JP2831619B2 - Body sway meter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a center of gravity sway meter, and more particularly, to a center of gravity sway meter having a function of determining that the center of gravity of a subject has stabilized before starting the center of gravity measurement.

[0002]

2. Description of the Related Art Conventionally, when a subject's center of gravity is measured using a body sway meter while the subject is standing still, the subject is placed on a detection table for measurement and becomes stable. After that, measurement was started.

[0003] To determine whether or not the subject is on a detection stand for measurement and has become stable, the measurer observes the subject on the detection stand and visually confirms the stability. Checking often starts measurement.

[0004]

However, in the above-mentioned conventional center-of-gravity sway meter, it is determined whether or not the subject is in a stable state by riding on the measuring detection table. However, there is a problem as described below because the observation of the subject on the detection table and the confirmation of stability by visual observation are started.

That is, when quantitative analysis is performed using a conventional body sway meter, it is necessary to provide objective measurement data. However, in the above-described steady state determination method, the measurement start time depends on the subject's subjectiveness. Is determined, there is a possibility that the objectivity of the measurement data may be impaired, and there arises a problem that the quantitative analysis is hindered.

SUMMARY OF THE INVENTION It is an object of the present invention to determine the steady state before the start of measurement in a body sway meter based on a predetermined criterion, and to determine the measurement start time objectively rather than subjectively. It is to provide a center of gravity sway meter that can be used.

According to the first aspect of the present invention, the load of the subject
A detecting table for detecting the cloth ; calculating means for sequentially determining the center of gravity of the subject from the distribution of the load detected by the detecting table by predetermined calculation processing; and a center of gravity of the subject based on the center of gravity sequentially determined by the calculating means. Analysis means for analyzing a change in the weight of the body .
Of the subject's center of gravity based on the subject's center of gravity
Speed calculating means for calculating a moving speed at predetermined time intervals;
Speed of the subject's center of gravity calculated by the speed calculation means
Standard deviation calculation for sequentially calculating the standard deviation of degrees
Means and the standard deviation calculated by the standard deviation calculating means.
It is determined that the difference is smaller than a predetermined determination value.
To confirm that the subject's center of gravity has stabilized
Discriminating means and the subject's center of gravity is stabilized by this discriminating means
If it is confirmed that the
Analysis control means for starting an analysis of a change in the center of gravity of the examiner;
It is characterized by having.

According to the center-of-gravity fluctuation meter of the present invention, a detection table for detecting the distribution of the load of the subject, and the center of gravity of the subject from the distribution of the load detected by the detection table are calculated by a predetermined calculation process. In a center of gravity sway meter having sequentially calculated arithmetic means and an analysis means for analyzing a change in the center of gravity of the subject based on the center of gravity sequentially determined by the arithmetic means, the speed is calculated by the speed calculating means.
The moving speed of the subject's center of gravity is determined based on the subject's center of gravity.
It is calculated at regular intervals and the calculated center of gravity of the subject is shifted.
For the dynamic speed, the standard deviation is calculated by the standard compilation calculation means.
Are sequentially calculated, and the calculated standard deviation is set in advance.
Is determined by the determining means to be smaller than the determined determination value.
This confirms that the subject's center of gravity has stabilized,
If the subject's center of gravity is confirmed to be stable,
Of the subject's center of gravity by the analysis means
Start analysis of.

Therefore, as compared with the conventional case where the measurer observes the subject on the detection table and visually confirms the stability to start the measurement, the measurement start condition is set under a certain condition. The determination can be made, the objectivity of the measurement data can be obtained, and the quantitative analysis can be performed. As a result, the operability and reliability of the sway meter can be improved.

In this case, as in the second aspect of the present invention, in the gravity center sway meter according to the first aspect, the discrimination value is movement data of the center of gravity obtained from a large number of subjects having different ages and genders. It is effective to determine based on.

According to the gravity center sway meter of the invention, the discrimination value is obtained based on the movement data of the center of gravity obtained from many subjects having different ages and genders.

Therefore, the judgment value for judging the stability of the center of gravity of the subject is sufficiently reliable, and the above-described steady state judgment processing is sufficiently reliable.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIGS. 1 to 11 show an embodiment of a center of gravity sway meter to which the present invention is applied.

First, the configuration will be described.

FIG. 1 is a block diagram showing a configuration of a main part of a gravity center sway meter 1 according to the present embodiment. In FIG. 1, the sway meter 1 includes a detection table 2, a signal amplifier 3, an A / D converter 4, an arithmetic device 5, a display device 6, and a printing device 7.

The detection table 2 is provided with load sensors S1 to S3 for detecting a load at each vertex when the subject is put on the detection table 2, and is detected by the load sensors S1 to S3. Each load is output to the signal amplifier 3 as a load detection signal.

The signal amplifier 3 amplifies each load detection signal to a predetermined level and converts the load detection signal input from the detection table 2 into a signal level that can be processed by each block in the subsequent stage. 4 is output.

The A / D converter 4 converts each load detection signal input from the signal amplifier 3 into digital data that can be processed by the arithmetic unit 5, and converts each load detection signal into predetermined load data. The data is converted and output to the arithmetic unit 5.

The arithmetic unit 5 has a CPU (Central Processi
ng Unit), ROM (Read Only M-emory) and RAM
(Random Access Memory) and has the functions shown in FIGS. FIG. 2 is a diagram showing a functional configuration of the arithmetic unit 5, and in FIG.
A load detection function for detecting each load from each load data input from the converter 4, a center of gravity calculation function for calculating a center of gravity from each of the detected loads, and a center of gravity calculation result for storing the calculated center of gravity calculation result It has a storage function, an analysis function for analyzing the stored center-of-gravity calculation result, a display function for displaying the analysis result on the display device 6, and a printing function for printing the analysis result on the printing device 7.

FIG. 3 is a diagram showing details of the center-of-gravity calculation function of FIG. In FIG. 3, the arithmetic unit 5 has an A /
A start method selection function for selecting a start method for starting the calculation before calculating the center of gravity from each load data input from the D converter 4, a manual start detection function for detecting the selected start method, and an automatic start detection Depending on the function and the calculation start method detected by each start detection, A /
It has a load taking-in function for sequentially taking in each load data input from the D converter 4, and a gravity center calculating function for calculating a center of gravity from each of the load data taken in sequentially.

Before calculating the center of gravity from each load data by the center of gravity calculating function, the arithmetic unit 5 performs a steady state detecting process for detecting the steady state of the subject by using a steady state detecting program described later stored in the ROM. Run.

As the display device 6, a CRT (Cathode Ra) is used.
y Tube) is used, and an analysis result obtained by analyzing the calculation result of the center of gravity by the calculation device 5 is displayed. The printing device 7 prints an analysis result obtained by analyzing the center-of-gravity calculation result by the calculation device 5, and the like.

Next, the operation of this embodiment will be described.

First, the steady state detection processing executed by the arithmetic unit 5 will be described with reference to the flowchart shown in FIG.

When the load of the subject on the detection table 2 is detected by the load sensors S1 to S3 and a load detection signal is output to the signal amplifier 3, the load is amplified to a predetermined level and A / D converted. Output to the container 4. In the A / D converter 4, each load detection signal input from the signal amplifier 3 is converted by the arithmetic unit 5.
In order to perform A / D conversion into digital data that can be processed by the, each load detection signal is converted into predetermined load data and output to the arithmetic unit 5.

In FIG. 4, load values are taken in from each load data input from the A / D converter 4 (step S1), and it is detected whether each load value is 5 kg or more (step S2). If each load value is less than 5 kg, the process returns to the load value taking process of step S1. If each load value is 5 kg or more, the load value is taken again (step S3).

Next, the center of gravity is calculated from each of the loaded load values (step S4), the center of gravity moving speed is calculated from the center of gravity calculation result, and the calculated center of gravity moving speed is stored (step S5). ). Then, it is determined whether or not one second has elapsed from the start of the processing in step S3 (step S6). That is, the process of calculating and storing the center-of-gravity moving speed at a fixed sampling cycle shown in steps S3 to S5 is repeatedly executed for one second .

If one second has elapsed, a standard deviation SD is calculated from the center-of-gravity moving speed repeatedly stored for one second (step S7), and it is determined whether or not the calculated deviation is smaller than "2" (step S7). S8). If the calculated deviation value is equal to or greater than “2”, the process returns to the load value capturing process in step S3. If the calculated deviation value is smaller than “2”, it is determined that the subject is in a steady state. Start measuring the center of gravity.

Here, the standard deviation of the center of gravity moving speed is "2".
An example of the measurement data serving as a basis for determining that the subject has entered a steady state when the value is smaller than that will be described with reference to FIG.

FIG. 5 is a graph showing the change in the distance moved by the center of gravity in a time series. “Overall” indicates the actual movement amount, and “X direction” and “Y direction” indicate the left, right, front and rear directions. 3 shows the change in distance when the movement amount is separated.

In each of the graphs of FIG. 5, it is shown that the greater the inclination, the more the change in the center of gravity. Therefore, a portion with a large inclination from 0 to 5 seconds in time indicates an unstable state immediately after the subject gets on the detection table 2, and a portion with a small inclination thereafter stands stably. Part.

Next, FIGS. 6 to 9 are graphs showing changes in some parameters obtained from the data at the time of moving the center of gravity until the subject gets on the detection table 2 and stabilizes.

FIG. 6 is a graph until the moving speed L / S of the center of gravity stabilizes. In the same manner as in FIG. This indicates an unstable state immediately after the examiner gets on the vehicle, and a portion with a small inclination thereafter can be regarded as a portion standing stably.

FIG. 7 is a graph until the effective value area of the center of gravity (effective area of the center of gravity fluctuation range) RMS is stabilized, and FIG. 8 is an area SD within 1SD of the distribution of the center of gravity. FIG. 9 is a graph showing the SD value of the center-of-gravity distribution in each direction until AREA is stabilized,
As in FIG. 5 described above, a portion where a change from 0 seconds to about 5 seconds is large indicates an unstable state immediately after the subject has got on the detection table 2 and a portion where the inclination is small thereafter. However, it can be regarded as a part standing stably.

From the above graph of each parameter, the detection table 2
It turns out that the time from the ride of the subject on the to the steady state is about 5 seconds.

Next, the "speed per sampling" graph shown in FIG. 10 is obtained by calculating the moving speed of the center of gravity for one second for each sampling period, and plotting the moving speed of the center of gravity. Looking at this graph, during the unstable period from 0 second to 5 seconds, there is a large fluctuation, and the measurement start point cannot be clearly determined.

Therefore, "SD at a speed of 1 second" shown in FIG. 11 is a graph in which the standard deviation SD of "speed at each sampling" in FIG. 10 is obtained, and this standard deviation is plotted. Looking at this graph, during the unstable period from 0 to 5 seconds, the standard deviation shows a decreasing tendency. Therefore, a certain level (in this case, 2 cm / S) is set. It is possible to form the steady state detection flow shown in FIG. 4 in which the measurement is started.

That is, the decreasing tendency of the parameters shown in FIGS. 6 to 9 and the decreasing tendency of the standard deviation shown in FIG.
As a condition until the subject riding on the detection table 2 becomes stable, when the moving speed of the center of gravity becomes smaller than “2 cm / S”, it is determined that the subject is in a steady state, and the center of gravity sway meter 1 is determined.
Measurement can be started.

As described above, when the steady state is automatically detected in the arithmetic unit 5, the measurement as the body sway meter 1 is started, and the measurement processing is executed based on the functional configuration shown in FIG. You.

That is, the arithmetic unit 5 includes the A / D converter 4
The respective loads are detected from the respective load data input from, and the center of gravity is calculated from the detected loads. At the time of calculating the center of gravity, the arithmetic unit 5 selects a start method for starting the calculation before calculating the center of gravity from each load data input from the A / D converter 4, and when the selected start method is detected, According to the calculation start method detected by the start detection, each load data input from the A / D converter 4 is sequentially taken in, and the center of gravity is calculated from each load data.

When the calculated center-of-gravity calculation result is stored, the stored center-of-gravity calculation result is analyzed, and the analysis result is displayed on the display device 6, or the analysis result is printed from the printing device 7.

As described above, in the center of gravity sway meter 1 according to the present embodiment, before starting the measurement, the subject or the rider on the detection table 2 is set on the basis of the preset steady state determination value. Detects the speed of movement of the center of gravity from the time of stabilization to the stability, automatically determines the steady state of the detector, and starts measurement. It is possible to determine the start condition of the measurement under certain conditions, obtain the objectivity of the measurement data, and obtain a quantitative Analysis can be performed.

As a result, the operability and reliability of the sway meter can be improved.

[0045] In the above embodiment, although the graph recorded in order to obtain a steady state determination value for determining a steady state in FIGS. 5 to 11, these graphs differ gender and age It is the graph plotted after performing the arithmetic processing which calculates | requires a standard deviation SD etc. from many centroid moving speed data obtained by measuring many test subjects. For this reason,
The steady state determination value set in the present embodiment (2 cm /
S) is sufficiently reliable, and the above-described steady state determination processing is sufficiently reliable.

[0046]

According to the center of gravity sway meter according to the first aspect of the present invention, as in the prior art, the measurer observes the subject on the detection table, visually confirms stability, and starts measurement. As compared with the case where the measurement is performed, the measurement start condition can be determined under a certain condition, the objectivity of the measurement data can be obtained, and the quantitative analysis can be performed. As a result, the operability and reliability of the sway meter can be improved.

According to the center of gravity sway meter according to the second aspect of the present invention, the discrimination value is obtained based on the movement data of the center of gravity obtained from many subjects of different ages and genders. The determination value for determining the stability of the center of gravity is sufficiently reliable, and the above-described steady state determination processing is sufficiently reliable.

[Brief description of the drawings]

FIG. 1 shows a center of gravity sway meter 1 according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a configuration of main parts of FIG.

FIG. 2 is a diagram showing a functional configuration of an arithmetic unit 5 in FIG. 1;

FIG. 3 is a diagram showing details of a center-of-gravity calculation function block shown in FIG. 2;

FIG. 4 is a flowchart of a steady state detection process executed by the arithmetic unit 5 of FIG. 1;

FIG. 5 is a diagram showing an example of measurement data serving as a basis for determining a steady state of a subject in the steady state detection processing of FIG. 4;

FIG. 6 is a graph showing a change in a center-of-gravity moving speed L / S among parameters obtained from data at the time of moving the center of gravity until the subject stabilizes after riding on the detection table 2;

FIG. 7 is a graph showing a change in the effective value area RMS of the center of gravity of the parameters obtained from the data at the time of moving the center of gravity until the subject stabilizes after riding on the detection table 2;

FIG. 8 shows an area SD within 1 SD of a center of gravity distribution among parameters obtained from data at the time of moving the center of gravity. AREA,
7 is a graph showing a change from when the subject gets on the detection table 2 until the subject becomes stable.

FIG. 9 is a graph showing a change in the SD value of the centroid distribution for each direction from among parameters obtained from the data at the time of moving the center of gravity until the subject stabilizes after getting on the detection table 2;

FIG. 10 is a graph in which the moving speed of the center of gravity for one second is obtained for each sampling period, and the moving speed of the center of gravity is plotted.

11 is a graph in which a standard deviation SD of the graph of FIG. 10 is obtained and the standard deviation is plotted.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 center of gravity sway meter 2 detection table 3 signal amplifier 4 A / D converter 5 arithmetic unit 6 display device 7 printing device

Claims (2)

(57) [Claims] 1. A detection stage for detecting the distribution of the load of the subject, and sequentially obtains operation means by the distribution predetermined arithmetic processing center of gravity of the subject from the load detected by the detection stage, successively obtained by the arithmetic means Analyzing means for analyzing a change in the center of gravity of the subject based on the center of gravity of the subject.
Calculates the moving speed of the subject's center of gravity every predetermined time
Speed calculating means, and a transfer of the center of gravity of the subject calculated by the speed calculating means
Standard deviation calculator that sequentially calculates the standard deviation of speed
Output means and the standard deviation calculated by the standard deviation calculation means.
To determine that it is smaller than the set discrimination value.
Discriminating means for confirming that the center of gravity of the subject has stabilized
If, Make that the center of gravity of the subject was stabilized by the determination means
If it is recognized, the center of gravity of the subject
Stabilometer meter, characterized in that it comprises an analysis control means for starting the analysis of the variation, the. 2. The center of gravity sway meter according to claim 1, wherein the discrimination value is obtained based on center-of-gravity movement data obtained from a large number of subjects of different ages and genders.