JP2022185958A - Seat for movable body, biological information detector, and control system - Google Patents

Abstract

To provide a seat for a movable body, capable of accurately acquiring biological information even in an environment which can be heated to a high temperature, to provide a biological information detector, and a control system.SOLUTION: A seat for a movable body comprises: support bodies disposed in the movable body and supporting a human body; and piezoelectric base materials disposed respectively in the support bodies and detecting pressure received from the human body. The piezoelectric base material comprises: an axial inner conductor; and an elongated piezoelectric substance coaxially disposed around the inner conductor, and containing an optical active polypeptide.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to a seat for a mobile body, a biological information detection device, and a control system.

2. Description of the Related Art In recent years, an apparatus has been disclosed in which a sensor is installed in a seat of a vehicle and biometric information of the driver is detected from the seat in order to detect the condition of the driver who drives the vehicle.

JP 2016-146953 A

The technique described in Patent Literature 1 is characterized by acquiring biometric information using a pressure-sensitive sensor to which film-like polyvinylidene fluoride (hereinafter referred to as "PVDF") is applied. However, the PVDF described in Patent Literature 1 is a ferroelectric material and thus has pyroelectricity, and the sensitivity of the sensor may fluctuate due to temperature changes. Therefore, the pressure-sensitive sensor to which PVDF is applied has unstable sensor sensitivity in an environment that changes to a high temperature such as a seat installed in a vehicle, and it is not always possible to acquire biometric information with high accuracy.

SUMMARY OF THE INVENTION The present invention has been made in view of the above facts, and provides a seat for a moving body, a biometric information detection device, and a control system that can accurately acquire biometric information even in an environment that changes to a high temperature. for the purpose.

Specific means for achieving the above object are as follows.

<1> a support provided in a moving body for supporting a human body;
a piezoelectric substrate provided on the support and detecting pressure received from the human body;
The piezoelectric substrate is
an axial inner conductor;
an elongated piezoelectric body provided coaxially around the inner conductor and containing an optically active polypeptide;
A seat for a moving body.

<2> The piezoelectric base material is
the length direction of the elongated piezoelectric body and the main orientation direction of the optically active polypeptide are substantially parallel,
The sheet for a moving object according to <1>.

<3> The degree of orientation F of the optically active polypeptide determined by the following formula (a) from X-ray diffraction measurement is 0.50 or more and less than 1.00.
The moving body sheet according to <1> or <2>.
Degree of orientation F=(180°−α)/180° Formula (a) [In formula (a), α represents the half width (°) of the peak derived from the orientation. ]

<4> The long piezoelectric body is spirally wound in one direction,
The moving body seat according to any one of <1> to <3>.

<5> The piezoelectric base material further comprises an outer conductor on the outer circumference,
The moving body sheet according to any one of <1> to <4>.

<6> The piezoelectric base further comprises an insulator on the outer circumference of the outer conductor.
The sheet for a moving object according to <5>.

<7> the optically active polypeptide comprises at least one of silk and spider silk,
The moving body sheet according to any one of <1> to <6>.

<8> The moving body sheet according to any one of <1> to <7>;
a detection unit that detects a signal corresponding to the pressure received by the piezoelectric substrate;
a detection unit that detects biological information in the human body based on the signal detected by the detection unit;
A biological information detection device comprising:

<9> The support includes a plurality of piezoelectric substrates,
The detection unit independently detects a signal from each piezoelectric base material,
The detection unit detects position information indicating a position where the human body is in contact from the signals detected from each piezoelectric base material.
The biological information detection device according to <8>.

<10> The biological information detecting device according to <8> or <9>;
a control device for controlling devices in the moving object based on the information detected by the biological information detection device;
A control system with

<11> The control device controls the device according to information related to the heartbeat of the human body obtained from the biological information.
The control system according to <10>.

ADVANTAGE OF THE INVENTION According to this invention, biometric information can be acquired accurately even in the environment which changes to high temperature.

It is a block diagram showing an example of a control system concerning each embodiment. It is a perspective view which shows an example of the sheet|seat for moving bodies which concerns on each embodiment. FIG. 3 is a cross-sectional view showing an example of a moving body sheet for explaining the arrangement of piezoelectric substrates according to each embodiment. FIG. 2 is a projection view showing an example of a moving body sheet for explaining the arrangement of piezoelectric substrates according to the first embodiment; It is a block diagram showing an example of hardware constitutions of a living body information detecting device concerning each embodiment. It is a block diagram which shows an example of the hardware constitutions of the control apparatus which concerns on each embodiment. It is a block diagram showing an example of functional composition of a control system concerning a 1st embodiment. FIG. 2 is a schematic side view schematically showing a piezoelectric base material according to each embodiment; 9 is a cross-sectional view taken along the line X-X' of FIG. 8 in the piezoelectric base material according to each embodiment. FIG. FIG. 5 is a schematic side view schematically showing a piezoelectric base material according to a modified example of each embodiment; FIG. 11 is a projection view showing an example of a moving body sheet for explaining the arrangement of piezoelectric substrates according to the second embodiment. FIG. 11 is a projection view showing an example of a moving body sheet for explaining the arrangement of piezoelectric substrates according to a modification of the second embodiment. FIG. 11 is a projection view showing an example of a moving body sheet for explaining the arrangement of piezoelectric substrates according to the third embodiment. FIG. 11 is a block diagram showing an example of a functional configuration of a control system according to a third embodiment; FIG. FIG. 10 is a projection view showing an example of a moving body sheet for explaining the arrangement of piezoelectric substrates according to a modification of the third embodiment. FIG. 11 is a projection view showing an example of a moving body sheet for explaining the arrangement of piezoelectric substrates according to the fourth embodiment. FIG. 11 is a projection view showing an example of a moving body sheet for explaining the arrangement of piezoelectric substrates according to the fifth embodiment. FIG. 3 is a block diagram showing an example of a detection circuit that detects biological information from a piezoelectric base material according to an embodiment; 4 is a graph showing an example of biometric information detected from a piezoelectric base material according to an example.

Embodiments of the present invention will be described below. The present disclosure is not limited to the following embodiments.
In this specification, a numerical range represented by "to" means a range including the numerical values before and after "to" as lower and upper limits.
In this specification, the "surface" of a member means the "principal surface" of the member unless otherwise specified.
As used herein, thickness, width, and length satisfy the relationship thickness<width<length, as is commonly defined.
In this specification, the angle formed by two line segments is expressed in the range of 0° or more and 90° or less.
In this specification, "film" is a concept that includes not only what is generally called "film" but also what is generally called "sheet".
When embodiments are described herein with reference to the drawings, the configurations of the embodiments are not limited to the configurations shown in the drawings. In addition, the sizes of the members in each drawing are conceptual, and the relative relationship between the sizes of the members is not limited to this.
In this specification, a "vehicle" will be described as an example of a mobile object. However, it is not limited to this. The mobile body may be an aircraft, a ship, or any vehicle provided that it has a seat and is movable.

[First embodiment]
The control system will be described with reference to FIGS. 1 to 10. FIG.

<Configuration of control system>
As an example, as shown in FIG. 1, a control system 1 according to this embodiment is mounted on a vehicle 2 and includes a biological information detection device 10, a control device 100, and a device 200. As shown in FIG. The biological information detection device 10 includes a vehicle seat 20 and detects biological information of a seated occupant from a sensor installed in the vehicle seat 20 . The control device 100 controls the device 200 mounted on the vehicle 2 using the information detected by the biological information detection device 10 . Here, the device 200 includes devices such as air conditioners, seat heaters, lighting, drowsiness prevention devices, diffusers, and audio devices in the vehicle, and actuators for operating steering, throttle, brakes, and the like. For example, the control device 100 performs control such as activation of air conditioning, generation of an odor to prevent drowsiness, notification to passengers, and stopping of the vehicle, according to the detected biological information.

<Structure of Seat for Moving Body>
With reference to FIG. 2, the moving body seat 20 will be described. The moving body seat 20 is provided in a vehicle as a moving body so as to face forward of the vehicle when an occupant is seated. Therefore, the seat width direction coincides with the vehicle width direction, the seat depth direction coincides with the vehicle front-rear direction, and the seat height direction coincides with the vehicle vertical direction. In the following description, the seat direction is simply defined as the width direction, the seat depth direction is simply defined as the depth direction, and the seat height direction is simply defined as the height direction.

As an example, as shown in FIG. 2 , the vehicle seat 20 according to this embodiment includes a seat cushion 21 , a seat back 22 and a sensor unit 23 . The seat cushion 21 and the seat back 22 are pressurized by a vehicle occupant sitting on them and coming into contact with them. Here, the seat cushion 21 and the seat back 22 are examples of a "support" that supports the human body. As shown in FIG. 3, the seat cushion 21 and the seat back 22 each include a frame (not shown), an elastic body 24 such as urethane or sponge rubber provided on the frame, and a skin 25 covering the surface of the elastic body 24. , is composed of

The sensor unit 23 includes a piezoelectric substrate 50 that generates a voltage when pressure P is input, and wiring 29 that is connected to the piezoelectric substrate 50 and will be described later. As shown in FIG. 3, the piezoelectric base material 50 is installed on the elastic body 24 that constitutes the seat cushion 21 and the seat back 22, and can detect the pressure P received from the occupant's body. Specifically, the piezoelectric substrate 50 is placed inside the cut 26 formed in the upper portion of the elastic body 24 and on the sponge rubber 27 provided at the bottom of the cut 26 . Thereby, the piezoelectric substrate 50 can detect the pressure P of the occupant's body received from the surfaces of the seat cushion 21 and the seat back 22 . The piezoelectric substrate 50 may be placed directly under the skin 25 and on the surface of the elastic body 24, or the piezoelectric substrate 50 may be placed without using the elastic body 24 such as sponge rubber. good too.

As an example, as shown in FIG. 4, the piezoelectric substrate 50 is arranged at the center of the seat cushion 21 in the depth direction, and the piezoelectric substrate 50 is arranged at the center of the seat back 22 in the width direction. Here, FIG. 4A shows a plan view of the moving body seat 20 seen from above in the height direction, and FIG. A front view of the seat 20 is shown.

Specifically, as shown in FIG. 4A, the piezoelectric base material 50 is arranged along the width direction at the center of the seat cushion 21 in the depth direction directly under the skin of the seat cushion 21 . Further, as shown in FIG. 4(b), a piezoelectric substrate 50 is arranged along the height direction in the center of the width direction of the seat back 22 directly below the skin 25 of the seat back 22. As shown in FIG.

In this embodiment, the configuration in which the piezoelectric substrates 50 are arranged linearly in the width direction and the height direction has been described. However, it is not limited to this. For example, in the seat cushion 21 shown in FIG. 3, the piezoelectric substrate 50 may be arranged with the notch 26 curved toward the depth side with respect to the depth direction. Further, in the seat cushion 21, the piezoelectric base material 50 may be arranged by bending the cutout 26 downward in the height direction so that the arrangement becomes deeper as it approaches the center in the width direction. Further, in the seat cushion 21 and the seat back 22 , the skin 25 and the sponge rubber 27 in contact with the piezoelectric substrate 50 may be uneven so as to improve the detection sensitivity of the piezoelectric substrate 50 . Also, the piezoelectric base material 50 may be arranged at a portion of the seat belt with which the occupant's upper body comes into contact.

<Configuration of biological information detection device>
Next, a hardware configuration of the biological information detection device 10 will be described with reference to FIG. 5 . The biological information detection device 10 detects an output signal from the piezoelectric substrate 50 . As shown in FIG. 5, the biological information detecting device 10 includes an AD converter 28 that converts the voltage output, which is an analog signal output from the piezoelectric substrate 50, into a digital signal, and a digital signal of each piezoelectric substrate 50 that has been converted. and a vehicle-mounted device 30 that detects a signal. The AD converter 28 is provided with a plurality of input terminals for inputting analog signals, and the piezoelectric substrate 50 is electrically connected to each input terminal via the wiring 29 .
The vehicle-mounted device 30 includes a CPU (Central Processing Unit) 31, a ROM (Read Only Memory) 32, a RAM (Random Access Memory) 33, a storage 34, a communication I/F (Inter Face) 35, and an input/output I/F 36. consists of The CPU 31 , ROM 32 , RAM 33 , storage 34 , communication I/F 35 , and input/output I/F 36 are connected via a bus 37 so as to be able to communicate with each other.

The CPU 31 is a central processing unit that executes various programs and controls each section. That is, the CPU 31 reads a program from the ROM 32 or the storage 34 and executes the program using the RAM 33 as a work area. In this embodiment, execution programs for executing various processes are stored in the storage 34 . The CPU 31 functions as the detection unit 41 and the detection unit 42A shown in FIG. 7 by executing the execution program.
The ROM 32 stores various programs and various data. The RAM 33 temporarily stores programs or data as a work area. The storage 34 as a storage unit is configured by a HDD (Hard Disk Drive) or SSD (Solid State Drive), and stores various programs including an operating system and various data.

The communication I/F 35 is an interface for communicating with the control device 100, and performs communication according to the CAN (Controller Area Network) protocol. Note that the communication I/F 35 may apply a communication standard based on Ethernet (registered trademark). Communication I/F 35 is connected to an external bus (not shown). In other words, data transmitted/received between the biological information detection device 10 and the control device 100 is transmitted/received as a communication frame based on the CAN protocol on an external bus (not shown). Here, the communication I/F 35 may be directly connected to the device 200 without going through the control device 100 to transmit and receive data between the biological information detection device 10 and the device 200 .

<Configuration of control device>
As shown in FIG. 6, the control device 100 includes a CPU 101, a ROM 102, a RAM 103, a storage 104, an input/output unit 105, a display unit 106, and a communication I/F 107. In the control device 100, a CPU 101, a ROM 102, a RAM 103, a storage 104, an input/output unit 105, a display unit 106, and a communication I/F 107 are connected via a bus 108 so as to be able to communicate with each other.

A CPU 101 is a central processing unit that executes various programs and controls each section. That is, the CPU 101 reads a program from the ROM 102 and executes the program using the RAM 103 as a work area.

The ROM 102 stores various programs and various data. A control program for controlling the control device 100 is stored in the ROM 102 of the present embodiment.
The RAM 103 temporarily stores programs or data as a work area.

The storage 104 is, for example, an HDD, SSD, flash memory, or the like. Note that the storage 104 may store control programs and the like. The input/output unit 105 is, for example, a mouse, keyboard, touch panel, speaker, and the like. The display unit 106 displays a notification to the passenger according to the detected biological information.

Communication I/F 107 is an interface for connecting biological information detection device 10 , control device 100 , and device 200 . The interface performs communication according to the CAN protocol. In addition, in the communication I/F 107, a communication standard by Ethernet (registered trademark) may be applied. Communication I/F 107 is connected to an external bus (not shown). That is, data transmitted/received between the biological information detection device 10, the control device 100, and the device 200 is transmitted/received as a communication frame based on the CAN protocol on an external bus (not shown).

<Functional configuration of biological information detection device and control device>
FIG. 7 is a block diagram showing an example of functional configurations of the biological information detection device 10 and the control device 100. As shown in FIG. As shown in FIG. 7, the biological information detection device 10 has a detection section 41 and a detection section 42A. Each functional configuration is realized by the CPU 31 reading an execution program stored in the storage 34 and executing it.

The detection unit 41 has a function of detecting a digital signal related to each piezoelectric substrate 50 output from the AD converter 28 via the input/output I/F 36 .

The detector 42A has a function of detecting biological information such as respiration and pulse from the magnitude and period of the digital signal detected by the detector 41 .

Further, as shown in FIG. 7, the control device 100 has an acquisition unit 111A and a control unit 112A. Each functional configuration is realized by the CPU 101 reading an execution program stored in the storage 104 and executing it.

The acquisition unit 111A has a function of acquiring biometric information from the biometric information detection device 10 .

112 A of control parts have the function to control the apparatus 200 using the acquired biometric information. For example, the control unit 112A transmits an instruction to execute processing to each device 200 according to the biometric information. Specifically, the control unit 112A detects fluctuations in the intervals between heartbeats from the biological information, and when the fluctuations in the heartbeats become smaller (the intervals between heartbeats are stable), the occupant is sleepy. It determines that there is, and transmits an instruction to brake the actuator as the device 200 . The heartbeat fluctuation may be obtained by directly measuring the heartbeat interval, or by converting the heartbeat interval into a frequency. In addition, the control unit 112A detects the size and number of heartbeats from the biological information, and if the size of the heartbeat is greater than the average value for the occupant and the number of heartbeats in a predetermined period is greater than the average value for the occupant, It is determined that the occupant is in a tense state, and an instruction to apply the brake to the actuator as the device 200 is transmitted.

<Piezoelectric substrate>
The piezoelectric substrate of this embodiment includes an axial inner conductor and an elongated piezoelectric body coaxially provided around the inner conductor and containing an optically active polypeptide.

In the piezoelectric base material of the present embodiment, the elongated piezoelectric body is provided coaxially around the inner conductor, and the elongated piezoelectric body contains the optically active polypeptide. (piezoelectric sensitivity) is expressed.
In the piezoelectric substrate of this embodiment, a piezoelectric body is spirally wound in one direction around an inner conductor.

Furthermore, since the piezoelectric substrate of the present embodiment contains an optically active polypeptide that is excellent in hydrolysis resistance in a high-temperature, high-humidity environment, compared with a piezoelectric substrate using polylactic acid, for example, Excellent durability in wet environments).
In this specification, "excellent in durability" means that a decrease in piezoelectric sensitivity is suppressed (especially in a high-temperature and high-humidity environment).

<Piezoelectric material>
The piezoelectric substrate of this embodiment includes an elongated piezoelectric body.
The orientation degree F of the elongated piezoelectric body is in the range of 0.50 or more and less than 1.00.
The degree of orientation F of the piezoelectric material is a value obtained by the following formula (a) from X-ray diffraction measurement, and means the degree of c-axis orientation.

Orientation F=(180°-α)/180°... Formula (a)
[In the formula (a), α represents the half width (°) of the orientation-derived peak. ]

The degree of orientation F is an index indicating the degree of orientation of the optically active polypeptide contained in the piezoelectric material.
In this embodiment, the fact that the orientation degree F of the elongated piezoelectric body is 0.50 or more contributes to the development of piezoelectricity.
The fact that the orientation degree F of the elongated piezoelectric body is less than 1.00 contributes to the productivity of the piezoelectric body.
The orientation degree F of the elongated piezoelectric body is preferably 0.50 or more and 0.99 or less, more preferably 0.70 or more and 0.98 or less, and 0.80 or more and 0.97 or less. It is particularly preferred to have

In the present embodiment, the fact that the length direction of the piezoelectric body and the main orientation direction of the optically active polypeptide contained in the piezoelectric body are substantially parallel also contributes to the development of piezoelectricity.
The fact that the length direction of the piezoelectric body and the main orientation direction of the optically active polypeptide contained in the piezoelectric body are substantially parallel also has the advantage that the piezoelectric body has excellent tensile strength in the length direction. . Therefore, when the piezoelectric body is spirally wound, the piezoelectric body is less likely to break.
In this specification, the term “substantially parallel” means that the angle formed by the two line segments is 0° or more and less than 30° when the angle formed by the two line segments is expressed in the range of 0° or more and 90° or less. (Preferably 0° or more and 22.5° or less, more preferably 0° or more and 10° or less, still more preferably 0° or more and 5° or less, particularly preferably 0° or more and 3° or less).
For example, when the piezoelectric body is silk or spider silk, in the process of producing silk or spider silk, the length direction of the piezoelectric body (silk or spider silk) and the optically active polypeptide (for example, fibroin) contained in the piezoelectric body or spider silk protein) are substantially parallel to each other.

The fact that the length direction of the piezoelectric body and the main orientation direction of the optically active polypeptide contained in the piezoelectric body are substantially parallel means that in X-ray diffraction measurement, the installation direction of the sample and the azimuth angle of the crystal peak can be verified by comparing .

In this embodiment, the inclusion of an optically active polypeptide in the piezoelectric also contributes to the development of piezoelectricity.
In addition, as described above, optically active polypeptides are excellent in hydrolysis resistance. Excellent material durability.

In addition, since the piezoelectric body including PVDF has high pyroelectricity, the change in output of the amount of charge due to temperature change is large. On the other hand, the piezoelectric body containing the optically active polypeptide of the present embodiment has a smaller change in the output of the charge amount due to temperature changes, and the output of the charge amount is more stable than the piezoelectric body containing PVDF. Excellent in points.
On the other hand, a piezoelectric body containing polylactic acid tends to lower its sensor sensitivity when the temperature rises above a predetermined temperature. In contrast, the piezoelectric body containing the optically active polypeptide of the present embodiment has more stable sensor sensitivity than the piezoelectric body containing polylactic acid even when the temperature is higher than a predetermined temperature. Excellent in points.
Therefore, the piezoelectric body of the present embodiment has excellent sensitivity and is suitable for use in detecting biological information from the human body when placed in an environment that changes to a high temperature.

In addition, as described above, since the optically active polypeptide does not have pyroelectricity, the inclusion of the optically active polypeptide in the piezoelectric material is advantageous in that the piezoelectric material and the piezoelectric base material are more advantageous than the piezoelectric material containing PVDF as a main component. Excellent durability.

As used herein, an optically active polypeptide means a polypeptide having optical activity (that is, a polypeptide having an asymmetric carbon atom and having a biased abundance of optical isomers).
The optically active polypeptide preferably has a β-sheet structure from the viewpoint of piezoelectricity and strength.
Optically active polypeptides include animal proteins having optical activity (eg, fibroin, sericin, collagen, keratin, elastin, spider silk protein, etc.).
The optically active polypeptide preferably contains at least one of fibroin and spider silk protein, and particularly preferably consists of at least one of fibroin and spider silk protein.

The spider silk protein is not particularly limited as long as it is a natural spider silk protein or derived from or similar to a natural spider silk protein (hereinafter collectively referred to as "origin").
Here, "derived from natural spider silk protein" means having an amino acid sequence that is the same as or similar to the repeating sequence of amino acids that natural spider silk protein has.
"Those derived from natural spider silk proteins" include, for example, recombinant spider silk proteins, mutants of natural spider silk proteins, analogues of natural spider silk proteins, derivatives of natural spider silk proteins, and the like.

From the viewpoint of excellent toughness, the spider silk protein is preferably a major duct dragline protein produced in the greater vasculature gland of spiders or a spider silk protein derived from the major duct dragline protein.
Major duct dragline proteins include MaSp1 or MaSp2, which are major pituitary gland spidroins derived from Nephila clavipes, ADF3 or ADF4 derived from Araneus diadematus, and the like.

The spider silk protein may be a spider silk protein produced in the arachnoid glands of spiders or a spider silk protein derived from the silker silk protein.
Small duct dragline proteins include MiSp1 and MiSp2, which are small humeral gland spidroins derived from Nephila clavipes.

Alternatively, the spider silk protein may be a weft protein produced in the flagelliform gland of spiders or a spider silk protein derived from this weft protein.
Examples of the weft protein include flagelliform silk protein derived from Nephila clavipes.

Examples of the spider silk protein derived from the above-described large discharge tube dragline silk protein include recombinant spider silk proteins containing units of the amino acid sequence represented by the following formula (1).
The recombinant spider silk protein may contain 2 or more (preferably 4 or more, more preferably 6 or more) units of the amino acid sequence represented by the following formula (1).
When the recombinant spider silk protein contains two or more amino acid sequence units represented by the following formula (1), the two or more amino acid sequence units may be the same or different.

REP1-REP2 ... Formula (1)
[In the formula (1), REP1 is a polyalanine region composed mainly of alanine and represented by (X1)p, and REP2 is an amino acid sequence consisting of 10 to 200 amino acids. ]

In formula (1), REP1 is a polyalanine region composed mainly of alanine and represented by (X1)p. REP1 is preferably polyalanine.
In (X1) p, p is not particularly limited, but preferably an integer of 2-20, more preferably an integer of 4-12.
In (X1) p, X1 represents alanine (Ala), serine (Ser), or glycine (Gly).
(X1) In the polyalanine region represented by p, the total number of alanine residues is preferably 80% or more (more preferably 85% or more) of the total number of amino acid residues in the polyalanine region.
In REP1 in formula (1), the consecutively arranged alanine residues are preferably 2 or more residues, more preferably 3 residues or more, still more preferably 4 residues or more, and particularly preferably is 5 or more residues.
Further, in REP1 in formula (1), the consecutively arranged alanines are preferably 20 residues or less, more preferably 16 residues or less, still more preferably 12 residues or less, Particularly preferably, it is 10 residues or less.

In formula (1), REP2 is an amino acid sequence consisting of 10 to 200 amino acids. The total number of glycine, serine, glutamine, proline and alanine residues contained in this amino acid sequence is preferably 40% or more, more preferably 50% or more, and 60% or more of the total number of amino acid residues. Especially preferred.

Examples of spider silk proteins derived from the above-mentioned small discharge tube dragline silk proteins include recombinant spider silk proteins containing the amino acid sequence represented by the following formula (2).

REP3-REP4-REP5... Formula (2)
[In formula (2), REP3 is an amino acid sequence represented by (Gly-Gly-Z)m, REP4 is an amino acid sequence represented by (Gly-Ala)l, and REP5 is (Ala) It is the amino acid sequence represented by r.
In REP3, Z means any one amino acid.
In REP3, m is 1-4, in REP4, l is 0-4, and in REP5, r is 1-6. ]

In REP3, Z means any one amino acid, preferably one amino acid selected from the group consisting of Ala, Tyr and Gln.

The above-described recombinant spider silk protein (for example, a recombinant spider silk protein containing a unit of the amino acid sequence represented by formula (1), a recombinant spider silk protein containing an amino acid sequence represented by formula (2), etc.) is It can be produced using a host transformed with an expression vector containing a gene encoding a natural spider silk protein to be recombined.

From the viewpoint of piezoelectricity, the elongated piezoelectric body preferably contains fibers made of an optically active polypeptide.
Fibers composed of optically active polypeptides include fibers composed of optically active animal proteins (eg, silk, wool, mohair, cashmere, camel, llama, alpaca, vicuna, angora, spider silk, etc.).
From the viewpoint of piezoelectricity, the optically active polypeptide fiber preferably contains at least one of silk and spider silk, more preferably at least one of silk and spider silk.

Silk includes raw silk, refined silk, regenerated silk, and the like.
As silk, raw silk or refined silk is preferable, and refined silk is particularly preferable.
Here, refined silk means silk obtained by removing sericin from raw silk having a double structure of sericin and fibroin, and refinement means an operation to remove sericin from raw silk. The color of raw silk is dull white, but by removing sericin from raw silk (that is, refining), it changes from dull white to shiny silvery white. Refining also increases the softness of the texture.

From the viewpoint of piezoelectricity, the elongated piezoelectric body preferably contains long fibers made of an optically active polypeptide. The reason for this is thought to be that the stress applied to the piezoelectric base material is more easily transmitted to the piezoelectric body in long fibers than in short fibers.
Here, "long fiber" means a fiber having a length that can be continuously wound from one end to the other end in the longitudinal direction of the piezoelectric substrate.
Silk, wool, mohair, cashmere, camel, llama, alpaca, vicuna, angora, and spider silk described above all correspond to long fibers.
Among long fibers, silk and spider silk are preferable from the viewpoint of piezoelectricity.

When the elongated piezoelectric body contains the fiber, it is preferable that the elongated piezoelectric body includes at least one thread made of at least one fiber.
When the long piezoelectric body includes the thread, the long piezoelectric body is made of one thread, and the long piezoelectric body is an aggregate of a plurality of the threads. , etc.
The yarn may be a twisted yarn or a non-twisted yarn, but from the viewpoint of piezoelectricity, a yarn with a twist number of 500 T/m or less It is preferably several 0 T/m)).
Non-twisted yarns include a single raw yarn, an aggregate of multiple raw yarns, and the like.

The thickness of the long piezoelectric body (the thickness of the entire assembly when the long piezoelectric body is an assembly of a plurality of threads) is not particularly limited, but is preferably 0.0001 to 2 mm. , 0.001 to 1 mm, and particularly preferably 0.005 to 0.8 mm.

When the long piezoelectric body is one raw yarn or an aggregate of a plurality of raw yarns, the fineness of one raw yarn is preferably 0.01 to 10000 denier, more preferably 0.1 to 1000 denier. It is preferred, and 1 to 100 denier is particularly preferred.

In this embodiment, the elongated piezoelectric body is spirally wound.
In this embodiment, an electric charge is generated by applying a shear stress to the spirally wound long piezoelectric body. Thereby, piezoelectricity is exhibited.
Shear stress applied to the piezoelectric body can be generated, for example, by pulling the entire helically wound long piezoelectric body in the direction of the helical axis, or by pulling part of the helically wound long piezoelectric body. It can be applied by twisting (that is, twisting a part of the piezoelectric body around the helical axis), bending a part or the whole of the helically wound long piezoelectric body, or the like. .

The piezoelectric base material of the present embodiment further includes a long core material, and the long piezoelectric body is helically wound around the long core material.
Preferred aspects of the piezoelectric base material of the present embodiment are shown in the "core material, outer conductor" section below.

The elongated piezoelectric body is preferably wound at a spiral angle of 20° to 70°.
Here, the helical angle means the angle between the helical axis direction (the length direction of the core material when the core material is provided) and the length direction of the wound piezoelectric body (FIG. 8). See spiral angle β1 in the middle).
The helix angle is more preferably 25° to 65°, still more preferably 30° to 60°, and particularly preferably 35° to 55°.

The elongated piezoelectric body is preferably spirally wound in one direction.
Here, "helically wound in one direction" means that when viewed from one end of the piezoelectric substrate, it is left-handed (that is, counterclockwise) from the front side to the back side. , the piezoelectric body is spirally wound in a left-handed direction; It means that the piezoelectric body is spirally wound in the right-handed direction.
When the long piezoelectric body is spirally wound in one direction, the phenomenon in which the polarities of the generated charges cancel each other out (that is, the phenomenon in which the piezoelectricity decreases) is suppressed. Therefore, the piezoelectricity of the piezoelectric substrate is further improved.

The embodiment in which a piezoelectric base material is spirally wound in one direction to include a long piezoelectric body includes not only a mode in which only one layer of the piezoelectric body is provided, but also a mode in which multiple layers of the piezoelectric bodies are stacked. be done.
As a mode in which a plurality of layers of the piezoelectric bodies are stacked, for example, the piezoelectric bodies are stacked on the first piezoelectric body spirally wound in one direction, and the second piezoelectric body is spirally wound in the same direction as the one direction. An embodiment in which the wire is wound in a shape is mentioned.

As an aspect of the piezoelectric base material of this embodiment, as an elongated piezoelectric body, a first piezoelectric body spirally wound in one direction and a spirally wound in a direction different from the one direction and a second piezoelectric body, wherein the chirality of the optically active polypeptide contained in the first piezoelectric body and the chirality of the optically active polypeptide contained in the second piezoelectric body are different from each other.

The piezoelectric substance may contain components other than the optically active polypeptide, if necessary.
For example, when the piezoelectric body is an assembly of a plurality of raw yarns, the piezoelectric body may contain an adhesive for fixing the assembly of the plurality of raw yarns. A preferred embodiment of the adhesive will be described later.

<Core material, outer conductor>
The piezoelectric base material of this embodiment includes an elongated core material.
In the piezoelectric base material of the present embodiment, a long piezoelectric body is helically wound around the long core material.

The aspect in which the piezoelectric base material includes a core material that is a conductor has the advantage that an electrical signal (voltage signal or charge signal) can be easily extracted from the piezoelectric body through the core material that is a conductor.
In addition, since this aspect has the same structure as the internal structure (inner conductor and dielectric) provided in the coaxial cable, for example, when the piezoelectric base material of this aspect is applied to the coaxial cable, the electromagnetic shielding property is high, The structure can be resistant to noise.
The conductor is preferably a good electrical conductor, such as copper wire, aluminum wire, SUS wire, metal wire coated with an insulating film, carbon fiber, resin fiber integrated with carbon fiber, tinsel wire, organic conductive wire. materials and the like.
Tinsel wire means a fiber in which copper foil is spirally wound.
Among the conductors, tinsel wire and carbon fiber are preferable from the viewpoint of improving piezoelectric sensitivity and imparting high flexibility.

In particular, it is preferable to use a tinsel wire for applications that require low electrical resistance, bendability, and flexibility.
The form of the tinsel wire has a structure in which a copper foil is spirally wound around a fiber, and the use of copper, which has high electrical conductivity, makes it possible to reduce the output impedance. Therefore, by using the tinsel wire as the core material, the piezoelectricity of the piezoelectric substrate is further improved.

In addition, in processing applications for woven fabrics and knitted fabrics (for example, piezoelectric fabrics, piezoelectric knitted fabrics, piezoelectric sensors (woven piezoelectric sensors, knitted piezoelectric sensors)) that require extremely high flexibility and flexibility, carbon fiber is preferably used.
Moreover, when the piezoelectric base material of the present embodiment is used as a fiber to produce a piezoelectric woven fabric or piezoelectric knitted fabric, suppleness and high flexibility are required. In such applications, filamentous or fibrous signal line conductors are preferred. A piezoelectric base material having filamentous or fibrous signal line conductors has high flexibility, and therefore is suitable for processing with a loom or a knitting machine.

In the case where the piezoelectric substrate includes a conductor core material, the piezoelectric substrate includes an outer conductor on the outer peripheral side of the elongated piezoelectric body spirally wound around the core material, and is a conductor. It is preferable that the core material and the outer conductor are electrically insulated.
In this aspect, the outer conductor can electrostatically shield the inside of the piezoelectric substrate (piezoelectric body and conductive core material). voltage change or charge change is suppressed.
Therefore, more stable piezoelectricity can be obtained in the piezoelectric substrate.
The outer conductor is preferably connected to ground potential.

Although there is no particular limitation on the material of the outer conductor, there are mainly the following materials depending on the cross-sectional shape.
For example, as the material of the outer conductor having a rectangular cross section, a copper foil ribbon obtained by rolling a copper wire having a circular cross section into a flat plate, an Al foil ribbon, or the like can be used.
For example, as the material of the outer conductor having a circular cross section, copper wire, aluminum wire, SUS wire, metal wire coated with an insulating film, carbon fiber, resin fiber integrated with carbon fiber, and tinsel wire can be used.
Also, as the material of the outer conductor, an organic conductive material coated with an insulating material may be used.

It is preferable that the outer conductor is arranged so as to wrap the conductor core material and the piezoelectric body so as not to cause a short circuit with the conductor core material.
As a method of wrapping the core material and the piezoelectric body, which are conductors, select a method of spirally winding a copper foil or the like, or a method of wrapping a copper wire or the like into a cylindrical braid and wrapping it in the braid. can be done.
In addition, the said wrapping method is not limited to these methods.
By wrapping the conductive core material and the piezoelectric body, the electrostatic shielding effect can be further enhanced.
In addition, it is also one of the preferred forms that the external conductor is arranged so as to enclose the minimum basic structural unit (that is, the conductor and the piezoelectric body) of the piezoelectric base material in a cylindrical shape.
Further, for example, when a piezoelectric knitted fabric or a piezoelectric woven fabric, which will be described later, is processed into a sheet by using a piezoelectric base material having the above minimum basic structural unit, a planar or sheet-shaped It is also one of the preferred forms to arrange the conductors in close proximity to each other.

Various cross-sectional shapes such as a circular shape, an elliptical shape, a rectangular shape, and an irregular shape can be applied to the cross-sectional shape of the outer conductor. In particular, since the rectangular cross section can be flatly adhered to a conductor, a piezoelectric body, or the like, it is possible to efficiently detect the charge generated by the piezoelectric effect as a voltage signal.

<Insulator>
(Insulator of first aspect)
The piezoelectric substrate of this embodiment may further comprise the insulator of the first aspect.
The insulator of the first aspect is preferably spirally wound along the outer peripheral surface of the internal conductor.
In this case, the insulator of the first mode may be arranged on the side opposite to the internal conductor when viewed from the piezoelectric body, or may be arranged between the internal conductor and the piezoelectric body.
Moreover, the winding direction of the insulator of the first mode may be the same as or different from the winding direction of the piezoelectric body.
In particular, when the piezoelectric base material includes an outer conductor, the piezoelectric base material further includes the insulator of the first aspect, so that an electrical short circuit occurs between the inner conductor and the outer conductor when the piezoelectric base material bends and deforms. has the advantage of being easier to suppress

The insulator of the first mode is not particularly limited, but for example, vinyl chloride resin, polyethylene resin, polypropylene resin, ethylene/tetrafluoroethylene copolymer (ETFE), tetrafluoroethylene/hexafluoropropylene copolymer Polymer (FEP), tetrafluoroethylene resin (PTFE), tetrafluoroethylene/perfluoropropyl vinyl ether copolymer (PFA), fluororubber, polyester resin, polyimide resin, polyamide resin, polyethylene terephthalate resin (PET), rubber (including elastomer) and the like.
The shape of the insulator of the first mode is preferably an elongated shape from the viewpoint of winding around the conductor.
(Insulator of Second Aspect)
In the piezoelectric base material of the present invention, when the external conductor is provided on the outer circumference, the insulator of the second mode may be provided on the outer circumference of the first outer conductor.
This enables electrostatic shielding and suppresses voltage changes in the conductor (preferably the internal conductor) due to the influence of external static electricity.

The second insulator is not particularly limited, but examples thereof include the materials exemplified as the insulator of the first aspect.
Moreover, the shape of the insulator in the second aspect is not particularly limited as long as it can cover at least a part of the outer conductor.

As a method of providing an insulator on the outermost periphery of the piezoelectric base material of this embodiment, a method of winding a long insulator around the piezoelectric base material before the insulator is provided; a method of winding a cylindrical insulator; A method in which a piezoelectric base material before an insulator is provided is placed in the inner space of (e.g., a heat-shrinkable tube), and then the cylindrical insulator is shrunk and adhered by heat; covered with an insulating molten resin and cooled A method of solidifying; a method of coating and solidifying an insulating resin coating liquid; and the like.

<Adhesive>
The piezoelectric substrate of this embodiment may contain an adhesive.
In a mode in which the piezoelectric substrate contains an adhesive, at least the spirally wound piezoelectric body can be mechanically integrated.
In addition, when the piezoelectric substrate includes a member other than the piezoelectric body such as a core material (core material, external conductor, etc.), the piezoelectric body and the member other than the piezoelectric body can be integrated with an adhesive. .
By mechanically integrating the piezoelectric body (or the piezoelectric body and a member other than the piezoelectric body), when a force is applied to the piezoelectric base material, the force tends to act on the piezoelectric body in the piezoelectric base material. . Therefore, piezoelectricity is further improved.

Adhesive materials include epoxy adhesives, urethane adhesives, vinyl acetate resin emulsion adhesives, (EVA) emulsion adhesives, acrylic resin emulsion adhesives, and styrene-butadiene rubber latex adhesives. Adhesives, silicone resin adhesives, α-olefin (isobutene-maleic anhydride resin) adhesives, vinyl chloride resin solvent adhesives, rubber adhesives, elastic adhesives, chloroprene rubber solvent adhesives, Nitrile rubber-based solvent-based adhesives, cyanoacrylate-based adhesives, and the like are included.

<Other elements>
The piezoelectric base material of this embodiment may include elements other than the elements described above.
Other elements include, for example, fibers other than long piezoelectric bodies.
In the piezoelectric substrate of the present embodiment, fibers other than the long piezoelectric body may be wound together with the long piezoelectric body.
Also, a known extraction electrode can be joined to the piezoelectric base material of the present embodiment. Examples of extraction electrodes include electrode parts such as connectors, crimp terminals, and the like. The electrode component can be joined to the piezoelectric base material by brazing such as soldering, a conductive adhesive, or the like.

Specific examples of the piezoelectric substrate of this embodiment will be described below with reference to the drawings, but the piezoelectric substrate of this embodiment is not limited to the following specific examples.
It should be noted that substantially the same elements are denoted by the same reference numerals throughout the drawings, and redundant description may be omitted. Further, in specific examples of the piezoelectric substrate of the present embodiment, a piezoelectric substrate 50A, a piezoelectric substrate 50B, and a piezoelectric substrate 50C, which will be described later, are examples of the piezoelectric substrate 50 described above.

<Specific example A>
8 is a schematic side view schematically showing a piezoelectric base material according to Specific Example A of the present embodiment, and FIG. 9 is a cross-sectional view taken along the line XX' of FIG.
Specific example A is a specific example of a piezoelectric base material (piezoelectric base material having a core material) of the first embodiment that does not include an external conductor.

As shown in FIG. 8, a piezoelectric base material 50A, which is a specific example A, includes an elongated core member 52 that is a conductor, and an elongated piezoelectric body 54A. The piezoelectric body 54A is spirally wound in one direction along the outer peripheral surface of the core material 52 at a spiral angle β1 from one end to the other end without a gap.
Here, the helix angle β1 is an angle formed by the direction of the helix axis G1 (the axial direction of the core material 52 in this example) and the length direction of the piezoelectric body 54A in a side view.
In this piezoelectric base material 50A, the piezoelectric body 54A is wound counterclockwise around the core material 52. As shown in FIG. Specifically, when the piezoelectric base material 50A is viewed from one end side of the core material 52 in the axial direction (the right end side in FIG. 8), the piezoelectric body 54A is left-handed from the front side of the core material 52 toward the back side. is wound with
Also, in FIG. 8, the main orientation direction of the optically active polypeptide contained in the piezoelectric body 54A is indicated by a double arrow E1. That is, the main orientation direction of the optically active polypeptide and the length direction of the piezoelectric body 54A are substantially parallel.
In the piezoelectric base material 50A, each member (core material 5A and piezoelectric body 54A) is integrated (fixed) by impregnating an adhesive (not shown) between the members.

The effects of the piezoelectric substrate 50A will be described below.
For example, when tension is applied in the longitudinal direction of the piezoelectric substrate 50A, shear stress is applied to the optically active polypeptide contained in the piezoelectric body 54A, and the optically active polypeptide is polarized. The polarization of this optically active polypeptide is considered to occur with the phase aligned in the radial direction of the piezoelectric substrate 50A, as indicated by the arrows in FIG. Thereby, the piezoelectricity of the piezoelectric substrate 50A is exhibited.
Furthermore, since the piezoelectric base material 50A includes the core material 52 that is a conductor, an electrical signal (voltage signal or charge signal) generated in the piezoelectric body 54A can be more easily extracted via the core material 52.

<Specific example B>
FIG. 10 is a schematic side view schematically showing a piezoelectric substrate according to Specific Example B of the present embodiment.
Specific example B is a specific example of the piezoelectric base material (piezoelectric base material having a core material) of the first embodiment that includes an external conductor.

As shown in FIG. 10, the piezoelectric base material 50B of the specific example B has an outer conductor 56 on the outer peripheral side of the piezoelectric body 54A in contrast to the piezoelectric base material 50A of the above-described specific example A, and the core material 52 and the outer conductor 56 are electrically insulated. Other configurations are the same as those of the piezoelectric base material 50A of the specific example A described above.
Preferred aspects of the outer conductor 56 are as described above. The outer conductor 56 is formed, for example, by spirally winding a copper foil ribbon around the piezoelectric body 54A spirally wound around the core 52 .
In the piezoelectric substrate 50B, each member (the core member 52, the piezoelectric body 54A, and the outer conductor 56) is impregnated with an adhesive (not shown) to be integrated (fixed).
As shown in FIG. 10, in the piezoelectric base material 50B, when viewed from the side, the end of the winding body of the piezoelectric body 54A (that is, the spirally wound piezoelectric body 54A) and the end of the outer conductor 56 are separated from each other. Out of position. Thereby, the core material 52 and the outer conductor 56 are reliably insulated. However, the positions of these end portions do not necessarily have to be shifted, and as long as the core material and the outer conductor, which are conductors, are electrically insulated, the positions of these end portions overlap when viewed from the side. There may be.

The piezoelectric base material 50B also has the same effects as the piezoelectric base material 50A.
Furthermore, since the piezoelectric base material 50B includes the outer conductor 56, the inside of the piezoelectric base material 50B (the piezoelectric body 54A and the core material 52, which is a conductor) can be electrostatically shielded by the outer conductor 56. Therefore, it is possible to suppress the voltage change of the core material 52 due to the influence of static electricity outside the piezoelectric base material 50B, and as a result, more stable piezoelectricity can be obtained.

Note that the outer conductor 56 may be omitted from the piezoelectric substrate 50B.
Needless to say, even when the outer conductor 56 is omitted, the effect of the core material 52, which is a conductor, is exhibited.
In addition, even if the outer conductor 56 is omitted, the structure is the same as the inner structure (inner conductor and dielectric) provided in the coaxial cable. It can be a structure that is strong against

<Summary of the first embodiment>
The moving body sheet 20 of the present embodiment includes a supporting body that is provided on the moving body and supports the human body, and a piezoelectric substrate 50 that is provided on the supporting body and detects the pressure received from the human body. The movable body sheet 20 has a long piezoelectric base material 50 provided coaxially around a shaft-shaped inner conductor (core material 52) around the inner conductor (core material 52) and containing an optically active polypeptide. and a piezoelectric body 54A.

The piezoelectric base material 50 can output an electrical signal corresponding to the shear stress in a direction different from the direction in which the pressure is applied by spirally winding the piezoelectric body 54A around the internal conductor (core material 52). be. Therefore, the piezoelectric base material 50 on the line installed on the moving body sheet 20 outputs an electric signal when tension is generated in the axial direction due to the pressure on the moving body sheet 20 . On the other hand, when PVDF is applied to the moving body sheet, an electrical signal is not generated unless the PVDF is applied in the same direction as the pressure applied to the moving body sheet 20 . Therefore, according to the piezoelectric base material 50 of the present embodiment, compared with a piezoelectric body including PVDF that outputs an electric signal upon pressure detection, since an electric signal is outputted upon detection of tension, it can be used as a sheet for a moving body. High sensitivity can be obtained even when installed against an elastic body.
In addition, the piezoelectric body 54A containing an optically active polypeptide that constitutes the piezoelectric substrate 50 can be arranged in a line rather than in a sheet. Compared to piezoelectric bodies, they are superior in that there are fewer restrictions on where they can be placed.

In addition, the piezoelectric body containing PVDF has a large change in output of the amount of electric charge due to temperature change. On the other hand, the piezoelectric substrate 50 of the present embodiment has a smaller change in the output of the charge amount due to temperature changes and a stable output of the charge amount, as compared with the moving body sheet including the piezoelectric body containing PVDF. It is excellent in that it is
On the other hand, a piezoelectric body containing polylactic acid tends to lower its sensor sensitivity when the temperature rises above a predetermined temperature. On the other hand, the piezoelectric substrate 50 of the present embodiment has stable sensor sensitivity even when the temperature is higher than a predetermined temperature, compared with a sheet for a moving object including a piezoelectric body containing polylactic acid. It is excellent in that it is

Therefore, the piezoelectric base material 50 of the present embodiment has excellent sensitivity and is placed on the seat cushion 21 and the seat back 22 of a vehicle in an environment that changes to a high temperature to detect biological information from the human body. suitable for use.

In addition, when a panel is provided and a capacitance-type contact sensor that detects contact with the human body from changes in capacitance caused by the human body in contact with the panel is applied to the seat for a mobile body, the panel in the seat for a mobile body Static electricity is generated in the sensor, which may result in erroneous detection of biometric information.
On the other hand, in the moving body seat 20 of the present embodiment, the piezoelectric base material 50 is arranged inside the elastic body 24 of the seat cushion 21 and the seat back 22, and is not affected by static electricity. It is possible.

In addition, when two films are superimposed with a predetermined gap therebetween, the top film is flexed when touched, and the flexure brings the top film into contact with the bottom film. There is a resistive pressure-sensitive pressure sensor that detects contact with a film by detecting energization from the contact point. When the resistance pressure-sensitive pressure sensor is applied to a seat for a moving body, it is necessary to constantly supply voltage to the pressure sensor and measure the resistance by measuring the flowing current in order to detect the position of the contact point. We need to keep supplying power.
On the other hand, the moving body sheet 20 of the present embodiment detects an electrical signal generated by pressure input to the piezoelectric base material 50, and biometric information can be detected, so power supply is not required.

Therefore, the sheet 20 for a mobile body of the present embodiment can suppress erroneous detection of biometric information due to static electricity and can suppress power consumption, and is therefore suitable for use in detecting biometric information from the human body. .

[Second embodiment]
Next, a moving body seat according to a second embodiment will be described with reference to FIG. 11 . FIG. 11(a) is a plan view of the moving body seat 20 viewed from above in the height direction, and FIG. 11(b) is a front view of the moving body seat 20 viewed from the front in the depth direction. Fig. 3 shows a front view; The present embodiment differs from the first embodiment only in the arrangement of the piezoelectric substrate 50, but the other aspects are the same. In the following description, the same reference numerals are given to the same configurations as in the first embodiment, and overlapping descriptions are omitted.

As an example, as shown in FIG. 11( a ), in the seat cushion 21 , the piezoelectric base material 50 is spirally arranged so as not to overlap the seat cushion 21 . Further, as shown in FIG. 11B, in the seat back 22, the piezoelectric substrates 50 are arranged in a spiral so as not to overlap the seat back 22. As shown in FIG.

By arranging the piezoelectric base material 50 in a spiral shape so as not to overlap the seat cushion 21 and the seat back 22, it is possible to detect biometric information from a wide range on the surface of the seat cushion 21 and the seat back 22. of people can be covered.

[Modification of Second Embodiment]
In the second embodiment, the configuration in which the piezoelectric substrates 50 are spirally arranged on the seat cushion 21 and the seat back 22 has been described. However, it is not limited to this. As an example, as shown in FIG. 12, the piezoelectric substrates 50 may be arranged in a zigzag pattern. Here, FIG. 12(a) shows a plan view of the moving body seat 20 seen from above in the height direction, and FIG. A front view of the seat 20 is shown.

As shown in FIG. 12(a), in the seat cushion 21, the piezoelectric substrates 50 are arranged in a serpentine shape so as not to overlap each other. Further, as shown in FIG. 12(b), in the seat back 22, the piezoelectric substrates 50 are arranged in a zigzag shape so as not to overlap each other.

In the seat cushion 21 and the seat back 22, by arranging the piezoelectric substrates 50 in a zigzag shape so as not to overlap each other, biological information can be collected from a wide range on the surfaces of the seat cushion 21 and the seat back 22, as in the second embodiment. can be detected, and people with various physiques can be covered.

[Third embodiment]
Next, a moving body seat according to a third embodiment will be described with reference to FIG. 13 . 14(a) is a plan view of the moving body seat 20 viewed from above in the height direction, and FIG. 13(b) is a front view of the moving body seat 20 viewed from the front in the depth direction. Fig. 3 shows a front view; It should be noted that this embodiment differs from the second embodiment only in the arrangement of the piezoelectric substrate 50 and the functional configuration, but the other aspects are the same. In the following description, the same reference numerals are given to the same configurations as in the second embodiment, and overlapping descriptions are omitted.

As an example, as shown in FIG. 13( a ), in the seat cushion 21 , a plurality of piezoelectric substrates 50 are arranged independently of each other along the width direction of the seat cushion 21 . Further, as shown in FIG. 13B, in the seat back 22, a plurality of piezoelectric substrates 50 are arranged independently of each other along the width direction of the seat back 22. As shown in FIG.

Next, with reference to FIG. 14, functional configurations of the biological information detection device 10 and the control device 100 when a plurality of piezoelectric substrates 50 are arranged independently of each other will be described. As shown in FIG. 14, the biological information detection device 10 has a detection section 41 and a detection section 42B. Each functional configuration is realized by the CPU 31 reading an execution program stored in the storage 34 and executing it. 14 that are the same as the functions of the biological information detection device 10 and the control device 100 shown in FIG. 7 are given the same reference numerals as in FIG. 7, and description thereof will be omitted.

A detection unit 42B shown in FIG. 14 has a function of detecting biological information such as respiration and pulse from the magnitude and period of the digital signal detected by the detection unit 41 . The detection unit 42B also has a function of detecting position information indicating the position where the passenger is seated by comparing the output signals of the adjacent piezoelectric substrates 50 .

Further, as shown in FIG. 14, the control device 100 has an acquisition unit 111B and a control unit 112B. Each functional configuration is realized by the CPU 101 reading an execution program stored in the storage 104 and executing it.

The acquisition unit 111B has a function of acquiring biometric information and position information from the biometric information detection device 10 .

The control unit 112B has a function of controlling the device 200 using the acquired biological information and position information. For example, the control unit 112B transmits an instruction to execute processing to each device 200 according to the biometric information. Specifically, the control unit 112B detects fluctuations in the intervals between heartbeats from the biological information, and when the fluctuations in the heartbeats become smaller (the intervals between heartbeats are stable), the occupant is sleepy. It determines that there is, and transmits an instruction to brake the actuator as the device 200 . In addition, the control unit 112B detects the size and number of heartbeats from the biological information, and if the size of the heartbeat is greater than the average value for the occupant and the number of heartbeats in a predetermined period is greater than the average value for the occupant, It is determined that the occupant is in a tense state, and an instruction to apply the brake to the actuator as the device 200 is transmitted. In addition, the control unit 112B transmits instructions such as generating an odor to prevent drowsiness and tightening the seatbelt in order to stimulate the five senses of the occupant according to fluctuations in heartbeat intervals based on biological information. Further, the control unit 112B may determine the seating posture of the occupant using the position information, and may transmit an instruction to output audio information regarding the seating posture to the input/output unit 105 such as a speaker, or may output text information. You may transmit the instruction|indication to perform to the display part 106, such as a monitor.

By arranging a plurality of piezoelectric substrates 50 that are independent of each other, the pressure sensed by each piezoelectric substrate 50 is compared to detect the biological information and positional information (seating posture) of the occupant. The device 200 is controlled using the information and location information.

[Modified example of the third embodiment]
3rd Embodiment demonstrated the form by which several piezoelectric base materials 50 are arrange|positioned along the width direction. However, it is not limited to this. As an example, as shown in FIG. 15, a plurality of piezoelectric substrates 50 may be arranged on the seat cushion 21 in the depth direction, and a plurality of piezoelectric substrates 50 may be arranged on the seat back 22 in the height direction.

As shown in FIG. 15( a ), in the seat cushion 21 , a plurality of independent piezoelectric substrates 50 are arranged along the depth direction of the seat cushion 21 . Further, as shown in FIG. 15B, in the seat back 22, a plurality of piezoelectric substrates 50 are arranged independently of each other along the height direction of the seat back 22. As shown in FIG.

By arranging a plurality of piezoelectric substrates 50 independent of each other, the positional information (seating posture) of the occupant can be detected by comparing the pressures independently detected by each of the piezoelectric substrates 50, as in the fourth embodiment. be done.

Here, when a plurality of mutually independent piezoelectric substrates 50 are provided in the seat cushion 21 and the seat back 22, only the piezoelectric substrates 50 in which the piezoelectric body 54A is wound in the right-handed direction may be arranged. Only the piezoelectric substrate 50 with the body 54A wound in the counterclockwise direction may be arranged. In addition, both the piezoelectric base material 50 with the piezoelectric body 54A wound in the right-handed direction and the piezoelectric base material 50 with the piezoelectric body 54A wound in the left-handed direction may be placed alternately between the seat cushion 21 and the seat back. 22 may be placed.

[Fourth Embodiment]
Next, a seat cushion 21 according to a fourth embodiment will be described with reference to FIG. FIG. 16 shows a plan view of the moving body seat 20 viewed from above in the height direction. It should be noted that this embodiment differs from the third embodiment only in the arrangement of the piezoelectric substrate 50, but the other aspects are the same. In the following description, the same reference numerals are given to the same configurations as in the third embodiment, and overlapping descriptions will be omitted.

As an example, as shown in FIG. 16, in the seat cushion 21, a plurality of piezoelectric substrates 50 are arranged so as to cross each other in the width direction and the depth direction. Specifically, three piezoelectric substrates 50 extending in the width direction are arranged at regular intervals in the depth direction. Also, three piezoelectric substrates 50 extending along the depth direction are arranged at equal intervals in the width direction.

By arranging the piezoelectric substrates 50 in the width direction and the depth direction, the relationship between the output of each piezoelectric substrate 50 in the depth direction and the output of each piezoelectric substrate 50 in the width direction results in the occupant's force on the seat cushion 21. Body pressure distribution and the position of the center of gravity of the occupant can be detected. That is, according to the present embodiment, it is possible to detect a more accurate seating posture (positional information) of the occupant.

[Fifth embodiment]
Next, a seat cushion 21 according to a fifth embodiment will be described with reference to FIG. 17 . FIG. 17 shows a plan view of the moving body seat 20 viewed from above in the height direction. Note that this embodiment differs from the fourth embodiment only in the arrangement of the piezoelectric substrate 50, but the other aspects are the same. In the following description, the same reference numerals are given to the same configurations as in the fourth embodiment, and overlapping descriptions will be omitted.

As an example, as shown in FIG. 17, in the seat cushion 21, a plurality of piezoelectric substrates 50 are arranged at a portion where the occupant's thighs are in contact with each other to detect both legs of the occupant. A piezoelectric substrate 50 is arranged on an armrest (not shown).

The seating posture of the occupant, the arrangement of the occupant's arms, and the arrangement of the occupant's legs can be detected by arranging the piezoelectric substrates 50 in accordance with the locations with which the human body is in contact.

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to the following examples as long as the gist of the present invention is not exceeded.

[Example 1]
<Preparation of Optically Active Polypeptide Fiber>
Raw silk was prepared as an optically active polypeptide fiber. Raw silk is a long fiber composed of optically active polypeptides. Raw silk is 21 denier. The thickness of raw silk is 0.06mm-0.04mm.

(Measurement of Orientation Degree F of Optically Active Polypeptide Fiber)
Using a wide-angle X-ray diffractometer ("RINT2550" manufactured by Rigaku Co., Ltd., accessory: rotating sample stage, X-ray source: CuKα, output: 40 kV 370 mA, detector: scintillation counter), raw silk (optically active polypeptide fiber) was fixed to a holder, and the azimuth angle distribution intensity of the crystal face peak [2θ=20°] was measured.
In the obtained azimuth angle distribution curve (X-ray interferogram), the degree of orientation F (degree of c-axis orientation) of raw silk (optically active polypeptide fiber) is calculated from the half width (α) of the peak according to the following formula (a) was calculated.
The orientation degree F of the optically active polypeptide fiber is 0.91.
Orientation (F) = (180°-α)/180° (a)
(α is the half width of the peak derived from the orientation)

<Production of piezoelectric yarn>
A scouring silk was produced by scouring a six-twisted yarn (twisting number: 150 T/m) as a piezoelectric yarn from raw silk by a known method. The orientation degree F of the twisted yarn of this refined silk is 0.86.
Since the orientation degree F of the optically active polypeptide fiber is 0.86 and the six-piece twisted yarn (piezoelectric yarn) was produced using the scouring silk, the length direction of the piezoelectric yarn and the scouring silk ( It can be evaluated that the main orientation direction of the optically active polypeptide contained in the optically active polypeptide fiber) is substantially parallel.

<Production of Piezoelectric Substrate>
As an internal conductor, a tinsel wire "U24-01-00" (wire diameter 0.26 mm, length 200 mm) manufactured by Meisei Sangyo Co., Ltd. was prepared.
The piezoelectric thread was wound counterclockwise on the outer peripheral surface of the internal conductor so as to have a spiral angle of about 45° with as few gaps as possible. As a result, a layer (hereinafter referred to as a "piezoelectric yarn layer") was formed on the outer peripheral surface of the internal conductor, and a piezoelectric substrate precursor was obtained. The piezoelectric thread layer covered the entire outer peripheral surface of the internal conductor. That is, the outer peripheral surface of the inner conductor was not exposed.
"Left-handed" means that the piezoelectric thread is wound counterclockwise from the front side to the back side of the inner conductor (tinshi wire) when viewed from one end in the axial direction of the inner conductor. "Helix angle" refers to the angle formed by the longitudinal direction of the piezoelectric yarn with respect to the axial direction of the inner conductor.
Next, Aron Alpha 902H3 (a cyanoacrylate-based adhesive) manufactured by Toagosei Co., Ltd. was dripped as an adhesive and impregnated to mechanically integrate the raw silk.
Next, a copper foil ribbon slit to a width of 0.3 mm was prepared as an outer conductor. This copper foil ribbon was wound around the core material and tightly wound around the mechanically integrated raw silk so that the raw silk was hardly exposed. Here, the winding direction of the copper foil ribbon was right-handed. Also, the copper foil ribbon was wound so as not to come into contact with the two crimp terminals.
Next, as an insulating coating, a PTFE film having a thickness of 0.15 mm was wound counterclockwise to cover the whole so that the external copper foil was not exposed.
As described above, a piezoelectric substrate was obtained.

<Piezoelectric substrate placed on cushion>
A piezoelectric substrate having a length of 20 cm was prepared, the end of the piezoelectric substrate was connected to the coaxial line, the inner conductor and the outer conductor were arranged so as not to make electrical contact, and the connection part was wrapped with copper foil from the outside. After covering, the copper foil and the external conductor were electrically connected by soldering. Next, as shown in FIG. 4(a), one piezoelectric base material was placed on the urethane cushion of the seat surface and fixed using Kapton tape.

<Detection of Piezoelectric Sensitivity of Piezoelectric Substrate>
Signals from the piezoelectric substrate were detected by the following method.
A coaxial line connected to the end of the piezoelectric substrate was connected to a detection circuit. Here, the wiring on the outer conductor side was connected to the ground side of the detection circuit.
As the detection circuit, an amplifier circuit as shown in FIG. 18 was used, and the variable resistance was adjusted to set the amplification factor to one.
The output voltage (OUTPUT) of this circuit is connected to NI's USB-6002, converted to a digital signal, input to a personal computer via a USB connection, passed through a low-pass filter using the control software LabView on the personal computer, and transferred. After averaging, the voltage signal was measured.
Here, the voltage waveform was measured using a tertiary Butterworth filter with a cutoff frequency of 30 Hz for the low pass.
Using this system, the following method was used to detect biological information while sitting.
FIG. 19 shows voltage fluctuations detected from the piezoelectric substrate.
As shown in FIG. 19, subtle vibrations were detected from the piezoelectric base material placed under the thighs of a seated person, and vibrations due to periodic heartbeats were detected at around 1 second.
In addition, by capturing this voltage signal for several minutes, we were able to detect voltage fluctuations corresponding to body movements due to periodic breathing for several seconds to 10 seconds.

In addition, the following additional remarks are further disclosed regarding one embodiment of the technology disclosed in the present application described above.

(Appendix 1)
The piezoelectric substrate further comprises an insulator spirally wound along the outer peripheral surface of the internal conductor,
the insulator is disposed between the inner conductor and the piezoelectric body;
The sheet for a moving object according to <5>.

1 Control system 2 Vehicle (moving body)
10 biometric information detection device 20 seat for mobile body 21 seat cushion (support)
22 seat back (support)
41 detection parts 42A, 42B detection parts 50, 50A, 50B, 50C piezoelectric substrate 52 core material (inner conductor)
54A Piezoelectric body 56 External conductor 100 Control device

Claims (11)

a support provided on a moving body for supporting a human body;
a piezoelectric substrate provided on the support and detecting pressure received from the human body;
The piezoelectric substrate is
an axial inner conductor;
an elongated piezoelectric body provided coaxially around the inner conductor and containing an optically active polypeptide;
A seat for a moving body. In the piezoelectric substrate, the length direction of the elongated piezoelectric body and the main orientation direction of the optically active polypeptide are substantially parallel.
The seat for a moving object according to claim 1. The orientation degree F of the optically active polypeptide determined by the following formula (a) from X-ray diffraction measurement is 0.50 or more and less than 1.00.
The seat for a moving object according to claim 1 or 2.
Orientation F = (180°-α)/180°... Formula (a)
[In the formula (a), α represents the half width (°) of the orientation-derived peak. ] The elongated piezoelectric body is spirally wound in one direction,
The seat for a moving object according to any one of claims 1 to 3. The piezoelectric substrate further comprises an outer conductor on its perimeter,
The seat for a moving body according to any one of claims 1 to 4. The piezoelectric substrate further comprises an insulator on the outer circumference of the outer conductor,
The seat for a moving object according to claim 5. wherein the optically active polypeptide comprises at least one of silk and spider silk;
The seat for a moving body according to any one of claims 1 to 6. A seat for a moving body according to any one of claims 1 to 7;
a detection unit that detects a signal corresponding to the pressure received by the piezoelectric substrate;
a detection unit that detects biological information in the human body based on the signal detected by the detection unit;
A biological information detection device comprising: the support comprises a plurality of piezoelectric substrates;
The detection unit independently detects a signal from each piezoelectric base material,
The detection unit detects position information indicating a position where the human body is in contact from the signals detected from each piezoelectric base material.
The biological information detecting device according to claim 8. The biological information detection device according to claim 8 or claim 9,
a control device for controlling devices in the moving object based on the information detected by the biological information detection device;
A control system with The control device controls the device according to information related to the heartbeat of the human body obtained from the biological information.
11. Control system according to claim 10.

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