Stimulation device, stimulation method, and installation body

Abstract

To provide a stimulation device that increases the reproducibility of increased sensory sensitivity.SOLUTION: A stimulation device 10 includes a stimulating part 14 which gives a stimulus to the inside of a human body from a predetermined region P1 in a surface of a human body. The stimulating part 14 is located at a position where a ratio ΔD2 / D1 is equal to or less than a first threshold, wherein D1 is the distance from a first tissue B1, which is harder than a second tissue B2, both being contained inside the human body, to the stimulating part 14, and ΔD2 is the amount of variation in thickness D2 of the relatively soft second tissue B2 located between the first tissue B1 and the predetermined site P1 relative to D1.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a stimulation device, a stimulation method, and a wearable device. [Background technology]

[0002] Conventionally, there are known techniques for improving sensory sensitivity by utilizing the stochastic resonance phenomenon. Hereinafter, sensory sensitivity includes tactile sensitivity and somatosensory sensitivity. For example, Patent Document 1 discloses a method for improving braking operation compared to conventional methods by attaching a vibration pad that generates weak vibrations to the upper surface of a brake pedal to improve the tactile sensitivity of the sole of the driver's foot when decelerating the car. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-138764 A Summary of the Invention [Problem to be solved by the invention]

[0004] There is room for improvement in conventional technology. For example, the reproducibility of the effect of increasing sensory sensitivity obtained through the phenomenon of stochastic resonance was low.

[0005] In view of the above, an object of the present disclosure is to improve the reproducibility of improved sensory sensitivity. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, a stimulation device according to a first aspect comprises: A stimulation unit that applies a stimulation to an inside of the human body from a predetermined site on a surface of the human body, The stimulation unit is positioned at a position where the ratio of the amount of variation in thickness of the second tissue, which is relatively soft and located between the first tissue and the specified location, to the distance from the first tissue, which is relatively hard among the first tissue and second tissue contained inside the human body, to the stimulation unit is equal to or less than a first threshold value.

[0007] Alternatively, a stimulation method according to a second aspect includes: The method includes a step of applying a stimulus to the inside of the human body from a lateral position shifted along the contour of the finger from the apex on the back side of the hand on the cut surface of the finger on the surface of the finger.

[0008] Alternatively, the mounting body according to the third aspect comprises: A ring-shaped housing that surrounds an area into which a user's finger can be inserted, The housing includes: an inner wall including a first portion that contacts or is close to a vertex of the cut surface of the finger on the back side of the hand when the finger is inserted into the region, and a second portion that is located at a position different from the first portion; and a stimulation unit located in the second portion and configured to provide a stimulation to the finger. Effect of the Invention

[0009] According to the stimulation device, stimulation method, and wearing body according to one embodiment of the present disclosure, it is possible to improve the reproducibility of the improvement in sensory sensitivity. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic diagram showing an example of the configuration of a wearing body having a stimulation device according to a first embodiment of the present disclosure. FIG. [Diagram 2] FIG. 2 is a cross-sectional view taken along the line II-II of FIG. [Diagram 3] 2 is a block diagram showing an example of the configuration of the stimulation device of FIG. 1. [Figure 4] 3 is a schematic diagram showing an example of the arrangement of a stimulation unit of the stimulation device of FIG. 2. [Diagram 5] 13 is a schematic diagram showing an example of an arrangement of a stimulation section of a stimulation device according to a second embodiment of the present disclosure. FIG. [Figure 6] FIG. 13 is a schematic diagram showing an example of an arrangement of a stimulation unit of a stimulation device according to a third embodiment of the present disclosure. [Figure 7] FIG. 1 is a first diagram for explaining the effect of the present disclosure. [Figure 8] FIG. 2 is a second diagram for explaining the effect of the present disclosure. [Figure 9] FIG. 3 is a third diagram for explaining the effect of the present disclosure. [Figure 10] FIG. 4 is a fourth diagram for explaining the effect of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Conventionally, a stochastic resonance phenomenon has been known in which, in a nonlinear system such as a bistable system or a threshold system, adding a weak noise below a threshold to a signal increases the probability that the signal will exceed the threshold and become stronger, thereby improving the ability to detect weak signals. As an example, it is known that adding a weak vibration that is not felt by the user improves the tactile sensitivity of parts of the human body, including fingers, hands, and feet.

[0012] For example, tactile sensitivity can be examined based on the two-point discrimination threshold, the minimum distance at which mechanical stimuli can be distinguished as being from separate stimuli when applied to two points on the skin. It is known that applying a weak vibration that the user cannot feel makes the two-point discrimination threshold smaller, i.e., makes the sense of touch more sensitive. This effect can also be obtained by placing a vibrator that generates a weak vibration on a tool that the user holds.

[0013] According to the method described in Patent Document 1, the driver's tactile sensitivity is improved by weak vibrations. This is a fact known as the stochastic resonance phenomenon. When the stochastic resonance phenomenon is applied to fingertips, it is necessary to efficiently transmit the weak vibrations that excite the stochastic resonance phenomenon to the sensory organs of the fingertips. In past reports, vibrators were attached to locations such as the side of the fingertip, the tip of the nail, near the fingertip, and the base of the finger.

[0014] For example, if a vibrator is attached near the fingertip, it is likely to interfere with objects when touching them, making it difficult to move the fingertip. To address this issue, for example, it is possible to attach a vibrator to the base of the finger or to use a ring-shaped wearable device with a vibrator attached.

[0015] In this case, as described later, it was found that if the vibrator is attached to a position closer to the base of the finger than the tip, for example, between the first and third joints, directly above the back of the finger, a large variation occurs in the vibration pattern transmitted to the fingertip. Therefore, when the vibrator is attached to this position, it is not easy to suppress the variation in the effect of improving sensory sensitivity due to the stochastic resonance phenomenon and to express the effect with good reproducibility.

[0016] The present disclosure relates to improving sensory sensitivity by utilizing the stochastic resonance phenomenon, and is for effectively improving sensory sensitivity by using stochastic resonance while maintaining the original sensory sensitivity of the user. The present disclosure aims to improve the reproducibility of the improvement in sensory sensitivity obtained by the stochastic resonance phenomenon. The present disclosure is for effectively improving sensory sensitivity by using stochastic resonance by reducing the variation based on the wearing state of the vibrator attached to the user's fingers, feet, etc.

[0017] An embodiment of the present disclosure will be mainly described below with reference to the accompanying drawings.

[0018] (First embodiment) Fig. 1 is a schematic diagram showing an example of the configuration of a wearing body 1 having a stimulation device 10 according to a first embodiment of the present disclosure. With reference to Fig. 1, an example of the configuration and function of the wearing body 1 having the stimulation device 10 according to the first embodiment will be mainly described.

[0019] The wearing body 1 has a stimulation device 10. The wearing body 1 has an annular housing 20 to which the stimulation device 10 is attached and which surrounds a part of the human body. The housing 20 has an annular structure which surrounds an area into which a user's finger can be inserted. The wearing body 1, when worn on a part of the human body via the housing 20, applies a stimulus to the part of the human body using the stimulation device 10.

[0020] In the present disclosure, "a part of the human body" includes fingers such as the index finger and thumb, the palm, the back of the hand, the arm, the ankle, the sole, and other parts of the foot. "Stimulation" includes weak vibrations that do not exceed the threshold of sensation of the user. The level that does not exceed the threshold of sensation of the user means, for example, a level that the user cannot perceive. The weak vibration has, for example, a frequency characteristic similar to that of white noise.

[0021] In the first embodiment shown in FIG. 1, as an example, the wearing body 1 is worn on the index finger of the hand. The wearing body 1 is located between a first joint located on the most distal end side of the index finger of the hand and a second joint located next to the first joint on the back side of the hand from the first joint. The housing 20 has an annular structure surrounding at least a part of the finger. For example, when the housing 20 is attached to the finger, it surrounds only substantially the entire finger side and finger back between the finger pad and the finger back along the outer periphery of the finger, exposing a part of the finger pad. The housing 20 does not surround the entire outer periphery of the finger, but exposes a part of the finger pad. As a result, when the user holds and uses a tool, the wearing body 1 does not prevent contact between the tool and the skin of the finger pad, making it easier for the user to operate the tool.

[0022] The housing 20 has an insertion section 21 formed of a space into which a finger is inserted. The housing 20 has a frame section 22 surrounding the insertion section 21. The housing 20 has a first portion 22a located at the apex of the frame section 22, which contacts or is close to the apex of the finger on the back side of the hand located at the back of the finger when the housing 20 is attached to the finger. The housing 20 has a second portion 22b formed at a position different from the first portion 22a in the frame section 22. The second portion 22b is formed at a position shifted from the apex of the frame section 22 to the side side along the contour of the frame section 22. The second portion 22b is located on the side of the finger when the housing 20 is attached to the finger.

[0023] The wearable body 1 is configured by attaching the stimulation device 10 to a ring-shaped housing 20. For example, the stimulation device 10 is attached to the second part 22b of the housing 20. When a user wears the wearable body 1 as a ring-shaped device on his / her index finger, a vibrator (described later) included in the stimulation device 10 is arranged in contact with a predetermined part on the side of the finger where the second part 22b is located. In the present disclosure, the "predetermined part" is, for example, a part on the surface of the human body, and includes a part on the surface of the skin where a stimulation is applied to the inside of the human body from the vibrator included in the stimulation device 10.

[0024] The vibrator of the stimulation device 10 included in the wearable body 1 is disposed between the first and second joints of the fingers of the hand. The vibrator is installed as part of the stimulation device 10 in a ring-shaped housing 20. A user receives vibrations from the vibrator by wearing such a ring-shaped wearable body 1. By wearing the wearable body 1 between the first and second joints, the user can touch an object with the fingertips without the wearable body 1 and the object interfering with each other.

[0025] Fig. 2 is a cross-sectional view taken along the line II-II of Fig. 1. Fig. 2 is a schematic cross-sectional view of the attachment 1 taken along the line II-II of Fig. 1.

[0026] The first portion 22a is formed flat, unlike other components such as the second portion 22b located on the inner surface side of the housing 20. This allows the user to attach the housing 20 to the finger by aligning the flat first portion 22a with the back of the finger, and the user can easily wear the wearing body 1. The flat first portion 22a improves the accuracy of the user's positioning of the first portion 22a relative to the back of the finger. This positioning allows the vibrator included in the stimulation device 10 to be more reliably placed in contact with a predetermined portion of the side of the finger.

[0027] The stimulator 10 having a vibrator is attached to the second part 22b, not the first part 22a, of the housing 20. Therefore, when the wearing body 1 is worn on a finger, the vibrator is placed in contact with a predetermined part of the side of the finger that is inclined at a predetermined angle from a straight line connecting the back of the finger and the pad of the finger, rather than directly above the finger, i.e., at the apex of the finger on the back side of the hand located at the back of the finger.

[0028] The housing 20 has a third portion 22c located on the opposite side of the second portion 22b with respect to the first portion 22a. On the cross section shown in Fig. 2, a pair of inner side surfaces inclined obliquely from both sides of the first portion 22a of the housing 20 have different angles of inclination with respect to the first portion 22a. For example, a gradient line L1 of the inner side surface of the third portion 22c inclined obliquely from the left side of the first portion 22a and a gradient line L2 of the inner side surface of the second portion 22b inclined obliquely from the right side of the first portion 22a are not line-symmetrical with each other but are asymmetrical.

[0029] The inner surface of the third portion 22c is inclined so as to be linearly symmetrical with the stimulating device 10 having a vibrator, centered on the central axis of the ring-shaped housing 20. That is, the inclination of the stimulating device 10 with respect to the first portion 22a and the inclination of the inner surface of the third portion 22c with respect to the first portion 22a are mutually symmetrical. As a result, when the ring-shaped housing 20 is attached to the finger, the vibrator of the stimulating device 10 is naturally arranged at a position and inclination that is linearly symmetrical with the inner surface of the third portion 22c on the cut surface of the finger. On the other hand, the stimulating device 10 having a vibrator is attached to the housing 20 in a state where it does not match the inclination of the inner surface of the second portion 22b, but is slightly inclined with respect to the inner surface.

[0030] The housing 20 further has a fourth portion 22d extending from each of the second portion 22b and the third portion 22c toward the finger pad side when the housing 20 is attached to the finger. The fourth portion 22d extends from an end of the second portion 22b located opposite the first portion 22a toward the inside of the insertion portion 21 while gently bending in an R shape. The fourth portion 22d extends from an end of the third portion 22c located opposite the first portion 22a toward the inside of the insertion portion 21 while gently bending in an R shape. The fourth portion 22d formed on the second portion 22b side and the fourth portion 22d formed on the third portion 22c side have mutually symmetrical shapes and arrangements.

[0031] The second portion 22b and the fourth portion 22d formed on the second portion 22b side have a lower rigidity than the first portion 22a. The third portion 22c and the fourth portion 22d formed on the third portion 22c side have a lower rigidity than the first portion 22a. The entire portion of the housing 20 formed at a position shifted from the first portion 22a to the side along the contour of the frame portion 22 has a lower rigidity than the first portion 22a, thereby realizing a spring structure in the portion. The second portion 22b, the third portion 22c, and the fourth portion 22d have a spring structure, which improves the fit when the housing 20 is fitted on a finger. The user can easily fit the housing 20 on his / her finger. In addition, even if the thickness of the finger differs from user to user, the housing 20 can change the width of the spatial area of ​​the insertion portion 21 according to the change in the thickness of the finger, and the fit can be maintained.

[0032] The housing 20 has the second portion 22b and the third portion 22c extending from the first portion 22a so as to widen toward the outside of the insertion portion 21, so that the second portion 22b and the third portion 22c become wider toward the finger pad side. On the other hand, the housing 20 has the fourth portion 22d bent toward the inside of the insertion portion 21 so that the fourth portion 22d becomes narrower toward the finger pad side.

[0033] The housing 20 has an inner wall 221 that constitutes the inside of the frame portion 22. The inner wall 221 includes the above-mentioned first portion 22a that contacts or is close to the apex of the cut surface of the finger on the back side of the hand when the user's finger is inserted into the insertion portion 21, and a second portion 22b that is located at a position different from the first portion 22a. In addition to the first portion 22a and the second portion 22b, the inner wall 221 may further include the above-mentioned third portion 22c and fourth portion 22d.

[0034] Fig. 3 is a block diagram showing an example of the configuration of the stimulation device 10 of Fig. 1. With reference to Fig. 3, an example of the configuration and functions of the stimulation device 10 according to the first embodiment will be mainly described.

[0035] The stimulation device 10 includes any device that applies a stimulus to the inside of the human body from a predetermined site on the surface of the human body. For example, the stimulation device 10 generates a weak vibration that does not exceed the threshold of the user's senses as a stimulus and transmits it to the user's sensory organs. At this time, the user is in a state where he / she does not perceive the stimulus transmitted to the sensory organs at all or hardly perceives it at all. The stimulation device 10 has a communication unit 11, a memory unit 12, a drive unit 13, a stimulation unit 14, a power supply unit 15, and a control unit 16.

[0036] The communication unit 11 includes a communication module that conforms to a communication standard based on any wireless communication or wired communication. The communication standard includes a wireless LAN (Local Area Network) standard, a short-range wireless communication standard, a mobile communication standard such as 4G (4th Generation) and 5G (5th Generation), and an Internet standard. The stimulation device 10 is connected to an information communication network or the like via the communication unit 11.

[0037] The storage unit 12 includes a semiconductor memory, a magnetic memory, an optical memory, or any combination thereof. The storage unit 12 functions as, for example, a main storage device, an auxiliary storage device, or a cache memory. The storage unit 12 stores data used in the operation of the stimulation device 10 and data obtained by the operation of the stimulation device 10. For example, the storage unit 12 stores system programs, application programs, and various data received or transmitted by the communication unit 11.

[0038] The driving unit 13 includes an arbitrary driving circuit for driving the stimulation unit 14. The driving circuit includes a transducer driving circuit for driving a transducer included in the stimulation unit 14, and the like.

[0039] The stimulating unit 14 includes any vibrator that generates weak vibrations. The vibrator includes a piezoelectric element and a linear vibration actuator. The vibrator may be configured by using at least one element of one type, or may be configured by using a plurality of elements of different types. When the wearing body 1 is worn on a part of the human body, the stimulating unit 14 applies a stimulus from a predetermined part on the surface of the human body to the inside of the human body. For example, the stimulating unit 14 generates a weak vibration that does not exceed the threshold of the user's senses as a stimulus based on the control by the control unit 16, and transmits the vibration to the sensory organ of the user. The stimulating unit 14 is located in the second part 22b described above in the housing 20 of the wearing body 1, and applies a stimulus to the user's finger.

[0040] The power supply unit 15 includes any power supply that supplies the power necessary to operate the stimulation device 10. The power supply includes a primary battery, a secondary battery, and the like.

[0041] The control unit 16 includes a processor, a programmable circuit, a dedicated circuit, or any combination thereof. The processor includes a general-purpose processor such as a central processing unit (CPU) or a graphics processing unit (GPU), or a dedicated processor specialized for a specific process. The programmable circuit includes a field-programmable gate array (FPGA), etc. The dedicated circuit includes an application specific integrated circuit (ASIC), etc. The control unit 16 is communicably connected to each component of the stimulation device 10, and executes processes related to the operation of the stimulation device 10 while controlling each component.

[0042] Fig. 4 is a schematic diagram showing an example of the arrangement of the stimulation unit 14 of the stimulation device 10 of Fig. 2. The configuration and function of the stimulation unit 14 of the stimulation device 10 according to the first embodiment will be described in more detail with reference to Fig. 4.

[0043] The stimulator 14 including the vibrator is disposed at a position where a ratio ΔD2 / D1 of a variation ΔD2 of a thickness D2 of the second tissue B2 to a distance D1 from a first tissue B1 included inside the human body to the stimulator 14 is equal to or less than a first threshold value. In the present disclosure, the "first tissue B1" includes a relatively hard tissue of the first tissue B1 and the second tissue B2. The first tissue B1 includes, for example, a tendon B11 or a bone B12. The "second tissue B2" includes a relatively soft tissue of the first tissue B1 and the second tissue B2, and is located between the first tissue B1 and the predetermined site P1. The second tissue B2 includes, for example, a muscle.

[0044] The distance D1 from the first tissue B1 to the stimulation unit 14 includes, for example, the distance from the surface of the skin B3 side of the tendon B11, which is closer to the skin B3 of the finger out of the tendon B11 and the bone B12, to the surface of the skin B3 side of the stimulation unit 14. The thickness D2 of the second tissue B2 includes, for example, the thickness of the second tissue B2 between the skin B3 and the tendon B11, which is closer to the skin B3 of the finger out of the tendon B11 and the bone B12.

[0045] The variation ΔD2 of the thickness D2 of the second tissue B2 includes, for example, a difference in the thickness D2 of the second tissue B2 that changes for each pressure applied to the predetermined site P1 depending on the wearing state of the wearing body 1 when the wearing body 1 is worn on a part of the human body so that the stimulation unit 14 is located at the predetermined site P1. The difference is, for example, a value when the thickness D2 of the second tissue B2 when no pressure is applied to the predetermined site P1 is used as a reference value.

[0046] The amount of variation ΔD2 when calculating the ratio ΔD2 / D1 is obtained, for example, by calculating the average or maximum value of the absolute values ​​of various differences from the reference value of the thickness D2. The ratio ΔD2 / D1 includes, for example, a value obtained by dividing the amount of variation ΔD2 by the distance D1 from the surface of the tendon B11 on the skin B3 side to the surface of the stimulation unit 14 on the skin B3 side when no pressure is applied to the specific site P1.

[0047] In the example of the first embodiment shown in Fig. 4, the predetermined site P1 is included on the surface of the finger of the hand. For example, the predetermined site P1 is included on the surface of the skin of the finger side S3 located between the finger dorsum S1 and the finger pad S2 of the finger. The predetermined site P1 is located at a side position of the finger side S3 that is shifted along the contour of the finger from the apex P2 on the back side of the hand in the cut surface of the finger in Fig. 4. The side position includes a position where the angle θ formed by the line connecting the center P0 of the finger and the apex P2 and the line connecting the center P0 and the side position, i.e., the predetermined site P1, is an acute angle on the cut surface of the finger.

[0048] The predetermined site P1 is located at a position where the thickness D2 of the second tissue B2 is equal to or greater than the second threshold. At this time, the stimulation unit 14 is arranged in contact with the predetermined site P1. At the predetermined site P1 where the stimulation unit 14 is arranged in contact, the tendon B11 is thin, and the thickness D2 of the second tissue B2 located between the tendon B11 and the predetermined site P1 is relatively large. At an obliquely inclined position such as the predetermined site P1, the vein B4 is also arranged inside the human body, and the thickness D2 of the second tissue B2 is relatively large. On the other hand, for example, at the apex P2, the tendon B11 is thick, and the thickness D2 of the second tissue B2 located between the tendon B11 and the apex P2 is relatively small. For example, the thickness D2 at the predetermined site P1 is sufficiently larger than the minimum value, with the thickness D2 at the apex P2 being the minimum value.

[0049] At this time, the ratio ΔD2 / D1 becomes equal to or smaller than the first threshold value at the predetermined site P1 because the distance D1 at the predetermined site P1 is sufficiently larger than that at the apex P2. For example, assume that the variation ΔD2 of the thickness D2 of the second tissue B2 is the same at the predetermined site P1 and the apex P2. At this time, the thickness D2 at the predetermined site P1 is relatively larger than that at the apex P2. Therefore, the distance D1 at the predetermined site P1 is also larger than that when the stimulation unit 14 is similarly disposed so as to contact the apex P2. As a result, the value of the denominator of the ratio ΔD2 / D1 becomes larger, and the value of the ratio ΔD2 / D1 becomes smaller.

[0050] The first threshold and the second threshold are determined, for example, so that when the vibration pattern of the weak vibration transmitted from the stimulation unit 14 to the sensory organ inside the human body varies depending on the wearing state of the wearing body 1, the variation of the vibration pattern falls within an allowable range where the reproducibility of the improvement of the sensory sensitivity is obtained. For example, an index indicating the variation of the vibration pattern is calculated using any statistical method. The first threshold is determined for the ratio ΔD2 / D1 so that the index is smaller than a reference value where the reproducibility of the improvement of the sensory sensitivity is obtained. The second threshold is determined for the thickness D2 so that the index is smaller than a reference value where the reproducibility of the improvement of the sensory sensitivity is obtained.

[0051] The stimulation device 10 transmits weak vibrations to the sensory organ using a vibrator of the stimulation unit 14 that is placed in contact with a predetermined part P1. The sensory organ is located at the tip of the nerve B5 that extends from the cut surface of FIG. 4 to the fingertip. In this way, the stimulation device 10 effectively improves the sensory sensitivity of the fingertip by using the stochastic resonance phenomenon.

[0052] Second embodiment 5 is a schematic diagram showing an example of the arrangement of the stimulation unit 14 of the stimulation device 10 according to the second embodiment of the present disclosure. The configuration and function of the stimulation unit 14 of the stimulation device 10 according to the second embodiment will be described with reference to FIG.

[0053] The stimulation device 10 according to the second embodiment differs from the first embodiment in that it further has an interposition portion 17 sandwiched between the stimulation portion 14 and the predetermined site P1. Other configurations, functions, effects, and modifications are the same as those of the first embodiment, and the corresponding explanations apply to the stimulation device 10 and the wearing body 1 according to the second embodiment. In the following, the same components as those in the first embodiment are given the same reference numerals, and the explanations thereof will be omitted. The points different from the first embodiment will be mainly explained.

[0054] In the second embodiment, the predetermined site P1 is located at a position where the thickness D2 of the second tissue B2 is less than the second threshold value. The predetermined site P1 is located at the apex P2 on the back side of the hand on the cut surface of the finger. The interposition unit 17 is disposed between the predetermined site P1 and the stimulation unit 14 so as to be in contact with both of them.

[0055] The interposition unit 17 is made of any material capable of transmitting the weak vibrations output from the stimulation unit 14 from the predetermined site P1 to the inside of the human body. The interposition unit 17 transmits the weak vibrations output from the stimulation unit 14 from the predetermined site P1 to the inside of the human body with a predetermined vibration intensity so that the vibrations can be finally transmitted to a sensory organ and the effect of the stochastic resonance phenomenon can be realized.

[0056] As described above, the tendon B11 is thick at the apex P2, and the thickness D2 of the second tissue B2 located between the tendon B11 and the apex P2 is relatively small. Therefore, the predetermined site P1 is located, for example, at a position where the thickness D2 of the second tissue B2 is less than the second threshold. However, unlike the case where the stimulation unit 14 is arranged so as to contact the apex P2, the stimulation unit 14 is arranged at the predetermined site P1 via the interposition unit 17, so that the distance D1 from the surface of the tendon B11 on the skin B3 side to the surface of the stimulation unit 14 on the skin B3 side becomes large.

[0057] At this time, the ratio ΔD2 / D1 becomes equal to or smaller than the first threshold value at the predetermined site P1 by making the distance D1 at the predetermined site P1 sufficiently large compared to when the interposition portion 17 is not used. For example, assume that the amount of variation ΔD2 in the thickness D2 of the second tissue B2 is the same when the interposition portion 17 is used at the apex P2 and when it is not used. At this time, the distance D1 is larger when the stimulation unit 14 is placed at the predetermined site P1 via the interposition portion 17. As a result, the value of the denominator of the ratio ΔD2 / D1 becomes larger, and the value of the ratio ΔD2 / D1 becomes smaller.

[0058] The stimulation device 10 transmits weak vibrations to the sensory organ using a vibrator of the stimulation unit 14 that is placed at a predetermined site P1 via an interposition unit 17. The sensory organ is located at the tip of a nerve B5 that extends from the cut surface of FIG. 5 to the fingertip. In this way, the stimulation device 10 effectively improves the sensory sensitivity of the fingertip by using the stochastic resonance phenomenon.

[0059] Third embodiment Fig. 6 is a schematic diagram showing an example of the arrangement of the stimulation unit 14 of the stimulation device 10 according to the third embodiment of the present disclosure. Fig. 6 is a schematic diagram showing a cut surface of the ankle as viewed from above. The configuration and function of the stimulation unit 14 of the stimulation device 10 according to the third embodiment will be described with reference to Fig. 6.

[0060] The stimulation device 10 according to the third embodiment differs from the first and second embodiments in that it is attached to a wearing body 1 that is worn on the ankle as part of the human body. Other configurations, functions, effects, and modifications are the same as those of the first and second embodiments, and the corresponding explanations apply to the stimulation device 10 and wearing body 1 according to the third embodiment. In the following, the same components as those of the first and second embodiments are given the same reference numerals, and the explanations thereof are omitted. The differences from the first and second embodiments will be mainly explained.

[0061] In the third embodiment, the part of the human body includes the ankle. For example, the wearing body 1 is worn on the ankle. The wearing body 1 has a ring-shaped housing 20 to which the stimulation device 10 is attached and which surrounds the ankle. The wearing body 1, when worn on the ankle via the housing 20, applies stimulation to the ankle using the stimulation device 10.

[0062] The housing 20 has an insertion section 21 formed by a space surrounding the ankle. The housing 20 has a frame section 22 surrounding the insertion section 21. The housing 20 has a hinge mechanism 23 formed on one side of the frame section 22. The housing 20 has a clasp 24 formed on the other side of the frame section 22.

[0063] The shape of the housing 20 configured like an ankle may be changed for each user according to the shape of the user's ankle so that the vibrator of the stimulation unit 14 adheres closely to the skin B3 of the ankle and efficiently transmits weak vibrations to the inside of the ankle. The clasp 24 of the housing 20 is disposed on the Achilles tendon B11 side of the ankle. The hinge mechanism 23 of the housing 20 is disposed in front of the ankle. The housing 20 has a shape that does not allow it to rotate around the ankle with the foot as the axis. The user opens the clasp 24 to wear the wearing body 1 on the ankle and to remove it from the ankle.

[0064] The housing 20 of the wearing body 1 has a ring shape. A pair of stimulating units 14 having vibrators are arranged on the sides of the ankle as shown in Fig. 6. For example, the stimulating units 14 having vibrators are attached to a frame 22 of the housing 20 having a ring shape. When the user wears the wearing body 1 like an ankle ring, the stimulating device 10 transmits weak vibrations from the vibrators of the stimulating unit 14 to the inside of the ankle via a predetermined part P1.

[0065] The pair of vibrators attached to the frame 22 are arranged at positions far away from the tibia B12 and Achilles tendon B11 included in the first tissue B1 so as to reduce the variation in the vibration pattern of the sensory organs for weak vibrations. As a result, the ratio of the amount of variation in the thickness of the relatively soft second tissue B2 located between the first tissue B1 and the predetermined site P1 to the distance from the relatively hard first tissue B1 to the stimulation unit 14 becomes equal to or less than the first threshold value, as in the first and second embodiments.

[0066] The tibia B12 and Achilles tendon B11 are arranged in part close to the skin B3 of the ankle. Therefore, when the stimulation unit 14 is arranged in close proximity to the part of the tibia B12 and Achilles tendon B11, the vibration pattern of the weak vibration transmitted to the sensory organ varies depending on the wearing state of the wearing body 1. In contrast, the stimulation unit 14 is arranged in a position different from such a position. Therefore, the variation of the weak vibration transmitted to the sensory organ such as the toe is reduced. As a result, the reproducibility of the improvement in sensory sensitivity due to the stochastic resonance phenomenon is improved.

[0067] (effect) According to the stimulation device 10 and the wearing body 1 according to one embodiment including each of the first to third embodiments as described above, it is possible to improve the reproducibility of the improvement of the sensory sensitivity. In the stimulation device 10, the stimulation unit 14 is disposed at a position where the ratio ΔD2 / D1 of the amount of variation ΔD2 of the thickness D2 of the second tissue B2 to the distance D1 from the first tissue B1 to the stimulation unit 14 is equal to or less than a first threshold value. This makes it possible for the stimulation device 10 to reduce the variation in the vibration pattern of the weak vibration transmitted from the stimulation unit 14 to the sensory organ in the sensory organ. Therefore, the reproducibility of the weak vibration that causes the stochastic resonance phenomenon is improved in the sensory organ. As a result, the reproducibility of the effect of improving the sensory sensitivity obtained by the stochastic resonance phenomenon is also improved.

[0068] For example, referring to the cut surface of a finger shown in Fig. 4, the first tissue B1, such as the bone B12 and the tendon B11 connecting the bone B12 to the second tissue B2, such as the muscle, is located near the finger back S1 on the cut surface of the finger. When the finger is bent toward the palm, the first tissue B1 approaches the finger back S1. In the part inside the finger located on the finger back S1 side, the thickness D2 of the second tissue B2 is very thin.

[0069] The first tissue B1, such as the tendon B11 and the bone B12, is made of a relatively hard material even inside the human body, and is easy to transmit vibration. Therefore, when the vibrator of the stimulation unit 14 is placed at the apex P2, for example, it is expected that the ease of vibration transmission will change sensitively depending on the positional relationship between the first tissue B1 and the vibrator. As a result, when the stimulation unit 14 is placed at the apex P2, for example, and close to the first tissue B1, the vibration pattern of the weak vibration transmitted to the sensory organ tends to vary depending on the wearing state of the wearing body 1.

[0070] In contrast, when the stimulation unit 14 is placed in contact with the skin B3, if it is placed at a predetermined site P1 at a slightly inclined position avoiding the apex P2, the thickness D2 of the second tissue B2 becomes slightly larger due to the vein B4, etc. This reduces the ratio ΔD2 / D1. As a result, the stimulation device 10 reduces the variation in the vibration pattern in the sensory organ depending on the wearing state of the wearing body 1, and makes it possible to increase the reproducibility of the improvement in sensory sensitivity due to the stochastic resonance phenomenon.

[0071] In the first and second embodiments, the predetermined site P1 is included on the surface of the finger, and the stimulation device 10 can transmit weak vibrations from the predetermined site P1 to the sensory organs of the fingertip by using the vibrator of the stimulation unit 14. This allows the stimulation device 10 to effectively improve the sensory sensitivity of the fingertip by using the stochastic resonance phenomenon.

[0072] In the third embodiment, the predetermined site P1 is included on the surface of the ankle, and thus the stimulation device 10 can transmit weak vibrations from the predetermined site P1 to the sensory organs of the foot using the vibrator of the stimulation unit 14. This allows the stimulation device 10 to effectively improve the sensory sensitivity of the foot by using the stochastic resonance phenomenon. By transmitting weak vibrations to the sensory organs of the foot, the stimulation device 10 can, for example, stabilize the movement of the center of gravity of a user wearing the wearing body 1 on the ankle and reduce shaking during walking.

[0073] In the first embodiment, the stimulation unit 14 is arranged in contact with the predetermined site P1, and thus the stimulation device 10 can achieve the above-mentioned effect regarding the stochastic resonance phenomenon with a simple configuration using only the stimulation unit 14 at the predetermined site P1 where the thickness D2 of the second tissue B2 is equal to or greater than the second threshold. The stimulation device 10 can be simply configured without requiring an additional configuration such as the interposition unit 17.

[0074] In the first embodiment, the predetermined site P1 is located on a side of the cut surface of the finger, shifted from the vertex P2 on the back of the hand along the contour of the finger. This allows the stimulation device 10 to directly place the stimulation unit 14 at a position where the thickness D2 of the second tissue B2, which is located between the tendon B11 (the first tissue B1) and the skin B3, is large.

[0075] In the first embodiment, the side position includes a position on the cut surface of the finger where the angle θ between the line connecting the center P0 and the vertex P2 of the finger and the line connecting the center P0 and the side position is an acute angle. This allows the stimulation device 10 to directly place the stimulation unit 14 at a position where the thickness D2 of the second tissue B2 located between the tendon B11, which is the first tissue B1, and the skin B3 is large.

[0076] In the second embodiment, the stimulation device 10 further includes an intervening portion 17 sandwiched between the stimulation unit 14 and the predetermined site P1. As a result, even in the predetermined site P1 where the thickness D2 of the second tissue B2 is less than the second threshold, the stimulation device 10 can increase the distance D1 by the intervening portion 17, thereby realizing the above-mentioned effect regarding the stochastic resonance phenomenon.

[0077] In the second embodiment, the predetermined site P1 is at the vertex P2 on the back side of the hand on the cut surface of the finger. This allows the stimulation device 10 to place the stimulation unit 14 at the most convenient position on the outer circumference of the hand. The stimulation device 10 can achieve the above-mentioned effect regarding the stochastic resonance phenomenon, for example, even at the vertex P2 where the thickness D2 of the second tissue B2 is small, by increasing the distance D1 using the interposition unit 17.

[0078] In the first and second embodiments, the wearing body 1 is configured as a ring-shaped device, so that the user can easily wear the wearing body 1 by simply putting it on the finger. Therefore, the convenience of the wearing body 1 is improved.

[0079] In the third embodiment, the wearing body 1 is configured as an ankle-shaped device, so that the user can easily wear the wearing body 1 by simply putting it on the foot. Therefore, the convenience of the wearing body 1 is improved.

[0080] Fig. 7 is a first diagram for explaining the effect of the present disclosure. Fig. 8 is a second diagram for explaining the effect of the present disclosure. Fig. 9 is a third diagram for explaining the effect of the present disclosure. Fig. 10 is a fourth diagram for explaining the effect of the present disclosure. The above-mentioned effect of the present disclosure will be described in more detail with reference to Figs. 7 to 10.

[0081] As an example, in order to improve sensory sensitivity at the fingertips by using the stochastic resonance phenomenon, the applicant attached a vibrator V0 to the finger of a subject and measured the frequency of the vibration transmitted to the subject's fingertip. As shown in Figure 7, the vibrator V0 was placed on the back S1 of the subject's index finger, and a first acceleration sensor V1 was placed between the vibrator V0 and the back S1. A second acceleration sensor V2 was also placed on the finger pad S2 of the fingertip where the stochastic resonance phenomenon was desired to be excited.

[0082] As shown in Fig. 8, the vibration from the oscillator V0 is a weak vibration that excites the stochastic resonance phenomenon. The weak vibration is basically represented by a sine wave, but the frequency f increases stepwise from 10 Hz to 500 Hz over a period of 30 seconds. Based on the arrangement shown in Fig. 7, the amplitude of the weak vibration in the first acceleration sensor V1 is expressed as A in The amplitude of the weak vibration in the second acceleration sensor V2 is represented as A out In this case, the frequency characteristic G(f) from the vibrator V0 to the fingertip is expressed by Equation 1.

[0083]

number

[0084] FIG. 9 shows the measured frequency characteristic G(f). FIG. 9 shows the frequency characteristic G(f) when the vibrator V0 was placed at a position corresponding to the apex P2 of the subject's index finger. The measurement of the frequency characteristic G(f) was performed three times, from try 1 to try 3. As shown in FIG. 9, even though the vibrator V0 was placed at the same position all three times, the frequency characteristic G(f) varies, and the vibration pattern of the weak vibration varies. As described above, when the vibrator V0 was placed at a position corresponding to the apex P2 of the subject's index finger, stable results were not obtained.

[0085] FIG. 10 shows the measured frequency characteristic G(f). FIG. 10 shows the frequency characteristic G(f) when the vibrator V0 is placed at a position corresponding to the specific part P1 shown in FIG. 4 on the subject's index finger. The measurement of the frequency characteristic G(f) is performed three times, from try 1 to try 3. Compared with the result of FIG. 9, when the vibrator V0 is placed at the same position three times, the variation of the frequency characteristic G(f) is reduced, and the variation of the vibration pattern of the weak vibration is reduced. Compared with the case where the vibrator V0 is placed at a position corresponding to the apex P2, a more stable frequency characteristic G(f) is obtained.

[0086] As described above, the stimulation device 10 and the wearing body 1 can transmit weak vibrations from the vibrator of the stimulation unit 14 to the sensory organ with good reproducibility by arranging the stimulation unit 14 at a position where the ratio ΔD2 / D1 is equal to or less than the first threshold. In other words, the variation in the vibration pattern of the weak vibration transmitted to the sensory organ is reduced every time the wearing body 1 is worn as a ring-shaped or ankle-shaped device. As a result, the stimulation device 10 and the wearing body 1 can realize the improvement of sensory sensitivity obtained by the stochastic resonance phenomenon with good reproducibility.

[0087] It is obvious to those skilled in the art that the present disclosure can be realized in other specific forms other than the above-described embodiments without departing from the spirit or essential characteristics thereof. Therefore, the above description is illustrative and not limiting. The scope of the disclosure is defined by the appended claims, not by the above description. Any modifications within the scope of the equivalents of all modifications are intended to be included therein.

[0088] For example, the shape, pattern, size, arrangement, orientation, type, and number of each of the above-mentioned components are not limited to the above description and the contents illustrated in the drawings. The shape, pattern, size, arrangement, orientation, type, and number of each of the components may be configured arbitrarily as long as the function can be realized. The components of the stimulation device 10 and the wearing body 1 illustrated in the drawings are functional concepts, and the specific form of each component is not limited to those illustrated.

[0089] For example, functions included in each configuration can be rearranged so as not to cause logical inconsistencies, and multiple configurations can be combined into one or divided. Other modifications are possible within the scope of the present disclosure.

[0090] In the embodiment including each of the first to third embodiments, the stimulation unit 14 is disposed at a position where the ratio ΔD2 / D1 becomes equal to or less than the first threshold value as the distance D1 increases, but the present invention is not limited to this. The stimulation unit 14 may be disposed at a position where the ratio ΔD2 / D1 becomes equal to or less than the first threshold value as the variation amount ΔD2 is small even if the distance D1 is small.

[0091] In the above-described first to third embodiments, the predetermined site P1 is described as being included in the surface of a finger or the surface of an ankle, but is not limited thereto. The predetermined site P1 may be included in any other part of the human body.

[0092] In the first embodiment, the side position includes a position where the angle θ between the line connecting the center P0 and the vertex P2 of the finger and the line connecting the center P0 and the side position is an acute angle on the cut surface of the finger, but is not limited to this. The side position may include a position where the angle θ is 90° or an obtuse angle.

[0093] In one embodiment including each of the above first to third embodiments, the wearing body 1 has been described as including all the components of the stimulation device 10 in the housing 20 and functioning as one device, but is not limited thereto. The wearing body 1 may be electrically connected to another control device such as a smart watch, for example, by wire or wirelessly. For example, the process executed by the control unit 16 of the stimulation device 10 of the wearing body 1 may be executed by the other control device while the other control device is communicatively connected to the wearing body 1.

[0094] In the above first and second embodiments, the attachment 1 is described as being located between the first joint located at the most distal end of the index finger of the hand and the second joint located next to the first joint on the back side of the hand from the first joint, but is not limited thereto. The attachment 1 may be located further on the back side of the hand from the second joint.

[0095] In the above first and second embodiments, the first portion 22a of the housing 20 is described as being formed flat, but is not limited thereto. The first portion 22a does not have to be formed flat. The first portion 22a may have any structure that can be arranged to match the back of the user's finger.

[0096] Some of the embodiments of the present disclosure will be described below as examples. However, it should be noted that the embodiments of the present disclosure are not limited to these examples. [Appendix 1] A stimulation unit that applies a stimulation to an inside of the human body from a predetermined site on a surface of the human body, The stimulation unit is disposed at a position where a ratio of a variation in thickness of the second tissue, which is relatively soft and located between the first tissue and the predetermined site, to a distance from the first tissue, which is relatively hard among the first tissue and the second tissue contained inside the human body, to the stimulation unit is equal to or less than a first threshold value. Stimulator. [Appendix 2] 2. The stimulation device of claim 1, The predetermined site is included in the surface of a finger of a hand. Stimulator. [Appendix 3] 3. The stimulation device of claim 2, The stimulation unit is arranged in contact with the predetermined site, The predetermined site is located at a position where the thickness of the second tissue is equal to or greater than a second threshold value. Stimulator. [Appendix 4] 4. The stimulation device of claim 3, The predetermined portion is located at a side position shifted along the contour of the finger from the vertex on the back side of the hand on the cut surface of the finger. Stimulator. [Appendix 5] 5. The stimulation device of claim 4, The side position includes a position on the cut surface where an angle formed by a line connecting the center of the finger and the vertex and a line connecting the center and the side position is an acute angle. Stimulator. [Appendix 6] 6. The stimulation device according to claim 2, further comprising: Further, an interposition portion is provided between the stimulation portion and the predetermined portion, The predetermined site is located at a position where the thickness of the second tissue is less than a second threshold value. Stimulator. [Appendix 7] 7. The stimulation device of claim 6, The predetermined portion is located at the apex of the back of the hand on the cut surface of the finger. Stimulator. [Appendix 8] 8. The stimulation device according to claim 2, further comprising: the first tissue comprises a tendon or a bone; The second tissue comprises a muscle. Stimulator. [Appendix 9] A stimulation unit is provided on the surface of a finger of a hand, which provides stimulation to the inside of the human body from a side position shifted along the contour of the finger from the apex on the back side of the hand on the cut surface of the finger. Stimulator. [Appendix 10] A step of applying a stimulus to the inside of a human body from a lateral position shifted along a contour of a finger from a vertex on the back side of the hand on a surface of the finger of a hand on a cut surface of the finger, Stimulation method. [Appendix 11] A ring-shaped housing that surrounds an area into which a user's finger can be inserted, The housing includes: an inner wall including a first portion that contacts or is close to a vertex of the cut surface of the finger on the back side of the hand when the finger is inserted into the region, and a second portion that is located at a position different from the first portion; A stimulation unit located in the second portion and configured to provide a stimulation to the finger. Wearable body. [Explanation of symbols]

[0097] 1. Wearing body 10 Stimulator 11 Communications Department 12 Storage section 13 Drive unit 14 Stimulation part 15 Power supply section 16 Control section 17 Interposition 20. Cabinet 21 Insertion section 22 Frame 221 Interior wall 22a Part 1 22b Part 2 22c Part 3 22d 4th part 23 Hinge mechanism 24 Clasp B1 1st organization B11 Tendon B12 Bone B2 2nd organization B3 skin B4 Vein B5 Nerve D1 Distance D2 Thickness ΔD fluctuation amount L1 slope line L2 slope line P0 center P1 Specified part P2 Vertex S1 finger dorsum S2 finger pad S3 Finger side V0 transducer V1 First acceleration sensor V2 Second acceleration sensor

Claims

1. A stimulation unit that applies a stimulation to an inside of the human body from a predetermined site on a surface of the human body, The stimulation unit is disposed at a position where a ratio of a variation in thickness of the second tissue, which is relatively soft and located between the first tissue and the predetermined site, to a distance from the first tissue, which is relatively hard among the first tissue and the second tissue contained inside the human body, to the stimulation unit is equal to or less than a first threshold value. Stimulator.

2. 2. The stimulation device of claim 1, The predetermined site is included in the surface of a finger of a hand. Stimulator.

3. 3. The stimulation device of claim 2, The stimulation unit is arranged in contact with the predetermined site, The predetermined site is located at a position where the thickness of the second tissue is equal to or greater than a second threshold value. Stimulator.

4. 4. The stimulation device of claim 3, The predetermined portion is located at a side position shifted along the contour of the finger from the vertex on the back side of the hand on the cut surface of the finger. Stimulator.

5. 5. The stimulation device of claim 4, The side position includes a position on the cut surface where an angle formed by a line connecting the center of the finger and the vertex and a line connecting the center and the side position is an acute angle. Stimulator.

6. 6. A stimulation device according to any one of claims 2 to 5, Further, an interposition portion is provided between the stimulation portion and the predetermined portion, The predetermined site is located at a position where the thickness of the second tissue is less than a second threshold value. Stimulator.

7. 7. The stimulation device of claim 6, The predetermined portion is located at the apex of the back of the hand on the cut surface of the finger. Stimulator.

8. 6. A stimulation device according to any one of claims 2 to 5, the first tissue comprises a tendon or a bone; The second tissue includes a muscle. Stimulator.

9. A stimulation unit is provided on the surface of a finger of a hand, which provides stimulation to the inside of the human body from a side position shifted along the contour of the finger from the apex on the back side of the hand on the cut surface of the finger. Stimulator.

10. A step of applying a stimulus to the inside of a human body from a lateral position shifted along a contour of a finger from a vertex on the back side of the hand on a surface of the finger of a hand on a cut surface of the finger, Stimulation method.

11. A ring-shaped housing that surrounds an area into which a user's finger can be inserted, The housing includes: an inner wall including a first portion that contacts or is close to a vertex of the cut surface of the finger on the back side of the hand when the finger is inserted into the region, and a second portion that is located at a position different from the first portion; A stimulation unit located in the second portion and configured to provide a stimulation to the finger. Wearable body.

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