JP2004081632A - Method and apparatus for monitoring human operating condition - Google Patents

Abstract

A highly reliable operation state monitoring system is realized by automatically and accurately determining a static state, a dynamic state, a stable state or a dangerous state, and furthermore, the contents of static and dynamic states.
Kind Code: A1 An acceleration is measured by an accelerometer, and it is determined whether the state is a static state or a dynamic state based on the magnitude of change in acceleration in each direction during a predetermined time. In the dynamic state, the state is further stabilized by the magnitude of change in acceleration. Determine whether the state is dangerous or dangerous. The posture in the static state is determined based on the value of the acceleration in each direction, and the operation state in the dynamic state is determined by waveform analysis from the magnitude of the change in acceleration.
[Effect] The elderly and the like can freely act with peace of mind, and in the event of an emergency, quick rescue activities are performed and the burden on the caregiver is significantly reduced.
[Selection diagram] Fig. 4

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention attaches a sensor to a human body to determine whether the person is in a static state or a dynamic state, and whether the person is in a danger state or a stable state, and furthermore, each specific state. The present invention relates to a method and apparatus for automatically determining with high accuracy.
[0002]
[Prior art]
The declining birthrate and aging are rapidly progressing, and the care of the elderly in particular is becoming a social problem. Some people in need of care should be accompanied when going out because they may be lost or fall suddenly. Even now, even if nursing is not required, some people are not confident in their free behavior due to physical weakness and tend to stay at home. The latter are also referred to as those who need nursing care and are likely to increase the burden of nursing care in the near future.
[0003]
It is a social responsibility to allow these people to be free to go out and to have the joy of living, especially to allow the latter to contribute to society again. For that purpose, a system is required that can monitor the operation state of a person while protecting privacy, and can immediately rush to rescue when a dangerous state is predicted or becomes dangerous.
[0004]
Such a system has been conventionally proposed, and a sensor using an accelerometer is known as a sensor that is worn on a human body to monitor the operating state of the person.
Journal of the Japan Society of Mechanical Engineers, 1996. Vol. 101 No. At 950 p14-16, a biaxial acceleration sensor is attached to the waist of the human body, and based on changes in the acceleration in the body axis direction and the longitudinal direction, the person is standing, sitting, lying, or walking. It is shown whether the user is riding on a train, a car, or a bicycle.
Japanese Patent Laid-Open Publication No. Hei 10-295649 discloses a three-axis acceleration sensor, which detects walking, running, standing still, and falling from three-axis acceleration changes in vertical, longitudinal, and lateral directions. The judgment is shown.
[0005]
[Problems to be solved by the invention]
According to the technique of the above-mentioned known document, the acceleration change in two axes or three axes is measured. However, it is not possible to sufficiently obtain a specific operation state of a person, particularly a determination accuracy of whether the state is a stable state or a dangerous state, In addition, the judgment accuracy of the specific contents of the dynamic state and the static state was not sufficiently obtained, and there was a problem in reliability.
[0006]
Therefore, a problem to be solved by the present invention is to attach a sensor to a human body, determine whether the person is in a static state or a dynamic state, and whether the person is in a stable state or in a dangerous state, Highly reliable operating state by accurately and accurately determining specific dynamic states such as walking, running, climbing stairs, standing, squatting, lying upside down, lying down, lying down, etc. It is to realize a monitoring system.
[0007]
[Means for Solving the Problems]
According to the method of the present invention for solving the above-mentioned problem, an accelerometer is attached to a human body, acceleration obtained from each measurement axis is measured by the accelerometer, and the acceleration is measured in a static state according to the magnitude of the change in acceleration in a predetermined time. It is determined whether the vehicle is in a dynamic state or a dynamic state. When the vehicle is determined to be in a dynamic state, it is further determined whether the state is a stable state or a dangerous state based on the magnitude of the change in acceleration. This is an operation state monitoring method.
[0008]
In addition, an acceleration clock having three or more measurement axes is attached to the human body, and the acceleration obtained from each measurement axis is measured by the accelerometer. It is determined whether the vehicle is in a dynamic state. If the vehicle is determined to be in a dynamic state, it is further determined whether the vehicle is in a stable state or a dangerous state according to the magnitude of the change in acceleration, and the falling direction of the human body is estimated. This is a method for monitoring the operation state of a person.
[0009]
In the above method of the present invention, when the static state is determined, the posture of the static state is further determined from the value of acceleration, and when the dynamic state is determined, the waveform analysis is further performed based on the magnitude of the change in acceleration. Thus, the operation status can be determined.
[0010]
The device of the present invention for solving the above problems comprises a terminal mounted on a human body, a monitoring device installed in a monitoring center, and wireless communication means from the terminal to the monitoring device, wherein the terminal is an accelerometer and a measurement result. A monitoring means, a monitoring means, a receiving means from the terminal, a mechanism for determining whether the state is a static state or a dynamic state according to the magnitude of the change of the acceleration in a predetermined time, and a monitor of the acceleration A human operation state monitoring device having a mechanism for determining whether the state is a stable state or a dangerous state based on the magnitude of a change.
[0011]
In addition, it consists of a terminal mounted on the human body, a monitoring device installed at the monitoring center, and a wireless communication means from the terminal to the monitoring device. The terminal is an accelerometer, a portable terminal for analyzing the measurement result, and a transmission of the analysis result. The monitoring device has a receiving device from the terminal device and a host computer, and the portable terminal and the host computer share the monitoring device, and the monitoring device is in a static state or a dynamic state depending on the magnitude of the acceleration change in a predetermined time. A human operation state monitoring device comprising: a mechanism for determining whether the state is a state; and a mechanism for determining whether the state is a stable state or a dangerous state based on the magnitude of a change in acceleration.
[0012]
The above-described device of the present invention may further include a mechanism for estimating the falling direction of the human body from the magnitude of the change in acceleration obtained from each measurement axis. Furthermore, a mechanism for determining the posture in the static state from the value of the acceleration and a mechanism for determining the operation state in the dynamic state by waveform analysis from the magnitude of the change in the acceleration may be provided.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
According to the method of the present invention, an accelerometer is attached to a human body, and a motion state of the person is determined based on a measured value of acceleration obtained from each measurement axis. In the determination, first, whether the state is the static state or the dynamic state is determined based on the magnitude of the change in the acceleration during a predetermined time, and then, if the state is determined to be the dynamic state, the change in the acceleration is further stabilized by the magnitude. It is determined whether the state is a state or a dangerous state.
[0014]
In the examples of FIGS. 1 and 2, the two-axis accelerometer 2 is attached to the human body, and the direction of gravity (Y-axis direction) and the traveling direction (X-axis direction) perpendicular to the direction of gravity are taken as measurement axes. Measuring acceleration.
FIG. 3 shows a measurement example. 3A shows the acceleration in the Y direction, and FIG. 3B shows the acceleration in the X direction. In both figures, A is a standing and stationary state, B is a running state, C is a walking state, D is a stopped state, E is a squatting state, F is a squatting and stationary state, G is a state of falling down, and H is a state of lying prone.
[0015]
As described above, the accelerations in the Y direction and the X direction show a specific change according to the operation state. In the static state of A, D, F, and H, it is small, and in the dynamic state of B, C, E, and G, it is large. However, the manner of change differs depending on various operation situations and individual differences.
In the present invention, it is first determined whether the vehicle is in the static state or the dynamic state based on the magnitude of the change in the acceleration in the X direction and the Y direction in the predetermined time.
[0016]
Then, when it is determined that the vehicle is in the dynamic state, it is determined whether the vehicle is in a dangerous state such as a state in which G falls down or in a stable state such as a state in which C walks according to the magnitude of the change in acceleration in the X direction. judge. The transition from the dynamic state to the static state is likely to be dangerous. When it is determined that the vehicle is in a dangerous state, as shown in FIGS. 1 and 2, a warning is issued by a warning device 10 or the like from a monitoring device 5 placed in a house or a hospital, and a rescue operation 11 can be performed.
[0017]
An example of the determination according to the method of the present invention is shown in the flowchart of FIG. In this example, the X-axis and Y-axis acceleration signals measured by the two-axis accelerometer are fetched for 5 seconds, and the magnitude of the change in the X-direction acceleration Δx / Δt ₁ and the acceleration change in the Y-direction during the predetermined time Δt ₁ If the magnitude Δy / Δt ₁ is 0.5 G or less, it is determined to be a static state, and if it exceeds 0.5, it is determined to be a dynamic state.
[0018]
When it is determined that the dynamic state exceeds 0.5, the magnitude of the change in acceleration in the X direction Δx / Δt ₂ during the predetermined time Δt ₂ is 0.5 G or more and the X direction in the X direction during the predetermined time Δt ₃ is further determined. When the absolute value of the magnitude of the change in acceleration Δx / Δt ₃ is 1 G or more, it is determined that the state is dangerous and an alarm is issued. In this example, Δt ₁ , Δt ₂ , and Δt ₃ are set to 0.5 seconds, 0.5 seconds, and 0.1 seconds, respectively.
[0019]
The determination as to whether the state is the dangerous state or the stable state can be made based on the value of one measurement axis having a large change in acceleration when shifting from the dynamic state to the static state, as in this example. Further, it is also possible to carry out in one step instead of two steps as in this example. For example, the determination may be made only based on whether or not the absolute value of the magnitude Δx / Δt ₃ of the change in the acceleration in the X direction at Δt ₃ in the subsequent stage is 1 G or more.
[0020]
In addition, the acquisition time of the acceleration signal from the two-axis accelerometer, the values of Δt ₁ , Δt ₂ , Δt ₃ , and the reference value of the magnitude of the acceleration change are appropriately determined according to the characteristics and the operation state of each individual to be worn. By setting the value, the determination accuracy can be improved. The appropriate value can be determined by an individual test. It is preferable to use XY-direction acceleration data when falling down. However, for a weak person such as an elderly person, the speed can be changed in a walking state or can be determined based on data in a case of squatting from a standing state.
[0021]
Further, in the example of FIG. 3, the determination of the static state or the dynamic state is performed every 30 minutes. However, the determination interval can be appropriately set according to each individual and the behavioral situation. For example, the determination interval can be reduced for a person who is likely to be in a dangerous state.
According to the method of the present invention, by predetermining appropriate conditions in accordance with individual cases in this way, it is possible to make a highly accurate determination applicable to various individuals who take various actions.
[0022]
In the method of the present invention, an accelerometer having three or more measurement axes may be mounted, and the falling direction of the human body may be estimated from the magnitude of the acceleration change of each measurement axis. For example, by measuring not only the X direction and the Y direction but also the lateral direction using a three-axis accelerometer, it is possible to estimate whether the vehicle has fallen forward, backward, right, or left.
[0023]
Further, in the method of the present invention, specific contents of the static state and the dynamic state can be determined. In the static state, as shown in FIG. 6, (a) standing position, (b) sitting position, (c) crouching position, (d) downward lying position, (e) upward lying position, (f) sideways lying position, etc. In the posture and the dynamic state, as shown in FIG. 7, (g) stop, (h) walk, (i) run, and (j) climb up and down stairs.
[0024]
The posture in the static state can be determined from the value of the acceleration of each measurement axis. When a two-axis accelerometer is used, the determination can be made based on XY coordinate plots of X-direction acceleration and Y-direction acceleration. For example, as shown in FIG. 9, the region of each posture may be set in advance by using the fact that plots are collected in a specific region according to the posture.
[0025]
The operation state of the dynamic state can be determined by waveform analysis from the magnitude of the change in the acceleration of each measurement axis. In the waveform analysis, as in the example shown in the flow of FIG. 4, the cycles of the waveforms in the X and Y directions are obtained by FFT (Fast Fourier Transform method), and the PP value in each cycle is obtained as shown in FIG. XY coordinate plotting. For example, as shown in FIG. 8, areas corresponding to each state can be set in advance.
[0026]
In the present invention, the position of the accelerometer worn on the human body is preferably the waist in a normal walking or running state, but depending on the circumstances and characteristics of the individual, the characteristics of the behavior, etc., the toes, legs, knees, arms, head, etc. In some cases, it is better to wear it. In accordance with each, it is preferable to attach to a site where determination can be made with the highest accuracy.
[0027]
Next, as shown in the example of FIG. 1, the device of the present invention comprises a terminal 1 mounted on a human body, a monitor 5 installed at a monitoring center, and a wireless communication means from the terminal 1 to the monitor 5; The terminal 1 has an accelerometer (in this example, a two-axis accelerometer 2) and a transmitter 4, and the monitor 5 has a receiver 6 from the terminal 1 and a host computer 7.
[0028]
The accelerometer (two-axis accelerometer 2) 2 measures the acceleration in each measurement axis (X axis, Y axis) direction as described above. As described above, the host computer 7 determines whether the state is the static state or the dynamic state based on the magnitude of the change in the acceleration in the X direction and the Y direction in the predetermined time, and the change in the acceleration in the X direction. Has a mechanism for determining whether it is in a stable state or in a dangerous state depending on the size of. In FIG. 1, the input device 8 inputs appropriate values according to the characteristics of each individual for a predetermined time required for determination, a magnitude of a change in reference acceleration, and the like.
[0029]
Further, in the apparatus of the present invention, as shown in the example of FIG. 2, the terminal 1 has the portable terminal 3, and the respective determination mechanisms can be shared between the portable terminal 3 and the host computer 7. All the determinations can be made by the mobile terminal 3 and the host computer 7 can only input the appropriate values, display the results, and issue the alarm.
[0030]
In the device of the present invention, the portable terminal 3 and the computer 7 can further have a mechanism for estimating the falling direction of the human body. Further, a mechanism for determining a posture in a static state and a mechanism for determining an operation state in a dynamic state can be further provided.
At the time of the rescue operation 11 when it is determined to be in a dangerous state, the location of the target person who goes to rescue can be detected by using position information by PHS or GPS.
[0031]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, a weak person, such as an elderly person, can go out freely with confidence, such as going out alone. Privacy is protected and emergency relief is provided in case of emergency. Therefore, caregivers need to be given the joy of living, and can provide social contribution opportunities for those who tend to be withdrawn. In addition, the burden on the caregiver is significantly reduced.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing an example of a monitoring system according to the present invention.
FIG. 2 is an explanatory diagram showing another example of the monitoring system according to the present invention.
FIGS. 3A and 3B are graphs showing measurement examples of acceleration in the present invention.
FIG. 4 is a flowchart illustrating an example of the present invention.
FIG. 5 is a graph showing an example of waveform analysis in the present invention.
FIGS. 6A to 6F are explanatory diagrams showing examples of a static state to be determined in the present invention.
FIGS. 7 (g) to (j) are explanatory diagrams showing examples of dynamic states targeted by the present invention.
FIG. 8 is a graph showing an example of an XY coordinate plot according to the present invention.
FIG. 9 is a graph showing another example of the XY coordinate plot in the present invention.
[Explanation of symbols]
1: terminal 2: two-axis accelerometer 3: portable terminal 4: transmitter 5: monitor 6: receiver 7: host computer 8: input 9: display 10: alarm 10: rescue operation

Claims (7)

Wearing an accelerometer on the human body, measuring the acceleration obtained from each measurement axis by the accelerometer, and determining whether the state is a static state or a dynamic state by the magnitude of the change in acceleration in a predetermined time, A method for monitoring a human operation state, comprising determining whether the state is a stable state or a dangerous state based on the magnitude of a change in acceleration when the dynamic state is determined. An accelerometer with three or more measurement axes is attached to the human body, and the acceleration obtained from each measurement axis is measured by the accelerometer. It is determined whether the vehicle is in a state or not. Characteristic method of monitoring the operating state of a person. When it is determined to be in the static state, the posture in the static state is further determined from the value of the acceleration, and when it is determined to be in the dynamic state, the operation state is further determined by waveform analysis from the magnitude of the change in acceleration. 3. The method according to claim 1, further comprising the steps of: It consists of a terminal mounted on the human body, a monitoring device installed at the monitoring center, and a wireless communication means from the terminal to the monitoring device, wherein the terminal has an accelerometer and a transmission means of the measurement result, and the monitoring device is Receiving means from the terminal, a mechanism for determining whether the state is a static state or a dynamic state according to the magnitude of change in acceleration in a predetermined time, and whether the state is stable or dangerous depending on the magnitude of change in acceleration A device for monitoring the operation state of a human being, comprising a mechanism for determining whether or not the operation status is human. It consists of a terminal mounted on the human body, a monitoring device installed at the monitoring center, and a wireless communication means from the terminal to the monitoring device.The terminal includes an accelerometer, a mobile terminal for analyzing the measurement result, and a transmission means for the analysis result. The monitoring device has a receiving means from the terminal device and a host computer, and the mobile terminal and the host computer share, and the monitoring device is in a static state or a dynamic state depending on the magnitude of change in acceleration in a predetermined time. A human operation state monitoring device, comprising: a mechanism for determining whether there is an object; and a mechanism for determining whether the state is a stable state or a dangerous state based on the magnitude of a change in acceleration. 6. The apparatus according to claim 4, further comprising a mechanism for estimating a falling direction of a human body from a magnitude of a change in acceleration obtained from each measurement axis. 7. The system according to claim 4, further comprising: a mechanism for determining a posture in a static state from a value of the acceleration, and a mechanism for determining an operation state in a dynamic state by waveform analysis from a magnitude of a change in the acceleration. The operating state monitoring device of the described person.

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