Patent Application
20250102536
The present invention relates to a determination system, a determination method, a determination device and a determination program in order to determine a state of a subject person.
In a facility such as a hospital, a nursing home or a nursing facility, a person in charge (a nurse or a caregiver) looks around the facility to confirm the state of each care recipient (a patient or a resident), for example, whether he/she is in the bed in a patient room or getting out from the bed. In order to support such a patrol work, the Applicant of the present invention has proposed, for example, a living body detection system using a piezoelectric sheet so as to be placed on a bed, which detects whether a care recipient is present or not (see, for example, Patent Document 1).
Patent Document 1 proposes an excellent living body detection system. However, for the purpose of further enriching the quality of care and/or nursing care, now there is a demand for determining how the state of a subject person such as a care recipient is.
The present invention was made in consideration of the above circumstances, a principal object of which is to provide a determination system to determine a state of a subject person.
Also, another object of the present invention is to provide a determination method using the determination system of the present invention.
Furthermore, another object of the present invention is to provide a determination device used in the determination system of the present invention.
Furthermore, another object of the present invention is to provide a determination program to realize the determination device of the present invention.
In order to solve the above problem, a determination system disclosed in the present invention includes: a detection section detecting a wave motion generated by a subject person and outputting an electrical signal based on the detected wave motion; and a determination section determining that the subject person starts a get-up motion when a signal value of the electrical signal that is output from the detection section satisfies a state determination condition that a period of time when the signal value is not less than a predetermined upper limit threshold value or not more than a predetermined lower limit threshold value exceeds a predetermined time threshold value.
Also in the above-described determination system, the determination section determines that the subject person starts the get-up motion in which a body position of the subject person moves from a lying position to a sitting position when the body position of the subject person satisfies the state determination condition from a state in which it is determined that the subject person is in the lying position.
Also in the above-described determination system, the signal value is a value according to a signal waveform that maintains a shape of a waveform of the electrical signal output from the detection section.
Also in the above-described determination system, the signal value is a value obtained by removing hum noise from the electrical signal output from the detection section.
Also in the above-described determination system, the signal value is a value according to a signal waveform that is obtained by transmitting an electrical signal in a frequency band of 4 Hz or less out of electrical signals output from the detection section.
Also in the above-described determination system, the signal value is a value as a moving average of electrical signals output from the detection section, and the moving average is taken for the period of 5 seconds or less.
Also in the above-described determination system, the electrical signal output from the detection section is an analog electrical signal, and the signal value is a value according to a digital electrical signal converted from the analog electrical signal.
Also in the above-described determination system, the detection section includes a piezoelectric sensor formed in a sheet shape.
Also, a determination method disclosed in the present invention includes the steps of: detecting a wave motion generated by a subject person and thus outputting an electrical signal based on the detected wave motion, which are performed by a detection section; and determining whether a signal value of the electrical signal that is output from the detection section satisfies or not a state determination condition that a period of time when the signal value is not less than a predetermined upper limit threshold value or not more than a predetermined lower limit threshold value exceeds a predetermined time threshold value.
Also in the above-described determination method, it is determined that the subject person starts the get-up motion in which a body position of the subject person moves from a lying position to a sitting position when the body position of the subject person satisfies the state determination condition from a state in which it is determined that the subject person is in the lying position.
Also in the above-described determination method, the signal value is a value according to a signal waveform that maintains a shape of a waveform of the electrical signal output from the detection section.
Also in the above-described determination method, the signal value is a value obtained by removing hum noise from the electrical signal output from the detection section.
Also in the above-described determination method, the signal value is a value according to a signal waveform that is obtained by transmitting an electrical signal in a frequency band of 4 Hz or less out of electrical signals output from the detection section.
Also in the above-described determination method, the signal value is a value as a moving average of electrical signals output from the detection section, and the moving average is taken for the period of 5 seconds or less.
Also in the above-described determination method, the electrical signal output from the detection section is an analog electrical signal, and the signal value is a value according to a digital electrical signal converted from the analog electrical signal.
Also in the above-described determination method, the detection section includes a piezoelectric sensor formed in a sheet shape.
Also, a determination device disclosed in the present invention includes: an input section receiving input of an electrical signal based on detection of a wave motion generated by a subject person; and a determination section determining whether a signal value of the electrical signal that is received by the input section satisfies or not a state determination condition that a period of time when the signal value is not less than a predetermined upper limit threshold value or not more than a predetermined lower limit threshold value exceeds a predetermined time threshold value.
Also in the above-described determination device, the determination section determines that the subject person starts the get-up motion in which a body position of the subject person moves from a lying position to a sitting position when the body position of the subject person satisfies the state determination condition from a state in which it is determined that the subject person is in the lying position.
Also in the above-described determination device, the signal value is a value according to a signal waveform that maintains a shape of a waveform of the electrical signal received by the input section.
Also in the above-described determination device, the signal value is a value obtained by removing hum noise from the electrical signal received by the input section.
Also in the above-described determination device, the signal value is a value according to a signal waveform that is obtained by transmitting an electrical signal in a frequency band of 4 Hz or less out of electrical signals received by the input section.
Also in the above-described determination device, the signal value is a value as a moving average of electrical signals received by the input section, and the moving average is taken for the period of 5 seconds or less.
Also in the above-described determination device, the electrical signal received by the input section is an analog electrical signal, and the signal value is a value according to a digital electrical signal converted from the analog electrical signal.
Also, a determination program disclosed in the present invention is to cause a computer to determine a state of a subject person. The determination program includes the steps, performed by the computer, of: receiving input of a signal value based on a wave motion generated by the subject person; and determining whether the input signal value satisfies or not a state determination condition that a period of time when the signal value is not less than a predetermined upper limit threshold value or not more than a predetermined lower limit threshold value exceeds a predetermined time threshold value.
Also in the determination step in the above-described determination program, it is determined that the subject person starts the get-up motion in which a body position of the subject person moves from a lying position to a sitting position when the body position of the subject person satisfies the state determination condition from a state in which it is determined that the subject person is in the lying position.
Also in the above-described determination program, the signal value is a value according to a signal waveform that maintains a shape of a waveform of the electrical signal received in the input step.
Also in the above-described determination program, the signal value is a value obtained by removing hum noise from the electrical signal received in the input step.
Also in the above-described determination program, the signal value is a value according to a signal waveform that is obtained by transmitting an electrical signal in a frequency band of 4 Hz or less out of electrical signals received in the input step.
Also in the above-described determination program, the signal value is a value as a moving average of electrical signals received in the input step, and the moving average is taken for the period of 5 seconds or less.
Also in the above-described determination program, the electrical signal received in the input step is an analog electrical signal, and the signal value is a value according to a digital electrical signal converted from the analog electrical signal.
The determination system, the determination method, the determination device and the determination program of the present invention provide excellent effects such as a capability to determine a state of a subject person.
A determination system disclosed in the present invention is a system using various devices such as a detection device and a determination device, and is used for the purpose of detecting a state of a subject person, for example, a breathing status, a heartbeat status, and a posture status. Examples of the posture status include a lying position and a sitting position. The present invention is mainly applied to detection of an initial motion of the subject person to move from the lying position to the sitting position, i.e. a starting state of a get-up motion. Hereinafter, specific examples of devices exemplarily shown in the drawings (such as a detection device 1 and a determination device 2) will be described with reference to the drawings.
Note that the embodiment described below is an example to realize the present invention, and thus it does not limit the technical scope of the present invention.
The bed 3 used by the care recipient has a bedstead 30. A mattress 31 as bedding is placed on the bedstead 30. A sheet or the like as bedding is also put, as needed, on the mattress 31. A detection device 1 is attached onto the bed 3. The detection device 1 includes a detection section 10 made of a sheet-shaped piezoelectric sensor 10a (see
The detection device 1 is connected to the determination device 2. The electrical signal that is output from the detection device 1 is input into the determination device 2 via a communication line. The detection device 1 and the determination device 2 may communicate with each other by wireless communication based on a wireless communication standard such as Bluetooth (registered trademark).
As devices capable of communicating with the determination device 2, various kinds of communication devices 4 are used, which include: a nurse call receiver carried by a nurse; a monitor equipped in the nurse's station; and a mobile phone, a smartphone and a tablet type device that are carried by an external person involved. The determination device 2 and the communication device 4 are communicably connected to each other via a communication network NW such as a wireless LAN (local area network), a wired LAN, a WAN (wide area network), or a dedicated communication line. The determination device 2 transmits various kinds of information such as notification information by determination processing and the like (described later) to the communication device 4 via the communication network NW. The transmission of the various kinds of information from the determination device 2 to the communication device 4 may be a push notification that sends information in substantially real time, or may be a pull notification that accumulates information on a data server on the communication network NW so that the communication device 4 acquires such accumulated pieces of information as necessary. Furthermore, it is possible to develop many other modes such as using the push notification together with the pull notification. The information such as notification information described in the present invention is transmitted by the push notification, since immediacy is required in the present case.
Here, hardware configurations of the respective devices provided in the determination system disclosed in the present invention will be described.
The detection section 10 has a function to detect, by the piezoelectric sensor 10a, a wave motion such as sound and vibration, and to convert the detected wave motion into an analog electrical signal so as to output the analog electrical signal to the amplitude amplifier 11.
Now referring to the block diagram of
The output section 13 outputs the analog electrical signal that is allowed to pass through the pre-processing LPF 12 to the determination device 2.
The amplitude amplifier 11 and the pre-processing LPF 12 are each a circuit to perform pre-processing to an input electrical signal such that the input electrical signal becomes an electrical signal capable of being processed by the determination device 2. The shape of the waveform of the electrical signal is substantially maintained after the amplitude amplification and the removal of the high frequency noise. That is, the detection device 1 outputs, to the determination device 2, the electrical signal having a signal waveform as so-called “raw data” detected by the detection section 10.
The input section 20 is an input unit to receive input of the analog electrical signal that is output from the detection device 1.
The signal processing section 21 is a unit that performs or does not perform processing to the received electrical signal so as to output the processed/unprocessed electrical signal to the determination section 22. The signal processing section 21 is provided with an A/D conversion section 210 that converts the analog electrical signal received by the input section 20 into a digital electrical signal, and also includes a plurality of routes to process the converted digital electrical signal. The A/D conversion section 210 samples the analog electrical signal at a sampling period of, for example, 100 Hz so as to convert the analog electrical signal into the digital electrical signal.
A first route 21a is a route for performing signal processing to detect the heartbeat signal of the subject person. The first route 21a includes circuits such as a detection circuit 21a1, an HPF (high pass filter) circuit 21a2, and a first LPF circuit 21a3. The HPF circuit 21a2 removes, for example, the electrical signals in the frequency band of 0.01 Hz or less. It is more preferable that the HPF circuit 21a2 removes the electrical signals in the frequency band of 0.6 Hz or less. When the HPF circuit 21a2 removes the electrical signals in the frequency band of 0.01 Hz or less, it allows the electrical signals in the frequency band exceeding 0.01 Hz to pass through. When the HPF circuit 21a2 removes the electrical signals in the frequency band of 0.6 Hz or less, it allows the electrical signals in the frequency band of 0.6 Hz or less to pass through. The first LPF circuit 21a3 removes, for example, the electrical signals in the frequency band exceeding 4.0 Hz. It is more preferable that the first LPF circuit 21a3 removes the electrical signals in the frequency band exceeding 2.2 Hz. When the first LPF circuit 21a3 removes the electrical signals in the frequency band exceeding 4.0 Hz, it allows the electrical signals in the frequency band of 4.0 Hz or less to pass through. When the first LPF circuit 21a3 removes the electrical signals in the frequency band exceeding 2.2 Hz, it allows the electrical signals in the frequency band of 2.2 Hz or less to pass through. The electrical signal that passes through the first route 21a is output to the determination section 22.
A second route 21b is a route for performing signal processing to detect that the subject person is in the middle of doing the get-up motion or that the get-up motion has been finished. The second route 21b includes circuits such as a second LPF circuit 21b1 and a detection circuit 21b2. The second LPF circuit 21b1 removes, for example, the electrical signals in the frequency band exceeding 10 Hz. It is more preferable that the second LPF circuit 21b1 removes the electrical signals in the frequency band exceeding 1 Hz. When the second LPF circuit 21b1 removes the electrical signals in the frequency band exceeding 10 Hz, it allows the electrical signals in the frequency band of 10 Hz or less to pass through. When the second LPF circuit 21b1 removes the electrical signals in the frequency band exceeding 1 Hz, it allows the electrical signals in the frequency band of 1 Hz or less to pass through. The electrical signal that passes through the second route 21b is output to the determination section 22.
The third route 21c is a route for performing signal processing to detect the breathing signal of the subject person. The third route 21c includes circuits such as a third LPF circuit 21c1. The third LPF circuit 21c1 removes, for example, the electrical signals in the frequency band exceeding 2.0 Hz. It is more preferable that the third LPF circuit 21cl removes the electrical signals in the frequency band exceeding 0.5 Hz. When the third LPF circuit 21cl removes the electrical signals in the frequency band exceeding 2.0 Hz, it allows the electrical signals in the frequency band of 2.0 Hz or less to pass through. When the third LPF circuit 21cl removes the electrical signals in the frequency band exceeding 0.5 Hz, it allows the electrical signals in the frequency band of 0.5 Hz or less to pass through. The electrical signal that passes through the third route 21c is output to the determination section 22.
The fourth route 21d is a route for performing signal processing to detect that the subject person starts the get-up motion in which the body position of the subject person moves from the lying position to the sitting position. The fourth route 21d outputs the received electrical signal to the determination section 22 without performing any processing. The electrical signal that passes through the fourth route 21d is an electrical signal that maintains the shape of the waveform of the digital electrical signal converted by the A/D conversion section 210. Each of the various circuits provided in the signal processing section 21 can be configured by hardware or software, or can also be configured as a hybrid circuit of hardware and software.
The determination section 22 is made by using a microcomputer that is provided with a semiconductor chip such as a VLSI (very large-scale IC). The determination section 22 includes sections such as a control section 220, a recording section 221, an output section 222, and a communication section 223.
The control section 220 includes various circuits such as an information processing circuit, a timing circuit, and a register circuit. The control section 220 is a processor that executes overall control processing.
The recording section 221 is a circuit configured using a non-volatile memory and a volatile memory so as to record various kinds of data such as programs and threshold values. Examples of the programs recorded in the recording section 221 include a determination program 221a to perform determination processing. Examples of the threshold values recorded in the recording section 221 include various threshold values such as an upper limit threshold value, a lower limit threshold value, and a time threshold value, which are used in determination processing.
The control section 220 executes respective steps included in the determination program 221a recorded in the recording section 221. Thus, the determination device 2 functions to determine the state of the subject person by the digital electrical signal based on the wave motion detected by the detection section 10.
The output section 222 is an output unit such as a liquid crystal display or a speaker.
The communication section 223 is a communication unit including respective components such as an antenna, a LAN adapter, a control circuit and the like. The communication section 223 performs a wireless communication or a wired communication with the communication device 4 via the communication network NW.
The communication device 4 includes sections such as a communication section 40 that performs communication with the determination device 2 via the communication network NW, and an output section 41 that performs respective outputs. Examples of the outputs from the output section 41 include: light output; image display; audio output; ringing; and vibrating.
Here, processing of the respective devices in the determination system disclosed in the present invention will be described.
As described above, the detection device 1 performs the detection processing.
As described above, the detection device 1 performs the signal processing.
The control section 220 provided in the determination section 22 of the determination device 2 performs the determination processing by executing the determination program 221a recorded in the recording section 221. The control section 220 calculates the moving average value of the signal values of the received digital electrical signals that passed through the fourth route 21d (S301). In step S301, the moving average value is calculated, for example, for the period of 5 seconds or less. Regarding the determination of the start of the get-up motion, it is not preferable to prolong the target period for the moving average because in this case the immediacy is required. Also, in the case of the determination processing where the immediacy is considered to be important, the calculation of the moving average in step S301 may be omitted to execute the processing in step 302 and thereafter (described below). In other words, the processing in step S301 is performed when the immediacy is not particularly required, and the higher the request for immediacy becomes, the shorter the target period should be. Thus, when the immediacy is considered to be important, it is preferable to use the signal value of the digital electrical signal without calculating the moving average.
The control section 220 determines whether the state of the subject person is in the lying position or not (i.e. whether the subject person maintains the lying state on the bed 3 or not) (S302). The determination itself on whether the subject person is in the lying position or not is executed based on the digital electrical signals that pass through the other routes such as the first route 21a. In step S302, the method for determining the lying position is used, which is described, for example, in WO 2021/112131 filed by the Applicant of the present application.
When it is determined that the state of the subject person is in the lying position in step S302 (S302: YES), the control section 220 determines whether the signal value of the digital electrical signal is not less than a predetermined upper limit threshold value or not more than a predetermined lower limit threshold value referring to the recording section 221 (S303). The upper limit threshold value and the lower limit threshold value are recorded in advance in the recording section 221 as the state determination condition.
When it is determined that the signal value is not less than the predetermined upper limit threshold value or not more than the predetermined lower limit threshold value in step S303 (S303: YES), the control section 220 determines whether the duration of time when the signal value is maintained to be not less than the upper limit threshold value or not more than the lower limit threshold value exceeds a time threshold value recorded in the recording section 221 (S304). In step S304, sometimes the signal value fluctuates momently due to noise or the like. Therefore, even when the signal value becomes momently less than the predetermined upper limit threshold value and also more than the predetermined lower limit threshold value from the state not less than the predetermined upper limit threshold value or not more than the predetermined lower limit threshold value, the control section 220 may be set to determine that the state of the signal value is maintained to be not less than the upper limit threshold value or not more than the lower limit threshold value under the condition that the signal value is not more than a predetermined momentary threshold value. Similarly to the above, when the signal value momently switches from the state not less than the upper limit threshold value to the state not more than the lower limit threshold value and furthermore when the signal value on the way to switch is detected, the control section 220 may be set to determine whether the state of the signal value is maintained to be not less than the upper limit threshold value or not more than the lower limit threshold value based on the momentary threshold value.
The threshold values as the state determination condition are recorded in advance in the recording section 221. The threshold values include: the upper limit threshold value and the lower limit threshold value as the criteria for determination in step S303; and the time threshold value and the momentary threshold value as the criteria for determination in step S304.
When it is determined that the duration of time when the signal value that is maintained to be not less than the upper limit threshold value or not more than the lower limit threshold value exceeds the time threshold value recorded in the recording section 221 in step S304 (S304: YES), the control section 220 determines that the state determination condition is satisfied and that the state of the subject person is a starting state of the get-up motion from the lying position to the sitting position (S305).
When it is determined that the state determination condition is satisfied and that the state of the subject person is the starting state of the get-up motion from the lying position to the sitting position, then the control section 220 performs notification processing to notify the start of the get-up motion (S306). The notification processing in step S306 includes: output processing that outputs the notification information to notify the start of the get-up motion from the output section 222; and transmission processing that transmits the notification information from the communication section 223 to the communication device 4 via the communication network NW. In step S306, recording processing may be performed to record, in the recording section 221, the fact that the state determination condition is satisfied, along with or in place of the notification processing.
The control section 220 determines that the state determination condition is not satisfied and that the state of the subject person is not the starting state of the get-up motion from the lying position to the sitting position (S307) in the following cases: when it is determined that the state of the subject person is not in the lying position in step S302 (S302: NO); when it is determined that the signal value is less than the upper limit threshold value and also more than the lower limit threshold value in step S303 (S303: NO); or when it is determined that the duration of time does not exceed the time threshold value in step S304 (S304: NO).
When it is determined that the state determination condition is not satisfied and the state of the subject person is not the starting state of the get-up motion from the lying position to the sitting position, then the control section 220 captures the signal value of the digital electrical signal as a next object to be determined, and returns to step S301 to repeatedly perform the processing in S301 and thereafter.
The determination processing of the determination device 2 is performed as described above. Here, the determination processing of the determination device 2 was explained, referring to
When the communication device 4 receives, by the communication section 40, the notification information transmitted from the determination device 2 via the communication network NW, the communication device 4 outputs, from the output section 41, the received notification information. The output of the notification information is performed as report processing such as light output, image display, audio output, ringing, and vibrating, from various kinds of communication devices 4 such as a nurse call receiver carried by a nurse, a monitor equipped in the nurse's station, and a mobile phone carried by an external person involved. Thus, since the staff such as nurses, caregivers and doctors and/or the persons involved such as families can confirm the notification information that is output from the communication device 4, they can take appropriate measures according to the state of the subject person.
Here, an embodiment of the determination system disclosed in the present invention is described.
As exemplarily shown in
As exemplarily shown in
The configuration of the determination system disclosed in the present invention is not limited to the configuration exemplarily shown in
As described above, the determination system according to System Configuration Variation 1 includes the independent signal processing device 5 having a function to process the signal originally performed by the determination device 2.
The configuration of the determination device 2 provided in the determination system disclosed in the present invention is not limited to the configuration exemplarily shown in
In Configuration Variation 1, the fourth route 21d includes a noise elimination circuit 21d1. The noise elimination circuit 21d1 is a circuit to remove hum noise of 10 Hz or more. By providing the noise elimination circuit 21d1 on the fourth route 21d, it is possible to improve determination accuracy and thus reduce erroneous determination of the determination device 2.
Each of Configuration Variations of the determination device 2 as described above (i.e. configuration in which the fourth route 21d is provided with the noise elimination circuit 21d1, the fourth LPF circuit 21d2 or the moving average circuit 21d3) may be appropriately combined to be embodied. More specifically, Configuration Variations of the determination device 2 may be variously embodied, for example, as configurations in which: the fourth route 21d is provided with the noise elimination circuit 21d1 and the fourth LPF circuit 21d2; the fourth route 21d is provided with the noise elimination circuit 21d1 and the moving average circuit 21d3; and the like.
As described above, the determination system disclosed in the present invention detects the wave motion of the subject person, and when the period of time in which the value representing the state is not less than the predetermined upper limit threshold value or not more than the predetermined lower limit threshold value exceeds the predetermined time threshold value, the determination system determines that the subject starts the get-up motion, and then performs notification. In this way, it is possible to exert an excellent effect of early detection of the start of the get-up motion that is likely to generate an accident, which makes it possible to take appropriate measures such as assistance.
The present invention should not be limited by the foregoing embodiments, and may be embodied in other forms without departing from the gist or essential characteristics thereof. Therefore, the embodiments described herein are to be considered in all respects as illustrative and not limiting. The scope of the present invention is indicated by the appended claims rather than by the foregoing embodiments, and all modifications and changes that come within the meaning and range of equivalency of the claims are intended to be embraced therein.
For example, in the forgoing embodiment, both of the upper limit threshold value and the lower limit threshold value are set as the state determination condition. However, the present invention may also be embodied in various way other than the above. For example, either the upper limit threshold value or the lower limit threshold value may only be set as the state determination condition.
Also in the foregoing embodiment, the duration of time in which the value representing the state is not less than the upper limit threshold value or not more than the lower limit threshold value is summed up to compare to the time threshold value. However, the present invention may also be embodied in various way other than the above. For example, the time threshold values may be set, respectively, with respect to the upper limit threshold value and the lower limit threshold value.
Also in the foregoing embodiment, the piezoelectric sensor 10a is used as the detection section 10 provided in the detection device 1. However, the present invention is not limited thereto. It is also possible to use various sensors such as a microphone sensor, provided that such a sensor can detect the wave motion.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-154639 | Sep 2021 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2022/034958 | 9/20/2022 | WO |
