Physiological information measurement system, physiological information measurement method, and physiological information measurement program

Abstract

To provide a physiological information measurement system capable of determining whether a change in a measured pressure waveform is caused by deterioration or failure of a sensor or by a change in the condition of a measurement subject.SOLUTION: A physiological information measurement system includes: an obtaining unit configured to obtain, from a plurality of sensors that are connected to an air bag containing air and measure pressures received by the air bag from a subject, signals related to the measured pressures; and a determination unit configured to determine at least one of deterioration and failure of at least one of the sensors based on the signals related to the pressures obtained from the plurality of sensors.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a biological information measuring system, a biological information measuring method, and a biological information measuring program. [Background technology]

[0002] In medical facilities such as hospitals, it may be necessary to measure the biometric information of a patient lying on his / her back or side on a bed, such as heart rate and respiration, non-invasively without moving the patient. In addition, in nursing homes, it is necessary to prevent users from wandering around with a limited number of staff and ensure the safety of the users. To deal with such a situation, a prior art has been known in which an air bag is placed under a mattress on a bed, and the pressure that the air bag receives from a patient lying on his / her back or side is detected by a pressure sensor, a microphone, or the like, to measure the heart rate, respiration, and the like of the patient on the bed (for example, Patent Document 1 below). In this technology, the patient's admission / exit is determined by comparing the amplitude of the detected biometric information such as respiration or heart rate with a predetermined threshold value. In addition, in recent years, a product has been developed that analyzes the state of a patient on a bed, such as sleep / wake, admission / exit, lying / getting out of bed, and changes in respiration and heart rate, from the measured body movement waveform, and notifies medical personnel of changes in the patient's condition. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-159804 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the above-mentioned prior art cannot determine the deterioration or failure of the pressure sensor, and therefore cannot determine whether the change in the pressure waveform measured by the pressure sensor is due to the deterioration or failure of the pressure sensor or due to a change in the patient's condition. This causes a problem that the condition of the patient on the bed cannot be accurately grasped.

[0005] The present invention has been made to solve such problems, and aims to provide a biological information measuring system, a biological information measuring method, and a biological information measuring program that are capable of determining whether a change in the measured pressure waveform is due to deterioration or failure of the sensor or a change in the subject's condition. [Means for solving the problem]

[0006] The above-mentioned object of the present invention is achieved by the following means.

[0007] (1) A bioinformation measuring system having: an acquisition unit that acquires signals related to the measured pressure from a plurality of sensors that are connected to an air bag containing air and that each measure the pressure that the air bag receives from a subject; and a determination unit that determines at least one of deterioration and failure of at least one of the sensors based on the plurality of pressure-related signals acquired from the plurality of sensors.

[0008] (2) A method for measuring biological information comprising: an acquisition step of acquiring signals related to the measured pressure from a plurality of sensors connected to an air bag containing air, each of the sensors measuring the pressure the air bag receives from a subject; and a determination step of determining at least one of deterioration and failure of at least one of the sensors based on the plurality of pressure-related signals acquired from the plurality of sensors.

[0009] (3) A bioinformation measurement program for causing a computer to execute the following steps: an acquisition step of acquiring signals related to the measured pressure from a plurality of sensors connected to an air bag containing air, each of which measures the pressure received by the air bag from a subject; and a determination step of determining whether at least one of the sensors has deteriorated or failed based on the plurality of pressure-related signals acquired from the plurality of sensors. Effect of the Invention

[0010] The system acquires signals related to the measured pressure from a plurality of sensors connected to an air bag containing air, and judges at least one of the deterioration and failure of at least one of the sensors based on the acquired signals related to the pressure, thereby making it possible to determine whether a change in the measured pressure waveform is due to deterioration or failure of the sensor or a change in the condition of the person being measured. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a biological information measuring system. [Diagram 2] 1 is a block diagram illustrating a schematic configuration of a biological information measuring device. [Diagram 3] FIG. 2 is a block diagram illustrating a schematic configuration of an analysis unit. [Figure 4] 4 is a schematic diagram illustrating a display screen of an operation display unit. FIG. [Diagram 5] 4 is a flowchart showing the operation of the biological information measuring device. [Figure 6] 6 is a subroutine flowchart of step S103 in the flowchart of FIG. 5. [Figure 7] FIG. 4 is a diagram showing pressure waveforms output by each sensor. [Figure 8] FIG. [Figure 9] FIG. [Figure 10] 10A and 10B are schematic diagrams illustrating examples of data displayed on an operation display unit. [Figure 11] FIG. 11 is a block diagram illustrating a schematic configuration of a second modified example of a biological information measuring device. [Figure 12] FIG. 13 is a block diagram illustrating a schematic configuration of a third modified example of a biological information measuring device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, a biological information measurement system, a biological information measurement method, and a biological information measurement program according to an embodiment of the present invention will be described in detail with reference to the drawings. In the drawings, the same elements are given the same reference numerals, and duplicated descriptions will be omitted.

[0013] (Configuration of Biometric Information Measurement System) FIG. 1 is a diagram showing a schematic configuration of a biological information measurement system 10 according to an embodiment. FIG. 2 is a block diagram showing a schematic configuration of a biological information measurement device 300. In this embodiment, a situation is assumed in which a patient or user (hereinafter also referred to as "subject 120") lies on a bed 110 on which a mattress 100 is laid in a medical facility such as a hospital or a nursing home, and the respiration and / or heart rate of the subject 120 is measured. The biological information measurement system 10 is a system whose main purpose is to non-invasively measure the respiration rate and heart rate of the subject 120 lying on the bed 110 and continuously display and record the measured respiration rate and heart rate, and can be used, for example, in a general ward of a hospital or in a general home.

[0014] The biological information measurement system 10 includes a mat 210, a tube 220, and a biological information measurement device 300. The biological information measurement system 10 may further include a thermometer / hygrometer 230. The thermometer / hygrometer 230 constitutes a temperature / humidity measurement unit. The biological information measurement system 10 may be composed of only the biological information measurement device 300. The biological information measurement system 10 may be composed of the mat 210, the tube 220, the biological information measurement device 300, the thermometer / hygrometer 230, and a terminal device 400. The thermometer / hygrometer 230 may be built into the biological information measurement device 300 of the biological information measurement system 10.

[0015] The mat 210 includes a sealed air bag 211. The air bag 211 has an outlet for discharging the contained air, and one end of a tube 220 is connected to the outlet. The air in the air bag 211 is discharged to the biological information measuring device 300 through the tube 220. The other end of the tube 220 is connected to the biological information measuring device 300. The length of the tube 220 does not matter, and there is a case where the tube 220 does not protrude outside the biological information measuring device 300. The air bag 211 is airtight and is formed using a material (e.g., resin, rubber, etc.) that is elastically deformable by the pressure of the contained air. The air bag 211 has an elastic body with a compressible porous body (e.g., sponge) inside, and air is taken in from the outside by the restoring force of the elastic body, and the air is filled.

[0016] The mat 210, with the air bag 211 sufficiently filled with air, can be placed, for example, between the lower surface of the mattress 100 and the upper surface of the floorboard of the bed 110, at a position corresponding to the back (thorax and abdomen) of the subject 120 lying on the bed 110. When the subject 120 lies (gets in bed) on the bed 110, the mat 210 is subjected to the load of the subject 120 lying on the bed 110 and the mattress 100, and pressure due to the body movement of the subject 120, including the movement of the thorax accompanying breathing movement and minute vibrations accompanying the heartbeat. Therefore, the volume of the air bag 211 changes according to the pressure received from the subject 120, and the pressure change is transmitted to the biological information measurement device 300 through the tube 220. The biological information measurement device 300 can be installed in the bed 110.

[0017] The mat 210 may be placed at a position corresponding to the back (thorax and abdomen) of the subject 120 on the mattress 100 laid on the bed 110. In this case, the weight of the subject 120 lying on the bed 110 and the pressure due to the body movement of the subject 120 are applied to the mat 210.

[0018] The thermometer / hygrometer 230 measures the temperature (air temperature) and humidity, and transmits the measurement results to the biological information measuring device 300. The thermometer / hygrometer 230 is preferably installed in a position as close as possible to the mat 210. The measurement results of the thermometer / hygrometer 230 are used to check the environmental condition around the patient and to check the effect on the measurement performance of the first sensor 311 and the second sensor 312 described later.

[0019] [Configuration of Biological Information Measurement Device 300] 2, the biological information measuring device 300 includes a first sensor 311, a second sensor 312, a first signal processing unit 320A, a second signal processing unit 320B, an A / D conversion unit 330, an analysis unit 340, a power supply voltage measurement unit 360, and a system unit 350. The first signal processing unit 320A, the second signal processing unit 320B, and the A / D conversion unit 330 constitute an acquisition unit. The analysis unit 340 constitutes a determination unit and an abnormality occurrence time measurement unit.

[0020] [Configuration of the first sensor 311] First sensor 311 is connected to the other end of tube 220, converts the pressure change of the air from air bag 211 into an electric signal, and outputs it as a signal related to pressure (pressure waveform) to signal processor 320. First sensor 311 is, for example, a pressure sensor such as a sensor using a piezoelectric element or a semiconductor sensor. A pressure sensor capable of measuring negative pressure is used as first sensor 311, and it is configured to be able to measure body movement changes even when negative pressure is generated.

[0021] [Configuration of second sensor 312] Second sensor 312 is connected to the other end of tube 220, converts the change in air pressure from air bag 211 into an electric signal, and outputs it as a signal related to pressure (pressure waveform) to signal processing unit 320. Second sensor 312 may be the same type of sensor (e.g., the same product) as first sensor 311. Hereinafter, when the term "sensor" is used, it means either or both of the sensors without distinguishing between first sensor 311 and second sensor 312.

[0022] [Configuration of first signal processing unit 320A] The first signal processing unit 320A processes the measurement result of the first sensor 311 to obtain signals related to the dynamic pressure and static pressure of the subject 120. The dynamic pressure is a body movement component including the respiratory movement and cardiac movement of the subject 120. The static pressure is a pressure caused by a change in the load of the subject 120. The first signal processing unit 320A includes a first amplifier circuit 321A, a high-pass filter (HPF) 322A, a second amplifier circuit 323A, and a low-pass filter (LPF) 324A.

[0023] The first amplifier circuit 321A amplifies the electrical signal from the first sensor 311 to a predetermined voltage level and outputs it. The HPF 322 extracts AC components equal to or higher than a predetermined first cutoff frequency fc1 from the electrical signal amplified by the first amplifier circuit 321A and outputs it to the A / D conversion unit 330. The first cutoff frequency fc1 is a frequency that can pass frequency components corresponding to dynamic pressure while sufficiently blocking frequency components corresponding to static pressure. For example, fc1 can be set to a frequency that can pass frequency components derived from breathing. The frequency derived from breathing can be set based on information about the subject 120, for example, to about 0.1 to 0.4 [Hz] for an adult.

[0024] The second amplifier circuit 323A amplifies the electrical signal from the first sensor 311 to a predetermined voltage level and outputs it. The LPF 324A extracts AC (and DC) components below a predetermined second cutoff frequency fc2 from the electrical signal amplified by the second amplifier circuit 323A and outputs it to the A / D conversion unit 330. The second cutoff frequency fc2 is a frequency that can pass frequency components corresponding to static pressure while sufficiently blocking frequency components corresponding to dynamic pressure. The first and second cutoff frequencies may be the same value or different values ​​(fc1>fc2).

[0025] [Configuration of second signal processing unit 320B] Similar to the first signal processing unit 320A, the second signal processing unit 320B processes the measurement results of the second sensor 312 to obtain signals related to the dynamic pressure and static pressure of the subject 120. The second signal processing unit 320B includes a third amplifier circuit 321B, an HPF 322B, a fourth amplifier circuit 323B, and an LPF 324B.

[0026] The third amplifier circuit 321B amplifies the electrical signal from the second sensor 312 to a predetermined voltage level and outputs it. The HPF 322B extracts AC components equal to or higher than a predetermined third cutoff frequency fc3 from the electrical signal amplified by the third amplifier circuit 321B and outputs it to the A / D conversion unit 330. The third cutoff frequency fc3 is a frequency that can pass frequency components corresponding to dynamic pressure while sufficiently blocking frequency components corresponding to static pressure. In this embodiment, the third cutoff frequency fc3 can be the same value as the first cutoff frequency fc1.

[0027] The fourth amplifier circuit 323B amplifies the electrical signal from the second sensor 312 to a predetermined voltage level and outputs it. The LPF 324B extracts AC (and DC) components below a predetermined fourth cutoff frequency fc4 from the electrical signal amplified by the fourth amplifier circuit 323B and outputs it to the A / D conversion unit 330. The fourth cutoff frequency fc4 is a frequency that can pass frequency components corresponding to static pressure while sufficiently blocking frequency components corresponding to dynamic pressure. In this embodiment, the fourth cutoff frequency fc4 can be the same value as the second cutoff frequency fc2.

[0028] The first cutoff frequency fc1 and the third cutoff frequency fc3, and the second cutoff frequency fc2 and the fourth cutoff frequency fc4 may be the same value or may be different values.

[0029] [Configuration of A / D conversion unit 330] The A / D conversion unit 330 converts the electrical signal (analog signal) of the dynamic pressure input from the HPF 322A into a digital signal of the dynamic pressure and outputs it to the analysis unit 340 as a first dynamic pressure waveform. The A / D conversion unit 330 converts the electrical signal (analog signal) of the static pressure input from the LPF 324A into a digital signal of the static pressure and outputs it to the analysis unit 340 as a first static pressure waveform. The A / D conversion unit 330 converts the electrical signal (analog signal) of the dynamic pressure input from the HPF 322B into a digital signal of the dynamic pressure and outputs it to the analysis unit 340 as a second dynamic pressure waveform. The A / D conversion unit 330 converts the electrical signal (analog signal) of the static pressure input from the LPF 324B into a digital signal of the static pressure and outputs it to the analysis unit 340 as a second static pressure waveform.

[0030] The output signal of the first amplifier circuit 321A (or the second amplifier circuit 323A) and the output signal of the third amplifier circuit 321B (or the fourth amplifier circuit 323B) may be further input to the A / D conversion unit 330, converted into a pressure signal of a digital signal, and output to the analysis unit 340 as a pressure waveform before filtering by the HPF 322 or the LPF 324 (hereinafter also referred to as the "original pressure waveform"). As will be described later, the original pressure waveform may be used to determine whether the signal of any of the sensors is outside the design range in step S201 of FIG. 6.

[0031] [Configuration of analysis unit 340] 3 is a block diagram illustrating a schematic configuration of the analysis unit 340. The analysis unit 340 has a central processing unit (CPU) 341, a read only memory (ROM) 342, a random access memory (RAM) 343, and an input / output I / F 344. The CPU 341, the ROM 342, and the RAM 343 configure a computer.

[0032] The CPU 341 loads a biological information measurement program stored in advance in the ROM 342 into the RAM 343 and executes it to realize various functions.

[0033] The ROM 342 is a non-volatile memory. The ROM 342 stores an OS (Operating System), programs such as a biological information measurement program, and various parameters required for the calculation processing of the CPU 341. Note that the ROM 342 may be further configured to include, for example, an SSD (Solid State Drive) or an HDD (Hard Disk Drive) for storing the calculation results by the CPU 341 and various data.

[0034] The RAM 343 is a volatile memory and temporarily stores various data.

[0035] The input / output I / F 344 is an input / output interface for transmitting and receiving data to and from the system unit 350 .

[0036] The analysis unit 340 calculates the respiratory waveform, respiratory rate, heart rate waveform, and heart rate of the subject 120 based on the first dynamic pressure waveform output from the A / D conversion unit 330. More specifically, the analysis unit 340 generates a respiratory waveform based on a waveform obtained by extracting frequency components derived from breathing from the first dynamic pressure waveform, and calculates the respiratory rate of the subject 120 using a predetermined analysis algorithm for calculating the respiratory rate. For example, when the subject 120 is an adult, the frequency components derived from breathing can be extracted using a digital filter that passes waveform components of approximately 0.1 to 1.0 [Hz]. Furthermore, the analysis unit 340 generates a heart rate waveform based on a waveform obtained by extracting frequency components derived from the heart rate from the first dynamic pressure waveform, and calculates the heart rate of the subject 120 using a predetermined analysis algorithm for calculating the heart rate.

[0037] The analysis unit 340 judges the state of the subject 120 (e.g., lying position, posture (lying position), turning over, getting out of bed, etc.) based on the first dynamic pressure waveform and / or the first static pressure waveform. For example, the analysis unit 340 judges whether the subject 120 is in bed / out of bed based on the first static pressure waveform. When the first static pressure waveform is greater than a predetermined judgment threshold, the analysis unit 340 judges that the subject 120 is in bed, whereas when the first static pressure waveform is less than the judgment threshold, the analysis unit 340 judges that the subject 120 is out of bed. The judgment threshold can be stored in the ROM 342 in advance. Moreover, the analysis unit 340 can detect the state of the subject 120 more accurately by analyzing the first dynamic pressure waveform and the first static pressure waveform in combination. For example, the analysis unit 340 may be configured to determine that the subject 120 is in bed if the first static pressure waveform is greater than a predetermined judgment threshold and, in addition, the breathing and / or heart rate of the subject 120 can be confirmed based on the first dynamic pressure waveform.

[0038] The analysis unit 340 may be configured to calculate a determination threshold used to determine the state of the subject 120, based on the first dynamic pressure waveform and / or the first static pressure waveform of the subject 120. For example, the analysis unit 340 may be configured to calculate a determination threshold for determining whether the subject 120 is in bed / out of bed, based on the first dynamic pressure waveform and the first static pressure waveform of the subject 120.

[0039] The analysis unit 340 calculates each judgment threshold based on the first dynamic pressure waveform and the first static pressure waveform of the subject 120 acquired at the start of pressure measurement by the first sensor 311 or at every predetermined time. For example, the analysis unit 340 calculates a judgment threshold for judging whether the subject 120 is in bed or out of bed based on the first dynamic pressure waveform and the first static pressure waveform of the subject 120 at the timing when the subject 120 enters bed and the measurement of breathing is started. This allows an appropriate judgment threshold according to the weight of the subject 120 to be applied to the state judgment. Alternatively, the analysis unit 340 calculates a judgment threshold for judging whether the subject 120 is in bed or out of bed based on the first dynamic pressure waveform and the first static pressure waveform acquired for a certain period from the timing of every predetermined time. This allows a judgment threshold according to the different subject 120 to be applied even when the user of the bed 110 is changed from the subject 120 to another subject.

[0040] The analysis unit 340 estimates the weight of the subject 120 based on the change in the first static pressure waveform. The analysis unit 340 estimates the weight of the subject 120 based on a lookup table or a relational expression that indicates the relationship between the magnitude of the value of the first static pressure waveform and the weight of the subject 120. For example, a user who is a medical professional measures the weight of each of the multiple subjects 120 and the magnitude of the value of the static pressure waveform corresponding to that weight in advance, and stores them in the ROM 342 as a lookup table or a relational expression.

[0041] The analysis unit 340 judges whether or not a weight equal to or greater than the load capacity is applied to the mat 210 based on the first static pressure waveform.

[0042] The analysis unit 340 determines whether or not the estimated value of the weight of the subject 120 or the tendency of the respiration waveform / heart rate waveform has changed suddenly. For example, if the estimated value of the weight of the subject 120 has changed suddenly, it is possible that the subject 120 has left bed or has been replaced by another person with a different weight. Also, if the tendency of the respiration waveform / heart rate waveform has changed suddenly, it is possible that the condition of the subject 120 has changed or the subject has been replaced by another person with a different tendency of the respiration / heart rate waveform.

[0043] As described above, the biological information of the subject 120 is measured based on the first dynamic pressure waveform and the first static pressure waveform. The second dynamic pressure waveform and the second static pressure waveform are used to determine at least one of deterioration and failure of at least one of the first sensor 311 and the second sensor 312, as described below, and may be used to measure the biological information of the subject.

[0044] The analysis unit 340 determines at least one of the deterioration and failure of at least one sensor based on a plurality of pressure-related signals. Specifically, the analysis unit 340 determines at least one of the deterioration and failure of the first sensor 311 and the second sensor 312 based on, for example, the first dynamic pressure waveform and the second dynamic pressure waveform. The analysis unit 340 may determine at least one of the deterioration and failure of the first sensor 311 and the second sensor 312 based on the first static pressure waveform and the second static pressure waveform. The analysis unit 340 may determine at least one of the deterioration and failure of the first sensor 311 and the second sensor 312 based on the first dynamic pressure waveform, the second dynamic pressure waveform, the first static pressure waveform, and the second static pressure waveform. The analysis unit 340 may determine at least one of the deterioration and failure of at least one sensor of the three or more sensors based on three or more pressure-related signals of the three or more sensors. Furthermore, the three or more pressure-related signals of the three or more sensors may be used to measure biological information of the subject. For ease of explanation, the following description will be given taking as an example a case where the analysis unit 340 judges at least one of the first sensor 311 and the second sensor 312 to be degraded or broken based on a plurality of pressure-related signals from the two sensors. Hereinafter, the judgment of at least one of the sensor degradation and failure will be simply referred to as "determination of degradation, etc." The judgment that at least one sensor is broken will be simply referred to as "determination of failure." The judgment that at least one sensor is degraded will be simply referred to as "determination of degradation." A specific method of the judgment of degradation, etc. will be described in detail later.

[0045] [Configuration of system unit 350] Fig. 4 is a schematic diagram illustrating a display screen of operation display unit 352 shown in Fig. 2. System unit 350 includes transmission unit 351, operation display unit 352, and recording unit 353. Transmission unit 351 and operation display unit 352 configure a notification unit.

[0046] The transmitting unit 351 transmits to the terminal device 400 the results of the analysis of respiration / heartbeat by the analyzing unit 340 (respiratory rate / heart rate, respiratory waveform / heartbeat waveform, trend graph, etc.), the state of the subject 120, alarms, and data related to the determination of deterioration, etc. The state of the subject 120 includes, for example, whether the subject 120 is in bed / out of bed, body position (supine position), a trend graph of changes in body position, position, estimated weight value, health condition, etc. The alarms include alarms of body movement, sensor deterioration, and sensor failure. The data related to the determination of deterioration, etc. includes, for example, a signal related to pressure, a first dynamic pressure waveform, a first static pressure waveform, a second dynamic pressure waveform, a second static pressure waveform, temperature (air temperature) and humidity measured by the thermo-hygrometer 230, and data on the power supply voltage measured by the power supply voltage measuring unit 360.

[0047] At least one of the sensor degradation and the sensor failure is notified by transmitting an alarm of the occurrence of sensor degradation and the occurrence of sensor failure by the transmitting unit 351. As described later, degradation of the static pressure function and the dynamic pressure function of the sensor and the failure of the static pressure function and the dynamic pressure function of the sensor can be determined. In this case, the transmitting unit 351 transmits an alarm of the occurrence of degradation of the static pressure function and the dynamic pressure function of the sensor and the failure of the static pressure function and the dynamic pressure function of the sensor. In this way, the degradation and the failure of the static pressure function and the dynamic pressure function of the sensor are notified.

[0048] The user can check the data transmitted from the transmission unit 351 on the terminal device 400 and store it in a storage device. The terminal device 400 can be, for example, a personal computer, a smartphone, a tablet terminal, or the like.

[0049] The transmission unit 351 and the terminal device 400 are connected to each other via a wireless / wired network so that they can communicate with each other. The network is, for example, a local area network (LAN), a wide area network (WAN), a USB, etc. For example, Ethernet (registered trademark), Wi-Fi (registered trademark), Bluetooth (registered trademark), a specific low-power radio for medical telemetry, or 5G may be used as the communication standard of the network.

[0050] The operation display unit 352 has, for example, a touch panel, various keys, switches, etc., and accepts user instructions, various settings, information about the patient (subject 120), etc. The user instructions include, for example, an instruction to determine deterioration, etc. The various settings include, for example, settings about the data output method and display method, etc. The information about the patient includes the patient's gender, age, medical history, etc.

[0051] The operation display unit 352 has a display arranged on one side of the housing of the biological information measuring device 300, and a speaker (not shown), and outputs the results of the respiration / heartbeat analysis by the analysis unit 340, data related to the state of the subject 120, alarms, and deterioration and other judgments. The output of the operation display unit 352 includes, for example, displaying the above data on a display, outputting audio to a speaker, and printing out to a printer. The operation display unit 352 can be connected to an external printer. FIG. 4 illustrates an example in which a trend graph TG1 of the respiration rate and a trend graph TG2 of the heart rate are displayed on the display. Details of data display on the display will be described later.

[0052] The recording unit 353 has a large-capacity storage device such as an SSD, and records various data including the above data.

[0053] Power supply voltage measuring unit 360 measures and outputs the power supply voltages of first sensor 311 and second sensor 312. A known voltmeter (including a voltage measurement circuit) may be used as power supply voltage measuring unit 360. Power supply voltage measuring unit 360 may measure and output the power supply voltages of first signal processing unit 320A and second signal processing unit 320B.

[0054] (Biometric information measurement method) Fig. 5 is a flowchart showing the operation of the biological information measuring device 300 of this embodiment. Fig. 6 is a subroutine flowchart of step S103 in the flowchart of Fig. 5. These flowcharts are realized by CPU 341 executing the biological information measuring program. Fig. 7 is a diagram showing pressure waveforms output by each sensor. Fig. 8 is a diagram showing a static pressure waveform. Fig. 9 is a diagram showing a dynamic pressure waveform. Fig. 10 is a schematic diagram showing an example of data display on operation display unit 352.

[0055] [Measurement preparation] First, prior to measuring the biological information of the subject 120, the user places the mat 210 between the underside of the mattress 100 and the upper surface of the floorboard of the bed 110, or on the mattress 100 at a position corresponding to the back (thorax and abdomen) of the subject 120. Then, after the subject 120 gets into bed 110, the user instructs the biological information measuring device 300 to start measurement (for example, by pressing a measurement start button). Alternatively, the measurement starts when the power of the biological information measuring device 300 is turned on.

[0056] [Measurement of biological information] As shown in FIG. 5, when measurement is started, first sensor 311 and second sensor 312 each measure the pressure from air bag 211, which is generated due to the body movement of subject 120, as a pressure waveform (S101).

[0057] Next, first signal processing section 320A, second signal processing section 320B, and A / D conversion section 330 acquire digital signals of dynamic pressure waveforms and static pressure waveforms as signals related to the dynamic pressure and static pressure of subject 120 (S102). Specifically, first signal processing section 320A, second signal processing section 320B, and A / D conversion section 330 acquire a first dynamic pressure waveform, a first static pressure waveform, a second dynamic pressure waveform, and a second static pressure waveform.

[0058] Next, the analysis unit 340 executes a determination regarding deterioration of the sensor, etc. (S103).

[0059] [Details of the process for determining sensor deterioration, etc. (S103)] As shown in FIG. 6, the analysis unit 340 judges whether at least any of the sensor signals has a value outside the design range (S201). The design range constitutes a predetermined threshold range. The value outside the design range is, for example, a value that exceeds the lower limit or upper limit that the pressure waveform value can take in design. Whether the sensor signal has a value outside the design range can be judged, for example, by whether the value of the pressure waveform output from the sensor exceeds the above-mentioned lower limit or upper limit of the design range (i.e., the predetermined threshold range). Specifically, the analysis unit 340 judges whether a pressure waveform has not been acquired from the first sensor 311 or the second sensor 312, and whether a pressure waveform with an abnormal value outside the design range has been acquired. More specifically, the analysis unit 340 judges, for example, whether any of the first dynamic pressure waveform, the first static pressure waveform, the second dynamic pressure waveform, and the second static pressure waveform has not been acquired, and whether any of the first dynamic pressure waveform, the first static pressure waveform, the second dynamic pressure waveform, and the second static pressure waveform has an abnormal value outside the design range. When the output signal of the first amplifier circuit 321A (or the second amplifier circuit 323A) and the output signal of the third amplifier circuit 321B (or the fourth amplifier circuit 323B) are input to the A / D conversion unit 330 and converted into original pressure signals which are digital signals and output to the analysis unit 340, it may be determined whether either of the two original pressure signals has been acquired and whether a pressure waveform with an abnormal value outside the design range has been acquired. The above-mentioned predetermined threshold range may be a value obtained by adjusting the above-mentioned design range.

[0060] When the analysis unit 340 determines that the signal of at least any one of the sensors is out of the design range (S201: YES), it determines that a failure has occurred (S214).

[0061] When the analysis unit 340 determines that none of the sensor signals are outside the design range (pressure waveforms within the design range have been acquired from all sensors) (S201: NO), it calculates the difference in the values ​​of the static pressure waveforms of each sensor (hereinafter also referred to as the "static pressure value difference") (S202).

[0062] The analysis unit 340 judges whether the difference between the static pressure values ​​of the sensors is equal to or greater than the degradation reference value of the static pressure measurement function (S203). The degradation reference value of the static pressure measurement function constitutes a first threshold. Specifically, the analysis unit 340 judges whether the difference between the values ​​of the first static pressure waveform and the second static pressure waveform is equal to or greater than the degradation reference value of the static pressure measurement function. More specifically, the analysis unit 340 judges whether the absolute value of the difference between the values ​​of the first static pressure waveform and the second static pressure waveform at the same time (difference in static pressure values), for example, is equal to or greater than the degradation reference value of the static pressure measurement function. The difference in static pressure values ​​includes not only the absolute value of the difference at the same time, but also, for example, the absolute value of the difference in average values ​​in the same time period. That is, in step S203, the analysis unit 340 may judge whether the absolute value of the difference between the average value of the first static pressure waveform and the average value of the second static pressure waveform in the same time period is equal to or greater than the degradation reference value of the static pressure measurement function. When three or more sensors are used, the analysis unit 340 may determine whether the difference between the static pressure waveforms (difference in static pressure values) based on the pressure waveforms measured by the sensors is equal to or greater than the degradation reference value of the static pressure measurement function. The degradation reference value of the static pressure measurement function may be set to an appropriate value through experiments from the viewpoint of the accuracy of the degradation judgment. The degradation reference value of the static pressure measurement function may be set by further considering the type, specifications, manufacturing variation, etc. of the sensor.

[0063] When the analysis unit 340 determines that the difference between the static pressure values ​​of the sensors is equal to or greater than the degradation reference value of the static pressure measurement function (S203: YES), it determines whether the difference between the static pressure values ​​of the sensors is equal to or greater than the failure reference value of the static pressure measurement function (S204). The failure reference value of the static pressure measurement function constitutes a second threshold. Specifically, the analysis unit 340 determines whether the difference between the first static pressure waveform and the second static pressure waveform (difference in static pressure values) is equal to or greater than the failure reference value of the static pressure measurement function. More specifically, the analysis unit 340 determines whether the absolute value of the difference between the first static pressure waveform and the second static pressure waveform at the same time (difference in static pressure values), for example, is equal to or greater than the failure reference value of the static pressure measurement function. Note that, when three or more sensors are used, the analysis unit 340 may determine whether the difference between the static pressure waveforms (difference in static pressure values) based on the pressure waveforms measured by the multiple sensors is equal to or greater than the failure reference value of the static pressure measurement function. The failure criterion value of the static pressure measurement function can be set to an appropriate value through experiments from the viewpoint of accuracy of determining deterioration, etc. The failure criterion value of the static pressure measurement function can be set by further considering the type, specifications, manufacturing variation, etc. of the sensor.

[0064] When the analysis unit 340 determines that the difference between the static pressure values ​​of the sensors is equal to or greater than the malfunction reference value of the static pressure measurement function (S204: YES), it determines that the static pressure measurement function is malfunctioning (S206). In this case, the analysis unit 340 may simply determine that the sensor is malfunctioning.

[0065] When the analysis unit 340 determines that the difference between the static pressure values ​​of the sensors is less than the malfunction reference value of the static pressure measurement function (S204: NO), it determines that the static pressure measurement function has deteriorated (S207). In this case, the analysis unit 340 may simply determine that the sensor has deteriorated.

[0066] When the control unit 340 determines in step S203 that the difference between the static pressure values ​​of the sensors is less than the degradation reference value of the static pressure measurement function (S203: NO), it determines that the static pressure measurement function is normal (S205).

[0067] Through steps S202 to S207, the analysis unit 340 determines that the static pressure measurement function of the sensor has deteriorated if the difference between the first static pressure waveform and the second static pressure waveform is equal to or greater than the deterioration reference value (first threshold value) of the static pressure measurement function and less than the failure reference value (second threshold value) of the static pressure measurement function. Also, the analysis unit 340 determines that the static pressure measurement function of the sensor has failed if the difference between the first static pressure waveform and the second static pressure waveform is equal to or greater than the failure reference value (second threshold value) of the static pressure measurement function. Note that the failure reference value of the static pressure measurement function is naturally greater than the deterioration reference value of the static pressure measurement function.

[0068] The analysis unit 340 may determine that the difference between the first static pressure waveform and the second static pressure waveform is equal to or greater than the degradation reference value (first threshold value) of the static pressure measurement function and less than the failure reference value (second threshold value) of the static pressure measurement function when the state in which the difference between the first static pressure waveform and the second static pressure waveform is equal to or greater than the degradation reference value (first threshold value) of the static pressure measurement function and less than the failure reference value (second threshold value) of the static pressure measurement function continues for a predetermined first time. The predetermined first time may be set to an appropriate value through experiments from the viewpoint of accuracy of the determination of degradation, etc. The predetermined first time may be set by further considering the type and specifications of the sensor. The predetermined first time may be set to, for example, about 30 minutes (for example, a time in the range of 20 to 40 minutes).

[0069] The analysis unit 340 may determine that the difference between the first static pressure waveform and the second static pressure waveform exceeds the failure reference value (second threshold value) of the static pressure measurement function when the state in which the difference between the first static pressure waveform and the second static pressure waveform exceeds the failure reference value (second threshold value) of the static pressure measurement function continues for a predetermined second time. The predetermined second time may be set to an appropriate value through experiments from the viewpoint of accuracy of the determination of deterioration, etc. The predetermined second time may be set by further considering the type and specifications of the sensor. The predetermined first time may be set to, for example, about 30 minutes (for example, a time in the range of 20 to 40 minutes).

[0070] Steps S202 to S207 and steps S208 to S213 may be executed in parallel.

[0071] The analysis unit 340 calculates the difference between the values ​​of the dynamic pressure waveforms of the sensors (hereinafter also referred to as "difference in dynamic pressure values") (S208).

[0072] The analysis unit 340 judges whether the difference between the dynamic pressure values ​​of the sensors is equal to or greater than the degradation reference value of the dynamic pressure measurement function (S209). The degradation reference value of the dynamic pressure measurement function constitutes a third threshold. Specifically, the analysis unit 340 judges whether the difference between the values ​​of the first dynamic pressure waveform and the second dynamic pressure waveform is equal to or greater than the degradation reference value of the dynamic pressure measurement function. More specifically, the analysis unit 340 judges whether the absolute value of the difference between the values ​​of the first dynamic pressure waveform and the second dynamic pressure waveform at the same time (difference in dynamic pressure values), for example, is equal to or greater than the degradation reference value of the dynamic pressure measurement function. The difference in dynamic pressure values ​​includes not only the absolute value of the difference at the same time, but also, for example, the absolute value of the difference in average values ​​in the same time period. That is, in step S209, the analysis unit 340 may judge whether the absolute value of the difference between the average value of the first dynamic pressure waveform and the average value of the second dynamic pressure waveform in the same time period is equal to or greater than the degradation reference value of the dynamic pressure measurement function. When three or more sensors are used, the analysis unit 340 may determine whether the difference between multiple dynamic pressure waveforms (difference in dynamic pressure values) based on multiple pressure waveforms measured by the multiple sensors is equal to or greater than the degradation reference value of the dynamic pressure measurement function. The degradation reference value of the dynamic pressure measurement function may be set to an appropriate value through experiments from the viewpoint of accuracy of the determination of degradation, etc. The degradation reference value of the dynamic pressure measurement function may be set by further considering the type, specifications, manufacturing variation, etc. of the sensor.

[0073] When the analysis unit 340 determines that the difference between the dynamic pressure values ​​of the sensors is equal to or greater than the degradation reference value of the dynamic pressure measurement function (S209: YES), it determines whether the difference between the dynamic pressure values ​​of the sensors is equal to or greater than the failure reference value of the dynamic pressure measurement function (S210). The failure reference value of the dynamic pressure measurement function constitutes a fourth threshold. Specifically, the analysis unit 340 determines whether the difference between the first dynamic pressure waveform and the second dynamic pressure waveform (difference in dynamic pressure values) is equal to or greater than the failure reference value of the dynamic pressure measurement function. More specifically, the analysis unit 340 determines whether the absolute value of the difference between the first dynamic pressure waveform and the second dynamic pressure waveform at the same time (difference in dynamic pressure values), for example, is equal to or greater than the failure reference value of the dynamic pressure measurement function. Note that, when three or more sensors are used, the analysis unit 340 may determine whether the difference between the dynamic pressure waveforms (difference in dynamic pressure values) based on the pressure waveforms measured by the multiple sensors is equal to or greater than the failure reference value of the dynamic pressure measurement function. The failure criterion value of the dynamic pressure measurement function can be set to an appropriate value through experiments from the viewpoint of accuracy of determining deterioration, etc. The failure criterion value of the dynamic pressure measurement function can be set by further considering the type, specifications, manufacturing variation, etc. of the sensor.

[0074] When the analysis unit 340 determines that the difference between the dynamic pressure values ​​of the sensors is equal to or greater than the malfunction reference value of the dynamic pressure measurement function (S210: YES), it determines that the dynamic pressure measurement function is malfunctioning (S212). In this case, the analysis unit 340 may simply determine that the sensor is malfunctioning.

[0075] When the analysis unit 340 determines that the difference between the dynamic pressure values ​​of the sensors is less than the malfunction reference value of the dynamic pressure measurement function (S210: NO), it determines that the dynamic pressure measurement function has deteriorated (S213). In this case, the analysis unit 340 may simply determine that the sensor has deteriorated.

[0076] When the control unit 340 determines in step S209 that the difference between the dynamic pressure values ​​of the sensors is less than the degradation reference value of the dynamic pressure measurement function (S209: NO), it determines that the dynamic pressure measurement function is normal (S211).

[0077] Through steps S208 to S213, the analysis unit 340 determines that the dynamic pressure measurement function of the sensor has deteriorated if the difference between the first dynamic pressure waveform and the second dynamic pressure waveform is equal to or greater than the deterioration reference value (third threshold value) of the dynamic pressure measurement function and less than the failure reference value (fourth threshold value) of the dynamic pressure measurement function. Also, the analysis unit 340 determines that the dynamic pressure measurement function of the sensor has failed if the difference between the first dynamic pressure waveform and the second dynamic pressure waveform is equal to or greater than the failure reference value (fourth threshold value) of the dynamic pressure measurement function. Note that the failure reference value of the dynamic pressure measurement function is naturally greater than the deterioration reference value of the dynamic pressure measurement function.

[0078] The analysis unit 340 may determine that the difference between the first dynamic pressure waveform and the second dynamic pressure waveform is equal to or greater than the third threshold and less than the fourth threshold when a state in which the difference between the first dynamic pressure waveform and the second dynamic pressure waveform is equal to or greater than the degradation reference value (third threshold) of the dynamic pressure measurement function and less than the failure reference value (fourth threshold) of the dynamic pressure measurement function continues for a predetermined third time. The predetermined third time may be set to an appropriate value through experiments from the viewpoint of accuracy of the degradation judgment, etc. The predetermined third time may be set by further considering the type and specifications of the sensor. The predetermined third time may be set to, for example, about 30 minutes (for example, a time in the range of 20 to 40 minutes). The analysis unit 340 may determine that the difference between the first dynamic pressure waveform and the second dynamic pressure waveform exceeds the fourth threshold value when the state in which the difference between the first dynamic pressure waveform and the second dynamic pressure waveform exceeds the fourth threshold value continues for a predetermined fourth time. The predetermined fourth time may be set to an appropriate value through experiments from the viewpoint of accuracy of the determination of deterioration, etc. The predetermined fourth time may be set by further considering the type and specifications of the sensor. The predetermined fourth time may be set to, for example, about 30 minutes (for example, a time in the range of 20 to 40 minutes).

[0079] The analysis unit 340 measures the time from the point in time when the deterioration or other failure is determined as a result of the deterioration or other failure determination as the abnormality occurrence time, and records this in the recording unit 353 .

[0080] After the power supply of the biological information measuring device 300 is turned on, the analysis unit 340 may perform the deterioration etc. determination continuously, intermittently, or when a determination instruction is received. When the deterioration etc. determination is performed intermittently, the deterioration etc. determination may be performed at any time interval ranging from one minute to several hours, for example. The analysis unit 340 may receive the determination instruction by, for example, selecting a button displayed on the display of the operation display unit 352. The analysis unit 340 may receive the determination instruction by receiving the determination instruction transmitted from the terminal device 400 to the biological information measuring device 300 by selecting a button displayed on the display of the terminal device 400.

[0081] The analysis unit 340 determines whether or not there is a power supply failure based on the power supply voltage measured by the power supply voltage measurement unit 360, and when it is determined that there is no power supply failure, it may perform a determination of deterioration, etc. In other words, when it is determined that there is a power supply failure, the analysis unit 340 may not need to perform a determination of deterioration, etc. When the power supply voltage is not within a predetermined threshold range, the analysis unit 340 may determine that there is a power supply failure.

[0082] The analysis unit 340 can perform deterioration, etc., determination based on the temperature and humidity measured by the thermo-hygrometer 230. Specifically, for example, the analysis unit 340 corrects the first dynamic pressure waveform, the first static pressure waveform, the second dynamic pressure waveform, and the second static pressure waveform based on the temperature and humidity, and performs deterioration, etc., determination based on the corrected first dynamic pressure waveform, the first static pressure waveform, the second dynamic pressure waveform, and the second static pressure waveform.

[0083] [Data Display] Returning to the flowchart shown in FIG. 5, the operation display unit 352 outputs data (step S104). For example, the operation display unit 352 outputs to the display 360 the results of the analysis of the respiration / heart rate by the analysis unit 340 (respiration rate / heart rate, waveform, trend graph, etc.), the state of the subject 120, alarms, and data related to the determination of deterioration, etc. In this embodiment, when deterioration of the sensor occurs, an alarm of sensor deterioration is output for the subject 120 in whose bed 110 the sensor is placed. When a failure of the sensor occurs, an alarm of sensor failure is output for the subject 120 in whose bed 110 the sensor is placed. A situation is assumed in which the respiration and / or heart rate of the subject 120 is measured while the subject 120 is lying down. The biological information measurement system 10 is a system whose main purpose is to non-invasively measure the respiration rate and heart rate of the subject 120 lying down on the bed 110 and continuously display and record the measured respiration rate and heart rate, and can be used, for example, in a general ward of a hospital.

[0084] As shown in FIG. 10, the operation display unit 352 displays, for example, the respiratory rate, heart rate, in / out of bed, body position (supine position), and alarms of the patient (subject 120) together with the patient's room number on the display of the terminal device 400 or the upper part UP of the screen SC of the display. In the example shown in FIG. 10, an alarm of body movement occurrence is displayed for Koden Ichiro in room 103 and Koden Saburo in room 106, and an alarm of sensor deterioration occurrence is displayed for Koden Shiro in room 107. For example, the operation display unit 352 may display the words "body movement occurrence" together with a warning mark as an alarm of body movement occurrence when, for example, the subject 120 is moving vigorously and the waveform is disturbed. For example, the operation display unit 352 may display the words "sensor deterioration occurrence" together with a warning mark as an alarm of sensor deterioration occurrence.

[0085] In this embodiment, the analysis unit 340 is configured to determine whether the subject 120 is in bed or out of bed based on changes in the static pressure signal and / or dynamic pressure signal, and the operation display unit 352 is configured to accurately display the respiration rate / heart rate only when the subject 120 is in bed. This prevents an incorrect respiration rate / heart rate from being calculated and displayed when the bed user gets out of bed.

[0086] When the analysis unit 340 determines that a weight exceeding the load capacity is applied to the mat 210, the operation display unit 352 notifies the user of that effect. This makes it possible to prevent respiration / heart rate measurement from continuing in a state in which a weight exceeding the load capacity is applied to the mat 210 and accuracy cannot be guaranteed.

[0087] When it is determined that there has been a sudden change in the estimated value of the weight of the subject 120 or the tendency of the respiratory waveform / heart rate waveform, the operation display unit 352 notifies the user of that fact. When there has been a sudden change in the estimated value of the weight of the subject 120 or the tendency of the respiratory waveform / heart rate waveform, for example, there is a possibility that the condition of the subject 120 has changed or that the subject 120 has been replaced by another person, so the operation display unit 352 may be configured to notify the user of a possibility that the condition of the subject 120 has changed or that the user of the bed 110 has been replaced.

[0088] The operation display unit 352 displays, for example, in the lower part BT of the screen SC, detailed information about Taro Koden in room 101, such as information about in bed / out of bed, Taro Koden's position on the bed, estimated weight (specific values ​​are omitted in the figure), graphs related to respiration and heart rate, information about health condition, information about lying position, etc., in addition to the information in the upper part UP. From the data displayed on the screen SC, the user can immediately understand that Taro Koden is in bed, resting, lying in supine position in the center of the bed, his respiratory rate is 15, his heart rate is 60, his health condition is 10, he has left bed twice, and his time of leaving bed is 8 hours. Note that the number of times in bed / time of staying in bed may be displayed instead of the number of times of leaving bed / time of staying in bed. The information about health condition is, for example, an index (score) that evaluates the health condition of the subject 120 on a scale of 1 to 10, and is calculated based on changes in the respiratory rate / heart rate, and the respiratory waveform / heart rate waveform.

[0089] The graphs relating to respiration and heart rate may be, for example, real-time waveforms of respiration and heart rate, or trend graphs of respiration rate and heart rate. In the example shown in Fig. 10, for example, the history of being in bed, getting out of bed, and body movement in one day is displayed in the form of a bar graph as information relating to being in bed / getting out of bed, and the history of body position (lying position) (supine position or lateral position) in one day is displayed in the form of a bar graph as information relating to body position (lying position).

[0090] (First Modification) The first sensor 311 and the second sensor 312 may be different types of sensors. For example, one of the first sensor 311 and the second sensor 312 is a sensor using a piezoelectric element, and the other is a semiconductor sensor.

[0091] In this modified example, in order to calculate the difference in the waveforms, an adjustment is performed in advance to match the maximum value of the output of the first sensor 311 and the maximum value of the output of the second sensor 312.

[0092] Sensors of the same type generally have similar degradation rates. On the other hand, sensors of different types may have relatively different degradation rates. Therefore, by determining sensor degradation based on the difference between multiple waveforms acquired from sensors of different types, it is possible to prevent a decrease in the accuracy of determining sensor degradation caused by sensors of the same type having similar degradation rates, and to improve the accuracy of determining sensor degradation.

[0093] (Second Modification) FIG. 11 is a block diagram illustrating a schematic configuration of a second modified example of the biological information measuring device 300 shown in FIG.

[0094] In this modification, the biological information measuring device 300 is composed of two parts: a first body unit 370 including a first sensor 311, a second sensor 312, a first signal processing unit 320A, a second signal processing unit 320B, an A / D conversion unit 330, and a transmission unit 335, and a second body unit 380 including a transmission / reception / analysis unit 345 and a system unit 350. The first body unit 370 and the second body unit 380 may be arranged, for example, in different places in a hospital and configured to be able to communicate with each other. For example, the first body unit 370 may be arranged on a bed 110 in a patient's hospital room, and the second body unit 380 may be carried by a user. The second body unit 380 may also be a computer such as a server.

[0095] The configurations of the first sensor 311, the second sensor 312, the first signal processing unit 320A, the second signal processing unit 320B, and the A / D conversion unit 330 are the same as the corresponding configurations in the above-mentioned embodiments, so detailed description will be omitted. The transmission unit 335 transmits the first dynamic pressure waveform, the first static pressure waveform, the second dynamic pressure waveform, and the second static pressure waveform converted by the A / D conversion unit 330, as well as the power supply voltage output from the power supply voltage measurement unit 360, and the temperature and humidity received from the thermo-hygrometer 230 to the second main body unit 380. The transmission / reception analysis unit 345 of the second main body unit 380 receives the first dynamic pressure waveform, the first static pressure waveform, the second dynamic pressure waveform, the second static pressure waveform, the power supply voltage, and the temperature and humidity from the transmission unit 335.

[0096] The transmission / reception analysis unit 345 executes the functions executed by the analysis unit 340 in the above-described embodiment.

[0097] (Third Modification) FIG. 12 is a block diagram illustrating a schematic configuration of a third modified example of the biological information measuring device 300 shown in FIG.

[0098] In this modification, the second amplifier circuit and the fourth amplifier circuit are omitted. The LPF 324A extracts AC (and DC) components having a predetermined second cutoff frequency fc2 or less from the electrical signal amplified by the first amplifier circuit 321A, and outputs the AC (and DC) components having a predetermined fourth cutoff frequency fc4 or less from the electrical signal amplified by the third amplifier circuit 321B, and outputs the AC (and DC) components having a predetermined fourth cutoff frequency fc4 or less to the A / D converter 330.

[0099] Note that the biological information measuring device 300 of this modified example may be configured to include a first main body section 370 and a second main body section 380, similar to the second modified example.

[0100] The biological information measuring device 300 provides the following advantages.

[0101] The system acquires signals related to the measured pressure from a plurality of sensors connected to an air bag containing air, and judges at least one of the deterioration and failure of at least one of the sensors based on the acquired signals related to the pressure, thereby making it possible to determine whether a change in the measured pressure waveform is due to deterioration or failure of the sensor or a change in the condition of the person being measured.

[0102] In addition, the pressure-related signal is a pressure waveform, and at least one of deterioration and failure of the sensor is determined based on the difference between the multiple pressure waveforms. This makes it possible to determine deterioration and failure of the sensor simply and with high accuracy.

[0103] In addition, the multiple sensors are two different types of sensors, which can prevent a decrease in accuracy of sensor degradation determination caused by the multiple sensors having similar degradation rates due to the use of the same type of sensors.

[0104] Furthermore, if pressure waveforms within a predetermined threshold range are acquired from all of the multiple sensors, and the difference between multiple static pressure waveforms based on the acquired pressure waveforms is equal to or greater than a first threshold and less than a second threshold, it is determined that the sensor is degraded. If a pressure waveform within the predetermined threshold range is not acquired from at least any of the multiple sensors, or if pressure waveforms within the predetermined threshold range are acquired from all of the multiple sensors, and the difference between multiple static pressure waveforms based on the acquired pressure waveforms is equal to or greater than the second threshold, it is determined that the sensor is broken. This makes it possible to more easily and accurately determine sensor deterioration and failure.

[0105] Furthermore, if pressure waveforms within a predetermined threshold range are acquired from all of the multiple sensors, and the difference between multiple dynamic pressure waveforms based on the acquired pressure waveforms is equal to or greater than a third threshold and less than a fourth threshold, it is determined that the sensor is degraded. If a pressure waveform within the predetermined threshold range is not acquired from at least any of the multiple sensors, or if pressure waveforms within the predetermined threshold range are acquired from all of the multiple sensors, and the difference between multiple dynamic pressure waveforms based on the acquired pressure waveforms is equal to or greater than a fourth threshold, it is determined that the sensor is broken. This makes it possible to more easily and accurately determine sensor degradation and failure.

[0106] Furthermore, when pressure waveforms within a predetermined threshold range are acquired from all of the multiple sensors, and the difference between the multiple static pressure waveforms based on the acquired multiple pressure waveforms is equal to or greater than a first threshold and less than a second threshold, it is determined that the static pressure measurement function of the sensor has deteriorated. When no pressure waveform within the predetermined threshold range is acquired from at least any of the multiple sensors, or when pressure waveforms within the predetermined threshold range are acquired from all of the multiple sensors, and the difference between the multiple static pressure waveforms based on the acquired multiple pressure waveforms is equal to or greater than a second threshold, it is determined that the static pressure measurement function of the sensor has malfunctioned. This makes it possible to more easily and accurately determine the deterioration and malfunction of the static pressure measurement function of the sensor.

[0107] Furthermore, when the pressure waveforms within a predetermined threshold range are acquired from all of the multiple sensors, and the difference between multiple dynamic pressure waveforms based on the acquired multiple pressure waveforms is equal to or greater than a third threshold and less than a fourth threshold, it is determined that the dynamic pressure measurement function of the sensor has deteriorated, If no pressure waveform within the predetermined threshold range is acquired from at least any of the multiple sensors, or if pressure waveforms within the predetermined threshold range are acquired from all of the multiple sensors and the difference between multiple dynamic pressure waveforms based on the acquired multiple pressure waveforms is equal to or greater than a fourth threshold, it is determined that the dynamic pressure measurement function of the sensor is broken. This makes it possible to more easily and accurately determine the deterioration and failure of the static pressure measurement function of the sensor. In addition, the time from the point in time when it is determined that the sensor is deteriorated or broken is measured and recorded. This makes it possible to easily obtain information for, for example, further effectively improving the accuracy of determining the deterioration and failure of the sensor.

[0108] Furthermore, at least one of deterioration and failure of the sensor is judged continuously, intermittently, or when an instruction for judgment is received, whereby deterioration and failure of the sensor can be judged flexibly and efficiently.

[0109] In addition, the presence or absence of a power supply failure is determined based on the power supply voltage measured by the power supply voltage measurement unit, and when it is determined that there is no power supply failure, at least one of deterioration and failure of the sensor is determined. This makes it possible to prevent a decrease in the accuracy of determining deterioration and failure of the sensor caused by a power supply failure.

[0110] In addition, at least one of deterioration and failure of the sensor is determined based on the temperature and humidity measured by the temperature and humidity measuring unit, thereby making it possible to suppress a decrease in accuracy of determining deterioration and failure of the sensor caused by fluctuations in temperature and humidity.

[0111] Furthermore, when a state in which the difference between the multiple static pressure waveforms based on the multiple pressure waveforms is equal to or greater than a first threshold value and less than a second threshold value continues for a predetermined first time, it is determined that the difference between the multiple static pressure waveforms is equal to or greater than the first threshold value and less than the second threshold value. Then, when a state in which the difference between the multiple static pressure waveforms based on the multiple pressure waveforms is equal to or greater than the second threshold value continues for a predetermined second time, it is determined that the difference between the multiple static pressure waveforms is equal to or greater than the second threshold value. This makes it possible to suppress deterioration of the sensor and a decrease in the accuracy of failure determination due to temporary instability of the acquired pressure waveforms, etc.

[0112] Furthermore, when a state in which the difference between the multiple dynamic pressure waveforms based on the multiple pressure waveforms is equal to or greater than the third threshold and less than the fourth threshold continues for a predetermined third time, it is determined that the difference between the multiple dynamic pressure waveforms is equal to or greater than the third threshold and less than the fourth threshold. Then, when a state in which the difference between the multiple dynamic pressure waveforms based on the multiple pressure waveforms is equal to or greater than the fourth threshold continues for a predetermined fourth time, it is determined that the difference between the multiple dynamic pressure waveforms is equal to or greater than the fourth threshold. This makes it possible to suppress deterioration of the sensor and a decrease in the accuracy of failure determination due to temporary instability of the acquired pressure waveforms, etc.

[0113] The present invention also includes a notification unit that notifies at least one of the determined deterioration and failure of the sensor, thereby making it possible to easily and quickly notify the occurrence of deterioration and failure of the sensor.

[0114] Although the biological information measuring device 300, the biological information measuring method, and the biological information measuring program according to the embodiment of the present invention have been described above, the present invention is not limited to the above-described embodiment.

[0115] For example, in the flowchart of FIG. 6, steps S202 and S204 may be omitted, and when it is determined in step S201 that none of the sensor signals are outside the design range (S201: NO), steps S203 and S204 may be executed in parallel.

[0116] Furthermore, if the first sensor 311 and the second sensor 312 are sensors that cannot measure static pressure (if all of the sensors installed in the biological information measuring system 10 are sensors that cannot measure static pressure), steps S202 to S207 may be omitted in the flowchart of FIG. 6.

[0117] Furthermore, in the above-described embodiment, some or all of the functions executed by the biological information measurement program may be executed by hardware such as an electronic circuit.

[0118] The configuration of the biological information measuring method and the biological information measuring program according to the present invention includes the following.

[0119] (1) A method for measuring biological information comprising: an acquisition step of acquiring signals related to the measured pressure from a plurality of sensors connected to an air bag containing air, each of the sensors measuring the pressure the air bag receives from a subject; and a determination step of determining at least one of deterioration and failure of at least one of the sensors based on the plurality of pressure-related signals acquired from the plurality of sensors.

[0120] (2) A biological information measuring method as described in (1) above, in which the pressure-related signal is a pressure waveform, and in the judgment step, at least one of deterioration and failure of the sensor is judged based on the difference between values ​​of multiple of the pressure waveforms.

[0121] (3) The biological information measuring method described above in (1), wherein the plurality of sensors are two different types of sensors.

[0122] (4) The biological information measuring method described in (1) above, wherein the pressure-related signal is a pressure waveform, and in the determination step, if pressure waveforms within a predetermined threshold range are acquired from all of the multiple sensors and a difference between multiple static pressure waveforms based on each of the acquired pressure waveforms is greater than or equal to a first threshold and less than a second threshold, it is determined that the sensor is degraded, and if the pressure waveform within the predetermined threshold range is not acquired from at least any of the multiple sensors, or the pressure waveforms within the predetermined threshold range are acquired from all of the multiple sensors and a difference between multiple static pressure waveforms based on each of the acquired pressure waveforms is greater than or equal to the second threshold, it is determined that the sensor is faulty.

[0123] (5) The biological information measuring method described in (1) above, wherein the pressure-related signal is a pressure waveform, and in the determination step, if the pressure waveforms within a predetermined threshold range are acquired from all of the multiple sensors and the difference between multiple dynamic pressure waveforms based on each of the acquired multiple pressure waveforms is greater than or equal to a third threshold and less than a fourth threshold, it is determined that the sensor is degraded, and if the pressure waveform within the predetermined threshold range is not acquired from at least any of the multiple sensors, or the pressure waveforms within the predetermined threshold range are acquired from all of the multiple sensors and the difference between multiple dynamic pressure waveforms based on each of the acquired multiple pressure waveforms is greater than or equal to the fourth threshold, it is determined that the sensor is faulty.

[0124] (6) In the determination step, if pressure waveforms within the predetermined threshold range are acquired from all of the multiple sensors and the difference between multiple static pressure waveforms based on each of the acquired multiple pressure waveforms is greater than or equal to a first threshold and less than a second threshold, it is determined that the static pressure measurement function of the sensor has deteriorated, and if the pressure waveform within the predetermined threshold range is not acquired from at least any of the multiple sensors, or the pressure waveforms within the predetermined threshold range are acquired from all of the multiple sensors and the difference between multiple static pressure waveforms based on each of the acquired multiple pressure waveforms is greater than or equal to the second threshold, it is determined that the static pressure measurement function of the sensor has malfunctioned.

[0125] (7) In the determination step, if pressure waveforms within a predetermined threshold range are acquired from all of the multiple sensors and the difference between multiple dynamic pressure waveforms based on each of the acquired multiple pressure waveforms is greater than or equal to a third threshold and less than a fourth threshold, it is determined that the dynamic pressure measurement function of the sensor has deteriorated, and if the pressure waveform within the predetermined threshold range is not acquired from at least any of the multiple sensors, or the pressure waveforms within the predetermined threshold range are acquired from all of the multiple sensors and the difference between multiple dynamic pressure waveforms based on each of the acquired multiple pressure waveforms is greater than or equal to the fourth threshold, the dynamic pressure measurement function of the sensor is determined to have malfunctioned.

[0126] (8) The biological information measuring method described in (1) above, further comprising an abnormality occurrence time measuring step of measuring and recording the time from the point at which the sensor is determined to be deteriorated or broken in the judgment step.

[0127] (9) The biological information measuring method described in (1) above, in which the judgment step judges at least one of deterioration and failure of the sensor continuously, intermittently, or when an instruction for judgment is received.

[0128] (10) A method for measuring biological information as described in (1) above, comprising a power supply voltage measurement step for measuring the voltage of a power supply, and in the determination step, determining whether or not the power supply is faulty based on the voltage of the power supply measured in the power supply voltage measurement step, and if it is determined that the power supply is not faulty, determining at least one of deterioration and failure of the sensor.

[0129] (11) A method for measuring biological information as described in (1) above, comprising a temperature and humidity measurement step for measuring temperature and humidity, and in the judgment step, judging at least one of deterioration and failure of the sensor based on the temperature and humidity measured in the temperature and humidity measurement step.

[0130] (12) In the judgment step, if a state in which the difference between the multiple static pressure waveforms based on the multiple acquired pressure waveforms is greater than or equal to the first threshold and less than the second threshold continues for a predetermined first time, it is judged that the difference between the multiple static pressure waveforms is greater than or equal to the first threshold and less than the second threshold, and if a state in which the difference between the multiple static pressure waveforms based on the multiple acquired pressure waveforms is greater than or equal to the second threshold continues for a predetermined second time, it is judged that the difference between the multiple static pressure waveforms is greater than or equal to the second threshold.

[0131] (13) In the judgment step, if a state in which the difference between the multiple dynamic pressure waveforms based on the multiple acquired pressure waveforms is greater than or equal to the third threshold and less than the fourth threshold continues for a predetermined third time, it is judged that the difference between the multiple dynamic pressure waveforms is greater than or equal to the third threshold and less than the fourth threshold, and if a state in which the difference between the multiple dynamic pressure waveforms based on the multiple acquired pressure waveforms is greater than or equal to the fourth threshold continues for a predetermined fourth time, it is judged that the difference between the multiple dynamic pressure waveforms is greater than or equal to the fourth threshold.

[0132] (14) The biological information measuring method according to (1) above, further comprising a notification step of notifying at least one of the deterioration and the failure of the sensor determined in the determination step.

[0133] (15) A biological information measuring program for causing a computer to execute the biological information measuring method according to any one of (1) to (14) above. [Explanation of symbols]

[0134] 100 mattresses, 110 beds, 120 subjects, 210 Matt, 220 tube, 300 Biometric information measuring device, 311 First sensor, 312 second sensor, 320A first signal processing unit, 321A 1st amplifier circuit, 322A HPF, 323A Second amplifier circuit, 324A LPF, 320B second signal processing unit, 321B 3rd amplifier circuit, 322B HPF, 323B 4th amplifier circuit, 324B LPF, 330 A / D conversion section, 335 Transmitting unit, 340 Analysis Department, 341 CPU, 342 ROMs, 343 RAM, 344 Input / Output Interface, 345 Analysis unit / Transmission and reception analysis unit, 350 System Department, 351 Transmission unit, 352 Operation display section, 353 Records Division, 400 terminal equipment.

Claims

1. an acquisition unit that is connected to an air bag containing air and acquires signals related to the measured pressure from a plurality of sensors that measure pressures that the air bags receive from a subject; a determination unit that determines at least one of deterioration and failure of at least one of the sensors based on a plurality of pressure-related signals acquired from the plurality of sensors; A vital sign measuring system having the above structure.

2. the pressure-related signal is a pressure waveform; The biological information measuring system according to claim 1 , wherein the determining unit determines at least one of deterioration and failure of the sensor based on a difference between values ​​of a plurality of the pressure waveforms.

3. The plurality of sensors are provided. The biological information measuring system according to claim 1 , wherein the plurality of sensors are two different types of sensors.

4. the pressure-related signal is a pressure waveform; The determination unit is When the pressure waveforms within a predetermined threshold range are acquired from all of the plurality of sensors, and a mutual difference between a plurality of static pressure waveforms based on each of the acquired plurality of pressure waveforms is equal to or greater than a first threshold value and less than a second threshold value, it is determined that the sensor is deteriorated; 2. The bioinformation measuring system of claim 1, wherein the sensor is determined to be faulty when the pressure waveform within the predetermined threshold range is not acquired from at least any of the plurality of sensors, or when the pressure waveform within the predetermined threshold range is acquired from all of the plurality of sensors and the difference between the plurality of static pressure waveforms based on the acquired plurality of pressure waveforms is equal to or greater than the second threshold value.

5. the pressure-related signal is a pressure waveform; The determination unit is When the pressure waveforms within a predetermined threshold range are acquired from all of the plurality of sensors, and a mutual difference between a plurality of dynamic pressure waveforms based on the acquired plurality of pressure waveforms is equal to or greater than a third threshold and less than a fourth threshold, it is determined that the sensor is deteriorated; The bioinformation measuring system of claim 1, wherein the sensor is determined to be malfunctioning when the pressure waveform within the predetermined threshold range is not acquired from at least any of the plurality of sensors, or when the pressure waveform within the predetermined threshold range is acquired from all of the plurality of sensors and the difference between the plurality of dynamic pressure waveforms based on the acquired plurality of pressure waveforms is equal to or greater than the fourth threshold value.

6. The determination unit is When the pressure waveforms within the predetermined threshold range are acquired from all of the plurality of sensors, and a mutual difference between a plurality of static pressure waveforms based on each of the acquired plurality of pressure waveforms is equal to or greater than a first threshold value and less than a second threshold value, it is determined that the static pressure measurement function of the sensor has deteriorated; 5. The bioinformation measuring system of claim 4, wherein if the pressure waveform within the predetermined threshold range is not acquired from at least any of the plurality of sensors, or if the pressure waveform within the predetermined threshold range is acquired from all of the plurality of sensors and the difference between the plurality of static pressure waveforms based on the acquired plurality of pressure waveforms is equal to or greater than the second threshold, it is determined that the static pressure measurement function of the sensor is malfunctioning.

7. The determination unit is if pressure waveforms within a predetermined threshold range are acquired from all of the plurality of sensors, and a difference between a plurality of dynamic pressure waveforms based on each of the acquired plurality of pressure waveforms is equal to or greater than a third threshold and less than a fourth threshold, it is determined that the dynamic pressure measurement function of the sensor has deteriorated; The biological information measuring system of claim 5, wherein if the pressure waveform within the predetermined threshold range is not acquired from at least any of the plurality of sensors, or if the pressure waveform within the predetermined threshold range is acquired from all of the plurality of sensors and the difference between the plurality of dynamic pressure waveforms based on the acquired plurality of pressure waveforms is equal to or greater than the fourth threshold, it is determined that the dynamic pressure measurement function of the sensor is malfunctioning.

8. 2. The biological information measuring system according to claim 1, further comprising an abnormality occurrence time measuring unit that measures and records the time from the point in time when the determining unit determines that the sensor is deteriorated or broken.

9. The biological information measuring system according to claim 1 , wherein the determination unit determines at least one of deterioration and failure of the sensor continuously, intermittently, or when an instruction for determination is received.

10. A power supply voltage measuring unit is provided for measuring a voltage of a power supply, 2. The biological information measuring system of claim 1, wherein the determination unit determines whether or not the power supply is faulty based on the voltage of the power supply measured by the power supply voltage measurement unit, and if it determines that the power supply is not faulty, determines at least one of deterioration and failure of the sensor.

11. A temperature and humidity measuring unit is provided for measuring temperature and humidity, The biological information measuring system according to claim 1 , wherein the determining unit determines at least one of deterioration and failure of the sensor based on the temperature and humidity measured by the temperature and humidity measuring unit.

12. The determination unit is When a state in which a mutual difference between a plurality of the static pressure waveforms based on the respective acquired plurality of pressure waveforms is equal to or greater than the first threshold value and less than the second threshold value continues for a predetermined first time, it is determined that the mutual difference between the plurality of the static pressure waveforms is equal to or greater than the first threshold value and less than the second threshold value, The biological information measuring system of claim 4, wherein when a state in which a difference between a plurality of the static pressure waveforms based on each of the acquired plurality of pressure waveforms is greater than or equal to the second threshold continues for a predetermined second time period, the difference between the plurality of the static pressure waveforms is determined to be greater than or equal to the second threshold.

13. The determination unit is when a state in which a mutual difference between a plurality of the dynamic pressure waveforms based on the respective acquired plurality of the pressure waveforms is equal to or greater than the third threshold value and less than the fourth threshold value continues for a predetermined third time, it is determined that the mutual difference between the plurality of the dynamic pressure waveforms is equal to or greater than the third threshold value and less than the fourth threshold value; The biological information measuring system of claim 5, wherein when a state in which a difference between multiple dynamic pressure waveforms based on each of the acquired multiple pressure waveforms is greater than or equal to the fourth threshold continues for a predetermined fourth time period, the difference between multiple dynamic pressure waveforms is determined to be greater than or equal to the fourth threshold.

14. 2. The biological information measuring system according to claim 1, further comprising a notification unit that notifies at least one of deterioration and a failure of the sensor determined by the determination unit.

15. an acquiring step of acquiring signals related to the measured pressure from a plurality of sensors connected to an air bag containing air and each measuring a pressure applied to the air bag by a subject; a determining step of determining at least one of deterioration and failure of at least one of the sensors based on a plurality of pressure-related signals acquired from the plurality of sensors; The biological information measuring method includes the steps of:

16. an acquiring step of acquiring signals related to the measured pressure from a plurality of sensors connected to an air bag containing air and each measuring a pressure applied to the air bag by a subject; a determining step of determining at least one of deterioration and failure of at least one of the sensors based on a plurality of pressure-related signals acquired from the plurality of sensors; A biometric measurement program for causing a computer to execute the above.

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