JP2017136304A - Driver monitoring device, monitoring device, monitoring method, program, and seat belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driver monitoring device, monitoring device, monitoring method, program, and seat belt, for simply grasping a state of the body of a measurement subject by using a belt.SOLUTION: A plurality of electrodes and a plurality of curvature sensors are provided on a seat belt, the electrodes and curvature sensors being electrically connected to a monitoring device. The monitoring device estimates a shape of the seat belt by using curvature data acquired through the curvature sensors. Or, the monitoring device creates an image based on impedance between the electrodes, the impedance being obtained from the electrodes. The monitoring device uses at least either the shape of the seat belt or the created image to determine a state of a driver on the basis of the shape of the seat belt.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a driver monitoring device, a monitoring device, a monitoring method, a program, and a seat belt.

  An electrical impedance tomography (hereinafter simply referred to as “EIT”) measuring device allows a weak current to flow from a pair of electrodes affixed on the body surface, and from the potential difference generated on the body surface, the conductivity distribution or conductivity in the living body. This is a technique for imaging the distribution of changes. EIT (Electrical Impedance Tomography) can acquire tomographic images by simply passing a weak current, so there is no problem of exposure compared to X-ray CT (Computed tomography), miniaturization, long-time measurement, and real-time measurement. There is an advantage that it is easy.

  In the EIT measurement, for example, a plurality of electrodes are used. These electrodes are brought into contact with the periphery of the measurement target site, and signal cables individually connected to the electrodes are routed to be connected to the measurement circuit.

  As a related technique, Patent Document 1 discloses an EIT measurement apparatus that combines an EIT technique and a technique for estimating the contour and shape of a body.

International Publication No. 2015/002210

  By the way, although the above-mentioned EIT technique is considered to be used for medical treatment or the like, further technical development is desired for use in grasping the state of a human body or the like.

  Therefore, an object of the present invention is to provide a driver monitoring device, a monitoring device, a monitoring method, a program, and a seat belt that can solve the above-described problems.

  According to the first aspect of the present invention, the driver monitoring device is electrically connected to the curvature sensor of a seat belt provided with a plurality of curvature sensors, and the curvature data acquired via the curvature sensor is stored in the driver monitoring device. A shape estimation unit that estimates the shape of the seat belt, and a state determination unit that determines the state of the driver based on the shape of the seat belt.

  In the above driver monitoring device, the state determination unit estimates a range in which the seat belt contacts the driver, and drives the curvature sensor located in the contact range.

  In the above-described driver monitoring device, the state determination unit determines normality or abnormality of the driver state by using any one or more of the shape of the seat belt, the heart rate, and the ventilation state.

  In the above-described driver monitoring device, the seat belt is electrically connected to the electrode of the seat belt provided with a plurality of electrodes, and the state determination unit includes energization to the plurality of electrodes and the electrodes. The tomographic image of the driver in a range where the seat belt contacts the driver is generated based on the voltage signal generated during the period, and the state of the driver is determined based on the tomographic image.

  In the above-described driver monitoring device, the state determination unit detects the heart rate of the driver based on energization to the plurality of electrodes and a voltage signal generated between the electrodes.

  In the above-described driver monitoring device, the state determination unit detects the ventilation state of the driver based on energization to the plurality of electrodes and a voltage signal generated between the electrodes.

  The above-described driver monitoring device includes a recording unit that records one or more of the tomographic image, the heart rate, the ventilation state, and the driver state.

  The above-described driver monitoring device includes a display processing unit that displays any one or more of the tomographic image, the heart rate, the ventilation state, and the driver state on a monitor.

  In the above driver monitoring apparatus, the state determination unit operates a warning sensor when it is determined that the state of the driver is abnormal.

  The above-described driver monitoring device includes a correction unit that corrects output information of the curvature sensor based on the shape of the seat belt when the seat belt is in a predetermined state where the seat belt is not used.

  According to the second aspect of the present invention, the driver monitoring device is electrically connected to the electrode of the seat belt provided with a plurality of electrodes, energized to the plurality of electrodes, and the electrodes A state determination unit that generates a tomographic image of the driver in a range where the seat belt contacts the driver based on a voltage signal generated therebetween, and determines the state of the driver based on the tomographic image. .

  According to the third aspect of the present invention, the monitoring device is connected to a body contact member provided with a plurality of electrodes, and based on an electrical signal obtained from the electrodes, a tomographic image of the person being measured, a heartbeat A state determination unit that calculates one or a plurality of state information of the number and the ventilation state, and determines normality or abnormality of the state of the subject using the state information.

  According to the fourth aspect of the present invention, the monitoring device is connected to a body contact member provided with a plurality of curvature sensors, and based on a signal obtained from the curvature sensors, A state determination unit that calculates one or a plurality of state information of a heart rate and a ventilation state, and determines the state of the measurement subject using the state information.

  According to a fifth aspect of the present invention, there is provided a monitoring method in which a monitoring device connected to a body contact member provided with a plurality of electrodes is connected to a person to be measured based on an electrical signal obtained from the electrodes. One or more state information of a tomographic image, a heart rate, and a ventilation state is calculated, and normality or abnormality of the state of the measurement subject is determined using the state information.

  According to the sixth aspect of the present invention, the monitoring method is such that the monitoring device connected to the body contact member provided with a plurality of curvature sensors is based on a signal obtained from the curvature sensor. One or a plurality of state information of body motion, heart rate, and ventilation state is calculated, and the state of the subject is determined using the state information.

  According to the seventh aspect of the present invention, the program causes the computer of the monitoring device connected to the body contact member provided with a plurality of electrodes to be measured based on the electrical signal obtained from the electrodes. One or more state information of a tomographic image, a heart rate, and a ventilation state is calculated, and the state information is used to function as state determination means for determining normality or abnormality of the measurement subject.

  According to the eighth aspect of the present invention, the program is configured to measure a computer of a monitoring device connected to a body contact member provided with a plurality of curvature sensors based on a signal obtained from the curvature sensor. One or a plurality of state information of a person's body movement, heart rate, and ventilation state is calculated, and functions as a state determination unit that determines the state of the measurement subject using the state information.

  According to the ninth aspect of the present invention, the seat belt includes a plurality of electrodes arranged periodically and a plurality of curvature sensors arranged periodically in parallel with the plurality of electrodes.

  According to the present invention, the above-described seat belt includes an output unit that detects use of the seat belt and outputs a use detection signal to the driver monitoring device.

  According to the present invention, the state of the body of the person to be measured can be easily grasped by the belt.

It is a figure which shows the driver | operator monitoring apparatus and seatbelt by 1st Embodiment. It is the 1st figure showing the internal configuration of the seatbelt concerning a 1st embodiment. It is a figure which shows the function structure of the driver | operator monitoring apparatus which concerns on 1st Embodiment. It is a figure explaining the composition of the seatbelt and driver monitoring device concerning a 1st embodiment. It is a figure which shows the example of the tomographic image which the state determination part by 1st Embodiment produced | generated. It is a figure which shows the structure of the curvature sensor by 1st Embodiment. It is a figure which shows the example of arrangement | positioning of the strain gauge by 1st Embodiment. It is a figure which shows the comparison of the thickness of the signal wire | line connected to the strain gauge by 1st Embodiment, and the signal wire | line in a strain gauge. It is a figure which shows the example of a connection which connected the bridge | bridging and signal conversion module by 1st Embodiment many-to-one. It is a figure which shows the example of the shape of a part of seat belt by 1st Embodiment. It is a 1st figure which shows the partial shape estimation process of the shape estimation part by 1st Embodiment. It is a 2nd figure which shows the partial shape estimation process of the shape estimation part by 1st Embodiment. It is a 2nd figure which shows the internal structure of the seatbelt by 1st Embodiment. It is a figure which shows the outline | summary of the process which specifies the contact range X by 1st Embodiment. It is a 1st figure which shows the processing flow of the driver | operator monitoring apparatus by 1st Embodiment. It is a 2nd figure which shows the processing flow of the driver | operator monitoring apparatus by 1st Embodiment. It is a 3rd figure which shows the processing flow of the driver | operator monitoring apparatus by 1st Embodiment. It is a 4th figure which shows the processing flow of the driver | operator monitoring apparatus by 1st Embodiment. It is a 2nd figure which shows the function structure of the driver | operator monitoring apparatus by 1st Embodiment. It is a figure which shows the monitoring apparatus and suppression belt by 2nd Embodiment.

<First Embodiment>
Hereinafter, a driver monitoring device, a driver monitoring method, and a program according to a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating a driver monitoring device and a seat belt according to the first embodiment.
As shown in FIG. 1, the driver monitoring device 2 is connected to an electric circuit configured on a flexible substrate built in the seat belt 1 via a communication cable 3.
As an example, the seat belt 1 includes an electric circuit including at least a plurality of electrodes periodically arranged and a plurality of curvature sensors periodically arranged in parallel with the plurality of electrodes.
The driver monitoring device 2 estimates the shape of the seat belt 1 based on curvature data acquired via a curvature sensor built in the seat belt 1. The driver monitoring device 2 determines the state of the driver based on the shape of the seat belt 1.
The driver state may be driver awareness, tomographic image, heart rate, ventilation state, body movement, and the like. The driver monitoring device 2 determines normality or abnormality of the driver state using any one or more of these driver states.

A flexible substrate 14 is provided inside the seat belt 1. Specifically, the flexible substrate 14 is sandwiched between two overlapping belts that constitute the seat belt 1.
FIG. 2 is a first diagram illustrating an internal configuration of the seat belt according to the first embodiment.
As shown in FIG. 2, the seat belt 1 has a configuration in which a plurality of electrode pads 12 </ b> A to 12 </ b> H are arranged at equal distances P (periodic arrangement) on a belt-like flexible substrate 14. Similarly, on the flexible substrate 14, a plurality of curvature sensors 150 </ b> A to 150 </ b> H are periodically arranged at equal intervals P in parallel with the electrode pads 12 </ b> A to 12 </ b> H. The plurality of electrode pads 12A to 12H are collectively referred to as an electrode pad 12. The plurality of curvature sensors 150 </ b> A to 150 </ b> H are collectively referred to as a curvature sensor 150. Although eight electrode pads 12 and eight curvature sensors 150 are shown in FIG. 2, a larger number of electrode pads 12 and curvature sensors 150 may be provided.

The electrode pads 12A to 12H and the curvature sensor 150 are provided inside the seat belt 1 so as to be positioned in a measurement target range such as a chest and an abdomen when the seat belt 1 is wound around a driver's body. Yes.
The seat belt 1 may have a strain gauge for each of the curvature sensors 150A to 150H. The curvature sensor 150 has two strain gauges, and by using a two-active gauge method in which a pair of strain gauges for each measurement point is connected to one bridge circuit, temperature correction automation and higher sensitivity of the curvature sensors 150A to 150H are achieved. High accuracy can be realized.
Alternatively, the seat belt 1 may have a temperature sensor at the same position on the back surface of each of the curvature sensors 150A to 150H. The driver monitoring device 2 may correct the curvature data acquired by the curvature sensors 150A to 150H based on the temperature data acquired by the temperature sensor. By doing in this way, high sensitivity and high precision of curvature sensors 150A-150H are realizable.

  The measurement circuit 11 is an electric circuit that mediates the exchange of electric signals between the driver monitoring device 2 and the electrode pads 12A to 12H and the curvature sensors 150A to 150H. For example, the measurement circuit 11 includes a circuit that amplifies an electrical signal output from the curvature sensors 150A to 150H and performs A / D (Analog / Digital) conversion.

FIG. 3 is a first diagram illustrating a functional configuration of the driver monitoring apparatus according to the first embodiment.
The driver monitoring device 2 according to the first embodiment is configured by a computer. The driver monitoring device 2 may be incorporated into the car navigation system.

As shown in FIG. 3, the driver monitoring device 2 includes a CPU (Central Processing Unit) 200 that controls the entire operation, and a work area of the CPU 200 when executing a measurement program or the like used for EIT measurement. A RAM (Random Access Memory) 210, and an HDD (Hard Disk Drive) 211 as storage means for storing various programs and tomographic images acquired by the state determination unit 201.
The operation input unit 212 includes, for example, operation buttons, a touch panel, and the like, and receives input of various operations by an operator such as a driver. The image display unit 213 is a liquid crystal display or the like, and displays information necessary for EIT measurement, acquired tomographic images, and the like.
The external interface 214 is a communication interface for performing communication with an external device. In particular, in the present embodiment, the external interface 214 is connected to the seat belt 1 via the dedicated communication cable 3 and acquires various signals from the seat belt 1. It is a functional part to do.
The CPU 200, RAM 210, HDD 211, operation input unit 212, image display unit 213, and external interface 214 are electrically connected to each other via a system bus 215.

As shown in FIG. 3, the CPU 200 executes a predetermined measurement program in a state where the seat belt 1 is used, and exhibits functions as the state determination unit 201 and the shape estimation unit 202 at the time of execution.
The state determination unit 201 acquires a tomographic image of the measurement target unit X while energizing the plurality of electrode pads 12A to 12H and acquiring a voltage signal generated between the electrode pads 12A to 12H.
Moreover, the shape estimation part 202 estimates the shape of the seatbelt 1 based on the curvature data acquired via the curvature sensors 150A-150H.

FIG. 4 is a diagram illustrating the configuration of the seat belt and the driver monitoring device according to the present embodiment.
Hereinafter, the function of the state determination unit 201 will be described with reference to FIGS. 4 and 5. As shown in FIG. 4, a current source I and a voltmeter V are connected between the electrode pads 12A to 12H. The state determination unit 201 has a function of controlling the current source I and the voltmeter V.

  The state determination unit 201 controls the flow of a predetermined weak current between the pair of electrode pads 12A to 12H (for example, between the electrode pad 12A and the electrode pad 12B) via the current source I. . The state determination unit 201 measures a potential difference generated between each of the other electrode pads (electrode pads 12C to 12H) via the voltmeter V while a weak current is passed through the pair of electrode pads. By sequentially changing the electrode pads through which the current flows 12B and 12C, 12C and 12D,... And measuring the potential difference repeatedly, the resistivity distribution in the tomography of the measurement target portion X can be acquired.

The state determination unit 201 generates a tomographic image using, for example, a general back projection method, based on the resistivity distribution on the tomographic plane as the measurement target acquired as described above. The state determination unit 201 displays the generated tomographic image on the image display unit 213 so that a driver, an emergency team, or the like visually recognizes the tomographic image. As a method for generating a tomographic image using EIT in the state determination unit 201, a known technique may be used.
Although FIG. 4 shows a situation in which the current source I and the voltmeter V are provided between the different electrode pads 12, the current source I and the voltmeter V may be provided between the electrode pads 12. A four-electrode method or a two-electrode method may be used to measure the current value or voltage value between the electrode pads 12. The electrode pad 12 may have any structure.

FIG. 5 is a diagram illustrating an example of a tomographic image generated by the state determination unit.
FIG. 5 is a tomographic image of the chest of the measurement subject acquired by the state determination unit 201, and the region with higher electrical impedance is shown in darker shades. According to FIG. 5, it is possible to know that lung fields whose electrical impedance is measured to be high due to the presence of air are present on the left and right.
As a method for the state determination unit 201 to generate a tomographic image, a method using the finite element method (FEM) in addition to the back projection method described above, or a method combining the finite element method and the back projection method is considered. It is done. When the back projection method is used, the state determination unit 201 can image only a relative change based on a certain state, but by using the finite element method, the absolute electric resistance on the tomographic plane is obtained. A tomographic image based on the rate [Ωm] can be formed.

FIG. 6 is a diagram showing the configuration of the curvature sensor.
The curvature sensor 150 measures the curvature of the seat belt 1 at the position where the curvature sensor 150 is disposed. As shown in FIG. 6, the curvature sensor 150 includes a bridge (Wheatstone bridge) 151 in which resistors 152-1 and 152-2, strain gauges 153-1 and 153-2 are combined, and an amplifier 156. Is done. The bridge 151 receives a DC voltage from the power supply unit 111 when measuring the curvature. The current from the power supply unit 111 flows through the bridge 151 to the ground (zero potential point).

The output of the curvature sensor 150 is transmitted to the driver monitoring device 2 via the A / D converter (analog-digital converter) 157 and the serial communication circuit 114.
Hereinafter, the resistors 152-1 and 152-2 are collectively referred to as a resistor 152. Further, the strain gauges 153-1 and 153-2 are collectively referred to as a strain gauge 153.
The function of each circuit shown in FIG. 6 may be printed on the flexible substrate 14.

FIG. 7 is a diagram illustrating an arrangement example of strain gauges.
The figure shows an example of a cross section of the seat belt 1 as viewed from the side, and an arrow B11 indicates the longitudinal direction of the seat belt 1.
Each of the strain gauges 153 is arranged in a direction in which the direction in which the strain (strain) is detected coincides with the longitudinal direction of the seat belt 1. Further, as shown in FIG. 7, the strain gauges 153-1 and 152-2 are arranged with the flexible substrate 14 interposed therebetween. For example, the strain gauge 153-1 is disposed on the front belt 41 side of the seat belt 1 when viewed from the flexible substrate 14, and the strain gauge 153-2 is disposed on the back belt 42 side of the seat belt 1 when viewed from the flexible substrate 14. Yes.

  With this arrangement, when the flexible substrate 14 is bent, a difference is generated between the impedance of the strain gauge 153-1 and the impedance of the strain gauge 153-2. When the driver wears the seat belt 1 and the flexible substrate 14 is bent convexly on the front surface side and concave on the back surface side, the strain gauge 153-1 disposed on the front surface side of the seat belt 1 is extended. Impedance increases. On the other hand, the strain gauge 153-2 disposed on the back side of the seat belt 1 is contracted to reduce the impedance.

Due to the difference in impedance, a voltage (potential difference) is generated between point P11 and point P12 in FIG. The magnitude of the voltage between the point P11 and the point P12 indicates the magnitude of bending of the seat belt 1 at the position where the strain gauge 153 is disposed on the seat belt 1 (position where the curvature sensor 150 is disposed).
The amplifier 156 converts the voltage between the point P11 and the point P12 into the curvature of the seat belt 1 at the installation position of the strain gauge 153. Specifically, a calibration curve indicating the relationship between the voltage between the points P11 and P12 and the curvature of the seat belt 1 is obtained in advance, and the amplifier 156 calculates the voltage between the points P11 and P12. It is set to amplify according to this calibration curve.

Note that the bridge 151 may include only one strain gauge 153. Specifically, the bridge 151 may include a resistor instead of one of the strain gauges 153-1 and 153-2. As the resistance in this case, a resistance having the same resistance value as that when the strain gauge 153 is not bent is used.
On the other hand, when the bridge 151 includes one strain gauge 153 as shown in FIG. 6, the voltage difference between the point P11 and the point P12 becomes larger than the case where the bridge 151 includes only one strain gauge 153, and the curvature is increased. The accuracy of the sensor 150 is improved. In addition, since the bridge 151 includes one strain gauge 153, the bridge 151 is less affected by temperature changes than when the bridge 151 includes only one strain gauge 153.

Note that the wiring in the strain gauge 153 is thinned and the wiring connected to the strain gauge 153 is thickened. Thereby, the accuracy of the curvature sensor 150 can be improved. This point will be described with reference to FIG.
FIG. 8 is a diagram showing a comparison of the thickness of the signal line connected to the strain gauge and the signal line in the strain gauge.
In the drawing, a wiring W11 in the strain gauge 153 and a wiring W12 connected to the strain gauge 153 are shown.

When the strain gauge 153 is bent, the impedance of the strain gauge 153 is changed by changing the length and / or width of the wiring W11. The strain gauge 153 indicates the magnitude of bending by this change in impedance.
In order to easily change the impedance of the strain gauge 153, the width of the wiring W11 is narrowed (the wiring W11 is narrowed). As a result, when the strain gauge 153 is bent and the width of the wiring W11 changes, the rate of change from the original width increases.

On the other hand, in order to accurately measure the impedance of the strain gauge 153, it is preferable that the resistance between the strain gauge 153 and the impedance detection circuit (the amplifier 156 in the example of FIG. 6) is small. Therefore, the width of the wiring W12 is increased (the wiring W12 is thickened).
In this way, the accuracy of the curvature sensor 150 can be improved by thinning the wiring in the strain gauge 153 and thickening the wiring connected to the strain gauge 153.

The A / D converter 157 converts an analog signal (for example, a voltage value proportional to the curvature) output from the amplifier 156 into a digital signal.
The serial communication circuit 114 transmits the digital signal output from the A / D converter 157 to the driver monitoring device 2 by serial communication. Accordingly, the serial communication circuit 114 transmits the digital signal output from the A / D converter 157 to the driver monitoring device 2. For example, the serial communication circuit 114 is provided for each curvature sensor 150, and the first serial communication unit 110 includes the serial communication circuit 114.

As a communication method of the serial communication circuit 114, for example, various serial communication methods such as SPI (Serial Peripheral Interface) or I2C (Inter-Integrated Circuit) (I2C is a registered trademark) can be used.
When the serial communication circuit 114 performs serial communication, the sensor value by the curvature sensor 150 can be communicated with a small number of wires, such as about 3 to 5. Since a large number of wirings are not necessary, it is possible to avoid an increase in the size of the seat belt 1 such that the belt constituting the seat belt becomes wider or thicker.

Hereinafter, a combination of the amplifier 156, the A / D converter 157, and the serial communication circuit 114 is referred to as a signal conversion module 181. The signal conversion module 181 converts an analog signal (voltage between the points P11 and P12) by the bridge 151 into a digital signal indicating a curvature, and further converts it into a digital signal according to the serial communication standard.
Here, the signal conversion module 181 is configured as a single IC chip, or the signal conversion module 181 is configured as a single substrate. This eliminates the need to design the signal conversion module 181 for each curvature sensor 150 (the bridge 151 of the curvature sensor 150). In this respect, when designing the seat belt 1, the signal conversion module 181 can be arranged relatively easily.

Note that one signal conversion module 181 may transmit the curvature of the plurality of bridges 151.
FIG. 9 is a diagram illustrating a connection example in which bridges and signal conversion modules are connected in a many-to-one relationship.
In the example of FIG. 4, the four bridges 151 are connected to the signal conversion module via the multiplexer 182.

  The multiplexer 182 switches the bridge 151 connected to the signal conversion module 181 in a time division manner. The signal conversion module 181 converts the voltage of the bridge 151 connected via the multiplexer 182 (the voltage between the point P11 and the point P12 in FIG. 6) into a digital signal indicating the curvature and transmits the digital signal by serial communication. To do. Thereby, a curvature can be transmitted by a relatively small number of signal conversion modules.

  On the other hand, when the bridge 151 and the signal conversion module are arranged one-on-one, the signal conversion module 181 is arranged near the bridge 151. Thereby, it is possible to prevent a decrease in the S / N ratio (Signal To Noise Ratio) of the signal (voltage in the bridge 151) acquired by the signal conversion module 181. In this respect, the curvature sensor 150 can measure the curvature with high accuracy.

  Further, when the bridge 151 and the signal conversion module 181 are arranged one-on-one, the length of the wiring between the bridge 151 and the signal conversion module 181 is the same in any combination of the bridge 151 and the signal conversion module 181. Align. Thereby, the dispersion | variation in the measurement precision of the curvature for every combination of the bridge 151 and the signal conversion module 181 can be reduced. The signal conversion module 181 may be built in the measurement circuit 11.

The shape estimation unit 202 detects the contact (proximity) range X of the measurement target (chest and abdomen) on the seat belt 1 using the measurement result of the curvature sensor 150 and the like, and estimates the seat belt shape.
The shape estimation unit 202 communicates with the measurement circuit 11 by serial communication. In particular, the shape estimation unit 202 receives various data transmitted by the measurement circuit 11 such as a measured value of curvature.
The shape estimation unit 202 determines whether to start detecting the contact range X and estimating the seat belt shape. Specifically, the shape estimation unit 202 determines whether or not the conditions for detecting the contact range X of the seat belt with respect to the measurement target and the estimation process of the seat belt shape are satisfied. The driver monitoring device 2 determines that the start condition is satisfied when, for example, a switch provided on the buckle that engages the seat belt 1 is ON, and the state determination unit 201 and the shape estimation unit 202 are determined. Notify The switch provided on the buckle may be configured to be turned on when the metal plate provided on the seat belt is engaged with the buckle when the seat belt is used. By determining that the start condition is satisfied, the state determination unit 201 and the shape estimation unit 202 start processing.

When the shape estimation unit 202 determines that the start condition is satisfied, the shape estimation unit 202 estimates the seat belt shape of the contact range X of the seat belt with respect to the measurement target based on the sensor value of the curvature sensor 150 (the curvature detected by the curvature sensor 150).
The shape estimation process performed by the shape estimation unit 202 will be described with reference to FIGS.

FIG. 10 is a diagram showing an example of the shape of a part of the seat belt.
The figure shows a state in which the flexible substrate 14 and the plurality of curvature sensors 150 provided on the flexible substrate 14 are bent. The partial shape of the flexible substrate 14 can be regarded as the partial shape of the seat belt 1 (partial shape of the belt portion). Here, the curvature sensor 150 is distinguished by being expressed as a curvature sensor 150-1, a curvature sensor 150-2, a curvature sensor 150-3,.

In the example of FIG. 10, the curvature sensors 150 are arranged at equal intervals (intervals of distance d). A range of distance d is assumed around each of the curvature sensors 150, and ends of these ranges are indicated by points P0, P1, P2, P3,. The partial shape estimation unit 241 obtains a partial shape by approximating each of these ranges with an arc of curvature indicated by the curvature sensor 150.
Further, it is assumed that the curvature of the curvature sensor 150-1 is C1, the curvature of the curvature sensor 150-2 is C2, and the curvature of the curvature sensor 150-3 is C3.

FIG. 11 is a first diagram illustrating a partial shape estimation process of the shape estimation unit.
FIG. 11 shows the curvature sensor 150-1, one end (point P0) and the other end (point P ₁ ) of the range of the distance d centering on the curvature sensor 150-1 in the coordinate system based on the origin O. Is shown. The value of the distance d is a known value, shape estimation unit 202 obtains a curvature C _1, which curvature sensor 150a measures. The shape estimation unit 202 calculates the curvature radius R ₁ from the curvature C ₁ based on the equation (1).

Formula (1) is a general formula. In Formula (1), C represents a curvature, and R represents a curvature radius.
Based on the radius of curvature R ₁ and the curvature C ₁ , the shape estimation unit 202 determines the center angle of the arc that approximates the range of the distance d centered on the curvature sensor 150-1 (the center angle of the fan shape having this arc). ) Θ ₁ is calculated by equation (2).

Expression (2) is a general expression. In Expression (2), θ represents a central angle, and C represents curvature. The distance d indicates the length of the arc. The fan-shaped center point is referred to as O ₁ . The shape estimation unit 202 uses the coordinates of the fan-shaped center point O ₁ , the coordinates of the point P ₀ , and the center angle θ ₁ as a range of the distance d centered on the curvature sensor 150-1 using Equation (3). The coordinates of the point P ₁ at the end different from the point P ₀ are calculated.

Here, P ₀ , P ₁ , and O ₁ are column vectors indicating the coordinates of the point P ₀ , the point P ₁ , and the center point O ₁ , respectively.
The coordinates of the fan-shaped center point O ₁ can be calculated from the origin O of the coordinate system, the point P _0, and the value of the curvature radius R ₁ . A center point of an arc that approximates a range of a distance d centering on the curvature sensor 150- (i + 1) adjacent to the curvature sensor 150-i (i is an integer of i ≧ 0) (a sector-shaped center point having this arc) ) The coordinates of O _{i + 1} can be calculated by equation (4).

In equation (4), O _{i + 1} , P _i , and O _i are column vectors indicating the coordinates of the center point O _{i + 1} , the point P _i , and the center point O _i , respectively. R _i and R _{i + 1} are radii of curvature determined by the equations (1) from the curvatures C _i and C _{i + 1} , respectively.
When the point at one end of the arc that approximates the range of the distance d centering on the curvature sensor 150-i is P _i−1 , the point P _{i at} the other end of the arc can be calculated by the equation (5). .

In equation (5), P _i-1 is a column vector indicating the coordinates of the point P _i-1 . In addition, θ _i indicates a central angle of a circular arc that approximates a range of a distance d centering on the curvature sensor 150-i (a central angle of a fan shape having this circular arc).

FIG. 12 is a second diagram illustrating the partial shape estimation process of the shape estimation unit.
FIG. 12 shows an example when the process shown in FIG. 11 is repeated. As described above, the shape estimation unit 202, based on the curvature the curvature sensor 0.99-i was measured C _i and the distance d (the length of the arc), calculates the coordinates of the point P _i from the point P _i-1 of the coordinates can do. In the initial processing of partial shape estimation, the point P ₀ may be coordinates arbitrarily set in the coordinate system.
The shape estimation unit 202 calculates the coordinates of the points P ₁ , P ₂ , P ₃ ,. Accordingly, the shape estimation unit 202 estimates the shape of the portion of the seat belt 1 where the curvature sensor 150 is disposed (including the portion between the curvature sensor 150 and the curvature sensor 150) by approximating the shape with a continuous arc. Can do.

  The shape estimation unit 202 estimates the shape of the portion where the curvature sensor 150 is arranged as described above by approximating the shape of the portion where the curvature sensor 150 is arranged based on information such as curvature obtained from the plurality of curvature sensors 150 provided on the seat belt 1, Thereby, the three-dimensional shape of the contact range X of the seat belt with respect to the entire seat belt 1 or the measurement target is calculated. The driver monitoring device 2 stores in advance a 3D modeling data of a plurality of three-dimensional shapes of seat belts in the chest and abdomen corresponding to different human body shapes in a storage unit such as the HDD 211. In this case, the shape estimation unit 202 compares the calculated three-dimensional shape of the entire seat belt 1, the plurality of three-dimensional shapes, and the 3D modeling data of the plurality of three-dimensional shapes of the seat belt corresponding to the human body shape. The shape estimation unit 202 identifies 3D modeling data similar to the current driver's three-dimensional shape. The shape estimation unit 202 identifies the contact range X in the seat belt 1 recorded in the storage unit in association with the identified 3D modeling data. The information of the range X of the seat belt 1 varies depending on the human body shape, and indicates the contact range X of the seat belt with respect to the measurement target when the seat belt 1 is worn according to the human body shape. Since the range of the seat belt 1 in contact with the chest and abdomen of the body varies depending on the body shape, the driver monitoring device 2 stores information on the contact range X of the seat belt when worn according to the body shape of the person. The driver monitoring device 2 may store information on the contact position X of the seat belt when the seat (seat) 4 is set according to the combination of the person's body shape and the set position of the seat (seat) 4. Then, the shape estimation unit 202 detects the current setting position of the seat 4 from a position detection device provided on the seat 4 and the like, and the seat belt recorded in the storage unit in association with the information on the installation position of the seat The 3D modeling data of a plurality of one-dimensional shapes may be acquired, and the calculated data may be compared with the calculated three-dimensional shape of the current seat belt 1.

  The shape estimation unit 202 outputs information on the contact range X in the identified seat belt 1 to the state determination unit 201. Based on the information of the contact range X, the state determination unit 201 specifies the electrode pads 12 included in the range. The state determination unit 201 determines the identified electrode pad 12 as the electrode pad 12 to be operated. The state determination unit 201 generates a tomographic image of the measurement target unit X while energizing the plurality of specified electrode pads 12 and acquiring a voltage signal generated between two of the electrode pads 12. Also good. Since the driver monitoring device 2 identifies the electrode pad 12 based on the human body shape and the set position of the seat 4, it is not necessary to energize all the electrode pads 12 provided on the seat belt. The driver monitoring device 2 has a plurality of setting positions such as the back angle of the seat 4 and the front and rear positions of the seat surface of the seat 4, and a plurality of three-dimensional positions of the seat belt 1 according to these setting positions. Shape 3D modeling data may be stored.

  Even if the state determination unit 201 specifies the curvature sensor 150 included in the range based on the information of the contact range X acquired from the shape estimation unit 202, the state determination unit 201 determines that the curvature sensor 150 operates only the curvature sensor 150. Good. According to this process, the state determination unit 201 estimates a range in which the seat belt 1 contacts the driver, and drives the electrode pad 12 or the curvature sensor 150 located in the contact range.

The state determination unit 201 may estimate a range where the seat belt 1 contacts the driver based on a voltage signal generated between the electrode pads 12. For example, the driver monitoring device 2 passes a high-frequency current between two adjacent electrode pads 12. Then, an electric field E is generated between the electrode pads 12. For example, when a body enters the electric field region, the electric field changes, and the voltage value measured by the voltmeter V changes. The driver monitoring device 2 constantly monitors the impedance change due to the influence of the measurement object such as the body in the electric field region from the fluctuation of the voltage value by the voltmeter V connected in parallel with the current source I. The impedance value can be obtained by dividing the voltage value by the current value. The driver monitoring device 2 can determine that the range of the seat belt 1 in the vicinity of the electrode pad 12 is in contact with the body when the change in impedance becomes lower than a predetermined value.
The electrode pad 12 shown in FIG. 2 may be an electrode pad 12 used only for generating a tomographic image by EIT. In this case, a plurality of electrode pads dedicated for detecting the contact range X may be periodically arranged on the substrate of the seat belt 1 at even shorter intervals.

FIG. 13 is a second view showing the internal structure of the seat belt.
In FIG. 13, the electrode pads 12 </ b> A to 12 </ b> H and the strain gauges 13 </ b> A to 13 </ b> H are omitted in order to avoid the complexity of the drawing, but actually the flexible substrate 14 is the same as in the first embodiment. Above, they are arranged in a periodic arrangement.
As shown in FIG. 13, the seat belt 1 according to the present embodiment is periodically arranged at intervals α that are shorter than the intervals P along the longitudinal direction (in parallel with the electrode pads 12 </ b> A to 12 </ b> H). The measurement range electrode pads 301, 302,..., 30f may be provided.

  The state determination unit 201 may specify the heart range and the lung range in the contact range X. For example, based on the information on the contact range X acquired from the shape estimation unit 202, the state determination unit 201 stores the heart range and lung range of the contact range X with respect to the contact range X stored in advance. It may be specified on the basis of the position information.

FIG. 14 is a diagram showing an outline of processing for specifying the contact range X.
FIG. 14A shows a state where the seat belt 1 is in contact with the measurement object.
As shown in FIG. 14A, the case where the seat belt 1 is in contact with the person who is the measurement object from the position A1 to the position A2 will be described. The seat belt 1 is close to the human body M in the contact range X from the position A1 to the position A2, and is separated from the human body M in other regions.
FIG. 14B shows in detail the vicinity of the position A1 of the seat belt 1 in the state shown in FIG. For example, it is assumed that the electrode pads 301, 302, 303, 304, 305, and 306 are arranged as shown in FIG. 14B in the vicinity of the position A1. In this case, the shape estimation unit 202 changes each electrode pad while changing the electrode pad pair in order, for example, between the electrode pads 301-302, between the electrode pads 303-302, between the electrode pads 303-304,. The electrical impedance between the pair is acquired. The electrical impedance acquired by the shape estimation unit 202 is a value depending on the electric fields E0, E1,..., E4 (FIG. 14B) generated between the electrode pad pairs.

Here, attention is focused on the paths of the electric fields E0 to E4 generated between the electrode pad pairs. As shown in FIG. 14B, the electrode pads 301a and 302 are not close to the human body M, and the electric field E0 generated therebetween is generated in the atmosphere. On the other hand, since the electrode pads 305 and 306 are close to the human body at the position A1, the electric field E4 generated therebetween passes through the human body M (in vivo). Therefore, the electrical impedance between the electrode pads 305 and 306 is measured lower than the electrical impedance between the electrode pads 301 and 302.
That is, since the electrode pads 301, 302,... Gradually approach the human body M toward the position A1, the electric fields E0, E1, E2, E3, E4 gradually pass through the human body M along the path. Since the area increases, the electrical impedance corresponding to each of the electric fields E0 to E4 gradually decreases.

  Thus, in the region where the seat belt 1 is close to the human body M, the electrical impedance between the electrode pad pairs belonging to the region is measured low, and in the region where the seat belt 1 is not close to (contact) the human body M, The electrical impedance between the electrode pad pairs belonging to the region is measured high. Therefore, the shape estimation unit 202 compares the electrical impedance with a preset threshold value, and identifies the electrode pad that constitutes between the electrode pads that can acquire the electrical impedance lower than the threshold value as the electrode pad located in the contact range X.

  The shape estimation unit 202 repeatedly detects information on the shape of the seat belt at predetermined time intervals after the start of processing. The shape estimation unit 202 detects the movement of the body such as the distance the body moves and the period based on the shape of the contact range X of the seat belt when the seat belt is worn. The shape estimation unit 202 outputs the distance and cycle of the body movement to the state determination unit 201.

The state determination unit 201 may estimate a heart rate and a ventilation amount in addition to generating a tomographic image and estimating the shape of the seat belt 1.
The state determination unit 201 generates a tomographic image of the human body corresponding to the position of the contact range X at short time intervals. The state determination unit 201 detects the movement of the shape of the lung or chest in the tomographic image by image processing, specifies the size reduction and enlargement cycle, and calculates the heart rate per unit time based on the cycle. May be. Further, the state determination unit 201 detects the movement of the shape of the lung or chest by image processing, specifies the shape change at the time of reduction or enlargement of the shape of the lung or chest, and based on the change, the ventilation volume per unit time May be calculated.

  The driver monitoring device 2 may calculate the heart rate and the ventilation volume based on the high-frequency current that flows through the electrode pad 12. The state determination unit 201 supplies a high-frequency current to the electrode pad 12. As a result, the state determination unit 201 can detect an impedance change caused by air entering and exiting the lungs due to breathing based on the input signal from the voltmeter V. More specifically, since the impedance of air is high, when the amount of air flowing into the lung decreases (corresponding to the amount of ventilation exhaled), the lung impedance value decreases accordingly. Therefore, when the lung is expanded, the air amount increases (corresponding to the amount of ventilation to be inhaled), and the state determination unit 201 detects that the impedance value has increased. On the other hand, when the lung contracts and air flows out of the lung, the state determination unit 201 detects that the impedance has changed in the lower direction. Thus, the measurement of the lung ventilation can be performed by the driver monitoring device 2.

  In addition, the blood volume in the heart changes due to the heartbeat. The state determination unit 201 supplies a high-frequency current to the electrode pad 12. As a result, the state determination unit 201 can detect a change in impedance caused by the increase or decrease in the blood volume in the heart accompanying the heartbeat based on the input signal from the voltmeter V. More specifically, since the impedance of blood is low, the impedance of the heart increases as the blood volume of the heart decreases. Therefore, when the heart contracts, the state determination unit 201 detects that the impedance has changed in the higher direction. On the other hand, when the heart expands and blood flows into the heart, the state determination unit 201 detects that the impedance has changed in the lower direction. Thus, the heart rate information of the heart can be measured by the driver monitoring device 2.

  In addition, since the driver monitoring device 2 directly detects an increase or decrease in blood volume in the heart based on an impedance change, it can detect heartbeat information with higher accuracy than in the past. For example, the state determination unit 201 detects the heart rate per unit time based on the number of peak values per unit time based on the impedance change.

  In the measurement of the ventilation amount described above, the voltmeter V measures the voltage and outputs it to the state determination unit 201. The state determination unit 201 calculates an impedance value based on the voltage measurement result of the voltmeter V. And the state determination part 201 determines the change from the impedance value in a stable state. The state determination unit 201 converts the impedance change amount into a ventilation amount based on the impedance change amount and the correction formula, correction table, or the like. The state determination unit 201 repeatedly calculates the ventilation volume at short time intervals (for example, every several milliseconds). And the state determination part 201 records the ventilation volume of each time in memory according to time progress.

In the above heartbeat measurement, the voltmeter V measures the voltage and outputs it to the state determination unit 201. Then, the state determination unit 201 calculates an impedance value based on the voltage measurement result of the voltmeter V. The state determination unit 201 repeatedly calculates the impedance value at a short time interval (for example, every several milliseconds). The state determination unit 201 records the amount of change in impedance at each time in the memory as time elapses. The state determination unit 201 calculates the heart rate per unit time based on the number of peak values per unit time based on the impedance change, and records it in the memory. Through the above processing, heart rate information at each time corresponding to the passage of time is accumulated in the memory.
The state determination unit 201 performs control so as to switch between ventilation volume acquisition and heart rate acquisition processing. Alternatively, in a case where the heart range and the lung range with respect to the contact range X can be specified, the state determination unit 201 acquires the ventilation amount from the signal of the electrode pad 12 located in the lung range, and the electrode pad 12 located in the heart range. You may make it acquire a heart rate from the signal of.

  The state determination unit 201 determines normality or abnormality of the driver's state using one or more of the shape of the seat belt 1, the tomographic image, the heart rate, and the ventilation. The shape of the seat belt 1 that the state determination unit 201 uses for the driver's state may be the shape of the contact range X. Alternatively, the state determination unit 201 uses only the curvature data from the curvature sensor 150 provided on the seat belt 1 when using the state of the driver, and the movement of the driver, the heart rate, and the ventilation amount. The normal or abnormal state of the driver may be determined using any one or a plurality. The movement of the body is, for example, a movement of the body that repeats the movement of the driver's body facing the handle approaching the handle or moving away from the handle. The state determination unit 201 determines the movement of the body using the conversion of the value of curvature data at predetermined intervals of the curvature sensor 150. The state determination unit 201 estimates the body movement, the heart rate, and the ventilation amount only by the change in the shape of the seat belt 1, thereby giving an electrical signal to the chest also for the driver who holds the heart rate pacemaker in the body. The state of the driver can be determined without any problem.

The state determination unit 201 may determine whether the driver feels drowsy based on the distance, period, and body movement pattern of the body determined based on the shape of the seat belt.
Further, the state determination unit 201 may detect a breathing interval and a ventilation amount based on a change in a lung region obtained by image processing of a tomographic image. The state determination unit 201 determines whether the breathing interval and the ventilation volume have increased or decreased from the detected breathing interval and the ventilation volume during the initial period of driving, or the driver's sleepiness and Other physical conditions may be determined.
Further, the state determination unit 201 detects the heart rate per unit time obtained by the image processing of the tomographic image. The state determination unit 201 determines whether the heart rate of the driver has increased or decreased than the heart rate detected during the initial period of driving, or the pattern of repeated increase and decrease, and the driver's sleepiness and other physical conditions. The state may be determined.
In addition, the state determination unit 201 may determine the drowsiness of the driver and other physical conditions by combining a breathing interval and a pattern of increase or decrease in heart rate.
The state determination unit 201 may use a known technique in determining the driver's state using the heart rate, the ventilation amount, the body movement, and the breathing interval.

FIG. 15 is a first diagram illustrating a processing flow of the driver monitoring apparatus.
The shape estimation unit 202 of the driver monitoring device 2 acquires curvature data from the curvature sensor 150 (step S101). The shape estimation unit 202 determines the shape of the seat belt from the curvature data (step S102). The shape estimation unit 202 outputs information indicating the shape of the seat belt to the state determination unit 201. The information indicating the shape of the seat belt 1 may be 3D modeling data of the shape, or may be the curvature value itself obtained from each curvature sensor 150. The state determination unit 201 calculates state information such as body movement, breathing interval, and ventilation volume from information indicating the shape of the seat belt 1 (step S103). The state determination unit 201 determines whether the driver's state is bad by using one or more of the state information (step S104). The state determination unit 201 outputs warning information when determining that the driver's state is bad (step S105). The warning information is a signal that sounds an alarm that is a warning sensor. The state determination unit 201 may emit a warning by vibrating a vibration device that is a warning sensor provided in a seat and a handle.
When the driver monitoring device 2 performs the process shown in FIG. 15, the seat belt 1 may be provided with a plurality of curvature sensors 150 even though the electrode pad 12 is not provided.

FIG. 16 is a second diagram illustrating a processing flow of the driver monitoring apparatus.
The shape estimation unit 202 of the driver monitoring device 2 acquires an electrical signal from the electrode pad 12 (step S201). The state determination unit 201 generates a tomographic image using the above-described EIT technique (step S202). The state determination unit 201 uses the tomographic image to calculate state information such as a breathing interval, a ventilation amount, and a heartbeat based on a change in the image with time (step S203). The state determination unit 201 determines whether the driver's state is bad using one or more of the state information (step S204). If the state determination unit 201 determines that the driver is in a bad state, the state determination unit 201 outputs warning information (step S205). The warning information may be an alarm sound. The state determination unit 201 may issue a warning by vibrating a vibration device provided in the seat and the handle. The warning information may be a control signal for a control device such as an automatic brake. Thus, by outputting the alarm information to the device that controls the vehicle, more active danger avoidance control may be performed in combination with an automatic steering (automatic driving) technique or the like.
When the driver monitoring device 2 performs the process shown in FIG. 16, the seat belt 1 may be provided with a plurality of electrode pads 12 even though the curvature sensor 150 is not provided.

FIG. 17 is a third diagram illustrating a processing flow of the driver monitoring apparatus.
The shape estimation unit 202 of the driver monitoring device 2 acquires curvature data from the curvature sensor 150 (step S301). The shape estimation unit 202 determines the shape of the seat belt 1 from the curvature data (step S302). The shape estimation unit 202 outputs information indicating the shape of the seat belt 1 to the state determination unit 201. The information indicating the shape of the seat belt 1 may be 3D modeling data of the shape, or may be the curvature value itself obtained from each curvature sensor 150. The state determination unit 201 calculates state information based on the shape of the seat belt 1 such as body movement, breathing interval, and ventilation volume from information indicating the shape of the seat belt 1 (step S303).

  The shape estimation unit 202 of the driver monitoring device 2 acquires an electrical signal from the electrode pad 12 (step S304). The state determination unit 201 generates a tomographic image using the EIT technique described above (step S305). The state determination unit 201 uses the tomographic image to calculate state information such as a breathing interval, a ventilation amount, and a heartbeat based on a change in the image with time (step S306). The state determination unit 201 determines whether the driver is in a bad state using one or more of the state information calculated in step S303 and the state information calculated in step S306 (step S307). The subsequent processing is the same as the processing shown in FIGS. If the state determination unit 201 determines that the driver's state is bad, it outputs warning information (step S308).

FIG. 18 is a fourth diagram showing a processing flow of the driver monitoring apparatus.
The shape estimation unit 202 of the driver monitoring device 2 acquires curvature data from the curvature sensor 150 (step S401). The shape estimation unit 202 determines the shape of the seat belt 1 from the curvature data (step S402). The shape estimation unit 202 outputs information indicating the shape of the seat belt to the state determination unit 201. The information indicating the shape of the seat belt 1 may be 3D modeling data of the shape, or may be the curvature value itself obtained from each curvature sensor 150. The shape estimation unit 202 identifies the contact range X based on the shape of the seat belt (step S403), and outputs information on the range to the state determination unit 201. Based on the contact range X, the state determination unit 201 determines to operate the electrode pad 12 and the curvature sensor 150 located in the range, and determines to energize (step S404). Thereafter, the state determination unit 201 and the shape estimation unit 202 receive signals from the electrode pads 12 and the curvature sensor 150 that are determined to be energized.

The shape estimation unit 202 determines the shape of the seat belt based on the curvature data acquired from the operating curvature sensor 150 (step S405). The state determination unit 201 determines the body movement and breathing interval from the information indicating the shape of the seat belt 1. Then, state information such as ventilation volume is calculated (step S406). The shape estimation unit 202 acquires an electrical signal from the electrode pad 12 (step S407). The state determination unit 201 generates a tomographic image using the above-described EIT technique (step S408). The state determination unit 201 uses the tomographic image to calculate state information such as a breathing interval, a ventilation amount, and a heartbeat based on a change in the image over time (step S409). The state determination unit 201 determines whether the driver is in a bad state using one or more of the state information calculated in step S406 and the state information calculated in step S409 (step S410). The state determination unit 201 outputs warning information when it is determined that the driver's state is bad (step S411).
Note that the processing flows shown in FIGS. 15 to 17 do not include the process of specifying the contact range X, but may include the process of specifying the contact range X. Further, the processing flows shown in FIGS. 15 to 18 may include the processes described in the above paragraphs 0083 to 0087.
According to the processing of the driver monitoring device described above, it is possible to detect the state of the driver's body and issue a warning to the driver, or to use it for control assisting the driving operation. The control for assisting the driving operation may be brake control such as automatic deceleration.
Moreover, according to the above-described driver monitoring device, it is possible to easily determine a health condition abnormality during driving by a driver without a special device.

FIG. 19 is a second diagram illustrating a functional configuration of the driver monitoring apparatus according to the first embodiment.
The driver monitoring device 2 may further have functions of a recording unit 203, a display processing unit 204, and a correction unit 205 by executing a program.
The recording unit 203 records one or more of a tomographic image, a heart rate, a ventilation state, and other driver states in the HDD 211. By the processing of the recording unit, it is possible to grasp the state of the body and consciousness during the past driving of the driver.
The display processing unit 204 displays any one or a plurality of information of a tomographic image, a heart rate, a ventilation state, and other driver states on a monitor such as the image display unit 123.
The correction unit 205 corrects the value output from the curvature sensor based on the shape of the seat belt 1 when the seat belt 1 is in a predetermined state where the seat belt 1 is not used. For example, a situation where the seat belt 1 is not used is detected by some detection function. When the seat belt 1 is not used, for example, the output of the curvature sensor 150 in the seat belt 1 is a predetermined value. If the value of the curvature sensor 150 is not a predetermined value when the seat belt 1 is not used, the difference between the predetermined value and the currently acquired value is used as a correction value.

The above-described seat belt 1 may have a mechanism that can be removed from the vehicle body. When an accident occurs, an ambulance crew member removes the seat belt 1 from the vehicle body, winds it around the passenger, and operates the seat belt 1 and the driver monitoring device 2. And you may make it monitor the state of the passenger of the car which the accident generate | occur | produced by the process of 1st embodiment. In this case, the seat belt 1 and the driver monitoring device 2 may have a function capable of communication connection via wireless communication. Further, the seat belt 1 has a function capable of wirelessly communicating with a mobile terminal, and the mobile terminal may have a function of a driver monitoring device. In this case, each signal received from the seat belt 1 is processed, and the portable terminal performs the above-described processing equivalent to the driver monitoring device. Thereby, the state of the passenger in the car can be monitored by the portable terminal.
Since the internal structure of the seat belt 1 is composed of the flexible substrate 14 on which the circuit pattern is printed, the seat belt can be wound around the human body as described above to monitor the state of the subject.
The seat belt 1 and the driver monitoring device 2 described above may be mounted on a moving body on which various persons to be measured such as cars and airplanes board.

<Second Embodiment>
FIG. 20 is a diagram illustrating a monitoring device and a restraining belt according to the second embodiment.
In the above description, the driver monitoring device 2 that detects the state of the driver using the seat belt 1 is described. However, the restraint belt 7 having the same function as the function of the seat belt 1 described in the first embodiment, and the monitoring device 6 having the same function as the function of the driver monitoring apparatus 2 described in the first embodiment, The monitoring device 6 may monitor the state of the person being measured using For example, the restraining belt 7 is attached to the bed 5. FIG. 20 shows a connection relationship between the top view of the bed 5 and the monitoring device 6. The patient lying on the bed 5 may be fixed with the restraint belt 7, and the monitoring device 6 may acquire the patient's body movement, breathing interval, ventilation volume, heart rate, tomographic image, etc. while lying down.
The operation of the monitoring device 6 is the same as the operation according to the processing flow shown in FIGS.
According to the monitoring device described above, the state of the person to be measured can be easily measured by the belt.

In addition, the electrode pad 12 and the curvature sensor 150 etc. which are equivalent to the suppression belt 7 are periodically arranged on the bed 5 shown in FIG. You may make it monitor by the method similar to.
In this case, a bed or a mat of the bed 5 includes a plurality of electrode pads 12 and a plurality of curvature sensors 150. The monitoring device is electrically connected to the electrode pad 12 and the curvature sensor 150 provided on the sheet or mat. Then, the monitoring device estimates the deformation of the sheet or mat based on the curvature data acquired via the curvature sensor 150. For example, the change in the shape of the sheet or mat may be a change in the shape of the surface of the sheet or mat due to a change in the force applied to the sheet or mat when the subject moves the body. Alternatively, the change in the shape of the sheet or mat may be a change in the shape of the surface of the minute sheet or mat based on the breathing or beating of the measurement subject. The monitoring device determines the state of the person to be measured based on the deformed shape of the sheet or mat. The monitoring device calculates one or more state information of the tomographic image, heart rate, and ventilation state of the person to be measured based on the electric signal obtained from the electrode pad 12 provided on the sheet or mat, and The state information is used to determine whether the subject is normal or abnormal.

<Third Embodiment>
In the third embodiment, the electrode pad 12 and the curvature sensor 150 are periodically arranged on the sheet 4 shown in FIG. 4, and the state of the subject is determined from the signals from the electrode pad 12 and the curvature sensor 150. You may make it monitor by the method similar to.
In this case, the sheet 4 includes a plurality of electrode pads 12 and a plurality of curvature sensors 150. The monitoring device is electrically connected to the electrode pad 12 and the curvature sensor 150 provided on the sheet 4. The monitoring device estimates deformation of the seat 4 based on the curvature data acquired via the curvature sensor 150. For example, the change in the shape of the seat 4 may be a change in the shape of the backrest surface due to a change in the force with which the driver leans against the backrest. Alternatively, the change in the shape of the seat 4 may be a change in the shape of the backrest surface due to the action of the driver bringing the body into close contact with or away from the backrest. Alternatively, the change in the shape of the seat 4 may be a change in the shape of the minute backrest surface based on the breathing and beating of the driver. Then, the monitoring device determines the state of the subject based on the deformed shape of the seat 4. The monitoring device calculates one or more state information of a tomographic image, heart rate, and ventilation state of the person to be measured based on the electrical signal obtained from the electrode pad 12 provided on the seat 4, and the state The information is used to determine whether the measurement subject is normal or abnormal.

  The seat belt 1, the seat 4, the bed 5, the sheets, the mat, and the like described in the above embodiments are examples of the body contact member.

  The driver monitoring device 2 and the monitoring device 6 described above have a computer system inside. Each process described above is stored in a computer-readable recording medium in the form of a program, and the above process is performed by the computer reading and executing the program. Here, the computer-readable recording medium means a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like. Alternatively, the computer program may be distributed to the computer via a communication line, and the computer that has received the distribution may execute the program.

  The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

DESCRIPTION OF SYMBOLS 1 ... Seat belt 2 ... Driver monitoring device 3 ... Communication cable 4 ... Seat 5 ... Bed 6 ... Monitoring device 7 ... Suppression belt 11 ... Measurement circuit 12 ... Electrode pad 114 ... Serial communication circuit 150 ... Curvature sensor 156 ... Amplifier 157 ... A / D converter 181... Signal conversion module

Claims (19)

Electrically connected to the curvature sensor of the seat belt provided with a plurality of curvature sensors;
A shape estimation unit that estimates the shape of the seat belt based on curvature data acquired via the curvature sensor;
A state determination unit that determines the state of the driver based on the shape of the seat belt;
A driver monitoring device comprising: The driver monitoring apparatus according to claim 1, wherein the state determination unit estimates a range in which the seat belt contacts the driver and drives the curvature sensor positioned in the contact range. The state determination unit
The driver according to claim 1, wherein normality or abnormality of the driver's condition is determined using any one or more of the shape of the seat belt, heart rate, and ventilation state. Monitoring device. The seat belt is electrically connected to the electrode of the seat belt provided with a plurality of electrodes,
The state determination unit
On the basis of energization to the plurality of electrodes and a voltage signal generated between the electrodes, a tomographic image of the driver in a range where the seat belt contacts the driver is generated, and based on the tomographic image The driver monitoring apparatus according to claim 3, wherein a state of the driver is determined. The state determination unit
The driver monitoring apparatus according to claim 4, wherein the heart rate of the driver is detected based on energization to the plurality of electrodes and a voltage signal generated between the electrodes. The state determination unit
6. The ventilation state of the driver is detected based on energization to the plurality of electrodes and a voltage signal generated between the electrodes. 6. The driver monitoring device described. A recording unit that records one or more of the tomographic image, the heart rate, the ventilation state, and the driver state;
The driver monitoring device according to any one of claims 4 to 6, further comprising: A display processing unit for displaying on the monitor one or more of the tomographic image, the heart rate, the ventilation state, and the driver state;
The driver monitoring device according to any one of claims 4 to 7, further comprising: The driver monitoring apparatus according to any one of claims 1 to 8, wherein the state determination unit operates a warning sensor when it is determined that the state of the driver is abnormal. A correction unit that corrects the output information of the curvature sensor based on the shape of the seat belt when the seat belt is in a predetermined state that is not used;
The driver monitoring device according to any one of claims 1 to 9, further comprising: Electrically connected to the electrode of the seat belt provided with a plurality of electrodes,
Based on energization to the plurality of electrodes and a voltage signal generated between the electrodes, a tomographic image of the driver in a range where the seat belt contacts the driver is generated, and driving based on the tomographic image is performed. A state determination unit for determining the state of the hand;
A driver monitoring device comprising: Connected to a body contact member provided with a plurality of electrodes,
Based on the electrical signals obtained from the electrodes, calculate one or more state information of a tomographic image, heart rate, and ventilation state of the subject, and use the state information to determine the state of the subject. A state determination unit for determining normality or abnormality;
A monitoring device comprising: Connected to a body contact member provided with a plurality of curvature sensors;
Based on the signal obtained from the curvature sensor, one or a plurality of state information of the body movement, heart rate, and ventilation state of the measurement subject is calculated, and the state of the measurement subject is calculated using the state information. A state determination unit for determining;
A monitoring device comprising: A monitoring device connected to a body contact member provided with a plurality of electrodes,
Based on the electrical signals obtained from the electrodes, calculate one or more state information of a tomographic image, heart rate, and ventilation state of the subject, and use the state information to determine the state of the subject. A monitoring method for determining whether normal or abnormal. A monitoring device connected to a body contact member provided with a plurality of curvature sensors,
Based on the signal obtained from the curvature sensor, one or a plurality of state information of the body movement, heart rate, and ventilation state of the measurement subject is calculated, and the state of the measurement subject is calculated using the state information. The monitoring method to judge. A monitoring computer connected to a body contact member provided with a plurality of electrodes,
Based on the electrical signals obtained from the electrodes, calculate one or more state information of a tomographic image, heart rate, and ventilation state of the subject, and use the state information to determine the state of the subject. A program characterized by functioning as state determination means for determining normality or abnormality. A computer of a monitoring device connected to a body contact member provided with a plurality of curvature sensors;
Based on the signal obtained from the curvature sensor, one or a plurality of state information of the body movement, heart rate, and ventilation state of the measurement subject is calculated, and the state of the measurement subject is calculated using the state information. A program that functions as a state determination means for determination. A plurality of electrodes periodically arranged;
A plurality of curvature sensors periodically arranged in parallel with the plurality of electrodes;
A seat belt comprising: An output unit that detects the use of the seat belt and outputs a use detection signal to the driver monitoring device;
The seat belt according to claim 18, further comprising: