Biosignal acquisition device

Abstract

To provide a biosignal acquisition device that can be miniaturized. [Solution] The biosignal acquisition devices 100, 100a, and 100b, which are mounted on a seat 30, include sensors 10, 10a, 100b, and 100c that detect biosignals of the human body in a seated state, noise reduction members 11 that are positioned between the sensors and the seat and in contact with the sensors and the seat to reduce noise input from the seat to the sensors, and a biosignal calculation unit 22 that calculates biosignals using the biosignals detected by the sensors. When viewed in a seated state, the projection area of ​​the noise reduction member is larger than the projection area of ​​the sensor when viewed in the opposing direction between the contact portion of the human body that is in contact with the seat and the seat. The Young's modulus of the noise reduction member is higher than the Young's modulus of the contact portion on the seat.

Description

Technical Field

[0001] The present disclosure relates to a biological signal acquisition device.

Background Art

[0002] There has been proposed a biological signal acquisition device that includes a sensor such as a piezoelectric sensor provided on a seat cushion of a vehicle or the like and acquires biological signals such as the heartbeat of a person sitting on the seat cushion. Patent Document 1 discloses a configuration in which a depression is provided on a seat surface, a vibration isolator is disposed at the bottom of the depression, a support member is placed on the vibration isolator, and a piezoelectric sensor is further provided thereon. According to such a configuration, a gap is provided between the side surface of the piezoelectric sensor and the side surface of the depression, and the vibration noise is suppressed from being input to the sensor through the seat cushion by the function of the vibration isolator.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, according to the configuration of Patent Document 1, when trying to shift the resonance frequency of the vibration isolator to the low frequency side to remove noise in the frequency band of a biological signal of about 10 to 50 Hz (hertz), it is necessary to configure the vibration isolator with a soft material or increase the mass of the vibration isolator. If the vibration isolator is configured with a soft material, there is a risk that the vibration isolator will be compressed by the force input from the human body and its physical properties will change. Therefore, it is necessary to increase the thickness in the input direction of the vibration. Also, in order to increase the mass of the vibration isolator, an increase in density or an increase in deposition is required. Thus, in the configuration of Patent Document 1, there is a problem that the size of the vibration isolator has to be increased and the biological signal acquisition device becomes larger. Therefore, a biological signal acquisition device that can be miniaturized is desired. [Means for solving the problem]

[0005] As one embodiment of the present disclosure, a biosignal acquisition device (100, 100a, 100b) is provided for use mounted on a seat (30). This biosignal acquisition device includes sensors (10, 10a, 100b, 100c) that detect biosignals of a human body when the human body is seated on the seat; noise reduction members (11) that are positioned between the sensors and the seat and in contact with the sensors and the seat, for reducing noise input from the seat to the sensors; and a bioinformation calculation unit (22) that calculates bioinformation using the biosignals detected by the sensors. When viewed in the opposite direction from the contact portion of the human body that is in contact with the seat and the seat in the seated state, the projection area of ​​the noise reduction member is larger than the projection area of ​​the sensors, and the Young's modulus of the noise reduction member is higher than the Young's modulus of the contact portion on the seat.

[0006] In this type of biosignal acquisition device, when viewed in the opposite direction, the projection area of ​​the noise reduction member is larger than the projection area of ​​the sensor. Therefore, the pressure due to vibration noise input from the part of the sensor in contact with the noise reduction member can be reduced compared to a configuration without a noise reduction member due to the presence of the noise reduction member. As a result, the force corresponding to the vibration noise input to the sensor can be reduced. Furthermore, since the Young's modulus of the noise reduction member is higher than the Young's modulus of the contact part of the seat, when vibration noise is input to the noise reduction member from the seat, or when pressing force from the human body is input to the noise reduction member via the sensor, the part of the noise reduction member other than the part in contact with the sensor will bend, preventing the force from concentrating at the part in contact with the sensor. As a result, the vibration noise reduction effect of the noise reduction member can be improved.

[0007] Another embodiment of the present disclosure is provided, which is a biosignal acquisition device (100c, 100d, 100e) used mounted on a seat. This biosignal acquisition device comprises: sensors (10d to 10f) positioned in contact with the seat (30) and detecting biosignals of a person when the person is seated on the seat; a noise reduction member (11d) positioned in contact with the seat and in contact with at least a portion of the side surface (Ss) of the sensor, which is a side surface that intersects with the contact surface (S1) of the sensor that comes into contact with the person in the seated state, for reducing noise input from the seat to the sensor; and a biosignal calculation unit (22) that calculates the biosignals using the biosignals detected by the sensor. The Young's modulus of the noise reduction member is higher than the Young's modulus of the portion of the seat including the contact surface.

[0008] This type of biosignal acquisition device includes a noise reduction member positioned in contact with the seat, and in contact with at least a portion of the side surface of the sensor that intersects with the contact surface of the sensor that comes into contact with the human body when seated. This noise reduction member reduces the noise input from the seat to the sensor, thus reducing the pressure caused by vibration noise input from the seat to the sensor compared to a configuration without a noise reduction member. As a result, the force corresponding to the vibration noise input to the sensor can be reduced. Furthermore, since the Young's modulus of the noise reduction member is higher than the Young's modulus of the contact portion of the seat, when vibration noise is input to the noise reduction member from the seat, or when pressing force from the human body is input to the noise reduction member, the noise reduction member will not bend, preventing the concentration of force on the sensor. As a result, the vibration noise reduction effect of the noise reduction member can be improved. [Brief explanation of the drawing]

[0009] [Figure 1] This is an explanatory diagram showing the schematic configuration of a biosignal acquisition device as one embodiment of the present disclosure. [Figure 2] This is a perspective view showing the external configuration of the sensor and noise reduction member in the first embodiment. [Figure 3] This is an explanatory diagram showing the relationship between the diameter of the noise reduction component and the pressure and noise amplitude. [Figure 4] This is a block diagram showing the schematic configuration of the biosignal acquisition device in the second embodiment. [Figure 5] This is a block diagram showing the schematic configuration of the biosignal acquisition device in the third embodiment. [Figure 6] This is a block diagram showing the schematic configuration of the biosignal acquisition device in the fourth embodiment. [Figure 7] This is a block diagram showing the schematic configuration of the biosignal acquisition device in the fifth embodiment. [Figure 8] This is a block diagram showing the schematic configuration of the biosignal acquisition device in the sixth embodiment. [Modes for carrying out the invention]

[0010] A. First Embodiment: The biosignal acquisition device 100 shown in Figure 1 is mounted on a seat 30. The biosignal acquisition device 100 acquires biosignals from the human body HB of a person HM seated on the seat 30. In this embodiment, the biosignal acquired by the biosignal acquisition device 100 is the cardiac pulsation of the person HM's heart HH. In addition to cardiac pulsation, any signal indicating vibrations generated by the person HM, such as respiration, pulse, heart sounds, organ movement, fetal movement, or body movement, may be acquired. The biosignal acquisition device 100 is configured to acquire biosignals regardless of whether the person HM is wearing clothing at the time of measurement.

[0011] In this embodiment, the seat 30 is configured as a seat for a vehicle. The seat 30 is made of a material that combines softness and resilience, such as polyurethane, and has a relatively low Young's modulus. Instead of a vehicle seat, it may be configured as a seat for any moving object such as a train or ship, or as a seat fixedly or movably positioned on any floor indoors or outdoors. The phrase "used mounted on the seat 30" has a broad meaning and is not limited to all components of the biosignal acquisition device 100 being mounted on the seat 30, but also includes cases where only a part of the biosignal acquisition device 100 is mounted on the seat 30.

[0012] Figure 1 shows the X, Y, and Z axes, which are orthogonal to each other. The X axis is parallel to the width direction of the seat 30. The Z axis is parallel to the surface Sa where the human body HB of the person HM is in contact with the front surface 31 of the seat 30 when the person HM is seated on the seat 30 (hereinafter referred to as the "seated state"), and is orthogonal to the X axis. The Z axis is parallel to the direction approximating the vertical direction. The Y axis is parallel to the opposing direction. The "opposing direction" means the direction in which the contact portion of the human body HB that is in contact with the seat 30, i.e., the back, faces the seat 30 when the person is seated. In this embodiment, the Y axis is parallel to the direction approximating the horizontal direction. Note that the XYZ axes in other figures correspond to the XYZ axes in Figure 1. In this embodiment, the +X direction and the -X direction are sometimes collectively referred to as the "X-axis direction". Similarly, the +Y and -Y directions are sometimes collectively referred to as the "Y-axis direction," and the +Z and -Z directions are sometimes collectively referred to as the "Z-axis direction."

[0013] The biosignal acquisition device 100 comprises a sensor 10, a noise reduction member 11, and a computer 20.

[0014] Sensor 10 contacts the human body HB in a seated position to detect cardiac movement, which is a biological signal. In this embodiment, sensor 10 is configured as a piezoelectric sensor. As shown in Figure 2, in this embodiment, sensor 10 has a thin cylindrical external shape. In this embodiment, the diameter r1 of sensor 10 is 10 mm (millimeters). The thickness h1 of sensor 10 is 1 mm. As shown in Figure 1, in a seated position, sensor 10 contacts the human body HB of person HM, specifically the back. The thickness direction of sensor 10 is parallel to the Y-axis direction. Sensor 10 is positioned such that both the end face S1 in the +Y direction and the end face S2 in the -Y direction are parallel to surface Sa.

[0015] The noise reduction member 11 is positioned between the sensor 10 and the seat 30, in contact with both the sensor 10 and the seat 30. The noise reduction member 11 is a member for reducing noise input from the seat 30 to the sensor 10. "Noise input from the seat 30 to the sensor 10" refers to vibrations during vehicle operation, such as road noise and vibration noise associated with engine rotation. As shown in Figure 2, the noise reduction member 11 has a thin, disc-shaped external form. The diameter r2 of the noise reduction member 11 is 40 mm. The thickness h2 of the noise reduction member 11 is 0.5 mm. As shown in Figure 2, the noise reduction member 11 is positioned such that its +Y direction end face S11 and -Y direction end face S12 are both parallel to surface Sa. End face S11 of the noise reduction member 11 is in contact with the end face S2 of the sensor 10. End face S12 of the noise reduction member 11 is in contact with the front surface 31 of the seat 30, as shown in Figure 1. In this embodiment, the sensor 10 and the noise reduction member 11 are arranged in contact with each other such that their respective centers overlap in the Y-axis direction. In this embodiment, the sensor 10 is bonded to the noise reduction member 11 with an adhesive. The noise reduction member 11 is made of a material with a Young's modulus higher than that of the seat 30. Specifically, in this embodiment, the noise reduction member 11 is made of brass. However, instead of brass, it may be made of any material with a Young's modulus higher than polyurethane. For example, the noise reduction member 11 may be made of a material having a hardness of 100 MPa (megapascals) or more.

[0016] As shown in FIG. 1, computer 20 includes a CPU (Central Processing Unit) 21 and a memory 23. Computer 20 may be configured as, for example, a microcomputer. By executing a program stored in memory 23, CPU 21 functions as a biological information calculation unit 22. Biological information calculation unit 22 obtains biological information using the biological signal detected by sensor 10. Specifically, biological information calculation unit 22 obtains biological information such as heart rate and heart rate interval using the heart beat detected by sensor 10. Computer 20 is electrically connected to sensor 10 via communication line 13. Computer 20 receives the biological signal detected by sensor 10.

[0017] As shown in FIG. 2 and as described above, in the facing direction, that is, when viewed in the Y-axis direction, the projected area of noise reduction member 11 is larger than the projected area of sensor 10. Therefore, in the seated state shown in FIG. 1, the pressure of the vibration noise input from seat cushion 30 to sensor 10 via noise reduction member 11 is reduced compared to a configuration in which sensor 10 is directly disposed on the front surface 31 of seat cushion 30 without noise reduction member 11 (hereinafter referred to as "comparative example configuration"). Since the area of the end face S2 of sensor 10 is the same in the present embodiment and the comparative example configuration, the force corresponding to the vibration noise input from seat cushion 30 to sensor 10 can be reduced in the configuration of the present embodiment compared to the comparative configuration. Further, the Young's modulus of noise reduction member 11 is higher than the Young's modulus of the contact portion of seat cushion 30 where noise reduction member 11 contacts. Therefore, when the pressing force from human body HB is input to noise reduction member 11 via sensor 10, in noise reduction member 11, portions other than the portion contacting sensor 10 are bent, and it is possible to suppress the concentration of force (reaction force of the pressing force or force of vibration noise) on the portion of noise reduction member 11 that contacts sensor 10. Thereby, the effect of reducing vibration noise by noise reduction member 11 can be improved.

[0018] Note that the "projected areas of the noise reduction member 11 and the sensor 10" described above refer to the projected areas of the noise reduction member 11 and the sensor 10 on the X-Z plane, which is a plane having a perpendicular line parallel to the Y-axis direction, or in other words, a plane orthogonal to the facing direction.

[0019] In FIG. 3, the horizontal axis represents the pressure (kPa) on the end face S2 of the sensor 10, and the vertical axis represents the amplitude (arbitrary unit) of the noise input to the sensor 10. As shown in FIG. 3, the magnitude (amplitude) of the noise input to the sensor 10 can vary depending on the size of the diameter r2 of the noise reduction member 11. Specifically, in FIG. 3, in the configuration without the noise reduction member 11 (comparative example configuration), the pressure on the end face S2 of the sensor 10 is relatively high, and a point p1 with a relatively large noise amplitude is obtained. In contrast, point p2 with a diameter r2 of 20 mm, point p3 with a diameter r2 of 27 mm, and point p4 with a diameter r2 of 41 mm have gradually reduced pressure and noise amplitude in this order. For example, the pressure at point p4 is 1 / 3 or less of the pressure at point p1, and the noise amplitude at point p4 is reduced to about 2 / 3 of the noise amplitude at point p1. Thus, in the biological signal acquisition device 100 of the present embodiment, by making the diameter r2 larger (4 times) than the diameter r1, the noise amplitude can be significantly reduced compared to the comparative example configuration. Therefore, the diameter r2 may be any size within the range shown by the following formula (1), for example. 1×r1 < r2 < 5×r1 ···(1)

[0020] Also, the diameter r2 may preferably be any size within the range shown by the following formula (2). 1.5×r1 < r2 < 4.5×r1 ···(2)

[0021] Also, the diameter r2 may more preferably be any size within the range shown by the following formula (3). 2×r1 < r2 < 4×r1 ···(3)

[0022] According to the first embodiment of the biosignal acquisition device 100 described above, when viewed in the opposing direction (Y-axis direction), the projection area of ​​the noise reduction member 11 is larger than the projection area of ​​the sensor 10. Therefore, the pressure due to vibration noise input from the end face S2 in contact with the noise reduction member 11 at the sensor 10 can be reduced by the presence of the noise reduction member 11 compared to the comparative example configuration without the noise reduction member 11. As a result, the force corresponding to the vibration noise input to the sensor 10 can be reduced. Furthermore, since the Young's modulus of the noise reduction member 11 is higher than the Young's modulus of the contact portion at the seat 30, when vibration noise is input to the noise reduction member 11 from the seat 30, or when pressing force from the human body HB is input to the noise reduction member 11 via the sensor 10, the part of the noise reduction member 11 other than the part in contact with the sensor 10 will bend, preventing the force from concentrating at the part in contact with the sensor 10. As a result, the vibration noise reduction effect of the noise reduction member 11 can be improved.

[0023] B. Second Embodiment: The biosignal acquisition device 100a of the second embodiment shown in Figure 4 differs from the biosignal acquisition device 100 of the first embodiment shown in Figure 1 in that it is equipped with a plurality of sensors 10a and 10b. The other components of the biosignal acquisition device 100a of the second embodiment are the same as those of the biosignal acquisition device 100, so the same components are denoted by the same reference numerals and their detailed descriptions are omitted.

[0024] Sensors 10a and 10b both have the same configuration as sensor 10 in the first embodiment. Sensor 10a is positioned in contact with the noise reduction member 11, similar to sensor 10 in the first embodiment. On the other hand, sensor 10b is not in contact with the noise reduction member 11, but is positioned in direct contact with the front surface 31 of the seat 30. Sensors 10a and the noise reduction member 11 have the same configuration as sensor 10 and noise reduction member 11 in the first embodiment. In this embodiment, for the sake of explanation, sensor 10a will be referred to as the first sensor 10a, and sensor 10b will be referred to as the second sensor 10b. Both the first sensor 10a and the second sensor 10b are connected to the computer 20 by a communication line 13.

[0025] As shown in Figure 4, the first sensor 10a is positioned in contact with the front surface 31 of the seat 30 via a noise reduction member 11. On the other hand, the second sensor 10b is positioned in direct contact with the front surface 31 of the seat 30 without the noise reduction member 11. Therefore, the end face (end face S1) of the first sensor 10a in the +Y direction is located further in the +Y direction than the end face (end face S1) of the second sensor 10b in the +Y direction. Consequently, in the seated position, the first sensor 10a is pressed more strongly against the human body HB than the second sensor 10b. Therefore, in the seated position, the amplitude of the biosignal input to the first sensor 10a is greater than the amplitude of the biosignal input to the second sensor 10b.

[0026] On the other hand, since the first sensor 10a is positioned in contact with the noise reduction member 11, similar to the sensor 10 of the first embodiment, the pressure at the end face S2 in the -Y direction is smaller than the pressure at the end face S2 of the second sensor 10b in the -Y direction. Therefore, the vibration noise input to the first sensor 10a from the seat 30 is reduced compared to the vibration noise input to the second sensor 10b.

[0027] In this embodiment, the bio-information calculation unit 22 uses the difference signal between a signal containing a bio-signal detected by the first sensor 10a and a signal containing a bio-signal detected by the second sensor 10b to determine the heart rate and heart rate interval, which are bio-information. "Signal containing a bio-signal" means a signal that includes a signal indicating cardiac movement and a signal indicating vibration noise input from the seat 30. Specifically, the bio-information calculation unit 22 uses the difference signal (ΔS) between the cardiac movement signal detected by the first sensor 10a and the cardiac movement signal detected by the second sensor 10b, and the difference signal (ΔN) between the vibration noise signal detected by the first sensor 10a and the vibration noise signal detected by the second sensor 10b to determine the heart rate, etc.

[0028] As described above, the amplitude of the biological signal input to the first sensor 10a is greater than the amplitude of the biological signal input to the second sensor 10b. On the other hand, the vibration noise input to the first sensor 10a is reduced compared to the vibration noise input to the second sensor 10b. Assuming that the relationship between the biological signal (S) and vibration noise (N) input to the two sensors 10a and 10b is clear, the ratio of ΔS to ΔN (S / N ratio) is higher than the ratio of the biological signal (S) detected by the first sensor 10a to the vibration noise (N) (S / N ratio). For example, if the S / N ratio at the first sensor 10a is 10:5 and the S / N ratio at the second sensor 10b is 1:2, then ΔS:ΔN = 9:3, which is higher than 10:5.

[0029] The biosignal acquisition device 100a of the second embodiment described above has the same effects as the biosignal acquisition device 100 of the first embodiment. In addition, since biological information is obtained using the difference signal between the signal including the biological signal detected by the first sensor 10a, which is positioned in contact with the noise reduction member 11, and the signal including the biological signal detected by the second sensor 10b, which is not in contact with the noise reduction member 11 but is positioned in contact with the seat 30, biological information can be obtained based on a signal with an improved S / N ratio, and biological information can be obtained with high accuracy.

[0030] C. Third Embodiment: The biosignal acquisition device 100b of the third embodiment shown in Figure 5 differs from the biosignal acquisition device 100 of the first embodiment shown in Figure 1 in that it is equipped with a plurality of sensors 10a and 10c. The other components of the biosignal acquisition device 100b of the third embodiment are the same as those of the biosignal acquisition device 100, so the same components are denoted by the same reference numerals and their detailed descriptions are omitted.

[0031] Sensors 10a and 10b both have the same configuration as sensor 10 in the first embodiment. Sensor 10a is the same as the first sensor 10a in the second embodiment. That is, sensor 10a is positioned in contact with the noise reduction member 11. Sensor 10c is not in contact with the noise reduction member 11 and is positioned inside the seat 30. In this embodiment, for the sake of explanation, sensor 10a is referred to as the first sensor 10a and sensor 10c is referred to as the third sensor 10c. Both the first sensor 10a and the third sensor 10c are connected to the computer 20 by a communication line 13.

[0032] As shown in Figure 5, the first sensor 10a is positioned in contact with the front surface 31 of the seat 30 via a noise reduction member 11. On the other hand, the third sensor 10c is positioned in direct contact with the seat 30 without the noise reduction member 11. In the seated position, the third sensor 10c is not in contact with the human body HB. Therefore, the amplitude of the biosignal input to the third sensor 10c is smaller than the amplitude of the biosignal input to the first sensor 10a, which is in direct contact with the human body HB.

[0033] On the other hand, since the first sensor 10a is positioned in contact with the noise reduction member 11, similar to the sensor 10 of the first embodiment, the pressure at the end face S2 in the -Y direction is smaller than the pressure at the end face S2 of the third sensor 10c in the -Y direction. Therefore, the vibration noise input to the first sensor 10a from the seat 30 is reduced compared to the vibration noise input to the third sensor 10c.

[0034] In this embodiment, the biological information calculation unit 22, similar to the biological information calculation unit 22 of the second embodiment described above, uses the difference signal between the signal containing the biological signal detected by the first sensor 10a and the signal containing the biological signal detected by the third sensor 10c to determine the biological information, namely the heart rate and heart rate interval. Therefore, the biological signal acquisition device 100b of the third embodiment can improve the signal-to-noise ratio between the biological signal and vibration noise, similar to the biological signal acquisition device 100a of the second embodiment.

[0035] The biosignal acquisition device 100b of the third embodiment described above has the same effects as the biosignal acquisition device 100 of the first embodiment. In addition, since biological information is obtained using the difference signal between the signal including the biological signal detected by the first sensor 10a, which is positioned in contact with the noise reduction member 11, and the signal including the biological signal detected by the third sensor 10c, which is not in contact with the noise reduction member 11 but is positioned inside the seat 30, biological information can be obtained based on a signal with an improved S / N ratio, and biological information can be obtained with high accuracy.

[0036] D. Fourth Embodiment: The biosignal acquisition device 100c of the fourth embodiment shown in Figure 6 differs from the biosignal acquisition device 100 of the first embodiment shown in Figure 1 in that it is equipped with a sensor 10d instead of a sensor 10, and with a noise reduction member 11d instead of a noise reduction member 11. The other components of the biosignal acquisition device 100c of the fourth embodiment are the same as those of the biosignal acquisition device 100, so the same components are denoted by the same reference numerals, and their detailed descriptions are omitted.

[0037] The relative position of the sensor 10d to the noise reduction member 11d differs from that of the sensor 10 in the first embodiment. The configuration of the sensor 10d itself, including its size, is the same as that of the sensor 10 in the first embodiment. A portion of the sensor 10d in the thickness direction (Y-axis direction) is surrounded by the noise reduction member 11d, with its side surface Ss in contact with it around its entire circumference. That is, the sensor 10d has a configuration in which a first portion 18 surrounded by the noise reduction member 11d and a second portion 19 exposed from the noise reduction member 11d are connected in the Y-axis direction. In other words, the noise reduction member 11d is positioned to surround a portion of the sensor 10d's side surface Ss in the thickness direction around its entire circumference. A through-hole for housing the sensor 10d is provided in the center of the noise reduction member 11d, and a portion of the sensor 10d on the -Y direction side is housed in this through-hole. The -Y end face S2 of the sensor 10d and the -Y end face S12 of the noise reduction member 11d lie on the same plane and are both positioned in contact with the front surface 31 of the seat 30. The side surface Ss can be said to be the surface that intersects with the end face S1 which will be in contact with the human body HB.

[0038] With this configuration, the pressure at the end face S2 of the sensor 10d is reduced compared to the comparative example configuration without the noise reduction member 11d. Therefore, the amplitude of the vibration noise input from the end face S2 of the sensor 10d can be reduced, as in the first embodiment.

[0039] The biosignal acquisition device 100c of the fourth embodiment described above is positioned in contact with the seat 30 and is positioned in contact with a part of the thickness direction of the side surface Ss of the sensor 10d, which is the surface that intersects with the contact surface (end surface S1) of the sensor 10d that contacts the human body HB when seated. The device is equipped with a noise reduction member 11d for reducing noise input from the seat 30 to the sensor 10d. Therefore, compared to the comparative example configuration without the noise reduction member 11d, the pressure due to vibration noise input from the seat 30 to the sensor 10d can be reduced. As a result, the force corresponding to the vibration noise input to the sensor 10d can be reduced. Furthermore, since the Young's modulus of the noise reduction member 11d is higher than the Young's modulus of the contact portion on the seat 30, when vibration noise is input to the noise reduction member 11d from the seat 30, or when pressing force from the human body HB is input to the noise reduction member 11d, the noise reduction member 11d will bend, which can suppress the concentration of force on the sensor 10d. Therefore, the vibration noise reduction effect of the noise reduction member 11d can be improved.

[0040] Furthermore, since the noise reduction member 11d is positioned to surround a portion of the sensor 10d's side surface Ss in the thickness direction over its entire circumference, it can reduce pressure due to vibration noise more effectively than a configuration in which the noise reduction member 11d surrounds only a portion of the sensor 10d's entire circumference over a portion of the sensor 10d's side surface Ss in the thickness direction.

[0041] E. Fifth Embodiment: The fifth embodiment of the biosignal acquisition device 100d shown in Figure 7 differs from the fourth embodiment of the biosignal acquisition device 100c shown in Figure 6 in that it is equipped with a plurality of sensors 10d and 10e. The other components of the fifth embodiment of the biosignal acquisition device 100d are the same as those of the biosignal acquisition device 100c, so the same components are denoted by the same reference numerals, and their detailed descriptions are omitted.

[0042] Sensor 10d and sensor 10e both have the same configuration as sensor 10d in the fourth embodiment. Sensor 10d is positioned in contact with the noise reduction member 11d, similar to sensor 10d in the fourth embodiment. On the other hand, sensor 10e is not in contact with the noise reduction member 11d, but is positioned in direct contact with the front surface 31 of the seat 30. Sensor 10d and noise reduction member 11d have the same configuration as sensor 10d and noise reduction member 11d in the fourth embodiment. In this embodiment, for the sake of explanation, sensor 10d will be referred to as the first sensor 10d, and sensor 10e will be referred to as the second sensor 10e. Both the first sensor 10d and the second sensor 10e are connected to the computer 20 by a communication line 13.

[0043] As shown in Figure 7, the first sensor 10d is positioned in contact with the front surface 31 via a noise reduction member 11d. On the other hand, the second sensor 10e is positioned in direct contact with the front surface 31 without the noise reduction member 11d. Therefore, the end face (end face S1) of the first sensor 10d in the +Y direction is located further in the +Y direction than the end face (end face S1) of the second sensor 10e in the +Y direction. Consequently, in the seated position, the first sensor 10d is pressed more firmly against the human body HB than the second sensor 10e. Therefore, in the seated position, the amplitude of the biosignal input to the first sensor 10d is greater than the amplitude of the biosignal input to the second sensor 10e.

[0044] On the other hand, since the first sensor 10d is positioned in contact with the noise reduction member 11d, similar to the sensor 10d in the fourth embodiment, the pressure at the end face S2 in the -Y direction is smaller than the pressure at the end face S2 of the second sensor 10e in the -Y direction. For this reason, the vibration noise input to the first sensor 10d from the seat 30 is reduced compared to the vibration noise input to the second sensor 10e.

[0045] In the fifth embodiment, the biological information calculation unit 22, similar to the second embodiment, uses the difference signal between the signal containing the biological signal detected by the first sensor 10d and the signal containing the biological signal detected by the second sensor 10e to determine the heart rate and heart rate interval, which are biological information. Therefore, the biological signal acquisition device 100d of the fifth embodiment can improve the signal-to-noise ratio between the biological signal and vibration noise, similar to the biological signal acquisition device 100a of the second embodiment.

[0046] The biosignal acquisition device 100d of the fifth embodiment described above has the same effects as the biosignal acquisition device 100c of the fourth embodiment. In addition, since biological information is obtained using the difference signal between the signal including the biological signal detected by the first sensor 10d which is positioned in contact with the noise reduction member 11d and the signal including the biological signal detected by the second sensor 10e which is not in contact with the noise reduction member 11d but is positioned in contact with the seat 30, biological information can be obtained based on a signal with an improved S / N ratio, and biological information can be obtained with high accuracy.

[0047] F. Sixth Embodiment: The biosignal acquisition device 100e of the sixth embodiment shown in Figure 8 differs from the biosignal acquisition device 100c of the fourth embodiment shown in Figure 6 in that it is equipped with a plurality of sensors 10d and 10f. The other components of the biosignal acquisition device 100e of the sixth embodiment are the same as those of the biosignal acquisition device 100c, so the same components are denoted by the same reference numerals, and their detailed descriptions are omitted.

[0048] Sensor 10d and sensor 10f both have the same configuration as sensor 10d in the fourth embodiment. Sensor 10d is the same as the first sensor 10d in the fifth embodiment. That is, sensor 10d is positioned in contact with the noise reduction member 11d. Sensor 10f is not in contact with the noise reduction member 11d and is positioned inside the seat 30. In this embodiment, for the sake of explanation, sensor 10d is referred to as the first sensor 10d and sensor 10f is referred to as the third sensor 10f. Both the first sensor 10d and the third sensor 10f are connected to the computer 20 by a communication line 13.

[0049] As shown in Figure 8, the first sensor 10d is positioned in contact with the front surface 31 of the seat 30 via a noise reduction member 11d. On the other hand, the third sensor 10f is positioned in direct contact with the seat 30 without the noise reduction member 11d. In the seated position, the third sensor 10f is not in contact with the human body HB. Therefore, the amplitude of the biosignal input to the third sensor 10f is smaller than the amplitude of the biosignal input to the first sensor 10d, which is in direct contact with the human body HB.

[0050] On the other hand, since the first sensor 10d is positioned in contact with the noise reduction member 11d, similar to the sensor 10d in the fourth embodiment, the pressure at the end face S2 in the -Y direction is smaller than the pressure at the end face S2 of the third sensor 10f in the -Y direction. For this reason, the vibration noise input to the first sensor 10d from the seat 30 is reduced compared to the vibration noise input to the third sensor 10f.

[0051] In this embodiment, the biological information calculation unit 22, similar to the biological information calculation unit 22 of the fifth embodiment described above, uses the difference signal between the signal containing the biological signal detected by the first sensor 10d and the signal containing the biological signal detected by the third sensor 10f to determine the heart rate and heart rate interval, which are biological information. Therefore, the biological signal acquisition device 100e of the sixth embodiment can improve the signal-to-noise ratio between the biological signal and vibration noise, similar to the biological signal acquisition device 100d of the fifth embodiment.

[0052] The biosignal acquisition device 100e of the sixth embodiment described above has the same effects as the biosignal acquisition device 100c of the fourth embodiment. In addition, since biological information is obtained using the difference signal between the signal including the biological signal detected by the first sensor 10d which is placed in contact with the noise reduction member 11d and the signal including the biological signal detected by the third sensor 10f which is not in contact with the noise reduction member 11d but is placed inside the seat 30, biological information can be obtained based on a signal with an improved S / N ratio, and biological information can be obtained with high accuracy.

[0053] G. Other embodiments: (G1) The specific dimensions of the sensors 10, 10a to 10f and the noise reduction members 11 and 11d in each embodiment are not limited to the values ​​specifically described in each embodiment. For example, the diameter r1 of the sensors 10, 10a to 10f is not limited to 10 mm, but may be any value smaller than the diameter r2, within the range of 0.1 mm to 500 mm. Also, the thickness h1 of the sensors 10, 10a to 10f may be any value within the range of 0.1 mm to 100 mm. Also, the diameter r2 of the noise reduction members 11 and 11d may be any value larger than the diameter r1.

[0054] (G2) The specific shapes of the sensors 10, 10a to 10f and the noise reduction members 11 and 11d in each embodiment are not limited to the shapes specifically described in each embodiment. For example, the sensors 10, 10a to 10f may be rectangular prisms instead of cylindrical. Similarly, the noise reduction members 11 and 11d may have a thin rectangular plate-like appearance instead of a disc shape.

[0055] (G3) In the fourth to sixth embodiments, the noise reduction member 11d was arranged to surround a portion of the side surface Ss of the sensors 10d to 10f over the entire circumference of the sensor 10d, but the disclosure is not limited thereto. The noise reduction member 11d may be arranged to surround (contact) only a portion of the side surface Ss of the sensors 10d to 10f over the entire circumference of the sensor 10d. In such a configuration as well, the pressure at the end face S2 in the -Y direction of the sensors 10d to 10f can be reduced by the presence of the noise reduction member 11d.

[0056] (G4) In the fourth to sixth embodiments, when viewed in the opposing direction (Y-axis direction), the projection area of ​​the noise reduction member 11d may be less than or equal to the projection area of ​​the sensor 10d. In this configuration as well, by positioning the noise reduction member 11d in contact with a part of the side surface Ss of the sensor 10d and at least a part of its entire circumference, the pressure on the end face S2 of the sensor 10d can be reduced, thereby reducing the amplitude of vibration noise input to the sensor 10d.

[0057] (G5) The biosignal acquisition devices 100, 100a to 100e in each embodiment are merely examples and can be modified in various ways. For example, in the second, third, fifth, and sixth embodiments, there were two sensors, but there may be any number of sensors, three or more. Also, instead of placing the sensors 10, 10a to 10f on the front surface 31 or inside the seat 30, or in addition to placing them on the front surface 31 or inside the seat 30, they may be placed on the surface of the seat or inside the seat.

[0058] (G6) The biometric information calculation unit 22 and its methods described herein may be implemented by a dedicated computer provided by configuring a processor and memory programmed to perform one or more functions embodied by a computer program. Alternatively, the biometric information calculation unit 22 and its methods described herein may be implemented by a dedicated computer provided by configuring a processor by one or more dedicated hardware logic circuits. Alternatively, the biometric information calculation unit 22 and its methods described herein may be implemented by one or more dedicated computers configured by a combination of a processor and memory programmed to perform one or more functions and a processor configured by one or more hardware logic circuits. Furthermore, the computer program may be stored as instructions executed by the computer on a computer-readable non-transitional tangible recording medium.

[0059] This disclosure is not limited to the embodiments described above, and can be implemented in various configurations without departing from its spirit. For example, the technical features in each embodiment corresponding to the technical features in the embodiments described in the summary of the invention can be replaced or combined as appropriate in order to solve some or all of the above-mentioned problems, or to achieve some or all of the above-mentioned effects. Furthermore, if a technical feature is not described as essential in this specification, it can be deleted as appropriate. For example, this disclosure may be implemented in the following forms.

[0060] [Form 1] A biosignal acquisition device (100, 100a, 100b) used mounted on a seat (30), In the seated position with a human body seated on the aforementioned seat, sensors (10, 10a, 100b, 100c) for detecting the human body's biological signals, A noise reduction member (11) is positioned between the sensor and the seat, in contact with the sensor and the seat, to reduce noise input from the seat to the sensor. A biological information calculation unit (22) that uses the biological signal detected by the sensor to obtain biological information, Equipped with, When viewed in the seated position, with respect to the contact portion of the human body that is in contact with the seat and the seat facing each other, the projection area of ​​the noise reduction member is larger than the projection area of ​​the sensor. The Young's modulus of the noise reduction member is higher than the Young's modulus of the contact portion in the seat. A device for acquiring biological signals. [Form 2] In the biosignal acquisition device described in Embodiment 1, The system includes multiple sensors (10a, 10b), The plurality of sensors include a first sensor (10a) positioned in contact with the noise reduction member, and a second sensor (10b) that is not in contact with the noise reduction member but is positioned in contact with the seat. The biological information calculation unit is a biological signal acquisition device that obtains the biological information using the difference signal between a signal including the biological signal detected by the first sensor and a signal including the biological signal detected by the second sensor. [Form 3] In the biosignal acquisition device described in Embodiment 1 or Embodiment 2, The system includes multiple sensors (10a, 10c), The plurality of sensors include a first sensor (10a) positioned in contact with the noise reduction member, and a third sensor (10c) that is not in contact with the noise reduction member and is positioned inside the seat. The biological information calculation unit is a biological signal acquisition device that obtains the biological information using the difference signal between the signal containing the biological signal detected by the first sensor and the signal containing the biological signal detected by the third sensor. [Form 4] A biosignal acquisition device (100c, 100d, 100e) that is mounted on a seat, A sensor (10d~10f) is positioned in contact with the seat (30) and detects the biological signals of the human body when the human body is seated on the seat. A noise reduction member (11d) is positioned in contact with the seat and is positioned in contact with a portion of the thickness direction of the sensor, which is a side surface (Ss) of the sensor that intersects with the contact surface (S1) of the sensor that comes into contact with the human body in the seated position, for reducing noise input to the sensor from the seat. A biological information calculation unit (22) that uses the biological signal detected by the sensor to obtain the biological information, Equipped with, The Young's modulus of the noise reduction member is higher than the Young's modulus of the portion of the seat that includes the contact surface. A device for acquiring biological signals. [Form 5] In the biosignal acquisition device described in Embodiment 4, The noise reduction member is arranged so as to surround a portion of the side surface in the thickness direction over the entire circumference of the sensor in a biosignal acquisition device. [Form 6] In the biosignal acquisition device described in Embodiment 4 or Embodiment 5, The system is equipped with multiple sensors (10d, 10e), The plurality of sensors include a first sensor (10d) positioned in contact with the noise reduction member, and a second sensor (10e) that is not in contact with the noise reduction member but is positioned in contact with the seat. The biological information calculation unit is a biological signal acquisition device that obtains the biological information using the difference signal between a signal including the biological signal detected by the first sensor and a signal including the biological signal detected by the second sensor. [Form 7] In a biosignal acquisition device described in any one of the embodiments 4 to 6, The system is equipped with multiple of the aforementioned sensors (10d, 10f), The plurality of sensors include a first sensor (10d) positioned in contact with the noise reduction member, and a third sensor (10f) that is not in contact with the noise reduction member and is positioned inside the seat. The biological information calculation unit is a biological signal acquisition device that obtains the biological information using the difference signal between the signal containing the biological signal detected by the first sensor and the signal containing the biological signal detected by the third sensor. [Explanation of Symbols]

[0061] 30...Seat, 100, 100a~100d...Biometric signal acquisition device, 10, 10a~10f...Sensor, 11, 11d...Noise reduction member, 22...Biometric information calculation unit

Claims

1. A biosignal acquisition device (100, 100a, 100b) used mounted on a seat (30), In the seated position with a human body seated on the aforementioned seat, sensors (10, 10a, 100b, 100c) for detecting the human body's biological signals, A noise reduction member (11) is positioned between the sensor and the seat, in contact with the sensor and the seat, to reduce noise input from the seat to the sensor. A biological information calculation unit (22) that uses the biological signal detected by the sensor to obtain biological information, Equipped with, When viewed in the seated position, with respect to the contact portion of the human body that is in contact with the seat and the seat facing each other, the projection area of ​​the noise reduction member is larger than the projection area of ​​the sensor. The Young's modulus of the noise reduction member is higher than the Young's modulus of the contact portion in the seat. A device for acquiring biological signals.

2. In the biosignal acquisition device (100a) according to claim 1, The system includes multiple sensors (10a, 10b), The plurality of sensors include a first sensor (10a) positioned in contact with the noise reduction member, and a second sensor (10b) that is not in contact with the noise reduction member but is positioned in contact with the seat. The biological information calculation unit is a biological signal acquisition device that obtains the biological information using the difference signal between a signal including the biological signal detected by the first sensor and a signal including the biological signal detected by the second sensor.

3. In the biosignal acquisition device (100b) according to claim 1, The system includes multiple sensors (10a, 10c), The plurality of sensors include a first sensor (10a) positioned in contact with the noise reduction member, and a third sensor (10c) that is not in contact with the noise reduction member and is positioned inside the seat. The biological information calculation unit is a biological signal acquisition device that obtains the biological information using the difference signal between the signal containing the biological signal detected by the first sensor and the signal containing the biological signal detected by the third sensor.

4. A biosignal acquisition device (100c, 100d, 100e) used mounted on a seat, Sensors (10d to 10f) are positioned in contact with the seat (30) and detect the biological signals of the human body when the human body is seated on the seat. A noise reduction member (11d) is positioned in contact with the seat and is positioned in contact with a part of the thickness direction of the sensor, which is a side surface (Ss) of the sensor that intersects with the contact surface (S1) of the sensor that comes into contact with the human body in the seated position, for reducing noise input from the seat to the sensor. A biological information calculation unit (22) that uses the biological signal detected by the sensor to obtain the biological information, Equipped with, The Young's modulus of the noise reduction member is higher than the Young's modulus of the portion of the seat that includes the contact surface. A device for acquiring biological signals.

5. In the biosignal acquisition device according to claim 4, The noise reduction member is arranged so as to surround a portion of the side surface in the thickness direction over the entire circumference of the sensor in a biosignal acquisition device.

6. In the biosignal acquisition device according to claim 4 or claim 5, The system includes multiple sensors (10d, 10e), The plurality of sensors include a first sensor (10d) positioned in contact with the noise reduction member, and a second sensor (10e) that is not in contact with the noise reduction member but is positioned in contact with the seat. The biological information calculation unit is a biological signal acquisition device that obtains the biological information using the difference signal between a signal including the biological signal detected by the first sensor and a signal including the biological signal detected by the second sensor.

7. In the biosignal acquisition device according to claim 4 or claim 5, The system includes multiple sensors (10d, 10f), The plurality of sensors include a first sensor (10d) positioned in contact with the noise reduction member, and a third sensor (10f) that is not in contact with the noise reduction member and is positioned inside the seat. The biological information calculation unit is a biological signal acquisition device that obtains the biological information using the difference signal between the signal containing the biological signal detected by the first sensor and the signal containing the biological signal detected by the third sensor.

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