Structure and haptic presentation device

Abstract

A structure according to an embodiment of the present technology includes a housing, a pressure generating device, and an acoustic metamaterial. The housing includes at least one or more opening portions. The pressure generating device is arranged in the shell and generates air pressure towards the opening part. And an acoustic metamaterial embedded in the opening portion and including a first through hole formed such that the air pressure linearly passes through the first through hole and a second through hole formed such that the air pressure spirally passes through the second through hole, the first through hole being formed such that the air pressure spirally passes through the first through hole, and the second through hole being formed such that the air pressure spirally passes through the second through hole. The acoustic metamaterial is formed such that a ratio of a sum of a cross-sectional area of the first through hole and a cross-sectional area of the second through hole to a cross-sectional area of the pressure generating device is less than 0.94.

Description

Technical Field

[0001] The present technology relates to a structural member and a tactile presentation device that can be used to provide tactile presentation and the like to a user. Background Art

[0002] Patent document 1 describes a subwoofer that includes a sound output unit disposed on an interior panel of a vehicle, a housing that is disposed in a gap between the interior panel and a frame of the vehicle and extends from the sound output unit toward a through hole formed in the frame, and a labyrinth portion that is disposed on the inner side of the housing. In the subwoofer, an opening portion that opens to the outside of the frame via the through hole is formed at an end portion of the housing on a side opposite to the sound output unit side, and the labyrinth portion includes a plurality of protrusions arranged in a staggered pattern so as to reduce the sound pressure level in a frequency band different from the frequency band of sound generated in the sound output unit among the frequency bands of sound that have penetrated into the housing. This is intended to reduce the influence of noise penetration (see paragraphs

[0027] to

[0031] of the specification of Patent document 1, Figure 5 wait).

[0003] Citation List

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-142552 Summary of the invention

[0006] Problem that the invention aims to solve

[0007] There is a need for a technology that can improve user immersion as described above.

[0008] In view of the above situation, the purpose of the present technology is to provide a structural component and a tactile presentation device that can enhance the user's sense of immersion.

[0009] Solution to the problem

[0010] In order to achieve the above-mentioned purpose, a structural member according to an embodiment of the present technology includes a shell, a pressure generating device and an acoustic metamaterial.

[0011] The housing includes at least one or more openings.

[0012] The pressure generating device is disposed in the housing and generates air pressure toward the opening.

[0013] The acoustic metamaterial is embedded in the opening portion and includes a first through hole and a second through hole, the first through hole is formed so that the air pressure passes through the first through hole linearly, the second through hole is formed so that the air pressure passes through the second through hole spirally, and the acoustic metamaterial is formed so that the ratio of the sum of the cross-sectional area of ​​the first through hole and the cross-sectional area of ​​the second through hole to the cross-sectional area of ​​the pressure generating device is less than 0.94.

[0014] This structural member includes a pressure generating device disposed in a housing and generating air pressure toward at least one or more openings, and an acoustic metamaterial embedded in the opening and including a first through hole and a second through hole, wherein the first through hole is formed so that air pressure passes through the first through hole in a straight line, the second through hole is formed so that air pressure passes through the second through hole in a spiral shape, and the acoustic metamaterial is formed so that the ratio of the sum of the cross-sectional area of ​​the first through hole and the cross-sectional area of ​​the second through hole to the cross-sectional area of ​​the pressure generating device is less than 0.94. This can improve the user's immersion.

[0015] The opening portion may be provided in a direction coaxial with a direction in which the air pressure is compressed by the pressure generating device.

[0016] The opening may be provided in an axial direction different from a direction in which the air pressure is compressed by the pressure generating device.

[0017] A sound absorbing material may be provided in the housing. In this case, the sound absorbing material may be formed of a laminate of fibers or a porous material.

[0018] The pressure generating device may include a voice coil motor or a fan.

[0019] The housing may include two or more openings. In this case, the acoustic metamaterial may be embedded in each of the openings.

[0020] The two or more opening portions may be opened in the same direction. In this case, the housing may include a partition provided between the opening portions.

[0021] The second through hole may have two or more angles.

[0022] The second through hole may be formed to have the two or more angles near an outlet through which the air pressure is discharged.

[0023] The acoustic metamaterial may include a magnetic circuit, and at least one or more of a cross-sectional area of ​​a passage connecting an inlet and an outlet of the second through hole, a length of the acoustic metamaterial in a direction coaxial with a direction in which the air pressure passes through the first through hole, or an angle formed by the passage is dynamically changed by driving the magnetic circuit.

[0024] The first passage may be cylindrical in shape. In this case, the second through hole may include a plurality of inlets and outlets.

[0025] A tactile presentation device according to an embodiment of the present technology includes: a shell, a pressure generating device and an acoustic metamaterial.

[0026] The housing includes at least one or more openings opened toward a user.

[0027] The pressure generating device is disposed in the housing and generates air pressure toward the opening.

[0028] The acoustic metamaterial is embedded in the opening portion and includes a first through hole and a second through hole, the first through hole is formed so that the air pressure passes through the first through hole linearly, the second through hole is formed so that the air pressure passes through the second through hole spirally, and the acoustic metamaterial is formed so that the ratio of the sum of the cross-sectional area of ​​the first through hole and the cross-sectional area of ​​the second through hole to the cross-sectional area of ​​the pressure generating device is less than 0.94. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] [ Figure 1 ] is a view schematically showing a wind speed generating device.

[0030] [ Figure 2 ] shows a graphic of a design based on acoustic metamaterials.

[0031] [ Figure 3 ] is a view schematically showing other examples of the wind speed generating device.

[0032] [ Figure 4 ] is a view showing a wind speed generating device including two opening portions.

[0033] [ Figure 5 ] is a schematic diagram showing another example of an acoustic metamaterial.

[0034] [ Figure 6 ] is a schematic diagram showing another example of an acoustic metamaterial. DETAILED DESCRIPTION

[0035] Hereinafter, embodiments according to the present technology will be described with reference to the drawings.

[0036] [Wind speed generating device]

[0037] Figure 1 2 is a view schematically showing a wind speed generating device 2 according to the present technology. Figure 1 A is a view schematically showing the housing 5 .

[0038] like Figure 1 As shown in FIG. 8A , the wind speed generating device 1 includes a shell 5 and an acoustic metamaterial 20 .

[0039] The housing 5 includes a voice coil motor 6 , a piston 7 , and an opening 10 .

[0040] In the voice coil motor 6, when voltage is applied, the vibration plate 8 of the piston 7 translates. Therefore, air is compressed from the vibration plate 8, pushing the air inside the housing 5 through the opening 10, and the air pressure is transmitted to the user, thereby presenting a tactile sensation.

[0041] Note that the driving amount of the vibration plate 8 is determined according to conditions depending on the content (such as the video the user is watching), etc. In other words, the wind speed corresponding to the scene of the content such as an explosion is sent to the user so that appropriate tactile presentation is performed in a non-contact manner.

[0042] In addition, a speaker or a fan motor can be used as the voice coil motor 6, but if the follow-up performance to the video changes is taken into consideration, the speaker shape is advantageous. In addition, air can be compressed by a pump or the like.

[0043] The opening 10 is provided in a direction coaxial with the direction of driving the piston 7 (the direction of arrow 2). In other words, the opening 10 is provided in a direction coaxial with the direction formed by the main propagation direction of the air pushed by the piston 7. In addition, in the present embodiment, the acoustic metamaterial 20 is embedded in the opening 10. The acoustic metamaterial 20 is a structural member having different acoustic impedances in the outer peripheral portion and the central portion.

[0044] Figure 1 B is a view schematically showing an inlet of the acoustic metamaterial 20 . Figure 1 C is a view schematically showing a cross-sectional view of the acoustic metamaterial 20 and a traveling direction of wind.

[0045] Please note that the entrance refers to Figure 1 The portion of the housing 5 shown in A facing the interior of the housing 5. In other words, the inlet refers to the hole through which air or sound enters. Similarly, the outlet refers to the Figure 1 A is a portion facing the outside of the housing 5. In other words, the outlet refers to a hole from which air or sound leaves.

[0046] like Figure 1 As shown in Figures B and C, the acoustic metamaterial 20 includes a central portion 21 and a peripheral portion 22. The outlet of the acoustic metamaterial 20 has a Figure 1 The inlet is similar in shape to that shown in B. In other words, Figure 1 In case B, the spiral portion 23 of the peripheral portion 22 includes six inlets and also includes six outlets.

[0047] The center portion 21 has a hole parallel to the traveling direction of air or sound (the direction of arrow 25). In the present embodiment, the center portion 21 has a cylindrical shape, and the shapes of the inlet and the outlet are formed in a circular shape. It should be noted that the shape of the center portion 21 is not limited and may be an ellipse, etc., the cross-sectional areas of the inlet and the outlet may be different from each other, such as a triangular pyramid, etc., or the shapes of the inlet and the outlet may be different from each other.

[0048] In addition, if Figure 1 As shown in FIG. 2C, each spiral portion 23 of the outer peripheral portion 22 includes a passage 24 connecting an inlet and an outlet. The passage 24 is formed to have a spiral shape (spiral structure), and air or sound passing through the passage 24 moves in a spiral shape.

[0049] Please note that Figure 1 The thickness t shown in C of FIG. 2 represents the length of the acoustic metamaterial 20 in the traveling direction of air or sound (the direction of arrow 25 ). In the present embodiment, the thickness t is assumed to be 0.5 mm based on actual design limitations.

[0050] in addition, Figure 1 An angle φ shown in C represents the angle of the passage 24. In the present embodiment, the angle of the passage 24 refers to an angle defined by a plane 26 perpendicular to the direction of thickness t (direction of arrow 25) and the traveling direction of air or sound.

[0051] The acoustic metamaterial 20 includes a central portion 21 having a cylindrical shape and a spiral portion 23 having a spiral shape, so that the wind speed generated from the piston 7 can be rectified. This can improve the straight-line travel characteristics of the air and also reduce the sound pressure.

[0052] Therefore, since the driving direction of the piston 7 is in the coaxial direction with the direction defined by the main direction of air propagation, the wind traveling straight from the piston 7 blows directly toward the user, which can adapt to changes corresponding to the scene of the content based on the specific situation.

[0053] Note that in the present embodiment, the voice coil motor 6 and the piston 7 are used as a pressure generating device that generates air pressure.

[0054] It should be noted that in this embodiment, the central portion 21 corresponds to the first through hole.

[0055] It should be noted that in this embodiment, the spiral portion 23 corresponds to the second through hole.

[0056] Note that in this embodiment, the angle φ corresponds to the angle defined by the passageway.

[0057] Figure 2 A diagram showing a design based on an acoustic metamaterial 20 is shown.

[0058] Figure 2A is a graph showing the contrast between the presence and absence of the acoustic metamaterial 20 . Figure 2 B is a graph showing the relationship between the sound absorption frequency f in the thickness t and the angle φ of the passage 24 . Figure 2 C is a graph showing the specific exhaust efficiency in each setting.

[0059] Figure 2 A shows a graph 30 to which the acoustic metamaterial 20 is not applied and a graph 31 to which the acoustic metamaterial is applied.

[0060] like Figure 2 As shown in A of FIG. 1 , the horizontal axis represents frequency (Hz) and the vertical axis represents sound pressure (dB). In the present embodiment, when the vibration plate 8 is driven at 1 m / s, the sound pressure at a position 100 mm away from the center of the opening 10 is calculated.

[0061] The descending parts in the graphs 30 and 31 indicate that the sound pressure is reduced due to the occurrence of resonance. In addition, the line 32 indicates the frequency condition of reducing the sound pressure when the thickness of the acoustic metamaterial 20 is 10 mm. In addition, the line 33 indicates the frequency condition of reducing the sound pressure when the thickness of the acoustic metamaterial 20 is 15 mm. It should be noted that the peaks of the graphs 30 and 31 deviate in some parts because the standing wave deviates due to the embedded acoustic metamaterial 20.

[0062] In other words, the acoustic metamaterial 20 is fitted in the opening 10, thereby reducing the sound pressure of the air pushed from the piston 7. Note that in the present embodiment, the tactile sensation presentation by the air supply provided to the user is for sounds in a frequency band of 1 kHz or less.

[0063] The sense of touch can be delivered to the user by using air, and also provides a sound-deadening effect.

[0064] like Figure 2 As shown in B, the horizontal axis represents the angle of the passage 24, and the vertical axis represents the frequency (Hz) of the sound absorption frequency. In this embodiment, it is assumed that the user (the target to whom the tactile sensation is presented using air) is located 100 mm in front of the wind speed generating device 1. In this case, in order to provide sufficient tactile presentation to the user, the wind speed generating device 1 requires the flow velocity at the position 100 mm in front to be 5 m / s or higher.

[0065] In the present embodiment, the acoustic metamaterial 20 is embedded in the opening 10 , and therefore the spiral shape of the outer peripheral portion 22 increases the straight-line travel property of the air and also enhances the straight-line travel property of the air passing through the central portion 21 .

[0066] Figure 2 The C is shown in Figure 1A shows a graph comparing the degree of increase in wind speed at a position 100 mm in front between a wind speed generating device X including an opening portion 10 provided in a shell 5, a double-hole wind speed generating device Y including a new opening portion provided on the back side of a vibration plate 8 (facing the opening portion 10), and a wind speed generating device Z including an acoustic metamaterial 20 respectively embedded in the two opening portions.

[0067] like Figure 2 As shown in C, the simulation shows that, assuming that the wind speed at a position 100 mm in front of the wind speed generating device X is 1, the wind speed in the wind speed generating device Y becomes 2 times, and the wind speed in the wind speed generating device Z is 1.25 times higher per opening.

[0068] In addition, assuming that the speed of sound is constant, the vanishing frequency f in the acoustic metamaterial is determined based on the angle (φ) and thickness t of the spiral shape, and the following equation is obtained.

[0069] f = C0 / λ = C0Nsin(φ) / 2t

[0070] C0 represents the speed of sound. In addition, N represents an integer, which means that the sound pressure decreases by an integer multiple.

[0071] In addition, the sound absorption ratio in the acoustic metamaterial is determined by the radius r1 of the central portion 21 and the radius r2 of the peripheral portion 22 including the spiral portion 23, and the following equation is obtained (see Figure 1 B).

[0072] Z2 / Z1 = πr1^2 / t(r2 - r1)

[0073] Here, Z1 represents the acoustic impedance of the spiral portion 23 , and Z2 represents the acoustic impedance of the central portion 21 .

[0074] If the above ratio of acoustic impedances is infinite, the sound absorption effect decreases. In other words, the frequency is determined by the angle of the spiral portion 23 and the thickness of the acoustic metamaterial, and the amount of reduction in sound pressure is determined by the ratio of acoustic impedances.

[0075] exist Figure 2 In B, since the frequency band in this embodiment is 1 kHz or less, a target region 35 of the sound absorption frequency f is set. It should be noted that the sound absorption frequency refers to the sound frequency reduced by the acoustic metamaterial 20. Figure 2 As shown in FIG. 1B , the sound absorption frequency f and the angle φ of the passage 24 are respectively shown when the thickness of the acoustic metamaterial 20 is 10 mm, 30 mm, and 50 mm.

[0076] in addition, Figure 2The area 36 shown in B of FIG. 3 refers to the practically designable angle of the passage 24. In other words, if the angle φ is too large, it is difficult to achieve practical design due to the thickness of the acoustic metamaterial 20, the number of rotations of the spiral portion 23, etc. In other words, in the present embodiment, the angle φ of the passage 24 of the acoustic metamaterial 20 takes a value less than 15 degrees.

[0077] The wind speed around the outlet of the acoustic metamaterial 20 obtained in the simulation is 10 m / s, and the inner diameter (the diameter of the center portion 21 ) of the acoustic metamaterial 20 is set to 20 mm, so that the flow speed can be defined.

[0078] Here, assuming that the actual design limit thickness of the acoustic metamaterial 20 is 0.5 mm, as a configuration for achieving the effect of the present invention in a hearing range of 20 kHz or less, the ratio R of the cross-sectional area S' of the acoustic metamaterial 20 to the effective area S of the wind speed generating device 1 is determined by the following equation.

[0079] R = S' / S = (r1^2π+(r2^2―r1^2)0.5π) / S < 0.94

[0080] Here, the effective cross-sectional area S represents the area of ​​the vibration plate 8 including the edge portion 38 of the piston 7 (see Figure 1 In addition, the cross-sectional area S′ represents an area obtained by adding the area of ​​the outlet of the central portion 21 and the area of ​​the outlet of the spiral portion 23.

[0081] In other words, in the present embodiment, the ratio of the cross-sectional area S′ to the effective cross-sectional area S of the acoustic metamaterial 20 is designed to be 0.94 or less.

[0082] Figure 3 2 is a diagram schematically showing another example of the wind speed generating device 40 .

[0083] Figure 3 A is the position of the opening 10 is different from that in Figure 1 A view of the position of the wind speed generating device 1 shown in FIG. Figure 3 As shown in FIG. 1A , the wind speed generating device 40 includes an opening 10 in an axial direction different from the driving direction (direction of arrow 41 ) of the piston 7 . Therefore, changing the positional relationship of the wind outlet can save space for the device including the wind speed generating device 40 .

[0084] Figure 3 B is a view of the wind speed generating device 50 to which the sound absorbing material 45 is added. Figure 3As shown in FIG. 1B , the wind speed generating device 50 includes a sound absorbing material 45 on the wall surface inside the housing 51. For example, the sound absorbing material 45 is formed of a porous material or a structure on which fibers are folded. This can reduce the sound pressure on the high-frequency side. It should be noted that the position where the sound absorbing material 45 is set, the number of sound absorbing materials 45, the material, etc. are not limited.

[0085] In addition, in addition to the above example, the power unit of the voice coil motor 6 and the piston 7 may be a fan motor. Even in a configuration with high drive responsiveness to the angle change of the blade portion, etc., the sound pressure of the wind can be reduced. Note that in this case, the effective cross-sectional area S is the area formed by the propeller portion of the fan. In other words, the effective cross-sectional area S is the sum of the cross-sectional areas of the plurality of blades constituting the propeller portion.

[0086] Figure 4 1 is a diagram showing a wind speed generating device including two openings. Figure 4 A schematically shows the wind speed generating device 60 . Figure 4 B is a view showing the flow of air exhausted from the wind speed generating device 60 . Figure 4 C shows a top view and a cross-sectional view of the wind speed generating device 60 .

[0087] like Figure 4 As shown, two openings 10 are provided in two directions of the driving direction of the vibration plate 8. Hereinafter, the direction of the arrow 61 driving the vibration plate 8 is referred to as the downward direction, and the direction of the arrow 62 is referred to as the upward direction. In addition, the downward chamber inside the housing 5 separated by the piston 7 is referred to as the inner chamber A, and the upward chamber is referred to as the inner chamber B.

[0088] like Figure 4 As shown in FIG. 1A , the wind speed generating device 60 includes an opening portion 10 a for discharging the air pushed by the vibration plate 8 from the inner chamber A and an opening portion 10 b for discharging the air pushed by the vibration plate 8 from the inner chamber B.

[0089] although Figure 4 Although not shown in the figure, the acoustic metamaterial 20 is respectively embedded in the opening portion 10a and the opening portion 10b.

[0090] Note that, in general, the thickness of the opening 10 (the length in the direction perpendicular to the driving direction of the piston 7) is substantially consistent with the thickness of the acoustic metamaterial 20. If not consistent, the acoustic metamaterial 20 protrudes from the opening 10 to the inside of the housing 5 or the outside of the housing 5. In this case, it is possible to arbitrarily set whether the acoustic metamaterial 20 protrudes to the inside of the housing 5 or the outside of the housing 5. For example, in the case of the inner chamber A, if the position of the acoustic metamaterial 20 is limited by the voice coil motor 6, the acoustic metamaterial 20 may protrude to the outside of the housing 5.

[0091] like Figure 4 As shown in FIG. 1B , the vibration plate 8 is driven in the up-down direction so that air is discharged from the openings 10a and 10b. Figure 2 As shown in FIG. 3C , embedding the acoustic metamaterial 20 in the two openings 10 can improve the exhaust efficiency and present air to the user located 100 mm in front at a flow rate of 5 m / s or more.

[0092] In addition, the partition 63 is provided between the opening 10a and the opening 10b outside the housing 5 of the wind speed generating device 60. The partition 63 rectifies the air discharged from the opening 10a and the opening 10b. This can improve the straight-line travel characteristics of the air. In addition, the acoustic metamaterial 20 is embedded in the two openings 10, which can reduce the sound pressure when the exhaust pressure part is used for the wind speed.

[0093] Figure 5 is a schematic diagram showing another example of the acoustic metamaterial 70 . Figure 5 FIG. 8A shows a top view of the acoustic metamaterial 70 . Figure 5 B and C show cross-sectional views of the acoustic metamaterial 70 .

[0094] Figure 5 The acoustic metamaterial 70 is shown when the spiral portion 71 has two or more angles. In the present embodiment, the spiral portion 71 near the outlet 72 of the acoustic metamaterial 70 has two or more angles.

[0095] A difference in acoustic impedance due to the spiral structure occurs, which worsens the amount of reduction in sound pressure, but can improve the straight-line travel characteristics of wind.

[0096] Note that two or more angles of the spiral portion 71 may be formed from the inlet. In addition, the passage of the spiral portion 71 may be driven to dynamically change the angle.

[0097] Figure 6 is a schematic diagram showing another example of an acoustic metamaterial 80 .

[0098] like Figure 6 As shown, the acoustic metamaterial 80 includes a magnet 82 fixed to cover an outer peripheral portion 81 , a dynamically driven coil 83 , a fixed coil 84 , a metal 86 provided to a spiral portion 85 , and a magnet 87 provided inside the acoustic metamaterial 80 .

[0099] exist Figure 6 , the acoustic metamaterial 80 includes a magnetic circuit as described above. The magnetic circuit is driven in the direction of arrow 88, so that the thickness of the passage of the spiral portion 85 (the length in the direction perpendicular to the direction of air flowing through the passage), the thickness t of the acoustic metamaterial 80 (the length in the direction coaxial with the direction 89 of the air), and the angle φ of the passage are dynamically changed.

[0100] This can form a shape of the acoustic metamaterial that corresponds to and is suitable for the frequency generated from the voice coil motor 6 .

[0101] In the above, the wind speed generating device 1 according to the present embodiment includes: a housing 5 including at least one or more openings 10; a voice coil motor 6 and a piston 7, which are arranged in the housing 5 and generate air pressure toward the opening 10; and an acoustic metamaterial 20, which is embedded in the opening 10 and includes a central portion 21 and a spiral portion 23, the central portion 21 is formed so that the air pressure passes through the central portion 21 linearly, the spiral portion 23 is formed so that the air pressure passes through the spiral portion 23 spirally, and the acoustic metamaterial 20 is formed so that the ratio of the sum of the cross-sectional area of ​​the central portion 21 and the cross-sectional area of ​​the spiral portion 23 to the effective cross-sectional area of ​​the piston 7 is less than 0.94. This can improve the user's immersion.

[0102] Conventionally, in tactile presentation by non-contact means, wind is provided to the user in combination with scenes such as explosions. Ultrasonic waves are used as an example of a non-contact means, but are difficult to use in practice due to the risk of direct contact with the eardrum. In addition, when air is sent, noise corresponding to the wind speed is generated due to the discharge pressure, and therefore, the sound of the content may be disturbed. In particular, in the case of small devices such as those used in homes, anti-noise measures do not result in insufficient output due to the lack of wind output.

[0103] In addition, as an anti-noise measure, as a characteristic of the sound absorbing material, the sound absorbing material is used in a bandwidth of 1 kHz or more. On the other hand, when the sense of touch is presented by blowing air, it is operated in a frequency band of 1 kHz or less. Therefore, it is difficult to mute the sound by using the sound absorbing material. In addition, in the case of a structure that cancels out the sounds, when targeting a low frequency band, the design size becomes large due to the length of the wavelength, so the portability is reduced.

[0104] In the present technology, an acoustic metamaterial is embedded in an opening portion, and the acoustic metamaterial includes: a first through hole, which is formed so that air pressure passes through the first through hole in a straight line, and a second through hole, which is formed so that air pressure passes through the second through hole in a spiral shape. In addition, the acoustic metamaterial is formed so that the ratio of the cross-sectional area of ​​the acoustic metamaterial to the effective cross-sectional area of ​​the pressure generating device is less than 0.94. Therefore, by using the second through hole having a spiral shape, a difference in air pressure drop is provided, and the straight-line travel characteristics of the wind passing through the first through hole are improved. In addition, the structure formed by the first through hole that allows air pressure to travel in a straight line and the second through hole having a spiral shape also provides a sound-absorbing effect.

[0105] It should be noted that the effects described in this disclosure are not restrictive but merely illustrative, and other effects may be provided. The description of multiple effects does not mean that these effects are not necessarily produced at the same time. This means that at least any of the above effects is obtained according to the conditions, etc., and of course, effects not described in this disclosure may also be produced.

[0106] At least two of the characteristic portions according to the above-described embodiments can be combined. In other words, the various characteristic portions described in the embodiments can be arbitrarily combined without distinguishing between the embodiments.

[0107] Note that the present technology can also adopt the following configurations.

[0108] (1) A structural member comprising:

[0109] a housing, the housing comprising at least one or more openings;

[0110] a pressure generating device disposed in the housing and generating air pressure toward the opening; and

[0111] An acoustic metamaterial is embedded in the opening and includes

[0112] a first through hole formed so that the air pressure passes through the first through hole in a straight line, and

[0113] A second through hole is formed so that the air pressure spirally passes through the second through hole, and the acoustic metamaterial is formed so that the ratio of the sum of the cross-sectional areas of the first through hole and the second through hole to the cross-sectional area of ​​the pressure generating device is less than 0.94.

[0114] (2) The structural member according to (1), wherein:

[0115] The opening is provided in a direction coaxial with a direction in which the air pressure is compressed by the pressure generating device.

[0116] (3) The structural member according to (1), wherein:

[0117] The opening is provided in an axial direction different from a direction in which the air pressure is compressed by the pressure generating device.

[0118] (4) The structural member according to (1), wherein:

[0119] a sound absorbing material disposed in the housing, and

[0120] The sound absorbing material is formed of a laminate of fibers or a porous material.

[0121] (5) The structural member according to (1), wherein:

[0122] The pressure generating device includes a voice coil motor or a fan.

[0123] (6) The structural member according to (1), wherein:

[0124] The housing includes two or more openings, and

[0125] The acoustic metamaterial is embedded in each of the openings.

[0126] (7) The structural member according to (6), wherein:

[0127] The two or more openings open in the same direction, and

[0128] The housing includes a partition disposed between the opening portions.

[0129] (8) The structural member according to (1), wherein:

[0130] The second through hole has two or more angles.

[0131] (9) The structural member according to (8), wherein:

[0132] The second through hole is formed to have the two or more angles near an outlet through which the air pressure is discharged.

[0133] (10) The structural member according to (1), wherein:

[0134] The acoustic metamaterial includes a magnetic circuit, and

[0135] At least one or more of a cross-sectional area of ​​a passage connecting an inlet and an outlet of the second through hole, a length of the acoustic metamaterial in a direction coaxial with a direction in which the air pressure passes through the first through hole, or an angle formed by the passage is dynamically changed by driving of the magnetic circuit.

[0136] (11) The structural member according to (1), wherein:

[0137] The first passage is cylindrical in shape, and

[0138] The second through hole includes a plurality of inlets and outlets.

[0139] (12) A tactile presentation device, comprising:

[0140] A housing, the housing comprising at least one or more openings opening toward a user;

[0141] a pressure generating device disposed in the housing and generating air pressure toward the opening; and

[0142] An acoustic metamaterial is embedded in the opening and includes

[0143] a first through hole formed so that the air pressure passes through the first through hole in a straight line, and

[0144] A second through hole is formed so that the air pressure spirally passes through the second through hole, and the acoustic metamaterial is formed so that the ratio of the sum of the cross-sectional areas of the first through hole and the second through hole to the cross-sectional area of ​​the pressure generating device is less than 0.94.

[0145] Reference Mark List

[0146] 1. Wind speed generating device

[0147] 5 Shell

[0148] 6 Voice Coil Motor

[0149] 7 Piston

[0150] 10 Opening

[0151] 20Acoustic metamaterials

[0152] 21 Center

[0153] 23 Helix

Claims

1. A structural member, comprising: a housing, the housing comprising at least one or more openings; a pressure generating device, the pressure generating device being disposed in the housing and generating air pressure toward the opening; as well as An acoustic metamaterial is embedded in the opening and includes a first through hole formed so that the air pressure passes through the first through hole in a straight line, and A second through hole is formed so that the air pressure spirally passes through the second through hole, and the acoustic metamaterial is formed so that the ratio of the sum of the cross-sectional area of ​​the first through hole and the cross-sectional area of ​​the second through hole to the cross-sectional area of ​​the pressure generating device is less than 0.

94.

2. The structural member according to claim 1, wherein: The opening is provided in a direction coaxial with a direction in which the air pressure is compressed by the pressure generating device.

3. The structural member according to claim 1, wherein: The opening is provided in an axial direction different from a direction in which the air pressure is compressed by the pressure generating device.

4. The structural member according to claim 1, wherein: A sound absorbing material is disposed within the housing, and The sound absorbing material is formed of a laminate of fibers or a porous material.

5. The structural member according to claim 1, wherein: The pressure generating device includes a voice coil motor or a fan.

6. The structural member according to claim 1, wherein: The housing includes two or more openings, and The acoustic metamaterial is embedded in each of the openings.

7. The structural member according to claim 6, wherein: The two or more openings open in the same direction, and The housing includes a partition disposed between the opening portions.

8. The structural member according to claim 1, wherein: The second through hole has two or more angles.

9. The structural member according to claim 8, wherein: The second through hole is formed to have two or more angles near an outlet through which the air pressure is discharged.

10. The structural member according to claim 1, wherein: The acoustic metamaterial includes a magnetic circuit, and By driving the magnetic circuit, at least one or more of the cross-sectional area of ​​the passage connecting the inlet and the outlet of the second through hole, the length of the acoustic metamaterial in a direction coaxial with the direction in which the air pressure passes through the first through hole, or the angle formed by the passage are dynamically changed.

11. The structural member according to claim 1, wherein: The first passage is cylindrical in shape, and The second through hole includes a plurality of inlets and outlets.

12. A tactile presentation device, comprising: A housing, the housing comprising at least one or more openings opening toward a user; a pressure generating device, the pressure generating device being disposed in the housing and generating air pressure toward the opening; as well as An acoustic metamaterial is embedded in the opening and includes a first through hole formed so that the air pressure passes through the first through hole in a straight line, and A second through hole is formed so that the air pressure spirally passes through the second through hole, and the acoustic metamaterial is formed so that the ratio of the sum of the cross-sectional area of ​​the first through hole and the cross-sectional area of ​​the second through hole to the cross-sectional area of ​​the pressure generating device is less than 0.94.

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