Display control device, private booth, display method, and program

Abstract

This display control device comprises: an acquisition unit (34) that acquires body movement data of a user measured using a body movement sensor (20); and a display control unit (37) that displays, on a display device (50) in real time, a waveform of a signal related to heartbeats obtained from the acquired body movement data. While displaying the waveform of the signal related to the heartbeats on the display device (50) in real time, the display control unit (37) displays, on the display device (50), an example of a waveform of a signal related to heartbeats obtained when body movement data is correctly measured and an example of a waveform of a signal related to heartbeats obtained when body movement data is not correctly measured.

Description

Technical Field

[0001] The present invention relates to a display control device, a private booth, a display method, and a program.

Background Art

[0002] Patent Document 1 discloses an abnormality notification device that monitors biological information and issues a notification when an abnormality is detected.

Prior Art Literature

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] The present invention provides a display control device, a private booth, a display method, and a program that can support appropriate measurement of body movement data.

Means for Solving the Problem

[0005] A display control device according to one aspect of the present invention includes an acquisition unit that acquires user's body movement data measured by a sensor, and a display control unit that displays, on a display device in real time, a waveform of a signal related to a heartbeat obtained from the acquired body movement data. When the waveform of the signal related to the heartbeat is being displayed on the display device in real time, the display control unit displays, on the display device, an example of the waveform of the signal related to the heartbeat obtained when the body movement data is correctly measured, and an example of the waveform of the signal related to the heartbeat obtained when the body movement data is not correctly measured.

[0006] A private booth according to one aspect of the present invention includes the display control device, the sensor, a bed on which the sensor is provided, and the display device.

[0007] A private booth according to one aspect of the present invention comprises the display control device, the sensor, a chair on which the sensor is provided, and the display device.

[0008] A display method according to one aspect of the present invention is a display method performed by a computer, comprising: an acquisition step of acquiring user body movement data measured by a sensor; and a display step of displaying the waveform of a heart rate-related signal obtained from the acquired body movement data on a display device in real time, wherein in the display step, when the waveform of the heart rate-related signal is displayed on the display device in real time, an example of the waveform of the heart rate-related signal obtained when the body movement data is measured correctly and an example of the waveform of the heart rate-related signal obtained when the body movement data is not measured correctly are displayed on the display device.

[0009] A program according to one aspect of the present invention is a program that causes the computer to execute the display method described above. [Effects of the Invention]

[0010] The display control device, private booth, display method, and program of the present invention can support the appropriate measurement of body movement data. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 is an external view of the nap booth. [Figure 2] Figure 2 is a block diagram showing the functional configuration of a nap booth according to an embodiment. [Figure 3] Figure 3 is a flowchart of the support actions that assist in the proper measurement of body movement data. [Figure 4] Figure 4 shows an example of a BCG signal waveform. [Figure 5] Figure 5 is a flowchart showing the method for calculating the confidence level. [Figure 6] Figure 6 is a flowchart of the method for determining signal strength. [Figure 7] Figure 7 shows an example of a support image. [Modes for carrying out the invention]

[0012] The embodiments will be described below with reference to the drawings. Note that the embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, arrangement and connection configurations of components, steps, and the order of steps shown in the following embodiments are examples only and are not intended to limit the present invention. Furthermore, components in the following embodiments that are not described in an independent claim will be described as optional components.

[0013] Please note that each figure is a schematic diagram and not necessarily a strictly accurate representation. Furthermore, in each figure, substantially identical components are denoted by the same reference numerals, and redundant explanations may be omitted or simplified.

[0014] (Embodiment) [composition] First, the configuration of the nap booth according to the embodiment will be described. Figure 1 is an external view of the nap booth. Figure 2 is a block diagram showing the functional configuration of the nap booth according to the embodiment.

[0015] The nap booth 10 is a private room unit used by employees of medical facilities (hereinafter also referred to as users) to take naps during their shifts (such as night shifts). Inside the nap booth 10, a bed is provided, and the environment surrounding the user lying on the bed (brightness, temperature, scent, or airflow, etc.) is adjusted according to the user's sleep depth (in other words, sleep stage). In this way, the nap booth 10 is a device that can provide a comfortable sleep environment that makes it easy for the user to fall asleep and wake up. Specifically, the nap booth 10 is equipped with a body movement sensor 20, a control device 30, an environmental adjustment device 40, and a display device 50.

[0016] The body motion sensor 20 is a contact-type sensor that measures body motion data of a user lying on a bed. The body motion sensor 20 is a mat-shaped (in other words, sheet-shaped) sensor provided on the bed, and can measure the movement of the body surface of the user lying on the bed as body motion data. Note that the body motion sensor 20 measures the movement of the user's back to measure body motion data including a component derived from heartbeat. The body motion sensor 20 described here is merely an example, and any sensor that can measure body motion may be used regardless of its form. For example, the body motion sensor 20 may be a radio wave sensor that detects vibrations in a non-contact manner using radio waves, or may be a pressure sensor provided on the legs of a bed or a chair that can measure body motion data including a component derived from heartbeat. The body motion sensor 20 may also be an acceleration sensor installed on bedding.

[0017] The control device 30 estimates the user's sleep depth from a BCG (Ballistocardiogram) signal obtained from the body motion data measured by the body motion sensor 20, and controls the environment adjustment device 40 based on the estimated sleep depth. BCG is a term that refers to vibrations generated by the movement of blood vessels or the heart. The control device 30 is implemented by, for example, a personal computer or a tablet terminal, but may also be implemented as a dedicated device for the nap booth 10. The control device 30 includes a communication unit 31, an information processing unit 32, and a storage unit 33.

[0018] The communication unit 31 is a communication module (communication circuit) for the control device 30 to communicate with the body motion sensor 20, the environment adjustment device 40, and the display device 50. The communication performed by the communication unit 31 is, for example, wired communication, but may also be wireless communication. The communication standard used for the communication is also not particularly limited.

[0019] The information processing unit 32 is implemented by a processor or a microcomputer. The information processing unit 32 includes an acquisition unit 34 that acquires body motion data received by the communication unit 31, a calculation unit 35 that calculates a BCG signal from the acquired body motion data, a device control unit 36 that estimates sleep depth from parameters such as heart rate and respiratory rate obtained from the calculated BCG signal, and controls the environment adjustment device 40 based on the estimated sleep depth, and a display control unit 37 that performs control related to display of an image on the display device 50. The functions of the acquisition unit 34, the calculation unit 35, the device control unit 36, and the display control unit 37 are implemented by the processor or microcomputer constituting the information processing unit 32 executing the computer program stored in the storage unit 33.

[0020] The storage unit 33 is a storage device that stores various types of information used by the information processing unit 32, such as computer programs executed by the information processing unit 32. Specifically, the storage unit 33 is implemented by a semiconductor memory or the like.

[0021] The environment adjustment device 40 adjusts the environment around the user lying on the bed in the internal space of the nap booth 10. The environment adjustment device 40 includes at least one of a lighting device, an air conditioner, a scent generator, an airflow generator, and the like. The environment adjustment device 40 is not limited to these devices, and may be any device that adjusts the user's napping environment, such as a vibration applying device that rocks the bed. The environment adjustment device 40 is controlled by the device control unit 36.

[0022] The display device 50 is a display that displays an image visible to the user located in the internal space of the nap booth 10. The display device 50 is implemented by a display panel such as a liquid crystal panel or an organic EL panel. Note that the display device 50 may be included in the control device 30. For example, when the control device 30 is implemented as a tablet terminal, the display of the tablet terminal corresponds to the display device 50.

[0023] [Support operation for supporting appropriate measurement of body motion data] To accurately estimate sleep depth, it is necessary for the body movement sensor 20 to properly measure body movement data. The waveform of the body movement data is easily affected by the position of the user lying on the body movement sensor 20 (the positional relationship between the body movement sensor 20 and the user), but it is difficult for the user to adjust their body position so that the body movement data is properly measured.

[0024] Therefore, in the nap booth 10, the BCG signal obtained from the currently measured body movement data is displayed in real time on the display device 50 to help the user adjust their body position so that body movement data is measured appropriately. The following describes the support actions that assist in the proper measurement of body movement data. Figure 3 is a flowchart of the support actions that assist in the proper measurement of body movement data.

[0025] The communication unit 31 of the control device 30 receives user body movement data measured by the body movement sensor 20 from the body movement sensor 20 (S11), and the acquisition unit 34 acquires the received body movement data (S12).

[0026] The calculation unit 35 calculates a BCG signal from the acquired body movement data (S13). Specifically, the calculation unit 35 removes baseline fluctuations and noise by applying a bandpass filter to the body movement data. A bandpass filter is, for example, a filter whose passband is between 1 Hz and 40 Hz. The calculation unit 35 also calculates the BCG signal by performing various processes to emphasize the peaks originating from the heartbeat in the body movement data after applying the bandpass filter. Figure 4 shows an example of the waveform of the BCG signal. In Figure 4, the area enclosed by the dotted circle is the peak of the BCG signal. Note that the process for calculating the BCG signal described here is just one example, and the specific content of the process is not limited as long as it calculates a BCG signal from body movement data. For example, the type of filter is not limited as long as it can remove noise.

[0027] Next, the calculation unit 35 calculates the reliability of the BCG signal calculated in step S13 (S14). Figure 5 is a flowchart of the method for calculating the reliability.

[0028] The calculation unit 35, for example, detects peaks in the BCG signal (S14a) and calculates the time interval T (see Figure 4) between adjacent peaks in a certain section of the BCG signal (S14b). If there are n peaks (where n is a natural number) in a certain section, the calculation unit 35 can calculate n-1 time intervals. This time interval between peaks can be said to be a parameter equivalent to the RR interval in an ECG (Electrocardiogram) signal.

[0029] Next, the calculation unit 35 calculates the average value of n-1 time intervals (S14c) and identifies the number of time intervals k (where k is a natural number) that fall within a predetermined range centered on the average value (for example, average value ± average value × 20%) (S14d). The number k represents the number of time intervals that are considered normal. The calculation unit 35 calculates (k / n-1) × 100 [%] as the confidence level (S14e).

[0030] The process for calculating reliability described here is just one example; any process that calculates parameters reflecting the reliability of the BCG signal is acceptable, and the method for calculating reliability is not particularly limited.

[0031] Next, the calculation unit 35 determines the signal strength of the BCG signal calculated in step S13 (S15). Figure 6 is a flowchart of the signal strength determination method.

[0032] The calculation unit 35, for example, detects the peak of the BCG signal (S15a) and calculates the average value of the detected peak signal level (hereinafter also simply referred to as the peak level) over a certain interval of the BCG signal (S15b).

[0033] The calculation unit 35 determines whether the average value of the peak levels calculated in step S15b is greater than the first threshold and less than the second threshold (>first threshold) (S15c). If the average value of the peak levels is greater than the first threshold and less than the second threshold (Yes in S15c), the calculation unit 35 determines that the signal intensity is normal (S15d).

[0034] On the other hand, the calculation unit 35 determines that the signal strength is weak (S15e) if the average value of the peak levels is below the first threshold (below the first threshold in S15c), and determines that the user is not stationary (there is movement) relative to the motion sensor 20 (S15f) if the average value of the peak levels is above the second threshold (above the second threshold in S15c). The first and second thresholds may be determined empirically or experimentally as appropriate. The signal strength determination method described here is just one example. The signal strength may be determined based on the difference between the maximum and minimum values ​​within a single pulse, rather than the peak level. The signal strength determination method is not particularly limited.

[0035] Next, the display control unit 37 displays a support image on the display device 50 (S16) that includes the waveform of the BCG signal calculated in step S13, the reliability calculated in step S14, and the signal strength determination result in step S15. The display control unit 37 displays the support image on the display device 50 by, for example, transmitting information for displaying the support image to the display device 50 using the communication unit 31. Figure 7 shows an example of a support image.

[0036] As shown in Figure 7, the display control unit 37 displays the BCG signal waveform (corresponding to the waveform currently being measured in Figure 7), reliability, and signal strength determination result on the display device 50 as a support image. Regarding signal strength, one of the following will be displayed based on the flowchart in Figure 6: "Normal," "Weak Signal," or "Body Movement Present," but a numerical value for signal strength may also be displayed.

[0037] The waveform, reliability, and signal strength determination results of the BCG signal are updated periodically. In other words, the waveform, reliability, and signal strength determination results of the BCG signal are displayed in real time. Here, "real time" does not mean strictly real time, but rather that it is practically real time. "Displayed in real time" may mean that the BCG signal etc. may be displayed after a delay time has elapsed due to signal processing etc. after the body motion data is measured by the body motion sensor 20.

[0038] Furthermore, as shown in Figure 7, when the display control unit 37 displays the waveform of the BCG signal on the display device 50 in real time, it displays on the display device 50 an example of the BCG signal waveform when the body motion data is measured correctly (hereinafter also simply referred to as the OK example) and an example of the BCG signal waveform when the body motion data is not measured correctly (hereinafter also simply referred to as the NG example). In other words, the display control unit 37 simultaneously displays the waveform of the BCG signal currently being measured, the OK example, and the NG example on the display device 50. The OK example and the NG example are pre-prepared still images, which are stored, for example, in the storage unit 33.

[0039] With such supportive images, even users without knowledge of the body motion sensor 20 and BCG signals can adjust their body position or orientation relative to the body motion sensor 20 while viewing the display device 50 so that the waveform of their BCG signal, displayed in real time, becomes similar to the waveform in the OK example. Alternatively, the user can adjust the position or orientation of the body motion sensor 20 while viewing the display device 50. In other words, the control device 30 can assist the user in adjusting the position or orientation of their body or the body motion sensor 20 so that body motion data is measured appropriately.

[0040] In this support operation, the BCG signal was displayed in the support image, but the processing in step S13 may be omitted, and the support image may display body movement data (original data transmitted by the body movement sensor 20) in real time. In this case, the display device 50 will display the user's current body movement data in real time, and will also display examples of OK body movement data and NG body movement data. Thus, the display device 50 only needs to display the waveform of the heart rate-related signal obtained from the body movement data (i.e., the waveform of the body movement data itself that includes components derived from the heart rate, or the waveform of the signal obtained by processing the body movement data, such as the BCG signal).

[0041] Furthermore, it is not mandatory for the reliability and signal strength determination results to be displayed in the support image, and the processing in steps S14 and S15 may be omitted.

[0042] [Differentiation] In the above embodiment, support operations were described for assisting the appropriate measurement of body movement data for users taking a nap in the nap booth 10. However, these support operations are not limited to the nap booth 10 and may also be used during normal nighttime sleep. Furthermore, these support operations may also be used, for example, by installing a body movement sensor 20 on a chair or other surface in an office, allowing the user to monitor their own physical state.

[0043] When assistive movements are used in an office setting, the user's mood or state of alertness can be estimated based on the body movement data appropriately measured by the assistive movements. Based on this estimation, the user's surrounding environment (such as brightness, temperature, scent, or airflow) may be adjusted to promote alertness or calmness. This can improve work efficiency and reduce the accumulation of fatigue.

[0044] Furthermore, the methods (means) for adjusting the user's surrounding environment are not limited to the items listed above, and other methods that improve work efficiency or reduce fatigue may be employed. Also, while the effects of improving sleep onset in the nap booth 10, improving efficiency in the office, and reducing fatigue were explained here as examples, the application is not limited to any other use that has a similar effect.

[0045] [Other variations] In the above embodiment, body movement data was used to measure sleep depth. However, the use of body movement data is not particularly limited. For example, body movement data may be used to estimate changes in the user's state before and after napping.

[0046] Furthermore, it is not essential that the support images be displayed on the display device 50 installed in the nap booth 10. For example, the method of displaying support images described in the above embodiment may be applied to a display device installed in a nap room (a room originally installed in the building) located within a building such as an office building.

[0047] Furthermore, the method of displaying support images may be used to improve the accuracy of motion data measurement and may be used for purposes unrelated to sleep. When the method of displaying support images is used for purposes unrelated to sleep, the motion sensor 20 may be placed on the backrest, seat, or surrounding area of ​​a chair instead of the bed.

[0048] [Effects, etc.] The inventions derived from the disclosures in this specification include, for example, the following. The inventions derived from the disclosures in this specification will be described below, along with the effects obtained by such inventions.

[0049] Invention 1 comprises an acquisition unit 34 that acquires user body movement data measured by a body movement sensor 20, and a display control unit 37 that displays the waveform of a heart rate-related signal obtained from the acquired body movement data on a display device 50 in real time. The display control unit 37 is a display control device that, when the waveform of a heart rate-related signal is displayed on the display device 50 in real time, displays on the display device 50 an example of a heart rate-related signal waveform obtained when the body movement data is measured correctly, and an example of a heart rate-related signal waveform obtained when the body movement data is not measured correctly. The display control device corresponds to the control device 30 in the above embodiment.

[0050] Such a display control device can help the user adjust the position or orientation of their body or sensor so that body movement data is measured appropriately by simultaneously displaying OK examples and NG examples when the waveform of the heart rate-related signal is displayed in real time on the display device 50.

[0051] Invention 2 is a display control device of Invention 1, further comprising a calculation unit 35 that calculates a BCG signal from body movement data, and a display control unit 37 that displays the calculated BCG signal waveform on a display device 50 in real time as a waveform of a signal related to heart rate, and when the calculated BCG signal waveform is displayed on the display device 50 in real time, displays on the display device 50 an example of the BCG signal waveform when the body movement data is measured correctly and an example of the BCG signal waveform when the body movement data is not measured correctly.

[0052] Such a display control device can help the user adjust the position or orientation of their body or sensor so that body movement data is measured appropriately by simultaneously displaying OK examples and NG examples when the waveform of the BCG signal is displayed in real time on the display device 50.

[0053] Invention 3 is a display control device of Invention 2, wherein the calculation unit 35 further calculates the reliability of the calculated BCG signal based on the time interval of the peaks in the calculated BCG signal, and the display control unit 37 displays the calculated reliability on the display device 50 when the waveform of the calculated BCG signal is displayed on the display device 50 in real time.

[0054] Such a display control device can help the user adjust the position or orientation of their body or sensor so that motion data is measured appropriately by simultaneously displaying the reliability level when the waveform of the BCG signal is displayed in real time on the display device 50.

[0055] Invention 4 is a display control device of Invention 2 or 3, wherein the calculation unit 35 further determines the signal strength of the calculated BCG signal based on the peak signal level of the calculated BCG signal, and the display control unit 37 displays the result of the determination of the calculated signal strength on the display device 50 when the waveform of the calculated BCG signal is displayed on the display device 50 in real time.

[0056] Such a display control device can help the user adjust the position or orientation of their body or sensor so that body movement data is measured appropriately by simultaneously displaying the signal strength determination result when the waveform of the BCG signal is displayed in real time on the display device 50.

[0057] Invention 5 is a private booth comprising a display control device from any of Inventions 1 to 4, a body motion sensor 20, a bed on which the body motion sensor 20 is provided, and a display device 50. The private booth corresponds to the nap booth 10 in the above embodiment.

[0058] Such private booths can help users lying on a bed in the booth adjust the position or orientation of their body or sensors so that body movement data is properly measured, by simultaneously displaying OK examples and NG examples when the waveform of the heart rate-related signal is displayed in real time on the display device 50.

[0059] Invention 6 is a private booth comprising a display control device from any of Inventions 1 to 4, a body motion sensor 20, a chair on which the body motion sensor 20 is provided, and a display device 50.

[0060] Such private booths can help users sitting in a chair within the booth adjust the position or orientation of their body or sensors so that body movement data is properly measured, by simultaneously displaying both OK and NG examples when the waveform of the heart rate-related signal is displayed in real time on the display device 50.

[0061] Invention 7 is a display method performed by a computer, comprising an acquisition step S12 for acquiring user body movement data measured by a body movement sensor 20, and a display step S16 for displaying the waveform of a heart rate-related signal obtained from the acquired body movement data on a display device 50 in real time, wherein in the display step S16, when the waveform of the heart rate-related signal is displayed on the display device 50 in real time, an example of the waveform of the heart rate-related signal obtained when the body movement data is measured correctly and an example of the waveform of the heart rate-related signal obtained when the body movement data is not measured correctly are displayed on the display device 50.

[0062] This display method, by simultaneously displaying both OK and NG examples while the waveform of the heart rate-related signal is displayed in real time on the display device 50, can help the user adjust the position or orientation of their body or sensor so that body movement data is measured appropriately.

[0063] Invention 8 is a program for causing a computer to execute the display method of Invention 7.

[0064] According to such a program, the computer can help the user adjust the position or orientation of their body or sensors so that body movement data is measured properly by simultaneously displaying OK examples and NG examples when the waveform of the heart rate-related signal is displayed in real time on the display device 50.

[0065] (Other embodiments) Although the nap booth according to the embodiment has been described above, the present invention is not limited to the above embodiment.

[0066] For example, in the above embodiment, a process performed by a specific processing unit may be performed by another processing unit. Furthermore, the order of multiple processes may be changed, or multiple processes may be executed in parallel.

[0067] Furthermore, in the above embodiment, each component may be realized by executing a software program suitable for each component. Each component may also be realized by a program execution unit such as a CPU or processor reading and executing a software program recorded on a recording medium such as a hard disk or semiconductor memory.

[0068] Furthermore, each component may be implemented by hardware. For example, each component may be a circuit (or integrated circuit). These circuits may form a single circuit as a whole, or they may be separate circuits. Also, each of these circuits may be a general-purpose circuit or a dedicated circuit.

[0069] Furthermore, general or specific embodiments of the present invention may be implemented as a system, apparatus, method, integrated circuit, computer program, or recording medium such as a computer-readable CD-ROM. They may also be implemented in any combination of a system, apparatus, method, integrated circuit, computer program, and recording medium. For example, the present invention may be implemented as a display system, or as a display method executed by a computer such as a display control device. Alternatively, the present invention may be implemented as a program for causing a computer to execute a display method, or as a computer-readable non-temporary recording medium on which such a program is stored.

[0070] Furthermore, the present invention also includes forms obtained by applying various modifications to each embodiment that a person skilled in the art could conceive, or forms realized by arbitrarily combining the components and functions of each embodiment without departing from the spirit of the present invention. [Explanation of Symbols]

[0071] 10 Nap Booths 20 Motion sensors 30 Control device 31 Communications Department 32 Information Processing Section 33 Storage section 34 Acquisition Department 35 Calculation Section 36 Equipment Control Unit 37 Display Control Unit 40 Environmental control equipment 50 Display device

Claims

1. An acquisition unit that acquires user body movement data measured by sensors, The system includes a display control unit that displays the waveform of a heart rate-related signal obtained from the acquired body movement data on a display device in real time, When the waveform of the heart rate-related signal is displayed on the display device in real time, the display control unit displays on the display device an example of the heart rate-related signal waveform obtained when the body movement data is measured correctly, and an example of the heart rate-related signal waveform obtained when the body movement data is not measured correctly. Display control device.

2. Furthermore, it includes a calculation unit that calculates a BCG (Ballistocardogram) signal from the aforementioned body motion data. The display control unit, The waveform of the BCG signal calculated as the waveform of the heart rate is displayed in real time on the display device. When the calculated BCG signal waveform is displayed on the display device in real time, the display device will show an example of the BCG signal waveform when the body movement data is measured correctly, and an example of the BCG signal waveform when the body movement data is not measured correctly. The display control device according to claim 1.

3. The calculation unit further calculates the reliability of the calculated BCG signal based on the time interval of the peaks in the calculated BCG signal. The display control unit displays the calculated reliability on the display device when the calculated BCG signal waveform is displayed on the display device in real time. The display control device according to claim 2.

4. The calculation unit further determines the signal intensity of the calculated BCG signal based on the peak signal level of the calculated BCG signal. The display control unit displays the calculated signal strength determination result on the display device when the calculated BCG signal waveform is displayed on the display device in real time. The display control device according to claim 2.

5. A display control device according to any one of claims 1 to 4, The aforementioned sensor and, A bed on which the aforementioned sensor is provided, The device comprises the aforementioned display device. Private booth.

6. A display control device according to any one of claims 1 to 4, The aforementioned sensor and, A chair on which the aforementioned sensor is provided, The device comprises the aforementioned display device. Private booth.

7. A display method performed by a computer, An acquisition step to acquire user body movement data measured by a sensor, The process includes a display step of displaying the waveform of a heart rate-related signal obtained from the acquired body movement data on a display device in real time, In the display step, when the waveform of the heart rate-related signal is displayed on the display device in real time, an example of the heart rate-related signal waveform obtained when the body movement data is measured correctly and an example of the heart rate-related signal waveform obtained when the body movement data is not measured correctly are displayed on the display device. Display method.

8. A program for causing the computer to execute the display method described in claim 7.

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