Seating action determination system and attitude change detection system

Abstract

To provide a seating action determination system capable of being simply applied to an existing chair and capable of ordinarily evaluating a seating action.SOLUTION: A seating action determination system comprises: a ranging part for measuring a distance between a chair and a seated person; an impact detection part for measuring magnitude of an impact during seating; and a determination part for determining whether or not he / she can gently sit on the chair. Thus, since the seating action determination system can be simply applied to the existing chair and can ordinarily evaluate a seating action, it can early grasp a change in motor function and can be used to maintain or improve rehabilitation and activities of daily living.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a sitting motion determination system for use in rehabilitation and maintaining or improving activities of daily living. [Background technology]

[0002] Activities of daily living are important for people to live independently, and assessment of motor function to maintain or improve these activities is carried out in medical and nursing care settings. Conventionally, a motor function assessment method using a chair has been proposed, such as that disclosed in Patent Document 1. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-92977 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the motor function evaluation method disclosed in Patent Document 1 is specialized for use in evaluating standing-up movements, and does not describe specific embodiments for evaluating sitting-down movements. Sitting-down movements, like standing-up movements, are frequently performed in daily life, but are not considered problematic if the sitting position is stable after sitting down. Therefore, a simple evaluation method that can quickly identify changes in motor function related to sitting is desired. Furthermore, the motor function evaluation method disclosed in Patent Document 1 requires a measuring unit with a built-in load sensor to be placed on the seat or under the feet of a chair, and is not intended to be permanently installed on chairs used daily. Therefore, an object of the present invention is to provide a sitting motion determination system that can be easily applied to existing chairs and that can evaluate sitting motions on a daily basis. [Means for solving the problem]

[0005] The present invention provides a sitting action determination system that determines whether the sitting action on a chair is correct or not. The above-mentioned seating motion judgment system comprises a distance measurement unit, an impact detection unit, and a judgment unit, wherein the distance measurement unit measures the distance between the chair and the occupant, the impact detection unit measures the magnitude of the impact when sitting down, and the judgment unit judges whether the occupant was able to sit down quietly on the chair. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide a sitting movement determination system that can be easily applied to existing chairs and that can evaluate sitting movements on a daily basis. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a schematic diagram of a seating movement determination system according to the present invention; [Figure 2] 1 is a diagram of a chair equipped with a sitting motion determination system of the present invention. [Figure 3] FIG. 1 is a flow chart of an embodiment of a seating movement determination system according to the present invention. [Figure 4] FIG. 1 is a flow chart of an embodiment of a seating movement determination system according to the present invention. [Figure 5] FIG. 10 is a diagram showing a configuration in which a plurality of seating movement determination devices are connected to a monitor device via a network. [Figure 6] FIG. 1 is a flow chart of an embodiment of a posture change detection system of the present invention. [Figure 7] FIG. 10 is a diagram showing an example of a screen display on a monitor device. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0009] 1 is a schematic diagram of a seating movement determination system 10 of the present invention. A determination unit 13 obtains distance from a distance measurement unit 11 and acceleration from an impact detection unit 12, processes the data, and outputs the determination result to a notification unit 14.

[0010] FIG. 2 is a schematic diagram of a seating movement determination device 1 according to one embodiment of the present invention and a chair 2 equipped with the seating movement determination device 1. The seating movement determination device 1 includes a microcomputer 1a incorporating an impact detection unit 12 and a determination unit 13, a distance measurement unit 1b incorporating a distance measurement unit 11, and a cable 1c connecting the microcomputer 1a and the distance measurement unit 1b. The impact detection unit 12 includes an acceleration sensor for detecting an impact. The acceleration sensor may be, for example, a piezoelectric, piezo-resistive, frequency change, or capacitance type. Alternatively, an inertial sensor such as an IMU (inertial measurement unit) may be used. The distance measurement unit 11 includes a distance sensor for detecting the approach of a seated person. The distance sensor may be, for example, a time-of-flight (ToF) type using laser light or ultrasonic waves. Alternatively, a capacitance type proximity sensor or an infrared human sensor may be used. The microcomputer 1a includes a notification unit 14 to which the determination result is output. The notification unit 14 may display or output audio using a display or speaker, or may notify an external terminal using a wireless communication function. The microcomputer 1a may be equipped with a battery as a power source for the seating behavior determination device 1. The microcomputer 1a is fixed to a position where it can detect an impact when sitting, such as the back of the chair 2. The fixing method is not important, so a new mechanism for attachment may be provided. The distance measurement unit 1b is installed in a direction where it can detect the occupant's seating. In FIG. 2, it is installed facing forward from a gap on the left side of the back of the chair 2, but it may also be installed in the center of the back or on the seat as long as it does not interfere with sitting.

[0011] FIG. 3 is a flow diagram in which the determining unit 13 uses only the distance measuring unit 11 to determine whether or not a person has sat down, and details thereof will be described in the first embodiment.

[0012] FIG. 4 is a flow diagram in which the determining unit 13 uses the distance measuring unit 11 and the impact detecting unit 12 to determine whether or not a person has been seated, and details thereof will be described in the second embodiment. [Example]

[0013] 3 is a flow chart showing the flow of the seating movement determination process realized by the seating movement determination system of the present invention. By repeating the process shown in the flow chart, it is possible to perform a determination every time a seating movement occurs. Furthermore, for purposes such as rehabilitation, the number of times that seating movement is determined may be set.

[0014] First, the distance measurement unit 11 acquires the distance between the chair 2 and the seated person (S11).

[0015] Next, the determination unit 13 determines that the person is seated if the acquired distance is smaller than the threshold value, and determines that the person is not seated if the acquired distance is smaller than the threshold value (S12). If it is determined that the person is not seated, the determination unit 13 acquires the distance again and determines whether the person is seated.

[0016] If it is determined that the person has sat down, the acceleration is acquired from the impact detection unit 12 (S13).

[0017] Finally, if the acquired acceleration is greater than the threshold value, the determination unit 13 determines that the subject was unable to sit quietly, otherwise it determines that the subject was able to sit quietly (S14). If it is determined that the subject was unable to sit quietly, it notifies the subject that the subject was unable to sit quietly (S15a). If it is determined that the subject was able to sit quietly, it notifies the subject that the subject was able to sit quietly (S15b). The notification is made by the notification unit 14. The notification method may be audio output from a speaker built into the microcomputer 1a, display on a display, or output of the result to an external terminal via a wireless communication function. [Example]

[0018] It is possible to determine and notify seated behavior using the method of Example 1. Furthermore, a flow diagram showing the method for detecting seated behavior more accurately and preventing false detection when the person is not seated is shown in Figure 4.

[0019] First, the determination unit 13 stores each threshold value for determining a seating movement in advance (S101). As an example, the seating distance is 100 mm, the movement acceleration is 0.20 G, the seating acceleration is 0.05 G, and the movement distance is 250 mm. The role of each threshold value is as follows:

[0020] The seating distance is a threshold for determining that an occupant is seated if they approach, and not seated if they move away. Distance measurement unit 1b, installed facing forward from the back of the chair, measures the distance to the occupant, and determination unit 13 compares that distance with the threshold, determining that an occupant is seated if they are closer than 100 mm from the back of the chair. Conversely, if the occupant is more than 100 mm from the back of the chair, it is determined that they are not seated.

[0021] The motion acceleration is a threshold for determining whether a person sat quietly if the impact when sitting down was small, or whether a person sat quietly if the impact was large. A microcomputer 1a installed on the back of the chair measures the acceleration when sitting down, and a determination unit 13 compares the acceleration (degree of impact) with a threshold, determining that a person did not sit quietly if the acceleration when sitting down was greater than 0.20 G. Conversely, if the acceleration when sitting down was 0.20 G or less, it determines that a person sat quietly.

[0022] Other thresholds (seating acceleration, movement distance) are not set in Example 1, but are set in Example 2 to improve the accuracy of the determination. This allows for more accurate determination of, for example, when a person sits down forcefully on a chair or when they sit down shallowly. It also makes it possible to reduce false detections when the person is not seated.

[0023] These threshold values are set according to the shape and material of the chair 2 equipped with the sitting action determination system so that the sitting action determination can be performed correctly.

[0024] Next, the determination unit 13 acquires the distance from the distance measurement unit 11 (S111). The determination unit 13 also acquires the acceleration from the impact detection unit 12 (S112).

[0025] From the values obtained up to this point, the determination unit 13 determines that the person is seated if the acquired distance is smaller than the seating distance or the acquired acceleration is greater than the seating acceleration (S121). If it is determined that the person is not seated, the processes of S111 and S112 are repeated until the person is seated. If it is determined that the person is seated, the process proceeds to the next step.

[0026] The acceleration is continuously acquired for a certain period of time from the time of seating, and the maximum value is acquired and set as the maximum acceleration (S131). In this embodiment, the maximum acceleration value for one second is acquired in order to output the determination result one second after the time of seating determination. In addition, the distance is acquired from the distance measurement unit 11 (S132).

[0027] Here, before determining whether the person has sat down, it is determined again whether the person has sat down (S133). This process takes into consideration that a certain time (1 second in this embodiment) has passed since the person sat down, and this prevents erroneous operation when the person is not seated, such as when the chair 2 is moved by being picked up.

[0028] Finally, if the maximum acceleration is greater than the motion acceleration, it is determined that the person did not sit quietly; otherwise, it is determined that the person sat quietly (S141). If it is determined that the person did not sit quietly, it is notified that the person did not sit well (S151a). If it is determined that the person sat quietly, it is notified that the person sat well (S151b).

[0029] As described above, the present invention determines sitting behavior without using a load sensor, so it can be retrofitted to an existing chair without interfering with seat maintenance, making it particularly suitable for use in nursing care facilities, etc. Furthermore, since it is suitable for permanent installation, it is possible to run a sitting behavior improvement program using the present invention at any time. [Example]

[0030] In nursing care facilities and the like, there is a task of encouraging users to change their posture in order to prevent the user from being pressed down on a chair for a long period of time. Therefore, it is desirable to be able to check the usage status of a chair 2 equipped with a seating movement determination device 1 and the posture change of the seated user from a remote location such as a staff room. Therefore, in this embodiment, a posture change detection system 20 is proposed that uses a seating movement determination device 1 equipped with a wireless communication function.

[0031] FIG. 5 is a diagram showing that a plurality of seating movement determination devices 1 are connected to a monitor device 3 via a network 5. The posture change detection system 20 detects whether or not the person is seated using a distance measurement unit, and detects the movement while seated using an impact detection unit. Therefore, the posture change detection system 20 can be operated on the seating movement determination device 1, similar to the seating movement determination system 10. Furthermore, the posture change detection system 20 can determine the seating situation, such as whether or not the person is seated and whether or not there is a change in posture, using a determination unit, and can notify the seating situation to the outside using a notification unit.

[0032] Since the chair 2 equipped with the seating motion determination device 1 may be moved by the seated person or the like, it is desirable that communication between the seating motion determination device 1 and the network 5 be performed wirelessly. On the other hand, since the monitor device 3 is expected to be installed in a fixed location such as a staff room, communication with the network 5 does not necessarily have to be wireless. Therefore, the communication standard between the seating motion determination device 1 and the network 5 may be different from the communication standard between the monitor device 3 and the network 5. Furthermore, the network 5 may be equipped with a gateway for converting between different communication standards, and may be able to manage terminals via an external service such as the cloud.

[0033] Figure 6 is a flow diagram of an embodiment of the posture change detection system of the present invention. By repeating the process shown in the flow diagram, it is possible to make a determination at any time while sitting. Since posture change detection system 20 has the same configuration as seating movement determination system 10, from this paragraph onwards, Figure 1 will be used as a schematic diagram of posture change detection system 20.

[0034] First, a count for measuring the time when there is no movement is reset (S21). As an example, a process is performed to reset the count, which continues to increase while there is no movement, to 0.

[0035] Next, the distance measurement unit 11 acquires the distance between the chair 2 and the seated person (S22). If the acquired distance is smaller than the threshold, the determination unit 13 determines that the person is seated, otherwise determines that the person is not seated (S23). If it is determined that the person is not seated, the count is reset again and it is determined whether or not the person is seated.

[0036] If it is determined that the person is seated, the acceleration is acquired from the impact detection unit 12 (S24), and if the acquired acceleration is greater than a threshold value, the determination unit 13 determines that there is movement, otherwise it determines that there is no movement (S25). If it is determined that there is movement, the count is reset again, and it is determined whether the person is seated and whether there is movement. If it is determined that there is no movement, the count is incremented by 1 (S26).

[0037] Finally, it is determined whether the count is equal to or greater than a set value (S27), and if so, a notification is issued that there has been no movement for a certain period of time (S28). If not, it is determined again whether the person is seated, whether there is movement, and whether the count is equal to or greater than a set value. This allows a notification to be issued if there has been no movement for a certain period of time while seated.

[0038] The notification is made by the notification unit 14. The notification content includes the seating status, such as whether the person is seated or not, whether there is a change in posture, etc. In addition, a number for identifying the seated person, remaining battery level, and other information may be added.

[0039] The monitor device 3, which receives notifications from the seating movement determination device 1 equipped with the posture change detection system 20, may receive notifications from multiple seating movement determination devices 1 and display them on the same screen. FIG. 7 is a diagram showing an example of a screen display on the monitor device 3. The seating status of 10 chairs is shown with an icon, which is suitable for management work in group homes, etc. The posture change status may be displayed as letters or numbers, or may be represented by the icon or its background color. Also, a sound may be emitted if there is no movement for a certain period of time.

[0040] As described above, the present invention can realize both seating movement determination and posture change detection using the same hardware. Note that the posture change detection system 20 may be operated in parallel with the seating movement determination system 10. [Explanation of symbols]

[0041] 1. Seating behavior determination device 1a microcontroller 1b Distance measuring unit 1c cable 2 chairs 3. Monitor device 5. Network 10. Seating behavior determination system 20 Posture change detection system

Claims

1. This is a sitting action determination system for determining whether the action of sitting on a chair is good or bad, and is equipped with a distance measuring unit for measuring the distance between the chair and the occupant, an impact detecting unit for measuring the magnitude of the impact when sitting, and a determining unit for determining whether the occupant has been able to sit on the chair quietly.

2. A chair equipped with the sitting action determination system according to claim 1.

3. This posture change detection system detects a state in which a person has been sitting on a chair without moving for a certain period of time, and includes a distance measuring unit that measures the distance between the chair and the person sitting on it, an impact detecting unit that measures the magnitude of the person's movements while sitting on it, and a determining unit that determines whether or not there has been any movement for a certain period of time after sitting on the chair.

4. A chair equipped with the posture change detection system according to claim 3.

5. A chair comprising: the posture change detection system according to claim 1; and the sitting action determination system according to claim 3.

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