Motion discrimination system

Abstract

To provide a motion discrimination device capable of detecting a state that a user raises his or her upper body on a bed.SOLUTION: A motion discrimination system 10 includes a bed 20 and a motion discrimination device 11 for discriminating a motion of a user U on the bed 20. The motion discrimination device 11 includes a sensor 30 for detecting a change in a load that the user U applies and a discrimination device 42 for receiving an output signal output by the sensor 30 and discriminating the motion of the user U. The bed 20 includes a bed body 20a and a mattress 25 placed on the bed body 20a. The sensor 30 formed in a belt-like shape is arranged between the bed body 20a and the mattress 25, and arranged at a position corresponding to the body of the user U in an on-bed state in which the user U lies on the mattress 25. The discrimination device 42 discriminates a raised state in which the user U raises his or her upper body on the bed 20 on the basis of the output signal.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a motion detection system. [Background technology]

[0002] Conventionally, in hospitals, nursing homes, etc., when a care recipient, such as a physically disabled patient or elderly person, who is in bed and tries to get out of bed on his or her own, there is a risk of falling or tripping over. Therefore, a bed exit sensor that detects when the care recipient leaves the bed and notifies the caregiver when the bed exit sensor detects that the care recipient has left the bed has been considered to assist the care recipient in getting out of bed.

[0003] Japanese Patent Publication No. 2012-29871 (Patent Document 1) discloses a bed exit sensor such as the one described above, in which a pressure sensor is placed on the bed and determines that the user has exited bed when the user's body pressure detected by the pressure sensor falls below a predetermined value.

[0004] In addition, Japanese Patent Application Laid-Open Publication No. 2012-11174 (Patent Document 2) proposes a bed exit sensor that is provided with a load sensor on each leg of the bed and determines that the patient has exited the bed when the amount of movement of the load center of gravity detected by the load sensors falls below a predetermined value. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-29871 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-11174 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the bed exit sensors described in Patent Documents 1 and 2 detect the user's exit from the bed after the user has completely exited the bed. For this reason, it is preferable to detect the user's movement at an earlier stage than when the user exits the bed.

[0007] The present invention has been made in view of the above background, and aims to provide a movement determination system that detects when a user sits up in bed. [Means for solving the problem]

[0008] One aspect of the present invention is A motion determination system including a bed and a motion determination device that determines the motion of a user on the bed, The movement determination device includes: a sensor that detects a change in the load applied by the user; a determination device that receives an output signal from the sensor and determines the user's action, The bed is The bed itself, and a mattress placed on the bed body, The sensor The support member is formed in a belt shape, and is disposed between the bed body and the bedding, and is disposed at a position corresponding to the torso of the user when the user is lying on the bedding, The discrimination device is a motion discrimination system that discriminates, based on the output signal, whether the user has raised his / her upper body on the bed or not. [Effects of the Invention]

[0009] According to one aspect of the present invention, it is possible to detect a state in which the user has raised his / her upper body on the bed before it is determined that the user is in a state of getting out of bed. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a block diagram showing a motion determination system according to a first embodiment. [Figure 2] 2 is a cross-sectional view of the bed according to the first embodiment taken along line II-II in FIG. 1. FIG. [Figure 3] 1 is a plan view showing the bed according to the first embodiment with the mattress removed. FIG. [Figure 4] 1 is a cross-sectional view showing a sensor according to a first embodiment. [Figure 5] 1A and 1B are diagrams showing signals generated by the movement discrimination device according to the first embodiment, where (a) is an output signal, (b) is a heartbeat frequency signal, and (c) is a respiratory frequency signal. [Figure 6] FIG. 1 is a diagram for explaining a bed-sitting state (resting state) in the first embodiment. [Figure 7] FIG. 1 is a diagram for explaining an in-bed state (active state) in the first embodiment. [Figure 8] FIG. 10 is a diagram for explaining a standing state in the first embodiment. [Figure 9] FIG. 10 is a diagram for explaining an end-seated state in the first embodiment. [Figure 10] FIG. 10 is a diagram for explaining the bed exit state in the first embodiment. [Figure 11] 10 is a flowchart showing a process for determining a standing-up state in the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] (Embodiment 1) 1. Overview of the motion detection system An embodiment in which the present invention is applied to a motion detection system will be described below. The motion detection system according to this embodiment detects the motion of a bed user. The bed user can be in various states, such as a bed-in-bed state in which the user lies quietly on the bed, an active state in which the user turns over in bed, a sitting-up state in which the user sits up on the bed, and an out-of-bed state in which the user leaves the bed.

[0012] If a user is physically disabled or elderly, there is a risk that the user may fall or trip from the bed when trying to leave the bed. Therefore, it is desirable to detect the user's attempt to leave the bed as early as possible. The movement determination device according to this embodiment can determine the movement of the user sitting up on the bed when starting to leave the bed.

[0013] 2. Configuration of the movement determination system 10 The movement determination system 10 of this embodiment will be described below with reference to Figs. 1 to 4. The movement determination system 10 of this embodiment includes a movement determination device 11 and a bed 20. The bed 20 is formed into a shape that is long overall in the head-to-foot direction. The head-to-foot direction is defined as a direction including the head and feet of a user U. The bed 20 includes a bed body 20a, a mattress 25 (an example of bedding), and handrails 26. In the following description, when multiple identical components are used, only some of the components will be assigned reference numerals, and the reference numerals may be omitted for other components.

[0014] As shown in FIGS. 1 and 2 , the bed 20 includes a bed body 20a, a mattress 25, and a handrail 26. The bed body 20a includes a headboard 21, a footboard 22, a frame 23, and a floorboard 24. The bed body 20a includes the headboard 21 extending vertically on the head side in the head-to-foot direction, and the footboard 22 extending vertically on the foot side in the head-to-foot direction. The materials for the headboard 21 and the footboard 22 are not particularly limited and may be wood or metal. The headboard 21 and the footboard 22 are connected by a pair of frames 23 that are elongated in the head-to-foot direction. The frames 23 are disposed at both left and right ends of the bed 20. The material for the frames 23 is not particularly limited, but metal is preferable to support the weight of the user U. However, the bed 20 may also be configured with a frame-shaped frame and legs extending downward from the four corners of the frame.

[0015] As shown in FIG. 3, a plurality of (seven in this embodiment) floorboards 24 extending in the left-right direction are arranged between a pair of frames 23 so as to span the pair of frames 23. There are no particular limitations on the material from which the floorboards 24 are made, and any material such as wood, resin, or metal can be selected. There are no particular limitations on the number of floorboards 24, and the number may be one, or two to six, or eight or more. Adjacent floorboards 24 are arranged with a gap between them. However, adjacent floorboards 24 may also be arranged so as to be in contact with each other.

[0016] As shown in Fig. 2, a mattress 25 is placed on the floorboard 24. However, other examples of bedding such as a futon or a blanket may be placed on the floorboard 24. The mattress 25 is formed in a rectangular shape that is long in the head-to-foot direction when viewed from above. The mattress 25 is arranged so as to cover the floorboard 24 in the vertical direction. However, a user U is omitted from Fig. 2.

[0017] As shown in FIG. 1 , handrails 26 are provided on at least both sides (both left and right sides) of the bed 20 where the torso of the user U is located. The handrails 26 may be provided on only one side in the left-right direction. The torso refers to the body of the user U excluding the head, neck, and limbs. The handrails 26 are provided to protrude above the upper surface of the mattress 25. The handrails 26 are provided on the head side of the bed 20 in the head-to-foot direction, but not on the foot side. The handrails 26 are provided to support the upper body of the user U when he or she stands up from the bed 20 and to prevent the user U from falling from the bed 20. The material of the handrails 26 is not particularly limited and can be selected appropriately from wood, resin, metal, etc. The handrails 26 in this embodiment are made of metal.

[0018] Because the handrail 26 is provided, when the user U gets off the bed 20, he or she gets off from an area of the bed 20 where the handrail 26 is not located. In this way, in this embodiment, the bed exit area where the user U can get off the bed 20 is set to the foot side in the head-to-foot direction, i.e., the area where the handrail 26 is not located. This allows the user U to get off the bed 20 only from the foot side in the head-to-foot direction. As a result, the range of movement of the user U is restricted, and the accuracy of detecting the movement of the user U can be improved.

[0019] As shown in FIG. 1 , the sensor 30 is disposed on the bed 20 in an area where movement in the left-right direction is restricted by the handrail 26. More specifically, the sensor 30 is disposed on the bed 20 at a position corresponding to the torso of the user U when the user U is lying on the bed 20. The sensor 30 is preferably disposed at a position corresponding to the area between the shoulders and waist of the user U's torso. Furthermore, disposing the sensor 30 at a position corresponding to the area between the armpits and navel of the user U's torso is more preferable because it allows for accurate detection of the user U's heart rate or breathing, and it is even more preferable to dispose the sensor at a position corresponding to the solar plexus. The length of the sensor 30 in the left-right direction is preferably set to a size that enables detection of the movement of the user U on the bed 20. The length of the sensor 30 in the left-right direction is preferably set to 80% or more of the width of the bed 20 in the left-right direction, more preferably 90% or more, and even more preferably 95% or more.

[0020] When the user U lies on the bed 20, the torso of the user U extends in the head-to-foot direction. The width dimension of the sensor 30 in the head-to-foot direction is set to be shorter than the length of the torso of the user U lying on the bed 20. Furthermore, since this reduces the manufacturing cost of the sensor 30, the width dimension of the sensor 30 in the head-to-foot direction is preferably 5 cm or more and 15 cm or less, and more preferably 9 cm or more and 11 cm or less. In this embodiment, the width dimension of the sensor 30 in the head-to-foot direction is set to be substantially 10 cm. "Substantially 10 cm" includes cases where it is 10 cm, and also includes cases where it can be recognized as being substantially 10 cm even if it is not 10 cm.

[0021] On the other hand, when the user U stands up on the bed 20 or sits on an area of the side edge of the bed 20 where no handrail is provided, the user U is not located vertically above the sensor 30. Therefore, when the user U stands up on the bed 20 or sits on an area of the side edge of the bed 20 where no handrail is provided, the sensor 30 does not directly detect pressure or vibrations caused by the heartbeat and breathing of the user U. On the other hand, the sensor 30 detects pressure or vibrations caused by the movement of the user U on the bed 20.

[0022] In this embodiment, the width dimension of the sensor 30 in the head-to-foot direction is configured so that when the user U is standing on the bed 20 or when the user U is sitting in an area of the side edge of the bed 20 where no handrail is located, the sensor 30 is not positioned vertically below the user U.

[0023] 3, the sensor 30 is disposed on the upper surface of the floorboard 24. The sensor 30 is formed in the shape of a strip that is long in the left-right direction. The length of the sensor 30 in the left-right direction is slightly shorter than the length of the floorboard 24 in the left-right direction.

[0024] The sensor 30 is placed on one of the floorboards 24 and fixed to the floorboard 24 by one or more restraining members. In this embodiment, both left and right ends of the sensor 30 are fixed to the floorboard 24 by restraining members 27. The number of restraining members 27 that fix the sensor 30 to the floorboard 24 may be three or more.

[0025] The restraining member 27 can be selected from any suitable restraining member 27 such as a belt, a hook-and-loop fastener, tape, double-sided tape, a cable tie, etc. The sensor 30 may be attached to the floor board 24 by adhesive or screws.

[0026] The sensor 30 may also be fixed to the underside of the mattress 25. There are no particular limitations on the method of fixing the sensor 30 to the mattress 25, and the sensor 30 may be glued to the underside of the mattress 25 or sewn to the underside of the mattress 25. Alternatively, a pocket capable of accommodating the sensor 30 may be formed on the underside of the mattress 25, and the sensor 30 may be accommodated in this pocket.

[0027] The sensor 30 is configured to be able to detect vibrations of the mattress 25 caused by the movements of the user U.

[0028] As shown in FIG. 4, the sensor 30 includes a substrate 31, an elastic body 32, and a sensor 30 sheet.

[0029] The base material 31 is formed long in the left-right direction. The material constituting the base material 31 is not particularly limited, and any material can be appropriately selected, such as metals such as iron, stainless steel, aluminum, and aluminum alloys, or resin. The base material 31 according to this embodiment is made of metal.

[0030] An elastic body 32 having elasticity is fixed to the upper surface of the base material 31. There are no particular limitations on the material of the elastic body 32, and any material can be appropriately selected, such as rubbers such as styrene-butadiene rubber, nitrile rubber, and butyl rubber, and foamed resins such as polyurethane foam, polystyrene foam, and polyethylene foam. There are no particular limitations on the method for fixing the base material 31 and the elastic body 32, and they may be, for example, glued or heat-sealed.

[0031] A sensor sheet 33 is fixed to the upper surface of the elastic body 32. The sensor sheet 33 is composed of a piezoelectric sensor or an electrostatic sensor. In this embodiment, the sensor sheet 33 is formed in a sheet (membrane) shape. When the sensor sheet 33 receives pressure from the underside of the mattress 25, it can output a physical quantity corresponding to the received pressure. However, the elastic body 32 and the sensor sheet 33 may not be fixed to each other, and the sensor sheet 33 may be fixed to a member different from the elastic body 32, thereby maintaining the relative positions of the elastic body 32 and the sensor sheet 33.

[0032] When the sensor sheet 33 is a piezoelectric sensor, it includes a first electrode layer 33a, a second electrode layer 33b, and an intermediate layer 33c made of a piezoelectric material, which are laminated in this order: the first electrode layer 33a, the intermediate layer 33c, and the second electrode layer 33b.

[0033] In this embodiment, the first electrode layer 33a and the second electrode layer 33b are each formed of a single conductive sheet, so that the sensor sheet 33 outputs an output signal of one channel.

[0034] Alternatively, one of the first electrode layer 33a and the second electrode layer 33b may be composed of a single conductive sheet, while the other may be composed of multiple conductive sheets arranged at a distance from each other. Furthermore, the first electrode layer 33a and the second electrode layer 33b may each be composed of multiple conductive sheets. For example, the multiple conductive sheets constituting the first electrode layer 33a and the multiple conductive sheets constituting the second electrode layer 33b may be arranged in a line or in a matrix. According to the above configuration, the sensor sheet 33 can output output signals from multiple channels. This is preferable because the multiple output signals can complement each other and the detection accuracy can be improved by considering the relationship between the multiple output signals.

[0035] When the sensor sheet 33 is a piezoelectric sensor, the intermediate layer 33c is made of a piezoelectric material. When a compressive force is applied to the intermediate layer 33c, the intermediate layer 33c generates an electric power corresponding to the compressive force. This causes the sensor sheet 33 to output an output signal corresponding to the change in the load applied to the sensor sheet 33.

[0036] The sensor sheet 33 may be configured to use an electrostatic sensor. If the sensor sheet 33 is an electrostatic sensor, it includes an intermediate layer 33c made of a dielectric material. When a compressive force is applied to the intermediate layer 33c, the distance between the first electrode layer 33a and the second electrode layer 33b is shortened, thereby changing the electrostatic capacitance between the first electrode layer 33a and the second electrode layer 33b.

[0037] 1, the sensor 30 is electrically connected to the processing device 40 by wire or wirelessly. The sensor 30 transmits an output signal to the processing device 40. The processing device 40 includes an arithmetic unit 41, a discrimination unit 42, and a storage device 43.

[0038] The computing device 41 receives the output signal transmitted from the sensor 30 and processes the output signal to generate a signal different from the output signal. The computing device 41 generates a heart rate frequency signal and a respiration frequency signal.

[0039] The output signal will be described with reference to Fig. 5. The output signal shown in Fig. 5 is a signal received by the calculation device 41 from the sensor 30. The output signal is a single-channel signal output from the sensor 30. The output signal is a signal corresponding to the amount of change in the load applied to the sensor 30. The output signal includes a signal caused by the body movement of the user U, a signal caused by the breathing of the user U, a signal caused by the heartbeat of the user U, a signal caused by the pulse of the user U, etc.

[0040] The discriminator 42 discriminates the actions of the user U by determining the output signal, and determines the state of the user U.

[0041] The storage device 43 stores arbitrary data such as a program for controlling the movement of the movement discrimination device 11 of this embodiment, various threshold values, etc. (see FIG. 1).

[0042] The discrimination device 42 transmits a signal to a terminal device 45 or receives a signal from the terminal device 45 via a network 44 such as the Internet or an intranet. The terminal device 45 is not particularly limited and may be a display device such as a liquid crystal display, a tablet terminal, a smartphone, or a terminal device 45 dedicated to the motion discrimination device 11 of this embodiment. The terminal device 45 receives the signal from the discrimination device 42 and notifies the user U of the state of the user U. The means for notifying is not particularly limited and any means may be used, such as a screen display or audio notification.

[0043] 3. User U's actions Next, the movements of the user U will be described with reference to Figures 6 to 10. The classification of the movements of the user U in the following description is merely an example, and the movements of the user U are not limited to the following classification.

[0044] FIG. 6 shows a state in which a user U is lying on a bed 20. In the state in which the user U is lying on the mattress 25 of the bed 20, with his / her head facing the headboard 21 and his / her feet facing the footboard 22. Furthermore, in FIG. 6, the user U is in a resting state, such as lying on the bed 20 while sleeping or awake and not moving on the bed 20. The resting state is included in the state in which the user is lying on the bed. Handrails 26 are arranged on both sides of the portion of the user U from the head to the waist in the state in which the user is lying on the bed. In this embodiment, a sensor 30 is arranged below the torso of the user U. In particular, from the viewpoint of improving detection accuracy, the position where the sensor 30 is arranged is preferably below the region between the armpits and waist of the user U, more preferably below the region between the armpits and navel, and even more preferably below the solar plexus.

[0045] When the user U is in bed, the sensor 30 detects pressure or vibration applied by the user U to the mattress 25 and outputs an output signal. In the bed-occupying state, examples of the pressure applied by the user U to the mattress 25 include pressure caused by the user U's breathing and pressure based on the user U's heartbeat.

[0046] The discrimination device 42 discriminates that the user U is in bed. The discrimination device 42 also notifies the terminal device 45 that the user U is in bed. However, the discrimination device 42 may or may not notify the terminal device 45 that the user U is in a resting state.

[0047] FIG. 7 shows an active state in which the user U is moving while lying on the bed 20. The active state includes states in which the user U turns over on the mattress 25 of the bed 20 or holds on to the handrail 26 as a preparatory action for sitting up. In the active state, the upper body of the user U is in contact with the mattress 25 of the bed 20. Since the user U in the active state is moving while lying on the bed 20, the active state is included in the in-bed state.

[0048] In the active state, examples of pressure applied by the user U to the mattress 25 include pressure due to the user U's body movements, pressure due to the user U's breathing, and pressure based on the user U's heartbeat.

[0049] The discrimination device 42 determines that the user U is in an active state. The discrimination device 42 according to this embodiment does not notify the terminal device 45 that the user U is in an active state. However, the discrimination device 42 may be configured to notify the terminal device 45 that the user U is in an active state.

[0050] 8 shows a state in which the user U sits upright on the bed 20. In the standing state, the user U sits upright on the mattress 25 of the bed 20. In the standing state, the user U's upper body is separated from the upper surface of the mattress 25.

[0051] In the standing up state, the pressure applied from the user U to the mattress 25 is, for example, pressure caused by the body movement of the user U. Pressure based on the breathing of the user U and pressure based on the heartbeat of the user U are not directly applied to the mattress 25. However, pressure based on the breathing of the user U and pressure based on the heartbeat of the user U may be indirectly applied to the mattress 25 from parts of the user U that come into contact with the mattress 25, such as the buttocks, feet, and hands.

[0052] The discrimination device 42 determines that the user U is in a standing up state. The discrimination device 42 also notifies the terminal device 45 that the user U is in a standing up state.

[0053] 9 shows a state in which the user U sits on the edge of the bed 20. In the edge-sitting state, the upper body of the user U is spaced apart from the top surface of the mattress 25.

[0054] When the user U is sitting on the edge of the mattress, the pressure exerted on the mattress 25 by the user U is, for example, pressure resulting from the user U's body movements. Furthermore, very small amounts of pressure based on the user U's breathing and pressure based on the user U's heartbeat are also exerted on the mattress 25. For this reason, the breathing signal or heartbeat signal may be determined to be "not detected." On the other hand, when the user U is sitting on the edge of the mattress, if pressure is exerted on the mattress 25 by movements such as rocking the body, the breathing signal or heartbeat signal may be determined to be "detected."

[0055] The discrimination device 42 according to this embodiment does not determine that the user U is sitting on the edge of the seat. Furthermore, the discrimination device 42 according to this embodiment does not notify the terminal device 45 that the user U is sitting on the edge of the seat. However, the discrimination device 42 may determine that the user U is sitting on the edge of the seat, or may notify the terminal device 45 that the user U is sitting on the edge of the seat.

[0056] 10 shows a state in which the user U has left the bed 20. In this state, the sensor 30 does not, in principle, detect pressure applied by the user U to the mattress 25. However, immediately after the user U leaves the bed 20, the mattress 25 may vibrate, applying pressure to the sensor 30 and causing the sensor 30 to output an output signal.

[0057] The discrimination device 42 determines that the user U is in a state of getting out of bed. The discrimination device 42 also notifies the terminal device 45 that the user U is in a state of getting out of bed.

[0058] 4. Signals The output signal and the signal generated by the arithmetic unit 41 will be described with reference to Figures 5(a) to 5(c). However, for the sake of convenience, the scale of the vertical axis of each graph in Figures 5(a) to 5(c) has been adjusted for each graph. Therefore, please note that it is not possible to compare the magnitude of the waveforms in each graph.

[0059] 5(a) shows an output signal. The output signal is a signal that the calculation device 41 receives from the sensor 30. The output signal is a single-channel signal that is output from the sensor 30. The output signal is a signal that corresponds to the amount of change in the load applied to the sensor 30. The output signal includes a signal caused by the body movement of the user U, a signal caused by the breathing of the user U, a signal caused by the heartbeat of the user U, a signal caused by the pulse of the user U, etc.

[0060] FIG. 5(b) shows the heartbeat frequency signal. The calculation device 41 generates the heartbeat frequency signal by applying a bandpass filter to the output signal, which passes frequency components corresponding to signals caused by the heartbeat of the user U. The bandpass filter passes frequency components of 9 to 15 Hz. The frequency band of vibrations (ballistocardiograms) caused in the human body by heartbeats is said to be approximately several Hz to 20 Hz, and by passing the above-mentioned 9 to 15 Hz frequency components of the output signal, the signal caused by the heartbeat of the user U can be clearly detected. The discrimination device 42 detects the heartbeat of the user U based on the heartbeat frequency signal, and transmits a signal related to the heartbeat to the terminal device.

[0061] FIG. 5(c) shows the respiratory frequency signal. The calculation device 41 generates the respiratory frequency signal by integrating the output signal with the oscillation center of the output signal as a baseline BL. Specifically, the oscillation center of the output signal is defined as the baseline BL, and the portion above the baseline BL is integrated with a positive sign, while the portion below the baseline BL is integrated with a negative sign. The frequency band of signals caused by body movements such as turning over in bed is generally said to be approximately 2 Hz or less, which is closer to the frequency band of the respiratory component than the frequency band of the heartbeat frequency signal. Integration has a low-pass effect, allowing the respiratory component to be clearly captured. However, the calculation device 41 may also generate the respiratory frequency signal by using a low-pass filter that passes components corresponding to the signal caused by breathing. The discrimination device 42 detects the user U's breathing based on the respiratory frequency signal and transmits a signal related to breathing to the terminal device.

[0062] Next, the output signal will be described with reference to Fig. 5(a). In the graph shown in Fig. 5(a), the output signal (first signal) in the first region A shows a relatively regular waveform. A user U in this state is considered to be lying quietly on the bed 20 (see Fig. 6). The output signal in the first region A is a resting signal output when the user U is lying quietly on the bed 20. The regular waveform shown in the graph of the resting signal is considered to be a signal caused by breathing and a signal caused by heartbeat.

[0063] In the graph shown in FIG. 5(a), the output signal (second signal) in the second region B has a larger amplitude and a more distorted waveform than the waveform in the first region A. It is thought that the user U in this state is lying on the bed 20 and turning over in his sleep or grabbing the handrail 26 in an attempt to stand up (see FIG. 7). The output signal in the second region B is an active signal that is output in an active state in which the user U moves while lying on the bed 20. The waveform shown in the graph of the active signal is thought to be a signal resulting from the movements of the user U.

[0064] 5(a), the output signal (third signal) in the third region C has one peak P at the boundary between the second region B and the third region C, and this peak P gradually attenuates to an amplitude of 0. In this embodiment, the waveform of the output signal that includes the peak P is referred to as a rising signal S.

[0065] In this embodiment, the amplitude of the output signal in the region before the peak P is larger than the amplitude in the region after the peak P. Specifically, the amplitude of the output signal in the second region B is larger than the amplitude of the output signal in the third region C. This allows the rising signal S to be clearly distinguished.

[0066] The rising signal S also has an increase region D where the output signal increases toward the peak P, and an attenuation region E where the output signal attenuates beyond the peak P. The absolute value of the decrease in the rising signal S per unit time in the attenuation region E is smaller than the absolute value of the increase in the rising signal S per unit time in the increase region D. In other words, the rising signal S increases sharply in the increase region D before the peak P, and attenuates gradually in the attenuation region E after the peak P. This allows the rising signal S to be clearly distinguished.

[0067] It is considered that a user U in a state in which a rise signal S is output has sat up on the bed 20 and is in a standing state (see FIG. 8). One peak P observed at the boundary between the second region B and the third region C is a signal resulting from pressure applied to the mattress 25 when the user U stands up. The gradual attenuation of the peak P is considered to be due to the mattress 25 vibrating due to the applied pressure, and the gradual attenuation of this vibration.

[0068] 5(a) shows that the rising signal S including the peak P has a single waveform that gradually decays, whereas the waveform of the resting signal detected in the first region A oscillates regularly. In this respect, the peak P of the rising signal S is distinguished from the waveform of the resting signal.

[0069] Furthermore, peak P in Figure 5(a) is a single peak that gradually decays, whereas the waveform of the active-time signal detected in second region B oscillates irregularly and has sharp peaks. In this respect, peak P related to rising signal S is distinguished from the waveform of the active-time signal. Peak P related to rising signal S is detected after the active-time signal is detected, detection of the active-time signal continues, and then the active-time signal becomes undetected.

[0070] 5(a) and the heartbeat frequency signal in FIG. 5(b), the peak P of the rising signal S is detected after the heartbeat frequency signal becomes undetectable at the boundary between the second region B and the third region C. This makes it possible to distinguish the peak P related to the rising signal S.

[0071] As described above, by distinguishing the peak P related to the rising signal S from the output signal and detecting this peak P related to the rising signal S, it is possible to determine that the user U is in a rising state.

[0072] Assumed states corresponding to the third region C in FIG. 5(a) are when the user U is in a sitting position as shown in FIG. 8 and when the user U is in a sitting position as shown in FIG. 9. In these cases, the user U is away from the mattress 25 of the bed 20. Therefore, the sensor 30 cannot directly detect the pressure based on the heartbeat and the pressure based on the breathing of the user U. However, the sensor 30 detects the pressure applied to the mattress 25 in accordance with the movement of the user U's body from the part of the user U's body that is in contact with the mattress 25 of the bed 20.

[0073] When the user U is in a sitting position or sitting on the edge of the bed 20, the pressure applied by the user U to the mattress 25 of the bed 20 causes the sensor 30 to output an output signal. This output signal may contain frequency components corresponding to signals caused by breathing and frequency components corresponding to signals caused by heartbeats.

[0074] As described above, even when the user U has finished moving, if the mattress 25 vibrates due to the pressure applied to the mattress 25 by the user U, a frequency component corresponding to the heartbeat may be detected in the damped portion of this vibration. Therefore, after detecting the peak P of the sit-up signal S, the discrimination device 42 determines that the user U is in an out-of-bed state if no output signal is detected for a predetermined period of time (see FIG. 5(a)).

[0075] 5. Effects of this form Next, the effects of this embodiment will be described. The movement determination system 10 according to this embodiment includes a bed 20 and a movement determination device 11 that determines the movement of a user U on the bed 20. The movement determination device 11 includes a sensor 30 that detects changes in the load applied by the user U and a determination device 42 that receives an output signal from the sensor 30 and determines the movement of the user U. The bed 20 includes a bed body 20a and a mattress 25 placed on the bed body 20a. The sensor 30 is formed in a strip shape and is disposed between the bed body 20a and the mattress 25, and is disposed in a position corresponding to the torso of the user U when the user U is lying on the mattress 25. The determination device 42 determines, based on the output signal, whether the user U has raised their upper body on the bed 20. According to this embodiment, the rising state can be determined before the user U gets out of the bed 20.

[0076] The discrimination device 42 according to this embodiment determines whether the output signal contains a rising signal S output by the sensor 30 when the user U sits up on the bed 20, and determines that the user U is in a rising state if the output signal contains the rising signal S. This makes it possible to determine the rising state of the user U.

[0077] The sensor 30 according to this embodiment detects vibrations of the mattress 25 caused by the movements of the user U. This allows the sensor 30 to detect the movements of the user U on the bed 20 even when the user U is not vertically above the sensor 30.

[0078] In this embodiment, the bed 20 is set with a head-foot direction including the head and foot sides of the user U when the user U is lying down, and it is preferable that the width dimension of the sensor 30 in the head-foot direction when the user U is in bed is shorter than the length of the user U's torso.

[0079] The sensor 30 is preferably placed in a position corresponding to the area between the shoulders and waist of the user U when the user U is lying on the bed 20. This allows the movement of the user U to be detected with high accuracy. Furthermore, the sensor 30 is more preferably placed in a position corresponding to the area between the armpits and waist of the user U when the user U is lying on the bed 20. This allows the movement of the user U to be detected with higher accuracy.

[0080] The bed body 20a according to this embodiment includes a frame and a bed board placed on the frame. The sensor 30 is fixed to the upper surface of the bed board. This prevents the location of the sensor 30 from changing due to the movements of the user U or the movement of sheets, blankets, or comforters. As a result, changes in the detection accuracy of the movements of the user U on the bed 20 can be prevented.

[0081] (Embodiment 2) Next, a second embodiment will be described with reference to Fig. 5 and Fig. 11. Fig. 11 shows a flowchart relating to a process for determining the standing-up state.

[0082] When the process of determining the standing-up state is executed, the determination device 42 acquires an output signal shown in FIG. 5 (S1).

[0083] The discriminator 42 analyzes the acquired output signal and determines whether a first region A including a first signal that oscillates relatively regularly has occurred (S2). If the calculator 41 determines that the first region A has occurred (S2: Y), it analyzes the output signal and determines whether a second region B including a second signal that has a larger amplitude and a more disturbed waveform than the first signal has occurred (S3).

[0084] If the second region B occurs (S3: Y), the discriminator 42 analyzes the output signal and determines whether the third region C including the gradually attenuating third signal has occurred (S4).

[0085] If the third region C occurs (S4: Y), the discriminator 42 determines whether the amplitude of the first signal is greater than the amplitude of the third signal (S5).

[0086] If the discriminator 42 determines that the amplitude of the first signal is greater than the amplitude of the third signal (S6: Y), it determines that the user U is in a standing-up state (S6). This completes the process of discriminating between the standing-up state and the non-standing-up state.

[0087] On the other hand, if the discriminator 42 determines that the first region A has not occurred (S2: N), it repeats the process of S2.

[0088] Furthermore, when the discriminator 42 determines that the second region B has not occurred (S3: N), it repeats the processes of S2 to S3.

[0089] Furthermore, when the discriminator 42 determines that the third region C has not occurred (S4: N), it repeats the processes of S3 to S4.

[0090] Furthermore, when the discriminator 42 determines that the amplitude of the first signal is not greater than the amplitude of the third signal (S5: N), it repeats the processes of S2 to S5.

[0091] This completes the process of determining whether the user is in the standing-up state.

[0092] Note that, among the symbols used in the second and subsequent embodiments, the same symbols as those used in the previous embodiments represent the same components, etc. as those in the previous embodiments, unless otherwise specified.

[0093] According to this embodiment, even if the peak P of the rising signal S is unclear between the second region B and the third region C, it is possible to determine whether the user U is in a rising state.

[0094] The present invention is not limited to the above-described embodiments, and can be applied to various embodiments within the scope of the present invention. [Explanation of symbols]

[0095] 10: Motion discrimination system, 11: Motion discrimination device, 20: Bed, 20a: Bed body, 24: Floor board, 25: Mattress, 27: Restraint member, 30: Sensor, 31: Base material, 32: Elastic body, 33: Sensor sheet, A: First region, B: Second region, C: Third region, D: Increase region, E: Decrease region, P: Peak, S: Standing up signal, U: User

Claims

1. A motion determination system including a bed and a motion determination device that determines the motion of a user on the bed, The movement determination device includes: a sensor that detects a change in the load applied by the user; a determination device that receives an output signal from the sensor and determines the user's action, The bed is The bed itself, and a mattress placed on the bed body, The sensor The support member is formed in a belt shape, and is disposed between the bed body and the bedding, and is disposed at a position corresponding to the torso of the user when the user is lying on the bedding, The discrimination device is a motion discrimination system that discriminates whether the user has raised his or her upper body on the bed based on the output signal.

2. The discrimination device is determining whether the output signal includes a rising signal output by the sensor when the user sits up on the bed; The motion determination system according to claim 1 , wherein the system determines that the user is in the standing-up state on the condition that the standing-up signal is included in the output signal.

3. the rising signal has one peak; The motion determination system according to claim 2 , wherein the amplitude of the output signal in a region before the peak is greater than the amplitude of the output signal in a region after the peak.

4. the rising signal has one peak; the rising signal has an increasing region in which the output signal increases toward the peak, and an attenuation region in which the output signal attenuates beyond the peak, The motion determination system according to claim 2 , wherein an absolute value of a decrease in the rising signal per unit time in the attenuation region is smaller than an absolute value of an increase in the rising signal per unit time in the increase region.

5. The output signal is a first region from which a first signal exhibiting a relatively regular waveform is output; a second region in which a second signal having a larger amplitude than the first signal and a more distorted waveform than the first signal is output; a third region in which a third signal that gradually attenuates is output; The discrimination device is 2. The motion determination system according to claim 1, wherein when the second region occurs after the first region and the third region occurs after the second region, the system determines that the user is in a sitting-up state on the condition that the amplitude of the first signal is smaller than the amplitude of the third signal.

6. the output signal includes a heartbeat frequency signal having a frequency component corresponding to a signal caused by the heartbeat of the user U; The motion determination system according to claim 2 , wherein the rising signal is detected in a state in which the heartbeat frequency signal is not detected.

7. The output signal is a resting state signal output when the user U is lying on the bed in a resting state; an active state signal that is output when the user U is in an active state while lying on the bed and moving; the resting signal has a waveform that oscillates regularly, and the active signal has a waveform that oscillates irregularly; The motion determination system according to claim 1 , wherein the determination device detects irregular vibrations in the waveform of the output signal and determines that the user is in the active state.

8. The output signal includes an active-time signal that is output in an active state in which the user U is moving while lying on the bed, the active signal has an irregularly oscillating waveform, the rising signal has one peak with a waveform that is gentler than the active signal; The motion detection system according to claim 2 , wherein the rise signal is detected after the active signal is detected.

9. The movement determination system according to claim 1 , wherein the sensor detects vibrations of the mattress caused by the movement of the user.

10. a head-foot direction including a head side and a foot side of the user when the user is lying down is set in the bed; The movement determination system according to claim 1 , wherein a width dimension of the sensor in the head-to-foot direction in the in-bed state is shorter than a torso length of the user.

11. The movement determination system according to claim 1 , wherein the sensor is disposed at a position corresponding to a position between the shoulders and waist of the user when the user is lying on the bed.

12. The movement determination system according to claim 1 , wherein the sensor is disposed at a position corresponding to a position between the armpit and the waist of the user when the user is lying on the bed.

13. The bed body includes: The frame and a floor plate placed on the frame, The motion determination system according to claim 1 , wherein the sensor is fixed to an upper surface of the floorboard.

14. The motion determination system according to claim 13 , wherein both ends of the sensor are fixed to the floorboard.

15. a head-foot direction including a head side and a foot side of the user when the user is lying down is set in the bed; The bed further comprises: A bed exit restriction member is provided on at least one side edge of the bed in a direction intersecting the head-foot direction and on the head side of the head-foot direction, which restricts the user from exiting the bed, The movement determination system according to claim 1 , wherein a bed exit area where the user can exit the bed is set on the foot side of the bed in the head-to-foot direction.

16. a head-foot direction including a head side and a foot side of the user when the user is lying down is set in the bed, 2. The movement determination system of claim 1, wherein when the sensor is placed on the bed, the length dimension of the sensor in the left-right direction intersecting the head-to-foot direction is 80% or more of the width dimension in the left-right direction.

Images