JP2004113329A - Pillow type sleep measuring instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately detect biological signals to monitor a subject's sleep and provide an examinee with a comfortable sleeping environment. <P>SOLUTION: The subject sleep measuring instrument is a pillow type, monitors the subject's sleep and determines the subject's sleeping condition on the basis of measurement data and deforms the pillow into an appropriate shape so as to help the subject obtain a comfortable sleep. An appropriate detection of biological signals measured is constantly confirmed to precisely determine the sleep. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a device for measuring sleep.
[0002]
[Prior art]
For example, there is a device that simply monitors sleep by laying an air mat under the body of a subject, calculating body movement and pulse from measured signals, and monitoring sleep by correlation with a sleep stage based on brain waves. Was.
[0003]
Specifically, a pillow that determines whether REM sleep or non-REM sleep based on the depth of sleep during sleep has been proposed (for example, see Patent Document 1).
[0004]
A pillow for detecting respiration has also been proposed (for example, see Patent Document 2).
[0005]
On the other hand, there is a device that can adjust the height of the pillow to a desired height by changing the air pressure inside the pillow so that the user can sleep comfortably (for example, see Patent Reference 3)
[0006]
Furthermore, there is a device that determines the orientation of the body during sleep, such as when lying supine or lying down, and automatically changes the height of the pillow (for example, see Patent Document 4).
[0007]
[Patent Document 1]
JP-A-4-256732 [Patent Document 2]
JP 2002-119496 A [Patent Document 3]
Japanese Patent Application Laid-Open No. 2002-65433 [Patent Document 4]
JP 2001-340198 A
[Problems to be solved by the invention]
The larger the area of the air mat, the better it can catch the signal even if the air is turned over, but it is inconvenient to carry. On the other hand, if the area of the air mat is large, on the contrary, unnecessary signals such as ambient vibrations are picked up, and it is difficult to separate and detect signals such as a pulse of a living body from the detected signals. In particular, the detection of a biological signal by the air mat changes greatly depending on the sleeping state, and the signal level greatly differs between when sleeping with the heart down and when sleeping with the signal up.
[0009]
Also, since the vibration noise of the building is relatively close to the frequency of the signal emitted by the living body, it is difficult to separate it by filtering, and even if the signal from the living body is small, even if the signal is greatly amplified using auto gain control, the signal will not In some cases, the signal cannot be measured because it is buried in noise.
[0010]
Also, regarding the pillow itself, it is said that providing a comfortable sleep by changing the height of the pillow between the time of lying on the back and the time of lying down, but it is decided only by the posture of the body at the time of sleep, The height does not change in consideration of the depth of sleep and other information, that is, while measuring the sleep state, it did not reach the point where a more comfortable environment was created.
[0011]
In addition, the pillow that determines whether the sleep is REM sleep or non-REM sleep can simply discriminate between them, and it is useful for the user himself to set the wake-up time.
[0012]
The present invention has been made in view of such a problem, and has a configuration in which a biological signal is detected with high accuracy in order to monitor the sleep of a subject, and to provide a more comfortable sleep environment to the subject. .
[0013]
[Means for Solving the Problems]
Pillow-type sleep measurement device of the present invention, pillow height setting means to set the height of the pillow,
Biological signal detecting means for detecting a biological signal,
The pillow height setting means is controlled based on the detected biological signal and determines the sleep comfort of the subject based on the sleep comfort of the subject determined by the determination means.
[0014]
Further, the pillow-type sleep measuring device of the present invention, a pillow height setting means for setting the height of the pillow,
Biological signal detecting means for detecting a biological signal,
Determining an index based on the autonomic nervous system from the detected biological signal, determining means for determining the comfort of the subject's sleep from the calculated index,
Control means for controlling the pillow height setting means based on the sleep comfort of the subject determined by the determination means.
[0015]
Further, the pillow-type sleep measuring device of the present invention, a pillow height setting means for setting the height of the pillow,
Biological signal detecting means for detecting a biological signal,
From the detected biological signal, calculate an index based on the sleep depth and the autonomic nervous system, determining means for determining the comfort of the subject's sleep from the current sleep depth and the calculated index,
Control means for controlling the pillow height setting means based on the sleep comfort of the subject determined by the determination means.
[0016]
Further, in the pillow-type sleep measuring device of the present invention, the pillow height setting means can set the heights of a plurality of places of the pillow.
[0017]
In the pillow-type sleep measuring device of the present invention, the biological signal detected by the biological signal detecting means is related to a heart rate.
[0018]
In the pillow-type sleep measuring device of the present invention, the biological signal detected by the biological signal detecting means is related to respiration.
[0019]
Further, in the pillow-type sleep measuring device of the present invention, the biological signal detected by the biological signal detecting means is related to body movement.
[0020]
Further, in the pillow-type sleep measuring device of the present invention, the determining means calculates the activity of the sympathetic nerve and the activity of the parasympathetic nerve from the pulse wave signal detected by the biological signal detecting means, and calculates the index of the autonomic nerve. Uses the activity of the sympathetic nerve and the activity of the parasympathetic nerve.
[0021]
In the pillow-type sleep measuring device of the present invention, the activity of the sympathetic nerve and the activity of the parasympathetic nerve from the pulse wave signal in the determination means are calculated by performing time-frequency analysis of the pulse.
[0022]
Further, the pillow-type sleep measurement device of the present invention, the pillow height setting means is provided so as to be able to set the height of at least two places in front and back of the pillow,
The biological signal detected by the detection means is related to snoring,
The determining means determines whether snoring has occurred,
The control means lowers the front of the pillow and increases the depth of the pillow when snoring occurs.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
[0024]
The sleep measuring device of the present invention is a pillow type, monitors the sleep of the subject, determines the sleep state of the subject based on the measurement data, and sets the pillow appropriately so that the subject can get a comfortable sleep. Deform to shape. In addition, it is configured to always check whether or not the biological signal being measured is properly detected, so that the sleep can be determined with high accuracy.
In addition, a comfortable sleep environment is provided by evaluating the sleep state of the subject and changing the shape of the pillow in real time. As an evaluation of the sleep state, an index based on the autonomic nervous system is used. Specifically, whether the sleep is comfortable is determined based on the activities of the sympathetic nerve and the parasympathetic nerve, and the height of the pillow is controlled. In addition, if the determination of the activity levels of the sympathetic nerve and the parasympathetic nerve is made in accordance with the depth of sleep (sleep stage) of the subject, more accurate determination of sleep comfort can be made.
[0025]
【Example】
An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is an external view of the sleep measuring device of the present invention.
The sleep measuring device comprises a pillow 1 and an operation box 2, which are connected by a cord 3. The operation box 2 includes a switch unit 4 as an input unit including a plurality of switches such as a power switch, a high switch, a low switch, a start switch, and a stop switch, and an LCD 5 as a display unit for displaying various information.
[0026]
FIG. 2 is a block diagram of the present sleep measuring device.
Inside the pillow 1, an air-filled bag 6 for forming the shape of the pillow is provided, and an air pressure adjusting device (actuator) 7 for flowing air into and out of the air-filled bag 6 is provided. By changing the air pressure, the height of the pillow is changed.
[0027]
The sensor 8 for detecting a signal of a living body includes an air mat and a condenser microphone for detecting an air pressure in the air mat.
[0028]
The operation box 2 amplifies a signal from the pressure sensor 8 by a microcomputer (CPU) 10 which is an arithmetic control means for performing various calculations and control of various units, in addition to the switch unit 4 and the LCD 5, and a gain signal control from the microcomputer 10. An input amplifier 11, a low-pass filter (LPF) 12 through which a signal component of respiration of 0.8 Hz or less passes, a band-pass filter (BPF) 13 through which a signal component of a heartbeat waveform of 0.8 to 10 Hz passes, body movement of 10 Hz or more A high-pass filter (HPF) 14 through which snoring signal components pass is provided. Each filter circuit is connected to a body movement amplifier 15, a heartbeat amplifier 16, and a respiration amplifier 17, and each amplifier is connected to an A / D converter 18 that converts an analog signal into a digital signal. The A / D converter 18 controls a signal to be converted among the three types of biological signals by a control signal from the microcomputer 10, and a digital signal that is an output signal from the A / D converter 18 is input to the microcomputer 10.
[0029]
Also, an EEPROM 19 as a storage means and a buzzer 20 for notifying by sound at a set time are connected to the CPU 10.
[0030]
FIG. 3 is an internal cross-sectional view of the pillow 1 in the front-rear direction. As shown here, the airbag 6a provided on the front side (front) and the airbag 6b provided on the rear side (back) are used. Become. These air bladders 6a and 6b are provided in the lateral direction independently of each other and are connected to the actuator 7, respectively, and can be expanded and contracted.
[0031]
Above the air bladders 6a and 6b, an air mat which is a sensor for detecting a biological signal is provided from the front to the rear.
[0032]
Next, the operation of the sleep measuring device 1 of the present invention will be described with reference to the flowcharts shown in FIGS.
[0033]
When the user of the sleep measuring device 1 serving as a subject turns on the power switch before going to bed, the device is driven.
[0034]
The CPU 10 reads the default value of the pillow height from the EEPROM 19 (step S1), and sets the pillow height based on the read value. That is, the air bags 6a and 6b are adjusted (step S2).
[0035]
Here, since an instruction to set the wake-up time is displayed on the LCD 5, the user sets the time to wake up using the switch 4 (step S3). As the wake-up time, the time set last time is called as an initial value.
[0036]
Furthermore, since the content asking whether the pillow height is good is displayed on the LCD 5, the user can adjust the pillow height. In the present invention, the adjustment of the pillow height is to change the air pressure of the air bags 6a and 6b provided inside the pillow. When air is injected by the actuator 7, the air pressure increases and the pillow height also increases. . Conversely, when air is evacuated, the air pressure drops and the pillow height decreases.
[0037]
When the high switch of the switches 4 is pressed (step S4), the pillow height is increased by one step from the current set value (step S5). When the low switch is pressed (step S6), the pillow height is lowered by one step from the current set value (step S7).
[0038]
Until the start switch is pressed, the pillow height can be set (step S8). Here, the user may be in a sleeping posture.
[0039]
When the start switch is pressed, the CPU 10 reads the reference gain of the input amplifier 11 from the EEPROM 19 (Step S9). Here, the gain setting value is set to a default value (step S10). Further, the average value LFs of the low frequency component of the pulse wave and the average value As of the high frequency component of the pulse wave in each of the sleep stages 1 to 4 are read (step S11).
[0040]
After that, the measurement mode is set (step S12). The measurement mode will be described later.
[0041]
Further, an autonomic nerve index calculation mode is set (step S13). The autonomic nerve index calculation mode will be described later.
[0042]
It is determined whether or not the wake-up time set in step S3 has come, and the measurement mode and the autonomic nerve index calculation mode are repeated until the wake-up time comes (step S14).
[0043]
When the wake-up time has come, the buzzer 20 sounds (step S15) and continues to sound until the stop switch is pressed (step S16).
[0044]
Thereafter, the appearance rate of each sleep stage is displayed on the LCD 5 as a result measured during the current sleep (step S17). When the stop switch is pressed again, the display on the LCD 5 is turned off (step S18), and the LFs and As data in each sleep stage obtained by the current measurement are stored in the EEPROM 19 (step S19), and all the operations are ended. It becomes.
[0045]
In the measurement mode, the biological signal obtained from the sensor 8 is separated and analyzed, and various calculations are performed to determine the current depth of sleep (sleep stage).
[0046]
The biological signal from the sensor 8 is amplified by the input amplifier 11 based on the gain control signal from the CPU 10 and is input to each of the filter circuits 12, 13, and 14.
[0047]
The biological signal obtained via the HPF 12 and the body movement signal amplifier 15 is converted from an analog signal to a digital signal by the A / D converter 18 (step S21), and the current body movement level is calculated (step S22).
[0048]
It is determined whether the value calculated here is within the body motion threshold (step S23). If the body movement level exceeds the body movement threshold, it is determined that the user is still in the awake state and is not in a state where measurement during sleep is performed, and other heartbeats and breathing are not calculated.
[0049]
When the body motion level is equal to or lower than the threshold and it is determined that the subject is in a sleep state, the heart rate is calculated from the pulse wave signal. The A / D converter 18 converts the pulse wave biological signal obtained via the BPF 13 and the heartbeat signal amplifier 16 from an analog signal to a digital signal (step S24). The channel of the A / D converter is controlled by the CPU 10.
[0050]
At this time, it is determined whether or not the signal amplitude of the pulse wave exceeds a threshold required as required pulse rate data (step S25). Here, if it is equal to or smaller than the threshold value, the signal amplitude is small, so that the CPU 10 controls to increase the gain of the input amplifier 11 (step S26).
[0051]
In addition, it is determined whether or not the pulse wave signal amplitude has overflowed (step S27). If the signal overflows, the signal amplitude is large, so that the CPU 10 controls to reduce the gain of the input amplifier 11 (step S28).
[0052]
When the signal amplitude is determined to be in the normal range in steps S25 and S27, the current pulse rate is calculated. In the present invention, the calculated pulse rate = heart rate (step S29).
[0053]
Next, the respiration rate is calculated. The respiratory biological information obtained via the LPF 14 and the respiratory amplifier 17 is converted from an analog signal to a digital signal by the A / D converter 18 (step S30), and the current respiratory rate is calculated (step S31).
[0054]
Next, snoring is detected. Since the signal component of snoring is set to 100 Hz or more, a body motion signal using an HPF is used. The signal frequency of snoring is higher than that of sudden body movement, and it is possible to determine the snoring level. The snoring level is calculated (step S32). Whether or not the snoring level is high is compared with a snoring threshold (step S33).
[0055]
Here, when it is determined that snoring has occurred, the height of the front air bag 6a is lowered by bleeding air, and the height of the rear air bag 6b is increased by injecting air. When the height of the pillow is changed in this manner, the user's head is raised and the chin is lowered. As a result, the airway of the user is secured, and snoring is eliminated (step S34).
[0056]
The data of the calculated body motion level, heart rate, and respiratory rate are stored in the RAM in the microcomputer 10 (step S35).
[0057]
Next, the sleep stage / sleep stage is calculated.
[0058]
Generally, the sleep stage of a human fluctuates along a cycle called ultradian rhythm, and repeats a deep sleep (non-REM sleep) and a light sleep (REM sleep) periodically, which is known to be a cycle of about 90 minutes. Have been. Non-REM sleep is further divided into stages 1 to 4 according to the depth of sleep (stage 1 is shallower and stage 4 is deeper), but the appearance rate of each sleep stage is stage1 = 8.4% and stage2 in adults. = 48%, stage3 + 4 = 18.4%, and REM = 25.2%. Here, the cycle and the appearance rate of the sleep stage change with age, and the older the person becomes, the shallower the sleep becomes, thereby the poorer the periodicity becomes (out of the 90 minute cycle).
[0059]
In the present embodiment, the fluctuation cycle (pattern) of the sleep stage and the appearance rate of each sleep stage are calculated from the change in the pulse rate during sleep. That is, it is determined at which stage sleep is at stage 1, 2, 3 + 4 or REM. Immediately after sleep, stage 4 of deep sleep often occurs, and thereafter, in the transition period to another stage, a slight unstable period of the pulse occurs, and at the time of the next stage, a stable pulse wave rate and Become. When the pulse rate increases, the stage decreases, and when the pulse rate decreases, the stage increases. It should be noted that when the pulse rate rises from the stage 1 pulse rate, the state is a REM sleep state, and when the pulse rate falls from the REM sleep pulse rate, the state has shifted to the stage 1.
[0060]
In this manner, the transition from the stable pulse rate state to another stable pulse rate state is used to determine the transition of the sleep stage.
[0061]
The respiratory rate and body movement level are also used for determining REM sleep and other sleep stages. In REM sleep, the respiratory rate is higher and the frequency of body movements is higher than in other stages 1 to 4, and it is possible to determine whether the sleep is REM sleep or not (step S36).
[0062]
Thus, the measurement mode ends.
[0063]
In the autonomic nervous index calculation mode, it is determined whether or not the subject is getting comfortable sleep according to the activity of the sympathetic nerve and the activity of the parasympathetic nerve.
[0064]
Sympathetic nerves are implicated in muscle tone, and parasympathetic nerves are implicated in mental relaxation.
[0065]
When a person is sleeping comfortably, the person becomes mentally relaxed, the parasympathetic nervous activity increases, and the sympathetic nervous activity decreases. Conversely, if the pillow height does not suit you, you will not sleep well and you have a burden on one of your bodies, or if you have an uncomfortable sleep such as having a bad dream, muscle tension It is said that the degree increases, the parasympathetic nervous activity decreases, and the sympathetic nervous activity increases. In the present invention, this change is captured, and when comfortable sleep is obtained, the state is maintained as it is, and in an uncomfortable sleep state, the pillow height is adjusted so as to shift to comfortable sleep.
[0066]
In the present invention, an autonomic nerve index is calculated as follows.
[0067]
Pulse fluctuation and pulse rate are obtained from the RR interval of the A / D-converted pulse wave signal, and the time series data of the calculated pulse rate is subjected to FFT (Fast Fourier Transform) to obtain power based on the pulse frequency component. Perform spectrum analysis. In this power spectrum data, the low frequency band component: LF is 0.2 Hz or less, and the high frequency band component: HF is higher than 0.2 Hz. Using this value, LF is used as it is for the activity of the parasympathetic nerve, and the value A calculated by HF / (HF + LF) is used for the activity of the sympathetic nerve.
[0068]
Therefore, the CPU 10 calculates the parasympathetic activity LF and the sympathetic activity A (step S41). It is determined whether or not the calculated LF is higher than the average value of the LF in the current sleep stage: LFs (step S42). And Further, it is determined whether or not the calculated A is higher than the average value As of A at the current stage (step S43). If it is higher, the pillow height is lowered because of an uncomfortable sleep state ( In step S44), when the pillow height is low, the pillow height is gradually raised in order to restore the lowered pillow height as a period in which the sleep state is gradually shifting from the uncomfortable sleep state to the comfortable state (step S45).
[0069]
The calculated current LF and A are also calculated as data of the average values LFs and As to update LFs and As (step S46), and are stored in the ROM in the microcomputer 10 (step S47).
[0070]
Although the embodiment of the present invention has been described above, the sleep state can be determined simply from information such as the change in the respiratory rate, the change in the pulse rate, and the frequency of the body movement. It is possible to use such a configuration.
[0071]
Also, here, the case in which the number of air bags in the pillow 1 is two has been described. However, if this number is increased, the number of places where the pillow height can be set increases, and it becomes possible to fit the shape of the user's head more.
[0072]
The means for setting the height of the pillow is not limited to a form using an air bag, and a bag filled with a liquid, or even without using a bag, can be combined with a gear and a rack to mechanically control the upper surface of the pillow. May be lifted.
[0073]
Further, the case where the air bag in the pillow 1 and the air mat for the sensor are separately provided has been described, but a structure in which the air bag and the air mat are shared may be adopted.
[0074]
Further, in the present embodiment, the pillow and the control box are connected by wire, but a wireless connection using radio waves or infrared rays can be used without any problem.
[0075]
Alternatively, it is not necessary to limit the control box to being provided separately from the pillow, and the present invention can be implemented even when the control box is built in the pillow.
[0076]
There are many known methods for obtaining the activity of the autonomic nerve from the pulse wave. In this case, the FFT is used as the time-frequency analysis means, but a wavelet transform may be used, or a method of simply filtering the RR interval of the pulse wave, a MEM (maximum entropy method), an AR method, or the like. Can also obtain the same autonomic nervous activity.
[0077]
Further, the skin potential may be used as the sympathetic nerve activity.
[0078]
【The invention's effect】
With the pillow-type sleep measurement device of the present invention, it is determined whether or not the current sleep environment is comfortable using the measured biological signal during sleep, and the height of the pillow is changed. And a comfortable sleeping environment can be provided. In addition, since the sensor is in the form of a pillow, the area in which the sensor contacts the floor is small, and the S / N ratio with respect to disturbance such as vibration of the building is relatively improved. This means that the measurement environment is good.
[0079]
Further, with the pillow-type sleep measurement device of the present invention, an index based on the autonomic nervous system is calculated using the measured biological signal during sleep, and it is determined whether the current sleep environment is comfortable. The current sleep environment can be accurately determined, and the height of the pillow can be more appropriately controlled.
[0080]
In addition, if the pillow-type sleep measurement device of the present invention, the sleep depth and the index based on the autonomic nerve is calculated using the measured biological signal during sleep, from the autonomic nerve index according to the sleep depth. Since it is determined whether the current sleep environment is comfortable, the current sleep environment can be more accurately determined, and the control of the height of the pillow becomes more appropriate.
[0081]
In addition, according to the pillow-type sleep measurement device of the present invention, the height of the pillow is appropriately changed in accordance with the occurrence of snoring of the subject, so that the subject can eliminate snoring and obtain a comfortable sleep. .
[Brief description of the drawings]
FIG. 1 is an external view of an apparatus according to an embodiment of the present invention.
FIG. 2 is an apparatus block diagram according to the embodiment of the present invention.
FIG. 3 is an internal sectional view of a pillow of the device according to the embodiment of the present invention.
FIG. 4 is a flowchart of an apparatus according to an embodiment of the present invention.
FIG. 5 is a flowchart of an apparatus according to an embodiment of the present invention.
FIG. 6 is a flowchart of an apparatus according to an embodiment of the present invention.
[Explanation of symbols]
1 Pillow 2 Operation box 3 Code 4 Switch unit 5 LCD
Reference Signs List 6 air-filled bag 7 air pressure adjusting device 8 sensor 9 key input device 10 microcomputer 11 input amplifier power supply device 12 low-pass filter 13 band-pass filter 14 high-pass filter 15 body movement amplifier 16 heartbeat amplifier 17 respiration amplifier 18 A / D converter 19 EEPROM
20 Buzzer

Claims (10)

Pillow height setting means for setting the height of the pillow,
Biological signal detecting means for detecting a biological signal,
A pillow type comprising: determining means for determining the comfort of the subject based on the detected biological signal; and control means for controlling the pillow height setting means based on the sleep comfort of the subject determined by the determining means. Sleep measurement device. Pillow height setting means for setting the height of the pillow,
Biological signal detecting means for detecting a biological signal,
Determining an index based on the autonomic nervous system from the detected biological signal, determining means for determining the comfort of the subject's sleep from the calculated index,
A pillow-type sleep measuring device comprising control means for controlling the pillow height setting means based on the sleep comfort of the subject determined by the determination means. Pillow height setting means for setting the height of the pillow,
Biological signal detecting means for detecting a biological signal,
From the detected biological signal, calculate an index based on the sleep depth and the autonomic nervous system, determining means for determining the comfort of the subject's sleep from the current sleep depth and the calculated index,
A pillow-type sleep measuring device comprising control means for controlling the pillow height setting means based on the sleep comfort of the subject determined by the determination means. The pillow-type sleep measurement device according to any one of claims 1 to 3, wherein the pillow height setting means is capable of setting a plurality of heights of the pillow. The pillow-type sleep measuring device according to any one of claims 1 to 3, wherein the biological signal detected by the biological signal detecting means is related to a heart rate. The pillow-type sleep measuring device according to any one of claims 1 to 3, wherein the biological signal detected by the biological signal detecting means is related to respiration. The pillow-type sleep measuring device according to any one of claims 1 to 3, wherein the biological signal detected by the biological signal detecting means is related to body movement. The determination means calculates the activity of the sympathetic nerve and the activity of the parasympathetic nerve from the pulse wave signal detected by the biological signal detection means,
The pillow-type sleep measuring device according to claim 2 or 3, wherein the index of the autonomic nerve uses the activity of the sympathetic nerve and the activity of the parasympathetic nerve. 9. The pillow-type sleep measuring apparatus according to claim 8, wherein the determination means calculates the activity of the sympathetic nerve and the activity of the parasympathetic nerve from the pulse wave signal by performing time-frequency analysis of the pulse. The pillow height setting means is provided so as to be able to set the height of at least two places in front and back of the pillow,
The biological signal detected by the detection means is related to snoring,
The determining means determines whether snoring has occurred,
The pillow-type sleep measurement device according to any one of claims 1 to 3, wherein the control unit lowers the front of the pillow and raises the back of the pillow when snoring occurs.

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