JP2020092912A - Biological sensor and vehicle seat - Google Patents

Abstract

To provide a biological sensor and a vehicle seat which facilitate accurate detection of biological information.SOLUTION: A biological sensor 10 comprises at least two sensors 11 and 12 for detecting vibration and is configured such that the at least two sensors 11 and 12 form a layer, one of the at least two sensors 11 and 12 being the first sensor 11 used to acquire biological information and another one being the second sensor 12 used to remove noise. Furthermore, disposed between the first sensor 11 and the second sensor 12 is a first cushioning material 14 for attenuating vibration, the first cushioning material 14 being integrally laminated with the first sensor 11 and the second sensor 12.SELECTED DRAWING: Figure 3

Description

The present invention relates to a biosensor and a vehicle seat.

If the health condition of the driver driving the vehicle deteriorates, the driving of the vehicle may be adversely affected. Therefore, it is desirable to detect the deterioration of the health condition in advance and take some measures. As a measure against this, the biological information such as blood flow and blood pressure is estimated based on the measurement results of the pulse wave etc. by the non-contact type blood flow sensor installed so as to be embedded in the seat surface and back surface of the seat. There is known a technique for grasping a driver's health condition (see Patent Document 1).

JP, 2016-168177, A

By the way, when a biometric sensor for detecting biometric information is mounted on a vehicle, vibrations from the vehicle and minute vibrations on the body surface of the living body are likely to cause noise. Therefore, it is necessary to remove noise as necessary, but it may be difficult to remove noise only by using one biometric sensor and it may be difficult to accurately detect biometric information.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a biometric sensor and a vehicle seat that facilitate accurate detection of biometric information.

In order to solve the above problems, the invention according to claim 1 is a biosensor comprising at least two sensors for detecting vibrations, wherein the at least two sensors are configured to form a layer,
One of the at least two sensors is a first sensor used to obtain biological information, and one is a second sensor used to remove noise.

According to a second aspect of the present invention, in the biosensor according to the first aspect, a first cushion material for damping vibration is arranged between the first sensor and the second sensor. The cushion material is integrally laminated with the first sensor and the second sensor.

According to a third aspect of the present invention, in the biosensor according to the second aspect, the first cushion material is made of slab urethane.

According to a fourth aspect of the present invention, in the biosensor according to the second aspect, the first cushion material is composed of a plurality of pyramids.

The invention according to claim 5 is the biological sensor according to any one of claims 1 to 4, wherein the first sensor and the second sensor are provided on the opposite side of the second sensor from the first sensor. Is also provided with a third sensor that is used to form a layer and remove noise.

The invention according to claim 6 is the biosensor according to any one of claims 2 to 4, wherein the first sensor and the second sensor are provided on a side of the second sensor opposite to the first sensor. And a second cushion material for forming a layer together with the first cushion material for damping vibration.

The invention according to claim 7 is the biosensor according to any one of claims 1 to 6, wherein the first sensor and the second sensor have the same shape and the same size. It is characterized by

The invention according to claim 8 is the biosensor according to any one of claims 1 to 6, wherein one of the first sensor and the second sensor is formed to be larger than the other. Characterize.

The invention according to claim 9 is a vehicle seat provided with the biological sensor according to any one of claims 1 to 8,
The first sensor is arranged on the side closer to the living body, and the second sensor is arranged on the side farther from the living body.

According to a tenth aspect of the present invention, in the vehicle seat according to the ninth aspect, a first cushion material for damping vibration is arranged between the first sensor and the second sensor, One cushion material is integrally laminated with the first sensor and the second sensor,
It is characterized by further comprising a calculation means for calculating so as to amplify and correct the amount of vibration attenuation by the first cushion material.

According to the invention of claim 1, since the first sensor and the second sensor for detecting vibration form a layer, the detection signals from the first sensor and the second sensor have the same non-biological information. There will be noise. Therefore, it is possible to extract only the biometric information from the biometric information including the noise component acquired by the first sensor by taking the difference of the noise components. Furthermore, an error does not easily occur in the detection of the noise component between the first sensor and the second sensor forming the layer, and it becomes easy to accurately detect the biological information.

According to the second aspect of the present invention, the vibration transmitted from the first sensor to the second sensor can be damped by the first cushion material, which facilitates extraction of biometric information.
Further, the first cushion material can prevent contact between the first sensor and the second sensor, so that the first sensor and the second sensor are less likely to be damaged.

According to the invention described in claim 3, since the first cushion material is made of slab urethane, it is easy to process and is easily laminated integrally with the first sensor and the second sensor.

According to the invention of claim 4, since the first cushion material is composed of a plurality of cones, it is difficult for the vibration generated on the tip side of the cones to be transmitted to the bottom side of the cones. Therefore, the damping rate of the vibration by the first cushion material can be increased.

According to the invention described in claim 5, since the difference can be obtained in two steps when the difference of the noise component is obtained from the biometric information including the noise component acquired by the first sensor, the extracted living body The accuracy of information can be improved.

According to the invention described in claim 6, since the vibration from the second sensor side can be attenuated by the second cushion material, the accuracy of the extracted biological information can be improved.

According to the invention described in claim 7, since the first sensor and the second sensor are formed in the same shape and in the same size, the detection range of vibration by the first sensor and the second sensor is Can be equal.
In addition, when the first sensor and the second sensor are manufactured as a product forming a layer, the shape of the biosensor can be easily adjusted.

According to the invention as set forth in claim 8, one of the first sensor and the second sensor is formed to be larger than the other, so that the detection range of vibration by one sensor can be widened.

According to the invention of claim 9, the first sensor is arranged on the side closer to the living body, and the second sensor is arranged on the side farther from the living body. Therefore, the first sensor facilitates acquisition of biological information.

According to the tenth aspect of the present invention, the calculation is performed by the calculation means so as to amplify and correct the attenuation of the vibration due to the first cushion material, so that it is possible to obtain the biological information in the state where the noise component is removed. ..

It is a side view which shows the vehicle seat provided with the biometric sensor. It is a perspective view which shows the structure of a biosensor. It is a figure explaining the outline of the system configuration for acquiring biometric information. It is a side view which shows the modification of a biometric sensor. It is a side view which shows the modification of a biometric sensor. It is a side view which shows the modification of a biometric sensor. It is a side view which shows the modification of a biometric sensor.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, various technically preferable limitations for carrying out the present invention are attached to the embodiments described below, but the technical scope of the present invention is not limited to the following embodiments and illustrated examples. Absent.

In FIG. 1, reference numeral 1 indicates a vehicle seat (hereinafter, seat 1) on which a person is seated. The seat 1 is provided in a vehicle such as an automobile. The vehicle may be driven only by manual driving, or may be one that can be driven by switching between automatic driving and manual driving.

The seat 1 includes a seat cushion 2 that supports a person's buttocks and thighs, a seat back 3 whose lower end is supported by the seat cushion 2 to serve as a backrest, and a seat back 3 that supports a person's head. And a headrest 4 that

The seat cushion 2 is mainly composed of a seat cushion frame serving as a skeleton, a cushion pad provided on the seat cushion frame, and a seat cushion frame and a skin covering the cushion pad.

The seat back 3 mainly includes a seat back frame serving as a skeleton, a cushion pad provided on the seat back frame, and a skin covering the seat back frame and the cushion pad.

The seat 1 is provided with a biometric sensor 10 as a means for grasping the health condition of a seated person (living body: seated person). More specifically, the biometric sensor 10 in the present embodiment detects, as biometric information, a pulse wave from the blood flow at a position facing the skin surface of the seated person.
The biometric sensor 10 is preferably provided at a position closer to the seated person, and in the present embodiment, it is provided on the upper surface of the cushion pad at the front end portion of the seat cushion 2 and on the back side of the epidermis. Further, the biometric sensor 10 is arranged so as to be located on the back side of the thigh of the seated person.
In addition, although the biosensor 10 in the present embodiment is provided on the seat cushion 2, it may be provided on the seatback 3 as shown in FIG. 1. In this case as well, the cushion pad in the seat back 3 is provided on the seated person side and on the back side of the outer skin.

The structure of the biometric sensor 10 according to the present embodiment will be described in more detail. As shown in FIG. 2, the biometric sensor 10 includes at least two sensors 11 and 12 for detecting vibration. 12 is configured so as to form a layer, one of at least two sensors 11 and 12 is a first sensor 11 used for acquiring biological information, and one is to remove noise. The second sensor 12 is used for this purpose.
Further, a first cushion material 14 for damping vibration is arranged between the first sensor 11 and the second sensor 12, and the first cushion material 14 together with the first sensor 11 and the second sensor 12 is arranged. It is integrally laminated.

That is, the biometric sensor 10 is one in which the first sensor 11, the second sensor 12, and the first cushion material 14 are integrally laminated, and the first cushion material 14 includes the first sensor 11 and the second sensor material. It is in a state of being sandwiched between the sensor 12.
In the present embodiment, the first sensor 11, the first cushion material 14, and the second sensor 12 are laminated in this order to have a three-layer structure, but the present invention is not limited to this, and the first sensor 11 and the first sensor 11 A two-layer structure including the first sensor 11 and the second sensor 12 may be used as long as the vibration that is transmitted between the two sensors 12 is damped.

The same sensor is used for the first sensor 11 and the second sensor 12. As the first sensor 11 and the second sensor 12 in the present embodiment, piezoelectric sensors that detect pressure waves on the body surface of a seated person are used.
A piezoelectric sensor detects a pressure wave on the body surface of a seated person by means of a piezoelectric element, and is also a contact sensor that contacts the seated person. However, the present invention is not limited to this, and a non-contact sensor that does not need to contact the seated person may be used.

As the sensors that can be used as the first sensor 11 and the second sensor 12, in addition to the piezoelectric sensor, for example, a photoelectric sensor, an electromagnetic wave sensor, an acceleration sensor to which a MEMS (Micro Electro Mechanical System) is applied, or the like can be used. it can.
The photoelectric sensor is a non-contact sensor that irradiates a seated person's body with light from a light emitting unit, receives the reflected light at a light receiving unit, and detects a pulse wave from the reflected light.
The electromagnetic wave type sensor is a non-contact type sensor that emits an electromagnetic wave to the body of a seated person and detects a pulse wave from a reflected wave from the body of the seated person.
The acceleration sensor to which the MEMS is applied uses a MEMS including, for example, a fine weight as a detection element, and is a contact sensor that detects a pulse wave from the displacement of the weight.

The first sensor 11 and the second sensor 12 have the same shape and the same size.
The first cushion material 14 is made of slab urethane, has the same shape as the first sensor 11 and the second sensor 12, and is formed thicker than the first sensor 11 and the second sensor 12. Although the first cushion material 14 in the present embodiment is made of slab urethane, it is not limited to this and may be made of, for example, damping rubber.

When the biometric sensor 10 is provided on the seat 1, the first sensor 11 used to obtain biometric information is arranged on the side closer to the seated person, and the second sensor 12 used to remove noise is from the seated person. It is located on the far side.

Further, as shown in FIG. 3, an arithmetic means connected to each of the first sensor 11 and the second sensor 12 so as to be capable of data communication is provided at any place of the seat 1 or the vehicle. The calculation means in the present embodiment is configured by the control device 5 provided on the seat 1. The control device 5 is also called a so-called ECU (Electronic Control Unit).
That is, the biosensor 10 including the first sensor 11 and the second sensor 12 and the control device 5 are connected to each other in a data communicable manner, whereby a system for acquiring biometric information is constructed.

When acquiring biometric information of a person seated on the seat 1, the biosensor 10 vibrates due to a pulse wave having a small amplitude (arrow Y1 in FIG. 3) and a load change vibration due to a vehicle vibration having a large amplitude (FIG. 3). Two types of vibrations indicated by the arrow Y2) are transmitted.
Then, the first sensor 11 arranged on the side closer to the seated person detects two types of vibrations (arrows Y1, Y2) that are not attenuated by the first cushion material 14. On the other hand, when the second sensor 12 arranged on the side farther from the seated person through the first cushion material 14 does not detect the vibration due to the pulse wave having a small amplitude among the two kinds of vibrations (arrow Y1 in FIG. 3). ′ Indicates the vibration due to the attenuated pulse wave), and at least the load change vibration (arrow Y2′ in FIG. 3) is detected.
That is, by configuring the biosensor 10 so that the first sensor 11 and the second sensor 12 form a layer, the first sensor 11 and the second sensor 12 have the same type of vibration (having a large amplitude). The load change vibration Y2, Y2') due to the vehicle vibration is introduced. The vibration Y1 (Y1′) due to the pulse wave having a small amplitude can be detected by the first sensor 11, but is difficult to be transmitted to the second sensor 12.

The control device 5, which is a calculation means, includes a memory in which a calculation program is stored, and uses a detection signal (data) detected by the first sensor 11 and the second sensor 12 to derive a pulse wave by the calculation program. be able to. At this time, the control device 5 calculates so as to amplify and correct the damping amount of the vibration caused by the first cushion material 14.
That is, the detection signal detected by the first sensor 11 and transmitted to the control device 5 includes not only the pulse wave to be extracted but also a noise component. In order to remove the noise component, the control device 5 detects the detection signal transmitted by the first sensor 11 to the control device 5 and the detection signal transmitted by the second sensor 12 to the control device 5. The calculation is performed so as to take the difference with. However, as described above, since the vibration due to the pulse wave is difficult to be transmitted to the second sensor 12 and the pulse wave may not be accurately obtained even if the difference is simply calculated, the vibration due to the first cushion material 14 may not be obtained during the calculation. A process of amplifying and correcting the attenuation is performed. This makes it possible to remove only the noise component and extract only the pulse wave detection signal (biological information).

When the biological sensor 10 has a two-layer structure including the first sensor 11 and the second sensor 12 that do not include the first cushion material 14, vibration Y1 (Y1′) due to a pulse wave having a small amplitude is generated by the second sensor. It becomes easy to reach 12. In such a case, it is not necessary to amplify and correct the amount of vibration attenuation by the first cushion material 14.

The extracted pulse wave detection signal can be used, for example, to estimate the blood pressure of a seated person. When the blood pressure is estimated from the pulse wave, for example, another biosensor 10 may be provided at another portion of the sheet 1 to derive the pulse wave velocity, or else the IEEE standard (IEEE1708-2014) may be satisfied. It may be derived from the blood pressure estimation method of.

According to the present embodiment, since the first sensor 11 and the second sensor 12 that detect vibration form a layer, the detection signals from the first sensor 11 and the second sensor 12 are the same, not biological information. Noise will be introduced. Therefore, it is possible to extract only the biometric information from the biometric information including the noise component acquired by the first sensor 11 by taking the difference of the noise components. Further, an error does not easily occur in the detection of the noise component between the first sensor 11 and the second sensor 12 forming the layer, and it becomes easy to accurately detect the biological information.

Further, since the vibration transmitted from the first sensor 11 to the second sensor 12 can be damped by the first cushion material 14, it becomes easy to extract biological information.
Furthermore, since the first cushion material 14 can prevent the first sensor 11 and the second sensor 12 from contacting each other, the first sensor 11 and the second sensor 12 are less likely to be damaged.

Further, since the first cushion material 14 is made of slab urethane, it is easy to process and is easy to be integrally laminated with the first sensor 11 and the second sensor 12.

Further, since the first sensor 11 and the second sensor 12 are formed in the same shape and the same size, the vibration detection ranges of the first sensor 11 and the second sensor 12 can be equalized. ..
Furthermore, when the first sensor 11 and the second sensor 12 are manufactured as a product forming a layer, the shape of the biosensor 10 is easily arranged.

Further, since the first sensor 11 is arranged on the side closer to the seated person and the second sensor 12 is arranged on the side farther from the seated person, it becomes easier for the first sensor 11 to acquire biological information.

In addition, since the control unit 5 as the calculation unit performs the calculation so as to amplify and correct the attenuation amount of the vibration due to the first cushion material, it is possible to obtain the biological information in the state in which the noise component is removed.

[Modification]
Note that the embodiments to which the present invention can be applied are not limited to the above-described embodiments, and can be modified as appropriate without departing from the spirit of the present invention. Hereinafter, modified examples will be described. The modifications described below may be combined as much as possible.
Further, in each of the following modified examples, elements common to the above-described embodiment are denoted by common reference numerals, and description thereof will be omitted or simplified.

[Modification 1]
As shown in FIG. 4, the biosensor 10A in the present modification forms a layer together with the first sensor 11 and the second sensor 12 on the opposite side of the second sensor 12 from the first sensor 11 to remove noise. A third sensor 13 used for this purpose is provided so as to have a four-layer structure.
That is, the first cushion material 14 is provided between the first sensor 11 and the second sensor 12, and the second sensor 12 is provided between the first cushion material 14 and the third sensor 13 so as to be laminated. ing.

As the third sensor 13, the same type of sensor as the first sensor 11 and the second sensor 12 is used.
Further, the third sensor 13 is also connected to the control device 5, which is an arithmetic means, so that data communication is possible.

According to this modification, when the difference of the noise component is obtained from the biological information including the noise component obtained by the first sensor 11, the difference is obtained in two steps by the second sensor 12 and the third sensor 13. Therefore, the accuracy of the extracted biometric information can be improved.

[Modification 2]
As shown in FIG. 5, the biological sensor 10B in the present modification has a layer on the side opposite to the first sensor 11 in the second sensor 12 together with the first sensor 11 and the second sensor 12, and the first cushion material 14. A second cushion member 15 for forming and damping vibration is provided to form a four-layer structure.
That is, the first cushion material 14 is provided between the first sensor 11 and the second sensor 12, and the second sensor 12 is provided between the first cushion material 14 and the second cushion material 15 in a stacked state. doing.

The second cushion material 15 is made of slab urethane like the first cushion material 14, but is not limited to this, and may be made of another material such as damping rubber.
Further, the first cushion material 14 and the second cushion material 15 have the same shape and the same size.

According to the present modification, the vibration from the second sensor 12 side (that is, the side farther from the seated person: for example, the floor side of the vehicle) can be damped by the second cushion material 15, and thus the vibration is extracted. The accuracy of biometric information can be improved.

[Modification 3]
As shown in FIGS. 6A and 6B, one of the biosensors 10C and 10D according to the present modification is larger than the other of the first sensor 11 (11C) and the second sensor 12 (12D). Is configured to be.

In the example shown in FIG. 6A, the first sensor 11C is formed larger than the second sensor 12.
In the example shown in FIG. 6B, the second sensor 12D is formed larger than the first sensor 11.
Although the first cushion material 14 is formed to have a size suitable for a sensor having a small size in both of the examples shown in FIGS. 6A and 6B, it has a size suitable for a sensor having a large size. It may be formed in. Further, it may be formed in a substantially frustum shape so as to gradually spread from the small size sensor to the large size sensor.

According to this modification, one of the first sensor 11 (11C) and the second sensor 12 (12D) is formed larger than the other, so that the detection range of vibration by one sensor can be widened. it can.

[Modification 4]
As shown in FIG. 7, the biosensor 10E in the present modified example is configured to include a first cushion material including a plurality of cone-shaped bodies 14E.
In addition, the first sensor 11E and the second sensor 12E are configured by sensors formed in a film shape. However, the first sensor 11E and the second sensor 12E may be configured by the non-film-shaped sensors 11 and 12 similar to the above-described embodiment.

The plurality of cone-shaped bodies 14E utilize a cone-shaped property that makes it difficult to transmit the vibration generated on the tip side to the bottom side. Therefore, the plurality of pyramids 14E do not need to be soft, such as urethane foam, and may be made of a hard material that does not impair the sitting comfort of the seated person.

According to this modification, since the first cushion material is composed of the plurality of conical bodies 14E, it is difficult for the vibration generated on the tip side of the conical bodies 14E to be transmitted to the bottom surface side of the conical bodies 14E. Therefore, the damping rate of the vibration by the first cushion material can be increased.

[Modification 5]
In the above-described embodiment and modification, two types of vibrations, that is, vibrations due to a pulse wave with a small amplitude and load change vibrations due to a vehicle vibration with a large amplitude are transmitted to the biometric sensor 10, and based on this, a seated person is seated. However, in the present modification, biological information other than the pulse wave is acquired.
Examples of biological information other than pulse waves include biological information that can be acquired based on vibration detected by a sensor, such as heartbeat, respiration, and muscle contraction.
According to this modification, the laminated structure of the first sensor 11 and the second sensor 12 described in the above-described embodiments and modifications can be applied to acquire various biological information other than the pulse wave.

1 seat 2 seat cushion 3 seat back 4 headrest 5 control device 10 biometric sensor 10A biometric sensor 10B biometric sensor 10C biometric sensor 10D biometric sensor 10E biometric sensor 11 first sensor 11C first sensor 11E first sensor 12 second sensor 12D second Sensor 12E Second sensor 13 Third sensor 14 First cushion material 14E Conical body 15 Second cushion material

Claims (10)

A biosensor comprising at least two sensors for detecting vibrations, the at least two sensors being configured to form a layer,
Of the at least two sensors, one is a first sensor used to obtain biometric information, and one is a second sensor used to remove noise sensor. A first cushion material for damping vibration is disposed between the first sensor and the second sensor, and the first cushion material is integrally laminated with the first sensor and the second sensor. The biosensor according to claim 1, wherein the biosensor is a biosensor. The biosensor according to claim 2, wherein the first cushion material is made of slab urethane. The biosensor according to claim 2, wherein the first cushion material is composed of a plurality of conical bodies. On the side opposite to the first sensor in the second sensor, a layer is formed with the first sensor and the second sensor, and a third sensor used for removing noise is provided. The biosensor according to any one of claims 1 to 4. On the opposite side of the second sensor from the first sensor, a second cushion material is provided to form a layer together with the first sensor and the second sensor and the first cushion material, and to damp vibrations. The biosensor according to any one of claims 2 to 4, wherein: The biosensor according to any one of claims 1 to 6, wherein the first sensor and the second sensor have the same shape and the same size. The biosensor according to claim 1, wherein one of the first sensor and the second sensor is formed larger than the other. A vehicle seat provided with the biosensor according to claim 1.
The vehicle seat, wherein the first sensor is arranged on the side closer to the living body, and the second sensor is arranged on the side farther from the living body. A first cushion material for damping vibration is disposed between the first sensor and the second sensor, and the first cushion material is integrally laminated with the first sensor and the second sensor. And
The vehicle seat according to claim 9, further comprising a calculation unit that calculates and amplifies and corrects a damping amount of vibration by the first cushion material.

Images