JP2014228507A - Extension sensor and measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an extension sensor that suppresses restriction, discomfort, burden, and dermatitis to a subject, and allows a long period wearing for use.SOLUTION: An extension sensor includes a resistor 1 comprising an elastically deformable substrate in which a mixture containing electro-conductive polymer and binder resin is fixed on at least part of its surface and inside, and a pair of terminals 2a and 2b electrically connected with the edge of the conductive surface of the resistor 1. The substrate is made of fiber or cloth.

Description

  The present invention relates to a fiber or cloth-like extension sensor in which a resistance change is caused by elastic deformation, and a measuring device using the extension sensor. More specifically, the present invention relates to an extension sensor using a composite material of a conductive polymer and a base material capable of elastic deformation.

  Conventionally, motion capture systems have been put to practical use mainly as a method for acquiring motion data such as joint motions, and are used as input to virtual reality systems and game consoles, support for the elderly's independence motion, rehabilitation, or sports motion learning. (Non-Patent Document 1).

  In addition to these examples, sensors can be installed directly on the human body and peripheral devices, or sensors can be installed around it to acquire biological information from the human body and information from peripheral devices. Technological development in the field of environmental intelligence motion and wearable computing utilizing the acquired information is being actively promoted (Patent Document 1, Non-Patent Document 2).

  In order to realize such a motion capture, a mounting tool called a data glove or a data suit for inputting operation data to various information processing apparatuses has been proposed (Patent Document 2).

JP 2005-250708 A JP 2000-329511 A

Hooman Dejnabadi, Brigitte M. Joles, Emilio Casanova, Pascal Fua, and Kamiar Aminian, “Estimation and Visualization of Sagittal Kinematics of Lower Limbs Orientation Using Body-Fixed Sensors”, IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, VOL.53, NO.7, JULY 2006 Shigeki Yokoi, “Trends and Prospects of Medical Application of Virtual Reality”, Medical Imaging Technology, Vol.12, No.5, p.606-611, 1994

In order to detect motion information by sensing as described above, measurement without restraint that does not interfere with the subject's natural movement or daily life and measurement without discomfort or burden on the subject's body are desired. That is, a high quality interface including not only the physical characteristics of the sensor but also a feeling of wearing is required. For example, it is expected to realize a sensor that does not feel uncomfortable even if the sensor is worn over a long period of time, such as underwear, gloves, socks, knee pads, elbow pads, etc. Has been.
However, the sensor disclosed in Patent Document 2 is an electrode formed on a sheet-like member made of an electrically insulating material, lacks flexibility and air permeability, and can withstand long-term mounting. It wasn't.

  In view of such a problem, an object of the present invention is to provide an extension sensor that can suppress long-term wearing by suppressing restraint, discomfort, burden, and skin inflammation on a subject.

The elongation sensor of the present invention comprises a resistor comprising a base material capable of elastic deformation, a mixture containing a conductive polymer and a binder resin fixed to at least a part of the surface and the inside of the base material, And a pair of terminals electrically connected to the end of the conductive surface of the resistor.
Moreover, in one structural example of the extension | expansion sensor of this invention, the said base material is a fiber or a cloth.
Moreover, in one configuration example of the extension sensor of the present invention, the resistor may be formed in a cylindrical shape.
Moreover, in one structural example of the extension sensor of the present invention, the resistor may be incorporated into clothing.
Further, in one configuration example of the extension sensor of the present invention, the base material constituting the resistor includes a stopper structure for suppressing reaching the plastic deformation region when tension is applied from the outside. is there.
Further, the measuring device of the present invention includes an extension sensor, a table that stores in advance a relationship between a change in length or angle of a measurement object to which the extension sensor is attached, and a resistance value of the resistor, It is characterized by comprising information acquisition means for referring to the table based on the resistance value of the resistor and acquiring information on a change in length or an angle change corresponding to the resistance value.

  In the present invention, a resistor comprising a base material that is elastically deformable, a mixture containing a conductive polymer and a binder resin fixed to at least a part of the surface and inside of the base material, and a conductive surface of the resistor An extension sensor is composed of a pair of terminals electrically connected to the ends of the sensor. In the present invention, since the conductive polymer is kneaded in a solidified (cured) binder resin (polymer), and fixed to a base material capable of elastic deformation, the resistor is used. Structural breakdown is unlikely to occur, and high conductivity can be maintained over a long period of time. Moreover, a flexible resistor can be formed by taking advantage of the inherent flexibility of the substrate. Despite the state in which the conductive polymer is kneaded into the binder resin, the conductivity of the conductive polymer is so high that it can be used practically without any problem, and hardly deteriorates. For this reason, since the conductive polymer contained in the solidified binder resin can transmit a weak change in electric signal due to a resistance change, high-sensitivity and high-accuracy signal transmission / reception is performed between the extension sensor and the external device. be able to. Furthermore, since the mechanical strength of the resistor is enhanced by the solidified binder resin, it is possible to reduce the possibility that the resistor will be damaged by an external force when the extension sensor is attached to the human body. An excellent extension sensor can be realized. In addition, in the present invention, particularly high wearability required for a wearable device that is used in contact with the skin for a long period of time, that is, when touching, each requirement of touch feeling, thinness, flexibility, strength, and breathability is intricately involved. Comfort can be realized. As described above, in the present invention, restraint on the subject, discomfort, burden, and skin inflammation are suppressed, and long-term wearing becomes possible.

  Further, in the present invention, by forming the resistor in a cylindrical shape that can be attached to the measurement location of the measurement object, the extension sensor can be installed so as to follow the deformation of the measurement location. An extension sensor that detects deformation can be realized. According to the present invention, it is possible to detect a deformation of a measurement object having a complicated shape, and it is possible to provide a sensor having a simple structure and inexpensive. In the present invention, the extension sensor can be easily formed into an arbitrary shape by a known manufacturing technique.

  In the present invention, by incorporating the resistor into the clothing, the extension sensor can be installed so as to follow the deformation of the subject's joint and the like, and an extension sensor that detects the movement of the subject can be realized.

  Further, in the present invention, by providing the base material with a stopper structure for preventing the plastic deformation region from being reached when tension is applied from the outside, it is possible to avoid the hysteresis characteristic of the resistance change that occurs during tension. it can.

It is a top view which shows the structure of the expansion | extension sensor which concerns on the 1st Embodiment of this invention. It is a figure which shows the measuring method of the change of the resistance value of the expansion | extension sensor which concerns on the 1st Embodiment of this invention. It is the photograph which image | photographed the resistor of the expansion | extension sensor which concerns on the 1st Embodiment of this invention from upper direction. It is a figure which shows the measurement result of the change of the resistance value of the expansion | extension sensor which concerns on the 1st Embodiment of this invention. It is a top view which shows the structure of the expansion | extension sensor which concerns on the 2nd Embodiment of this invention. It is a figure which shows the state which wound the expansion | extension sensor around the elbow of the human body in the 3rd Embodiment of this invention. It is a perspective view which shows the resistor of the expansion | extension sensor which concerns on the 3rd Embodiment of this invention.

  The inventors of the present invention show that a fiber (thread) made of a conductive polymer typified by PEDOT-PSS has high hydrophilicity and flexibility, while the fiber is structurally in contact with sweating skin or the like. The present invention was completed as a result of repeated studies on the problem of disintegration of the fiber and the extensibility of the fiber. In the present invention, a resistor is obtained by using, as a resistor, a material that is kneaded in a binder resin (polymer) solidified (cured) and fixed to a base material that can be elastically deformed. Therefore, it is difficult to cause structural collapse, and high conductivity can be maintained over a long period of time.

[First Embodiment]
Hereinafter, the present invention will be described based on preferred embodiments with reference to the drawings. However, the present invention is not limited to such embodiments.
In the present embodiment, a base material capable of elastic deformation in which a mixture containing a conductive polymer and a binder resin is fixed to at least a part of the surface and the inside is used as a resistor of the extension sensor. As a base material capable of elastic deformation, there is a fiber or a cloth.

  The kind in particular of conductive polymer is not restrict | limited, A conventionally well-known conductive polymer is applicable. For example, PEDOT-PSS, PEDOT-S etc. which are excellent in electroconductivity and hydrophilicity are mentioned. By using a conductive polymer having excellent hydrophilicity, the hydrophilicity of the conductive portion of the conductor of this embodiment can be increased. A conductor having a highly hydrophilic conductive site has a high affinity for the skin, and thus is suitable for the use of an extension sensor described later.

  PEDOT-PSS is a conductive polymer obtained by polymerizing 3,4-ethylenedioxythiophene, which is a monomer, in the presence of poly (4-styrenesulfonic acid). PSS functions as a dopant that imparts a negative charge to PEDOT. From the viewpoint of increasing the conductivity of the conductive polymer, the conductive polymer preferably contains a dopant.

  The conductor in which PEDOT-PSS is solidified alone gels in a relatively wet environment such as sweating skin due to the high water absorption of PEDOT-PSS, and the mechanical strength is extremely reduced. For this reason, it is difficult to install a conductor made of PEDOT-PSS processed into a rod shape or a plate shape on the skin surface and use it for a long time.

  The resistor according to the present embodiment includes a resin composition in which at least one of a binder resin as an adhesive material and a monomer of the binder resin and a conductive polymer as a conductive filler are mixed, or a solvent as necessary. A conductor obtained by adhering a resin composition to which a resin is added to a substrate capable of elastic deformation by coating, printing, dipping, spraying, dropping, etc., and further solidifying or polymerizing by drying, heating, heating, etc. It is. In this conductor, the conductive polymer contained in the solidified resin composition (mixture) is kneaded into the binder resin, solidified, and further supported by the base material, which is excellent in durability.

The type of the binder resin is not particularly limited, and any conventionally known binder resin can be used as long as it is capable of adhering (binding) the conductive polymer to the base material without deactivating the conductivity of the conductive polymer. The binder resin is applicable.
One kind of binder resin may be used alone, or two or more kinds may be used in combination. By combining two or more binder resins, the curability, adhesiveness (tackiness), and ease of handling (workability such as coating) of the binder resin may be improved.

  As the binder resin, for example, a thermoplastic resin, a thermosetting resin, a photocurable resin, or the like is used. For example, Nafion, polycarbonate, polyacrylonitrile, polyethylene, polypropylene, polybutene, polyether, polyester, polystyrene, poly-p- Thermoplastic resins including thermoplastic elastomers such as xylene, polyvinyl acetate, polyacrylate, polymethacrylate, polyvinyl chloride, polyvinylidene chloride, polyvinyl ether, polyvinyl ketone, polyamide, butadiene resin, fluorine resin, polyurethane resin, Thermal curing of urea resin, melamine resin, modified silicone resin, phthalic acid resin, phenol resin, furan resin, aniline resin, unsaturated polyester resin, xylene / formaldehyde resin, epoxy resin, etc. Resin, epoxy acrylate, acrylic epoxy cationic polymerization, and the like photocurable resin such as photosensitive polyimide. Of these, the various vinyl resins, Nafion, polyamide, polyethylene, polypropylene, phthalic acid resin, modified silicone resin, and acrylic resin are preferable.

  In particular, an acrylic resin is most preferable as a binder resin because it has high adhesiveness to a base material (fiber or cloth) and hardly peels off from the base material. Furthermore, the acrylic resin is easy to adjust the tackiness, has high processability, and imparts flexibility with additives, and is relatively easy to bond and cure. It is particularly suitable for applications that bind between fibers.

  On the other hand, polyvinyl alcohol (hereinafter PVA) is not necessarily a good material as a binder resin. PVA is not suitable because it has lower adhesive force than acrylic resins and is easily peeled off. Also, when PVA acetalization or curing treatment with a crosslinking agent is added for the purpose of reducing peeling, the strength of PVA as a polymer is improved, but the substrate (cloth) to which PVA is attached becomes hard and flexible. And touch feel worse. For this reason, it is not suitable to use PVA as a binder resin as a bioelectrode material that requires flexibility in direct contact with the skin.

  When an unpolymerized monomer that is a precursor of a binder resin is contained in the resin composition when the resistor according to the present embodiment is manufactured, the unpolymerized monomer remains in the mixture after polymerization (after solidification). You may do it. The monomer in the resin composition may be positively polymerized by heating (thermosetting), light irradiation (photocuring), addition of a polymerization accelerator, or the like after adhering to the substrate, or drying, It may be polymerized gently and spontaneously by heating, contact with air, or the like.

  When manufacturing the resistor according to the present embodiment, a resin (polymer) polymerized in advance may be contained in the resin composition as a binder resin. Preferable specific examples of such a binder resin include a polymer obtained by polymerizing the monomers exemplified below. Examples of the acrylic monomer include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, isobutyl (meth) acrylate, hexyl (meth) ) Acrylate, octyl (meth) acrylate, cyclohexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl (meth) acrylate, lauryl (meth) acrylate, methoxypolyethylene glycol # 400 (meth) acrylate, methoxypolyethylene glycol 1000 (meth) acrylate, methoxypolyethylene glycol # 2000 (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylamide, methyl (meth) acrylamide, ethyl (meth) acrylamide, propyl (meth) acrylamide, isopropyl (meth) acrylamide , Butyl (meth) acrylamide, diacetone (meth) acrylamide, N-methylol (meth) acrylamide, N-hydroxyethyl (meth) acrylamide, N-hydroxypropyl (meth) acrylamide, N-hydroxybutyl (meth) acrylamide, N- Methoxymethyl (meth) acrylamide, N-ethoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N-isobutoxymethyl (me ) Acrylamide, and the like.

  By using these acrylic resins as binder resins, it is possible to reliably fix a mixture of a conductive polymer and a binder resin to a base material, and wear resistance, peel resistance, water resistance, chemical resistance of the mixture. And the electrical conductivity of the conductive polymer embedded in the acrylic resin can be easily maintained.

  Furthermore, depending on the blending ratio of the conductive polymer and the acrylic resin in the mixture, the hydrophilicity and flexibility of the conductive polymer embedded in the acrylic resin is maintained, and these properties are added to the mixture. Is reflected to some extent. Hydrophilicity and flexibility are properties required as preferable characteristics of the bioelectrode described later. The reason why the properties of the conductive polymer are maintained even after being embedded in the acrylic resin is that the conductive polymers are kept in contact with each other even in the embedded state, and further, the surface of the mixture is highly conductive. This is probably because at least a part of the molecule is exposed.

  The content of the conductive polymer in the mixture is not particularly limited as long as the mixture maintains conductivity, but for example, 0.1 to 50% by weight is preferable, and 1 to 40% by weight is more preferable. 10 to 30% by weight is more preferable. When the content of the conductive polymer is not less than the lower limit of the above range (0.1 to 50% by weight), the conductivity of the mixture is further improved. When the content of the conductive polymer is not more than the upper limit of the above range (0.1 to 50% by weight), the balance of the content of the conductive polymer with respect to the binder resin is further improved, and the durability of the mixture is further improved. improves.

  The content of the binder resin in the mixture is not particularly limited as long as the mixture maintains conductivity. For example, the content is preferably 50 to 99.9% by weight, more preferably 60 to 99% by weight, and 70 More preferred is -90% by weight. When the content of the binder resin is not less than the lower limit of the above range (50 to 99.9% by weight), the balance of the binder resin content with respect to the conductive polymer becomes better, and the durability of the mixture is further improved. When the content of the binder resin is not more than the upper limit of the above range (50 to 99.9% by weight), the conductivity of the mixture is further improved.

  The total content of the conductive polymer and the binder resin in the mixture is not particularly limited as long as the mixture maintains conductivity, but is preferably 50 to 100% by weight, for example, 60 to 100% by weight. Is more preferable, and 80 to 100% by weight is still more preferable. When the total content of the conductive polymer and the binder resin is in the above range (50 to 100% by weight), the balance between the content of the conductive polymer and the binder resin becomes better, and the durability and conductivity of the mixture are improved. Is further improved.

  The weight ratio of the conductive polymer and the binder resin in the mixture is not particularly limited as long as the mixture maintains conductivity, but for example, the weight of the binder resin / the weight of the conductive polymer = 1-100. Are preferable, 2-10 are more preferable, 4-10 are still more preferable, and 4-6 are especially preferable. When the weight ratio of the conductive polymer and the binder resin is in the above range (4 to 10), the balance of the content of the conductive polymer and the binder resin becomes better, and the durability and conductivity of the mixture are further improved. .

  The base material used for the resistor of the present embodiment is not particularly limited as long as it can function as a base material for supporting the mixture, and conventionally used cloths for clothes and the like can be applied. The fabric is not limited to a woven fabric and may be a non-woven fabric.

  When a base material is a fiber, what fixed the said mixture to this base material becomes a conductive fiber. Moreover, when a base material is a fabric, what fixed the said mixture to this base material turns into a conductive cloth. The conductive fiber may be used as an electrical wiring or a one-dimensional (string-like) biological electrode, or may be used as a conductive cloth by weaving conductive fibers. The conductive cloth can be used as a two-dimensional stretch sensor.

  The state in which the mixture containing the conductive polymer and the binder resin is fixed to the substrate is a state in which at least a part of the substrate is covered with the mixture, or the mixture is in at least one region of the substrate. The state of adhering. The mixture fixed to the base material may be attached to both surfaces of the base material, or either the front surface or the back surface of the base material, and the fibers (threads) constituting the base material are fibers. You may adhere so that it may bind. When the mixture is adhered to both surfaces of the substrate, the conductive surface made of the mixture on the front surface and the conductive surface made of the mixture on the back surface may be electrically independent or electrically conductive. Also good. A part of the mixture may penetrate into the base material.

  Hereinafter, the extension sensor of the present embodiment will be described. As shown in FIG. 1, the extension sensor of the present embodiment includes a resistor 1 and a pair of terminals 2 a and 2 b electrically connected to both ends of the conductive surface of the resistor 1. It suffices that at least a part of the terminals 2 a and 2 b is electrically connected to the conductive surface of the resistor 1. As a method for fixing the terminals 2a and 2b to the conductive surface, for example, a method such as adhesion can be employed.

  The size of the conductive surface of the resistor 1 is not particularly limited, and is appropriately adjusted according to the application. In the example of FIG. 1, the resistor 1 has a conductive surface on the entire front surface and back surface. The front surface and the back surface of the resistor 1 are electrically connected. As described above, the resistor 1 is made of a base material capable of elastic deformation, to which a mixture containing a conductive polymer and a binder resin is fixed. Specifically, as the resistor 1, there is a conductive cloth in which a fibrous conductor (conductive fiber having a mixture attached to the fiber) is used as at least one of warp and weft. It is also possible to use a cloth-like conductor (conductive cloth having a mixture adhered to the cloth) as the resistor 1. Since the conductive polymer is uniformly distributed in these conductive cloths, the conductive surface of the conductive cloth has substantially uniform conductivity. In addition, the conductive cloth retains air permeability, flexibility, and hygroscopicity as a cloth.

  The base material is preferably a three-dimensional and thick knitted structure (woven fabric) or a woven or non-woven fabric having an overlapping structure. For example, a fabric having an elastic structure constituted by fibers in the thickness direction, such as a 2-way tricot, a 2-way tricot, and a stocking, can be given. When a tensile force is applied to the resistor 1 as described above, the conductive polymer that is uniformly fixed to the resistor 1 is compressed, stretched, and bent, so that the resistance value changes.

  Next, a change in the resistance value of the extension sensor due to a change in tension will be described in detail. FIG. 2 is a diagram showing a measurement method used in the measurement test of the present embodiment. The resistor 1 of the extension sensor is a conductive cloth having a length of 3 cm and a width of 15 cm. In this resistor 1, terminals 2a and 2b were provided at positions spaced 2 cm from the center to the left and right, respectively. In this state, the resistor 1 was pulled to the left and right in 0.5 cm increments, and the resistance value change at that time was measured with a measuring instrument 10 (Sanwa, CD731a). Probes 11a and 11b were connected between the measuring instrument 10 and the extension sensor terminals 2a and 2b. As the resistor 1, an eighth embodiment described later is used. FIG. 3 is a photograph of the resistor 1 taken from above. The results measured under the above conditions are shown in Table 1.

  The measurement results are shown in FIG. The pulling distance ΔL shown in Table 1 and FIG. 4 indicates the left or right pulling distance. Therefore, if the tensile distance ΔL is 0.5 cm, the total left and right tensile distance is 1 cm. According to Table 1 and FIG. 4, it can be seen that the resistance value of the resistor 1 shown in FIG. 3 changes from about 5 to 15 kΩ by pulling left and right. The resistance value monotonously increases until the tensile distance ΔL is 2 cm, but it can be seen that the resistance change is saturated at a tensile distance ΔL longer than this. This phenomenon indicates that the resistor 1 shown in FIG. 3 has an elastic region and a plastic region in the resistance value.

  As described above, according to the extension sensor of the present embodiment, the conductive polymer is fixed to a base material that can be elastically deformed in a state of being kneaded in a solidified (cured) binder resin (polymer). Since the resistor 1 is used as the resistor 1, the structural breakdown of the resistor 1 hardly occurs, and high conductivity can be maintained over a long period of time. Moreover, the flexible resistor 1 can be formed by utilizing the inherent flexibility of the base material (fiber or cloth). Despite the state in which the conductive polymer is kneaded into the binder resin, the conductivity of the conductive polymer is so high that it can be used practically without any problem, and hardly deteriorates. For this reason, since the conductive polymer contained in the solidified binder resin can transmit a weak change in electric signal due to a resistance change, high-sensitivity and high-accuracy signal transmission / reception is performed between the extension sensor and the external device. be able to. Furthermore, since the mechanical strength of the resistor 1 is increased by the solidified binder resin, the possibility that the resistor 1 is damaged by an external force in a state where the extension sensor is attached to the human body can be reduced. It is possible to realize an extension sensor excellent in performance.

  In addition, the extension sensor according to the present embodiment has high wearability required for a wearable device that is used in contact with the skin for a long period of time, that is, touch feeling, thinness, flexibility, strength, and breathability. Comfort at the time of wearing that each request is complicated can be realized. When the base material of the resistor 1 is a fiber, the comfort at the time of wearing can be realized by incorporating the resistor 1 into clothing. Needless to say, the cloth-like resistor 1 may be incorporated into clothing.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. In the first embodiment, the resistance value changes when the resistor 1 of the extension sensor is pulled. At this time, when the tensile distance is large, the resistance value of the extension sensor becomes plastic, that is, hysteresis, as described in Table 1 and FIG. However, when the conductive cloth as shown in FIG. 3 is used as an extension sensor, it is desirable that the resistance value characteristic with respect to the tensile distance is not hysteresis.

  Therefore, in the present embodiment, a stopper structure for preventing the characteristic plasticity is introduced into the resistor 1 of the extension sensor. FIG. 5 is a plan view showing the configuration of the extension sensor of the present embodiment. In the present embodiment, the non-plastic yarn 3 is knitted into the conductive cloth constituting the resistor 1. Thereby, in this Embodiment, since the non-plastic thread | yarn 3 suppresses tension | tensile_strength in the elastic region of the resistor 1, it can avoid that the resistance value characteristic of the resistor 1 becomes plastic.

[Third Embodiment]
Next, an application example of the extension sensor will be described. By utilizing the change in the resistance value when the extension sensor is extended as described above, for example, the bending angle of the joint of the human body can be measured. FIG. 6 is a diagram illustrating a state in which an extension sensor is wound around an elbow of a human body. As shown in FIG. 7, the resistor 1 of the extension sensor is a tube made of a conductive cloth having a length of 25 cm and a width of 20 cm. When the conductive cloth is formed into a cylindrical shape, the end of the conductive cloth is thermocompression bonded with the iron tape 4.

  As shown in FIG. 6, the measuring sensor is mounted so that the resistor 1 of the extension sensor is placed at the center of the elbow of the human body 12, and the terminals 2 a and 2 b of the extension sensor are connected to the measuring device 13. Thereby, the bending angle of the elbow joint, that is, the change in the resistance value due to the tension applied to the resistor 1 of the extension sensor is measured by the measuring device 13. As the resistor 1, an eighth embodiment described later is used.

  Here, when each subject wears the extension sensor for the first time, the correlation between the elbow joint flexion angle and the resistance value of the extension sensor is examined in advance, and the resistance value corresponding to each flexion angle of the elbow joint is measured. The information is stored in a lookup table (not shown) of the device 13. During the subsequent operation, the information acquisition means (not shown) of the measuring device 13 refers to the lookup table based on the resistance value of the extension sensor and acquires information on the bending angle corresponding to the resistance value. Thereby, the measuring device 13 can present the bending angle of the joint of the subject's elbow to the measurer. Such a measuring device 13 can be realized by a CPU, a storage device, a computer including an interface including a resistance value measuring unit, and a program for controlling these hardware resources. The CPU performs the above-described measurement according to the program stored in the storage device.

In the method of measuring the bending angle of the joint according to the present embodiment, only the elbow joint of the human body has been described. However, the present invention is not limited to this, and it can be applied to other joints by a similar method. Further, not the relationship between the change in the bending angle and the resistance value of the extension sensor, but the relationship between the change in length and the resistance value of the extension sensor may be stored in the lookup table.
Further, by using an extension sensor together with a known acceleration sensor and angular velocity gyro sensor, it is possible to perform not only joint bending but also advanced motion capture such as sitting, standing, walking, and running.

  In addition, since the extension sensors of the first to third embodiments are thin and flexible, they are excellent in wearability. Furthermore, when the conductive surface of the resistor 1 constituting the extension sensor has appropriate hydrophilicity, the conductivity when the extension sensor is installed so as to directly touch the skin is further improved. In addition, when the extension sensor is installed so as to directly touch the skin, in addition to the function as the extension sensor, it can also have a function of acquiring a biological signal as a biological electrode. In addition, since the extension sensors of the first to third embodiments operate with a simple circuit, their sensitivity characteristics can be easily adjusted.

[Fourth Embodiment]
Next, the manufacturing method of the expansion | extension sensor of 1st-3rd embodiment is demonstrated. Resistor 1 of the extension sensor according to the first to third embodiments includes a resin including at least one of a binder resin and a polymerizable compound (monomer) constituting the binder resin, and a conductive polymer as a conductive filler. The composition is adhered to a substrate (fiber or cloth) that can be elastically deformed, and the resin composition is solidified or polymerized.

  The conductive polymer, the binder resin, the polymerizable compound (monomer) constituting the binder resin, and the base material capable of elastic deformation are as described in the first to third embodiments. For this reason, it will not be described repeatedly here.

  The resin composition may contain a solvent in order to dissolve the conductive polymer, the binder resin and the monomer, or to adjust the viscosity. The type of the solvent is not particularly limited, and is appropriately selected according to the type and purpose of the resin. The mixing ratio of the solvent and the resin is not particularly limited, and is appropriately adjusted so that the resin composition can be attached to the base material (fiber or cloth). In addition to the solvent, the resin composition contains an auxiliary agent such as a polymerization initiator, a polymerization accelerator, a cross-linking agent that cross-links resins, a stabilizer, an antioxidant, a pigment, and a filler depending on the purpose. May be.

  The content of the conductive polymer in the resin composition before solidification is not particularly limited as long as the mixture obtained by solidifying the resin composition maintains conductivity. For example, 0.01 to 10 % By weight is preferred, 0.05 to 5% by weight is more preferred, and 0.1 to 3% by weight is even more preferred.

  The content of the binder resin in the resin composition before solidification is not particularly limited as long as the mixture obtained by solidifying the resin composition maintains electrical conductivity. For example, 0.05 to 50% by weight Is preferable, 0.1 to 25% by weight is more preferable, and 3 to 8% by weight is further preferable.

  The total content of the conductive polymer and the binder resin in the resin composition before solidification is not particularly limited as long as the mixture obtained by solidifying the resin composition maintains conductivity, for example, 0.06-60 weight% is preferable, 0.15-30 weight% is more preferable, and 4-8 weight% is still more preferable.

  The weight ratio of the conductive polymer and the binder resin in the resin composition before solidification is not particularly limited as long as the mixture obtained by solidifying the resin composition maintains the conductivity. For example, the binder resin Weight / weight of conductive polymer = 1 to 100, preferably 2 to 10, more preferably 4 to 6.

  When the content of the conductive polymer and the binder resin in the resin composition is set to the above preferable range, and the balance is a solvent, the viscosity of the resin composition becomes appropriate, and the resin composition is attached to the substrate. The workability at the time is improved, and it can be made to adhere uniformly.

  The method for adhering the resin composition to the substrate is not particularly limited, and known methods such as coating, printing, dipping, spraying, and dropping can be applied. After the resin composition is attached to the substrate, the resin composition can be solidified (cured) or polymerized to change the resin composition to the mixture described in the first embodiment, and stretched. A sensor resistor 1 is obtained.

  The method for solidifying (curing) the resin composition is not particularly limited as long as it is a method in which the mixture is fixed to a substrate (fiber or cloth). For example, a method of evaporating a solvent contained in a resin composition and drying the resin composition, a method of polymerizing the monomer contained in the resin composition to form a binder resin in the resin composition, and a resin composition The binder resin to be crosslinked with a crosslinking agent to form a three-dimensional network structure in the resin composition, the conductive resins contained in the resin composition are crosslinked with a crosslinking agent to form a three-dimensional network in the resin composition Examples thereof include a method of forming a structure, and a method of forming a three-dimensional network structure in a resin composition by crosslinking binder resins and conductive resins contained in a resin composition with a crosslinking agent.

  Here, “solidifying” the resin composition means that the resin composition becomes the mixture, and the mixture changes to a state in which a substrate (fiber or cloth) can be coated. Therefore, the solidified resin composition (the obtained mixture) may or may not have a solid feeling (rigidity) like a plastic molded product. Moreover, the solidified resin composition may have elasticity like rubber or may have flexibility like gel.

Examples of the method of drying the resin composition include a method of blowing warm air and a method of heating.
Examples of the method of polymerizing the monomer contained in the resin composition include a method of thermosetting by heating, a method of photocuring by irradiating light such as UV or visible light, and the like. In this case, it is preferable to add a conventionally known curing initiator or curing accelerator to the resin composition. Moreover, when the base material to which the resin composition is attached is thick, the thermal curing is preferable to the photocuring because the polymerization efficiency is increased.
The method for crosslinking the resins contained in the resin composition is not particularly limited, and can be performed by a conventional method.

  By adjusting the content of the conductive polymer contained in the resin composition, the conductivity of the obtained conductor can be adjusted. Usually, the electrical conductivity of the resistor 1 can be increased as the content of the conductive polymer is increased.

  By selecting the type and content of the binder resin contained in the resin composition according to the purpose, the properties of the obtained resistor 1 can be adjusted. For example, hydrophilicity (hydrophobicity), wettability, water absorption, water resistance, abrasion resistance, peel resistance, chemical resistance, heat resistance, and the like can be adjusted. Usually, the higher the content of the binder resin, the more the properties of the binder resin can be reflected in the resistor 1.

The manufacturing method of the present embodiment does not require a special and expensive device, and can mass-produce the resistor 1 at low cost and high efficiency.
When the base material which comprises the resistor 1 is a fiber, since the said fiber can be processed into a desired form, the resistor 1 of a desired shape can be manufactured. By incorporating the fibrous or cloth-like resistor 1 into a conventional clothing product, it is possible to install a wiring made of the resistor 1 or a conductive surface made of the resistor 1 in the clothing. .

  When the base material constituting the resistor 1 is a fabric, the resistor 1 having a conductive surface having a desired shape can be manufactured by printing the resin composition on a desired region of the fabric. If the shape of the conductive surface is an elongated rectangle or line, the conductive surface can also function as an electrical wiring. Furthermore, it is possible to form a complicated electric circuit or an electric binding part (connector part) on the cloth by the printing or the like.

  Next, the present invention will be described in more detail, but the present invention is not limited to the following embodiments.

[Fifth Embodiment]
A mixed solution (resin composition) containing 52% by weight of ethanol, 42% by weight of water, 5% by weight of polymethacrylic acid, and 1% by weight of PEDOT-PSS was prepared. A mixed fabric (5 cm × 10 cm) as a base material was immersed in this mixed solution for 5 minutes, and then dried by applying warm air to the mixed fabric using a dryer to obtain a resistor 1 in which the mixed solution was solidified. . When a probe of a resistance measuring instrument was applied to the surface of the resistor 1 and measured with a direct current of 5 V, the electric resistance value of the resistor 1 in a state where no tension was applied was 200 kΩ / cm.

  In this embodiment, “SILKY DRY” (registered trademark) (First Reading Co., Ltd., manufactured by Toray Industries, Inc.) made of polyester (containing 87%) and polyurethane (containing 13%) is used as a blended fabric as a base material. It was. Ethanol manufactured by Kanto Chemical Co. was used. As the water, purified water produced by MILLI-Q (registered trademark) (manufactured by Merck) was used. The polymethacrylic acid used was made by Scientific Polymer Products Inc. As PEDOT-PSS, Clevious P (manufactured by Heraeus, Germany) was used.

[Sixth Embodiment]
Resistor 1 of the extension sensor was produced using 5% by weight of polymethylmethacrylic acid (manufactured by Aldrich Chemical Co.) instead of the polymethacrylic acid of the fifth embodiment. The other components of the mixed liquid are as described in the fifth embodiment. In this case, the electric resistance value of the resistor 1 in a state where no tension was applied was 1 MΩ / cm.

[Seventh Embodiment]
The extension sensor resistor 1 was prepared using 5 wt% polyacrylic acid (manufactured by Scientific Polymer Products) instead of the polymethacrylic acid of the fifth embodiment. The other components of the mixed liquid are as described in the fifth embodiment. In this case, the electric resistance value of the resistor 1 in a state where no tension was applied was 100 kΩ / cm.

[Eighth Embodiment]
A mixed liquid was prepared using 5% by weight of polyvinyl alcohol (Wako Pure Chemical Industries) in place of the polyacrylic acid of the seventh embodiment. The other components of the mixed liquid are as described in the fifth embodiment. After the blended fabric described in the fifth embodiment is immersed in this mixed solution for 5 minutes, the blended fabric is dried with a drier and further immersed in ethanol for 5 minutes, thereby being composed of PEDOT-PSS and polyvinyl alcohol. The mixture was chemically fixed. Thereafter, the resistor 1 of the extension sensor was produced by drying with a dryer. When measured in the same manner as in the fifth embodiment, the electrical resistance value of the resistor 1 in a state where no tension was applied was 1.2 MΩ / cm.

[Ninth Embodiment]
Using a lycra (registered trademark) (manufactured by Toray Operontex Co., Ltd.), which is a stretchable cloth, as a base material, a resistor 1 provided with conductivity was produced by the same method as in the fifth embodiment. The size of the resistor 1 was 15 cm wide × 3 cm long and 600 μm thick.

  The configurations and combinations thereof in the embodiments described above are examples, and the addition, omission, replacement, and other changes of the configurations can be made without departing from the spirit of the present invention. Further, the present invention is not limited by each embodiment, and is limited only by the scope of the claims.

  The present invention can be widely used in a wide range of fields such as motion capture, medical care, health promotion, information technology, and wearable computers.

  DESCRIPTION OF SYMBOLS 1 ... Resistor, 2a, 2b ... Terminal, 3 ... Nonplastic yarn, 4 ... Iron tape, 10, 13 ... Measuring instrument, 11a, 11b ... Probe.

Claims (6)

A resistor composed of an elastically deformable base material, and a mixture containing a conductive polymer and a binder resin fixed to at least a part of the surface and inside of the base material;
An extension sensor comprising: a pair of terminals electrically connected to an end of the conductive surface of the resistor. The extension sensor according to claim 1, wherein
The elongation sensor, wherein the substrate is a fiber or a cloth. The extension sensor according to claim 1 or 2,
The resistor is formed in a cylindrical shape. The extension sensor according to any one of claims 1 to 3,
The extension sensor is incorporated in clothing. The extension sensor according to any one of claims 1 to 4,
The elongation sensor characterized by the base material which comprises the said resistor is equipped with the stopper structure for suppressing reaching | attaining a plastic deformation area | region when tension | tensile_strength is applied from the outside. The extension sensor according to any one of claims 1 to 5,
A table for storing in advance the relationship between the change in length or angle of the measurement object to which the extension sensor is attached and the resistance value of the resistor;
A measurement apparatus comprising: an information acquisition unit that acquires information on a change in length or an angle corresponding to the resistance value by referring to the table based on the resistance value of the resistor.