally used, and outputs at least a signal that represents a ring tone and a signal that represents a call voice. The music player is, for example, an MP3 player or the like, and stores music data therein or acquires it by communication from the outside, and outputs a signal for playing music based on the music data. . The navigation device incorporates a GPS device. The GPS device is adapted to receive a navigation radio wave for detecting the position of the own vehicle radiated from a GPS (Global Positioning System) satellite and acquire the current position of the motorcycle BY. The navigation apparatus obtains a route from a current position to a destination set by a predetermined operation by calculation, and outputs a signal for performing route guidance by voice.

  The vehicle / running state detection device is connected to various sensors, switches, and the like (not shown) that detect the state of the motorcycle BY. The vehicle / running state detection device detects a vehicle state including an abnormal state of each part of the motorcycle BY and a running state of the motorcycle BY based on a signal from the connected sensor, and detects the detected vehicle / running state. A signal for informing the driver by voice or warning sound is output as necessary. The vehicle state includes, for example, a blinking state of the direction indicator (including which of the left and right direction indicators is blinking), an abnormality in the brake system, and a low amount of fuel. The traveling state includes, for example, a state such as an engine rotation speed, a vehicle speed, a road surface state obtained by wireless communication from a device external to the vehicle disposed on the road surface, a roadside belt, or the like.

  In addition, when a passenger gets on the motorcycle BY, the direction information notification device includes the passenger headphone 41 and the passenger microphone 42 mounted on the passenger helmet 40, and the passenger unit 43. Become.

  The in-vehicle unit 30 is connected to the other sound source 23 and receives a signal from the other sound source 23 (a signal representing a sound source signal and accompanying information). Further, the in-vehicle unit 30 includes a conversation wireless communication device 35. The conversation wireless communication device 35 exchanges signals with the passenger unit 43 by wireless communication.

  The conversation wireless communication device 35 is connected to the communication device 31, and the passenger unit 43 receives the “voice signal based on the voice generated by the driver (the person wearing the helmet 10)” received from the driver unit 15 by the communication device 31. To be sent to. The conversation wireless communication device 35 is connected to the sound source position determination device 32 and the sound source localization device 33, and is sent from the passenger unit 43 to the voice generated by the passenger (the person wearing the helmet 40). The "sound signal based on" is transmitted to the sound source position determination device 32 and the sound source localization device 33.

  The passenger unit 43 is connected to the passenger headphones 41 and the passenger microphone 42 by a cord. The passenger unit 43 drives the passenger headphones 41 in response to the “voice signal based on the voice generated by the driver (the person wearing the helmet 10)” obtained by communication with the conversation wireless communication device 35. Sound is generated from the passenger headphones 41. The passenger unit 43 receives a voice signal from the passenger microphone 42 and transmits the voice signal to the conversation wireless communication device 35.

  With the above configuration, the sound source position determination device 32 according to the second embodiment receives not only the alarm device 22 but also a sound source signal output from the other sound source 23 and the conversation wireless communication device 35 and a signal representing accompanying information. It is like that.

  Furthermore, the sound source position determination device 32 according to the second embodiment includes a sound source position pattern database 32a. In the sound source position pattern database 32a, a virtual sound source position pattern corresponding to at least one of the type of the sound source signal and the change in the type of the sound source signal is stored in advance. The sound source position determination device 32 is a virtual to be realized based on the type of the sound source signal from each sound source actually input, the change in the type of the sound source signal, and the relationship stored in the sound source position pattern database 32a. A sound source position pattern is determined, and information representing the pattern is output as the sound source position information described above.

  In addition, the sound source localization apparatus 33 according to the second embodiment is configured to localize the sound source for each sound source signal based on the sound source position information. Further, the vibration pattern determination device 34 according to the second embodiment selects at least one of the vibrators 13 only when there is a change in the type of the sound source (addition of a new sound source signal), and the type of the sound source signal is selected. The selected vibrator is vibrated for a predetermined time from the time of the change.

  Next, the operation of the direction information notification device according to the second embodiment configured as described above will be described using an example.

  For example, as shown in FIG. 12A, it is assumed that the driver plays music based on only the sound source signal generated by the music player included in the other sound source 23 and listens to the music. In this case, the sound source position determination device 32 is a music player so that the music to be reproduced spreads over the entire driver's head (driver's helmet 10) and the music can be heard with a natural feeling as when listening to normal music. The virtual sound source position for the sound image of the sound source signal from is determined. Then, the sound source localization device 33 localizes the sound image based on the sound source signal from the music player at the virtual sound source position. As a result, as if the driver enjoys music at an appropriate position within the range surrounded by four speakers (front left speaker, front right speaker, rear left speaker and rear right speaker). Can be heard.

  In this state, it is assumed that the passenger starts a conversation (speaks) using the passenger microphone 42 and the passenger unit 43. That is, it is assumed that the tandem conversation is started by the passenger's speech. In general, when a driver listens to music, attention is concentrated on the music, so there is a high possibility that the driver will miss an unexpected remark from the passenger.

  Therefore, as shown in FIG. 12B, the sound source position determination device 32 refers to the sound source position pattern database 32a and is a sound source as if the passenger's voice was emitted in the immediate vicinity of the driver. The position of the sound image (virtual sound source position) based on the sound source signal from the conversation wireless communication device 35 (passenger as a sound source) is determined.

  At the same time, the sound source position determination device 32 determines the position (virtual sound source position) of the sound image based on the sound source signal from the music player so that the music based on the sound source signal from the music player can be heard from below the driver's helmet 10. As a result, the driver suddenly hears music from below and hears the passenger's remarks in his / her ear, so the possibility that the driver misses the passenger's first conversation is reduced.

  Furthermore, when the new sound source signal (in this case, the passenger's voice signal from the conversation wireless communication device 35) is added, the vibration pattern determination device 34 is newly added based on the sound source position information. At least one of the vibrators 13 corresponding to the direction of the virtual sound source position (localization position) of the sound source signal is selected. In this case, the localization position of the passenger's voice signal which is a newly added sound source signal is in the left and right directions. Therefore, the vibration pattern determination device 34 selects the vibrators 13c and 13g and vibrates them for a predetermined time.

  Thereafter, when the conversation with the passenger continues, the sound source signals from the music player and the wireless communication device for conversation 35 (passenger) continue. That is, the type of sound source does not change. However, in this case, the type of sound source signal (combination of the types of sound source signals) is different from the case where only the music shown in FIG.

  Therefore, the sound source position determination device 32 is based on the sound source signal from the music player so that the music based on the sound source signal from the music player can be heard from below the helmet 10 for the driver, as shown in FIG. While determining the position of the sound image (virtual sound source position), the sound image based on the sound source signal from the conversation wireless communication device 35 so that the passenger's voice can be heard not over the driver but in the entire upper part of the driver's helmet 10 Is determined (virtual sound source position).

  When such a state continues, it is assumed that the navigation device of the other sound source 23 has generated a sound source signal for notifying by voice that the road on which the driver should travel is right front. In this case, the sound source position determining device 32 refers to the sound source position pattern database 32a so as not to hear music based on the sound source signal from the music player, and the passenger based on the sound source signal from the conversation wireless communication device 35 is used. Of the sound image based on each sound source signal so that the route guidance sound based on the sound source signal from the other sound source 23 can be heard from the right front of the driver helmet 10. Determine the virtual sound source position. Accordingly, the driver can surely know that the direction to travel is the right front direction and can continue the conversation with the passenger.

  At the same time, when a new sound source signal (in this case, a route guidance voice signal from another sound source 23) is added, the vibration pattern determination device 34 adds a virtual sound source of the newly added sound source signal based on the sound source position information. At least one of the vibrators 13 corresponding to the direction of the position is selected. In this case, the virtual sound source position (localization position) of the route guidance voice signal which is a newly added sound source signal is the front right direction. Therefore, the vibration pattern determination device 34 selects the vibrator 13b and vibrates the vibrator 13b for a predetermined time. The above is the outline | summary of an action | operation of the direction information alerting | reporting apparatus which concerns on 2nd Embodiment demonstrated using the example.

  Next, an actual operation of the direction information notification device according to the second embodiment will be briefly described. The functions of the sound source position determining device 32 and the vibration pattern determining device 34 described above are actually achieved by the CPU of the microcomputer performing the processing shown by the flowcharts in FIGS. 13 and 14 at regular intervals. The function of the sound source localization device 33 is achieved by the DSP performing the same process as in FIG.

  When the process of FIG. 13 is started from step 400, the CPU determines the orientation of the driver's helmet 10 at step 405 as in step 110 of FIG. Next, the CPU determines in step 410 whether or not the state of the sound source has changed, that is, whether or not a sound source signal from another sound source has been newly generated in addition to the sound source signal from the sound source up to that point. To do.

  At this time, if a sound source signal from another sound source is newly generated, the CPU proceeds to step 415 to read a sound source position pattern corresponding to the current situation from the sound source position pattern database 32a. Thereafter, the CPU proceeds to step 420 to correct the virtual sound source position of each sound source signal based on the sound source position pattern read in step 415 and the direction of the driver's helmet 10 determined in step 405. The virtual sound source position of each sound source is determined. Next, the CPU proceeds to step 425, outputs the virtual sound source position of each sound source signal determined in step 420 to the sound source localization device (DSP) 33 as sound source position information, proceeds to step 495, and once ends this routine.

  On the other hand, if the state of the sound source has not changed, the CPU makes a “No” determination at step 410 to proceed to step 430, where “whether or not a predetermined time has passed since the sound source state last changed”. Determine. If the predetermined time has not elapsed since the last change of the sound source status, the CPU proceeds directly to step 420 and thereafter. If a predetermined time has elapsed since the sound source status last changed, the CPU makes a “Yes” determination at step 430 to proceed to step 435, where the current status (a specific type of sound source signal is detected). The sound source position pattern corresponding to the situation that has continued for a predetermined time or more) is read from the sound source position pattern database 32a, and then the process proceeds directly to step 420 and thereafter. As described above, the CPU determines sound source position information.

  Further, the CPU repeatedly outputs the vibrator selection signal by repeatedly performing the process shown in FIG. 14 every elapse of a predetermined time. That is, the CPU determines whether or not it is immediately after a new sound source signal is generated in step 510 following step 500 based on the sound source position information. Then, if a new sound source signal is generated, the CPU proceeds to step 520, where the vibrator corresponding to the virtual sound source position (localization position) of the new sound source signal is vibrated based on the sound source position information. decide. That is, the CPU generates a vibrator selection signal. Then, the CPU proceeds to step 530, outputs the vibrator selection signal for a predetermined time, proceeds to step 595, and once ends this routine.

  On the other hand, if not immediately after the generation of a new sound source signal, the CPU makes a “No” determination at step 510 to directly proceed to step 595 to end the present routine tentatively.

  As described above, the sound source position determination device 32 according to the second embodiment determines each virtual sound source position according to at least one of the type of the sound source signal and the change of the type of the sound source signal. The sound source position determination device 32 actually stores in advance a virtual sound source position pattern corresponding to at least one of the type of the sound source signal and the type of the sound source signal in the sound source position pattern database 32a. The sound source position determination device 32 is realized based on the type of the sound source signal from each sound source actually input and the change in the type of the sound source signal and the relationship stored in the sound source position pattern database 32a. The pattern of the virtual sound source position to be determined is determined.

  A sound image based on a sound source signal corresponding to each virtual sound source position is localized at each determined virtual sound source position. Accordingly, the helmet wearer who is a listener can easily recognize which sound source is generating sound at the present time, which sound is important at the present time, and the like. Moreover, the helmet wearer can intuitively select and listen to a sound necessary at the present time from sounds based on a plurality of sound source signals generated from a plurality of sound sources.

  Further, the vibration pattern determination device 34 of the direction information notification device according to the second embodiment corresponds to the direction of the localized sound image of the sound source signal newly added from the plurality of vibrators 13 when a new sound source signal is added. The vibrator to be selected is selected, and the vibrator is vibrated for a predetermined time. Therefore, even when there are a plurality of sound sources, the information on the direction is reported not only by the localized sound image but also by mechanical vibration, so that the helmet wearer (driver) has information on the direction of important sound source signals. Can be surely acquired.

  In addition, this invention is not limited to said each embodiment, A various modification can be employ | adopted within the scope of the present invention. For example, the vibration pattern determination device 34 obtains a position where a sound image localization position is projected on a surface on which a plurality of vibrators 13 are disposed, and a vibrator closest to a line segment connecting the position and the center P of the helmet; The next closest vibrator may be determined as the “vibrator to be vibrated”.

  Further, when the two vibrators are determined as “vibrators to be vibrated” as described above, the vibration frequency and / or vibration amplitude of the vibrator closer to the localization direction line segment is set to be higher than that of the vibrator far from the localization direction line segment. You may enlarge it. Furthermore, the vibration frequency and / or vibration amplitude of the vibrator may be increased as the length of the localization direction line segment (virtual distance between the localized sound source and the helmet 10) is shorter.

  Further, in each of the above embodiments, the vibrator 13 is employed as the stimulus imparting means. For example, air injection is employed as the stimulus imparting means, whereby locally high pressure air is directed toward the head of the helmet wearer. May be injected.

  Further, in each of the above embodiments, the plurality of vibrators 13 are arranged on the substantially same plane inside the helmet 10, but may be arranged on two or more different planes, or predetermined each other. You may provide inside the helmet 10 so that the whole head may be covered, having a space | interval.

  In addition, the passenger's helmet 40 is also provided with a plurality of vibrators in the same manner as the driver's helmet 10, and by vibrating the vibrator in the same direction as the driver's helmet 10, the direction to be recognized is given to the passenger. You may make it alert | report.

It is a schematic block diagram of the direction information alerting | reporting apparatus which concerns on 1st and 2nd embodiment of this invention. It is a perspective view of the helmet for drivers | operators shown in FIG. It is a top view of the helmet for drivers | operators shown in FIG. It is a circuit block diagram of the direction information alerting | reporting apparatus shown in FIG. FIG. 3 is a circuit block diagram of the sound source localization apparatus shown in FIG. 2. It is a figure for demonstrating the sound image localization method by the direction information alerting | reporting apparatus shown in FIG. (A) thru | or (C) is a figure for demonstrating the sound image localization method by the direction information alerting | reporting apparatus shown in FIG. It is the flowchart which showed the process sequence which the sound source position determination apparatus shown in FIG. 2 performs. It is a figure for demonstrating the relationship between the direction of the helmet for drivers | operators, and the direction of a warning sound. It is the flowchart which showed the process sequence which the sound source localization apparatus shown in FIG. 2 performs. It is the flowchart which showed the process sequence which the vibration pattern determination apparatus shown in FIG. 2 performs. It is the figure which showed an example of the sound source localization pattern by the direction information alerting | reporting apparatus which concerns on 2nd Embodiment of this invention. It is the flowchart which showed the process sequence which the sound source position determination apparatus of the direction information alerting | reporting apparatus which concerns on 2nd Embodiment of this invention performs. It is the flowchart which showed the process sequence which the vibration pattern determination apparatus of the direction information alerting | reporting apparatus which concerns on 2nd Embodiment of this invention performs.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Driver's helmet, 11 ... Driver's headphone, 11R ... Right speaker, 11L ... Left speaker, 12 ... Driver's microphone, 13, 13a-13h ... Vibrator, 14 ... Geomagnetic sensor for driver's helmet direction detection DESCRIPTION OF SYMBOLS 15 ... Driver unit, 21 ... Detection geomagnetic sensor for vehicle body direction detection, 22 ... Alarm device, 23 ... Other sound source, 30 ... In-vehicle unit, 31 ... Communication device, 32 ... Sound source position determination device, 32a ... Sound source position Pattern database 33 ... Sound source localization device 33a ... Tap position determination circuit 33b ... Gain determination circuit 33c ... A / D converter 33d ... Delay line 33e ... Band pass filter 33f ... Gain multiplier 33g ... Gain multiplication 33h ... adder, 33i ... FIR filter, 33iL ... FIR filter for left ear, 3iR: FIR filter for right ear, 33j: Adder, 33jR: Adder for right ear, 33jL ... Adder for left ear, 33k ... D / A converter, 34 ... Vibration pattern determination device, 35 ... Wireless communication device for conversation , 40 ... Passenger helmet, 41 ... Passenger headphones, 42 ... Passenger microphone, 43 ... Passenger unit, CP ... Midline.

Claims (3)

Speakers provided on the left and right sides of the helmet, and sound image localization means for locating the sound image of the sound generated from the speakers to a predetermined sound image localization position based on predetermined information, to the helmet wearer by localization of the sound image A direction information notification device that provides information on at least a direction,
A plurality of stimulus applying means disposed at a plurality of locations of the helmet and each applying a local mechanical stimulus to the helmet wearer's head in response to an external signal;
Drive means for applying the external signal to at least one of the stimulus applying means disposed at a position corresponding to the predetermined sound image localization position;
A direction information notification device comprising: In the direction information notifying device according to claim 1,
The direction in which the plurality of stimulus applying means are arranged such that the distance between two stimulus applying means adjacent to each other is shorter on the front side of the helmet than on the rear side of the helmet Information notification device. In the direction information notifying device according to claim 1 or 2,
At least one of the plurality of stimulus applying means is arranged at a position corresponding to a median surface of a wearer of the helmet inside the helmet.

Images