WO2009093632A1

WO2009093632A1 - Device for evaluating balance of center of gravity

Info

Publication number: WO2009093632A1
Application number: PCT/JP2009/050932
Authority: WO
Inventors: Kazuhiro Ide
Original assignee: Panasonic Electric Works Co., Ltd.
Priority date: 2008-01-23
Filing date: 2009-01-22
Publication date: 2009-07-30
Also published as: JPWO2009093632A1; CN102088902A

Abstract

Disclosed is a device for evaluating center of gravity balancing (1) wherein three or more load sensors (7) have been installed on the back surface of a platform, and a computing part (23) samples the output from each load sensor (7) at a prescribed cycle when a subject is standing on the aforementioned platform and, based on the results thereof, calculates the center of gravity balancing position and evaluates the ability (good or bad) of said subject to balance the center of gravity from the calculated position over the prescribed cycle. A balancing ability evaluating part (25) evaluates the ability to balance the center of gravity based on a value obtained by dividing total path length determined from oscillations determined from oscillations in the calculated position over a prescribed period of time by rectangular area. The value of total path length divided by rectangular area is an index indicating the magnitude of shift in the center of gravity per unit area and increases when small oscillations in the center of gravity are constantly being made, as well as within a narrow range. It tends to be high, particularly for athletes in sports wherein balancing ability is important such as ballet, gymnastics, judo, etc. Taking the ability to move into consideration, it is therefore possible to accurately evaluate the ability to balance the center of gravity.

Description

Center of gravity balance judgment device

The present invention relates to an apparatus for determining a center-of-gravity balance using a center-of-gravity fluctuation index.

Conventionally, examinations such as dizziness and balance dysfunction have been performed using the center of gravity fluctuation index. In general, there is a center-of-gravity sway meter that performs such inspection, and the conventional sway meter is described in, for example, Patent Document 1 and Patent Document 2.

In Patent Document 1, three load sensors are installed on the back surface of the platform, the center of gravity position is obtained from the output of each load sensor in a state in which a subject is mounted on the platform, and the center of gravity position that is a center of gravity swing parameter is predetermined. It is shown that the ratio of the total trajectory length over a period and the area (outer peripheral area) of the figure defined by the outermost peripheral line of the trajectory is useful for evaluating the pathological condition of the balance dysfunction.

In Patent Document 2, although there is a center of gravity shake meter, an average center of gravity position which is a center of gravity position parameter is obtained and used as original data for correction.

The ability to balance the center of gravity is influenced not only by the ability of sensory organs such as the semi-hemi organs but also by the ability of movement such as muscle strength and joint flexibility. The center-of-gravity position parameter of Patent Document 2 can be considered as an index reflecting the body bias. On the other hand, human beings are thought to maintain balance while swinging even in an upright posture, and the center-of-gravity parameters such as the total trajectory length and rectangular area of Patent Document 1 are not limited to the body bias, It can be considered as an index that reflects athletic ability. However, even if these two parameters are used individually, there is a problem in that the influence of the athletic ability is not taken into consideration and the center-of-gravity balance ability cannot be accurately determined.
Japanese Patent No. 2760471 Japanese Patent No. 2760472

An object of the present invention is to provide a center-of-gravity balance determination apparatus that can determine the center-of-gravity balance ability more accurately than the background art.

The center-of-gravity balance determination device according to one aspect of the present invention includes three or more load sensors installed on the back surface of a step and an output from each of the load sensors in a state where a subject is mounted on the step in a predetermined cycle. The ability to sample, repeatedly calculate the position of the subject's center of gravity based on the results, and balance the center of gravity of the subject from each position calculated as the center of gravity calculated within a predetermined period. A balance capability determination unit that determines a center of gravity balance capability, wherein the balance capability determination unit is a rectangle surrounded by the maximum trajectory length of the calculation position within the predetermined period by the maximum displacement in the front-rear direction and the left-right direction of the calculation position. The center-of-gravity balance ability is determined based on the value divided by the rectangular area.

The center-of-gravity balance ability is influenced not only by the ability of sensory organs such as the half organs but also by the ability of movement such as muscle strength and joint flexibility. This is because, as a result of detailed examination of the relationship between various exercises and the center of gravity balance, the inventors of the present application said that improvement of muscle strength, joint flexibility, and posture by performing appropriate exercise for a predetermined period appears in the center of gravity balance index. Based on knowledge. Here, it is considered that humans maintain balance while swinging even in an upright posture, and the total trajectory length and the center of gravity swing parameter of the rectangular area reflect not only the body bias but also the exercise ability. It can be considered as an indicator.

Among them, the total trajectory length of the calculation position within the predetermined period is the ability to move the center of gravity within the predetermined period. On the other hand, the maximum displacement within the predetermined period and the rectangular area that is a multiplication value in the front-rear direction and the left-right direction are the ability to keep the center of gravity within the range (rectangular area), compared with the outer peripheral area conventionally used Thus, effects such as front / rear and left / right body distortion and muscle imbalance appear with high sensitivity.

Then, the value obtained by dividing the total trajectory length by the rectangular area is an index that expresses the amount of movement of the center of gravity per unit area, is constantly finely swaying the center of gravity, and becomes high when performing in a narrow range, In particular, there is a tendency for athletes whose balance ability is important, such as ballet, gymnastics, and judo, to be high. Further, in order to measure the outer peripheral area, it is necessary to perform image analysis and count the number of dots, which consumes a large memory, whereas the rectangular area is the maximum in the front-rear direction and the left-right direction. It is only necessary to multiply the displacement, and it can be easily obtained.

Therefore, by determining the center of gravity balance ability from the value obtained by dividing the total trajectory length by the rectangular area, the center of gravity balance ability can be determined more accurately than in the background art, and the body distortion and exercise ability can be determined at home. ) Easy to check. In addition, it is possible to evaluate whether daily exercise training is effective in self-management of lifestyle-related diseases by using the center of gravity balance ability, and it can be used as a guideline to correct the training contents as necessary. is there.

It is a top view of the gravity center balance determination apparatus which concerns on the 1st Embodiment of this invention. It is a bottom view of the said gravity center balance determination apparatus. It is a longitudinal cross-sectional view of the said gravity center balance determination apparatus. It is an expanded sectional view of the leg part in the said gravity center balance determination apparatus. It is a figure for demonstrating the usage method of the said gravity center balance determination apparatus. It is a graph which shows an example of a gravity center fluctuation locus. It is a block diagram which shows the electric constitution of the said gravity center balance determination apparatus. It is a flowchart for demonstrating the balance capability determination operation | movement in the said gravity center balance determination apparatus. It is a graph of the gravity center fluctuation locus | trajectory for demonstrating the determination method in the said gravity center balance determination apparatus. It is a block diagram which shows the electric constitution of the gravity center balance determination apparatus which concerns on the 2nd Embodiment of this invention. It is a graph which shows the locus | trajectory length fluctuation | variation for demonstrating the 1st aspect of the method of determining the stability of the gravity center balance in the gravity center balance determination apparatus shown in the said FIG. It is a graph which shows the gravity center position fluctuation | variation of the front-back direction for demonstrating the 2nd aspect of the method of determining the stability of the gravity center balance in the gravity center balance determination apparatus shown in the said FIG. It is a graph which shows the body weight fluctuation | variation for demonstrating the 3rd aspect of the method of determining the stability of the gravity center balance in the gravity center balance determination apparatus shown in the said FIG. It is a graph of agility and endurance which shows the determination method of the athletic ability in the gravity center determination apparatus which concerns on the 3rd Embodiment of this invention. It is a top view of the gravity center balance determination apparatus which concerns on the 4th Embodiment of this invention. It is a block diagram which shows the electric constitution of the gravity center balance determination apparatus shown in FIG. It is explanatory drawing for demonstrating an example of the calculation method of a gravity center position (calculation position).

[Embodiment 1]
1 is a plan view of a center-of-gravity balance determining apparatus 1 according to a first embodiment of the present invention, FIG. 2 is a bottom view thereof, and FIG. 3 is a longitudinal sectional view thereof. The center-of-gravity balance determination apparatus 1 according to the present embodiment is provided as one function of a weight scale that measures body weight. Therefore, the external shape is similar to a conventional scale. Three or more legs (four indicated by reference numerals 8a to 8d in FIGS. 1 to 3 and collectively referred to as reference numeral 8 hereinafter) are installed on the back surface of the step 2 of the center of gravity balance determination apparatus 1. In addition, left and

right foot molds

3 a and 3 b for fitting feet are provided on the upper surface of the step platform 2.

The

foot molds

3a, 3b are provided with

depressions

4a, 4b; 5a, 5b for easy alignment of the feet. An operation panel 13 that is detachably connected via a cable wire is also embedded in the upper surface of the step 2, and the operation panel 13 is fixed in a state where the cable wire is wound around a reel. ing. An electronic circuit board 10 is built in the step platform 2. Further, a power switch 11 is provided on the front surface of the step 2 and a battery box 9 is provided on the bottom surface.

FIG. 4 is an enlarged cross-sectional view of the leg portion 8. Each of the legs 8a to 8d is formed in a cylindrical shape, and inside thereof, load receivers 6a to 6d (generally referred to as reference numeral 6) and load sensors 7a to 7d (generally referred to as follows) (Indicated by reference numeral 7) are embedded. The load receiver 6 is made of, for example, a hard metal processed into a hemispherical shape, a half crack portion thereof is fixed to the upper surface of the load sensor 7, and the apex portion is in point contact with the bottom surface of the step platform 2, from above (the step platform 2). The vertical load is transmitted to the load sensor 7 without escaping in the horizontal direction.

In the center-of-gravity balance determination apparatus 1 configured as described above, the subject turns on the power switch 11, pulls out the operation panel 13, and displays the age, sex, height, and foot length displayed on the display unit 14 such as a liquid crystal panel, for example. By inputting the basic body information, such as, from the input unit 15 in accordance with the input instruction, the balance of the center of gravity can be measured. Next, when the subject stands with his feet aligned with the

dents

4a, 4b; 5a, 5b of the step platform 2, with both hands straightened and gripping the operation panel 13, as shown in FIG. The center-of-gravity position (calculation position) is calculated within a predetermined period in which the subject holds the posture, and a center-of-gravity fluctuation locus 16 as shown in FIG. 6 is obtained.

FIG. 17 is an explanatory diagram for explaining an example of a calculation method of the gravity center position (calculation position). In FIG. 17, the distance in the X-axis direction from the origin 0 to the load sensor is m, and the distance in the Y-axis direction is L. Assume that the center of gravity of the load W of the subject is (x, y), and the

load sensors

7a, 7b, 7c, 7d detect the loads of Ma (kg), Mb (kg), Mc (kg), Md (kg), respectively. If this is the case, the X coordinate of the position where the moment in the X-axis direction balances around the origin 0, that is, the gravity center position (calculation position) is expressed by the following equation (A).
x = {m · (Mb + Md−Ma−Mc)} / W (A)

Then, the position where the moments in the Y-axis direction are balanced with respect to the origin 0, that is, the Y coordinate of the gravity center position (calculation position) is expressed by the following equation (B).
y = {L · (Ma + Mb−Mc−Md)} / W (B)
However, W = Ma + Mb + Mc + Md

Therefore, using the formulas (A) and (B), the coordinate position (x, y) of the center of gravity can be calculated from the weight value detected by the

load sensors

7a, 7b, 7c, and 7d and the distance between the sensors. .

When the coordinates of the center of gravity position (calculation position) are repeatedly calculated in this way for a predetermined period, and the obtained coordinates are sequentially connected by a line, a center-of-gravity fluctuation locus 16 as shown in FIG. 6 is obtained.

From this center-of-gravity fluctuation trajectory 16, as shown below, the total trajectory length 17 representing the amount of movement of the center-of-gravity position (calculation position) (the length of the center-of-gravity fluctuation trajectory 16), the maximum horizontal displacement (the maximum value of the X coordinate) And the maximum displacement in the front-rear direction (difference between the maximum value and the minimum value of the Y coordinate) and the rectangular area 18 that is a rectangular area surrounded by these maximum displacements, The total trajectory length 17) / (rectangular area 18) is calculated, and the quality (ability) of the center of gravity balance is determined from the (total trajectory length 17) / (rectangular area 18). Then, the display unit 14 displays, together with the weight, evaluations and scores such as low balance ability, standard, and high balance.

FIG. 7 is a block diagram showing an electrical configuration of the center-of-gravity balance determination apparatus 1 configured as described above. In each of the load sensors 7, zero point adjustment is appropriately performed. A signal indicating the weight detected by each load sensor 7 is appropriately amplified by an amplifier (not shown) or the like, and then AD-converted by the AD converter 21 at a predetermined sampling period. Data indicating the detected weight is stored in an area including the RAM of the storage unit 22. On the other hand, the basic body information of the subject input from the input unit 15 is stored (registered) in a non-volatile area of the storage unit 22.

The calculation unit 23 includes, for example, a CPU (Central Processing Unit) that executes predetermined calculation processing, a ROM (Read Only Memory) that stores a predetermined control program, and a RAM (Random Access Memory) that temporarily stores data. And its peripheral circuits and the like. And the calculating part 23 functions as the weight measurement part 24 (weight calculating part) and the balance ability determination part 25 by running the control program memorize | stored in ROM, for example.

The weight measurement unit 24 reads the detection results of the load sensors 7a to 7d for each sampling cycle from the storage unit 22, obtains the fluctuation of the total value of the detection values for each sampling, and the fluctuation is within a predetermined value set in advance. The total value when it falls within the range is determined as the weight.

On the other hand, the balance ability determination unit 25 obtains the center-of-gravity position coordinates for each sampling based on the distance between the load sensors 7. Note that the coordinates obtained here are not strictly the center of gravity position but the foot pressure center COP (Center of Position), but in the static state, it can be considered that the center of gravity position and the foot pressure center are almost the same. It is written as the center of gravity. The balance ability determination unit 25 further calculates from the position of the center of gravity to obtain (total trajectory length 17) / (rectangular area 18), determines the balance ability, and causes the display unit 14 to display the balance ability.

Specifically, for example, a first threshold value α and a second threshold value β having a relationship of α> β are set in advance, and the balance ability determination unit 25 determines (total trajectory length 17) / (rectangular area 18). If the value exceeds the first threshold value α, it is determined that the balance ability is high. If the value is less than the first threshold value α and greater than or equal to the second threshold value β, the balance ability is determined to be standard, and the second threshold value β is not satisfied. It may be determined that the balance ability is low.

Thereby, the balance ability determination unit 25 determines that the center of gravity balance ability of the subject is higher as the value of (total trajectory length 17) / (rectangular area 18) is larger.

For example, a person (for example, a dancer) who is considered to have a high center-of-gravity balance ability and a person who is considered to have a standard center-of-gravity balance ability (for example, a company employee of 20 to 40 years old) experimentally (total trajectory length 17 ) / (Rectangular area 18) is calculated, and the value of (total trajectory length 17) / (rectangular area 18) and the center of gravity balance ability of a person who is considered to have high center of gravity balance ability are considered to be standard. A central value between the value of (total trajectory length 17) / (rectangular area 18) of the person can be used as the first threshold value α.

Also, for example, a person who is considered to have a standard center of gravity balance ability and a person who is considered to have a low center of gravity balance ability (for example, an elderly person 65 years or older) (total trajectory length 17) / (rectangle The value of (Area 18) is calculated, and the value of (total trajectory length 17) / (rectangular area 18) of a person whose center of gravity balance ability is considered to be standard and the person who is considered to have a low center of gravity balance ability (total trajectory length) The central value between 17) / (rectangular area 18) can be used as the second threshold value β.

FIG. 8 is a flowchart for explaining the determination operation of the balance ability described above. The subject first turns on the power in step S1, and inputs age, gender, height, and foot length in step S2. In step S3, immediately after the subject is placed on the platform 2 (from the time when the output of the load sensor 7 adjusted to the zero point fluctuates), the sampling of the output of each load sensor 7 is set at a predetermined cycle set in advance. In step S4, the weight measurement unit 24 determines the weight based on the total value of the obtained detection results of the load sensors 7, and the result is displayed on the display unit 14.

In step S5, the center-of-gravity position coordinates are sequentially calculated from the detection results of the load sensors 7 in step S3, and the center-of-gravity position coordinates over a predetermined period after the start of measurement are extracted. In step S6, the balance ability level is determined by calculating (total trajectory length 17) / (rectangular area 18) using the barycentric position coordinates, and the result is displayed in step S7.

Here, the reason for using (total trajectory length 17) / (rectangular area 18) to determine the balance ability level is as follows. First, the total trajectory length 17 is the ability to move the center of gravity in unit time. Further, the maximum displacement in the front-rear direction and the left-right direction and the rectangular area 18 which is a multiplication value thereof are the ability to keep the center of gravity within the range, and the front-rear direction and the left-right direction compared to the conventionally used outer peripheral area. Effects such as body distortion and muscle imbalance appear with high sensitivity. It is thought that humans maintain balance while constantly shaking even in an upright posture, and the total trajectory length and rectangular area do not become zero.

Then, the value obtained by dividing the total trajectory length 17 of the calculation position within such a predetermined period by the rectangular area 18 surrounded by the maximum displacement in the front-rear direction and the left-right direction of the calculation position is the center-of-gravity movement amount per unit area. It is an index to show, and it becomes high when the center of gravity is constantly swaying and it is performed in a narrow range. For this reason, it is necessary to smoothly perform quick and accurate movement and stillness, and in particular, there is a tendency to be high in athletes whose balance ability is important, such as ballet, gymnastics, and judo.

Specifically, the basic concept differs between the outer peripheral area according to the background art and the rectangular area according to the present invention. For example, in the center of gravity fluctuation locus shown in FIG. 9, the outer

peripheral areas

27 and 28 in the two states of FIGS. 9A and 9B are Although the same, the rectangular area 29 in FIG. 9A is smaller than the rectangular area 30 in FIG. 9B. This is because body distortion in the front-rear and left-right directions and imbalance in muscle strength affect the sway of the center of gravity. For the sake of simplicity, assuming that the

total trajectory lengths

31 and 32 are exactly the same, the index that has been widely used in the past obtained by dividing the

total trajectory lengths

31 and 32 by the outer

peripheral areas

27 and 28 has the same value in the two states. . On the other hand, in the index of the present embodiment obtained by dividing the

total trajectory lengths

31 and 32 by the

rectangular areas

29 and 30, it is determined that the balance ability is higher in FIG. 9A than in FIG. 9B. Since the rectangular area 29 in FIG. 9A is smaller than the rectangular area 30 in FIG. 9B, the center of gravity movement is controlled within a narrower range in FIG. 9A, and the balance ability is comprehensive. This is because it can be judged to be expensive.

Actually, the total trajectory length 17 and the rectangular area 18 are stored in advance as a table in the ROM area or the like of the storage unit 22 so as to indicate how many points in each range, or (total trajectory length 17) / A table in which (rectangular area 18) is in a range from how many to what is stored is stored, and the balance capacity determination unit 25 calculates the storage unit 22 from the obtained total trajectory length 17 and rectangular area 18. , Or after obtaining the ratio, the table is referred to, and the obtained score is displayed on the display unit 14 as the score of the overall balance ability level.

For example, such a table has a total trajectory length of 17 and a rectangular shape experimentally for a person considered to have a high balance ability, a person considered to have a standard balance ability, and a person considered to have a low balance ability. The area 18 is obtained and scored based on the statistical data distribution.

As described above, in the center-of-gravity balance determination apparatus 1 according to the present embodiment, three or more load sensors 7 are installed on the back surface of the platform 2, and the calculation unit 23 is in a state in which a subject is mounted on the platform 2. The output from each of the load sensors 7 is sampled at a predetermined cycle, and the center-of-gravity balance position is calculated based on the result, and the center-of-gravity balance ability (the center-of-gravity balance quality) is determined from the calculated position over a predetermined period. In doing so, the balance capacity determination unit 25 divides the total trajectory length 17 of the calculation position within the predetermined period by the rectangular area 18 surrounded by the maximum displacement in the front-rear direction and the left-right direction of the calculation position, The center of gravity balance ability is determined.

Here, the center-of-gravity balance ability is influenced not only by the ability of sensory organs such as the semi-hemi organ, but also by the ability of movement such as muscle strength and joint flexibility. This is because, as a result of detailed examination of the relationship between various exercises and the center of gravity balance, the inventors of the present application said that improvement of muscle strength, joint flexibility, and posture by performing appropriate exercise for a predetermined period appears in the center of gravity balance index. Based on knowledge. The (total trajectory length 17) / (rectangular area 18) can be considered as an index reflecting not only the body bias but also the athletic ability.

Therefore, by determining the center-of-gravity balance ability from (total trajectory length 17) / (rectangular area 18), it is possible to accurately determine the center-of-gravity balance ability, and to easily check body distortion and exercise ability. . By the way, even in healthy individuals, in recent years, it has been considered that weakness of the legs and hips due to lifestyle-related diseases and lack of exercise has affected the stability of the balance of the center of gravity. The stability of the balance of the center of gravity is related to the strength of the abdominal muscles, back muscles, puffer muscles in the lower limbs, soleus muscles, the flexibility of the hip joints, knee joints, and ankle joints. The posture (alignment) is also involved in the balance of the center of gravity. When the body is distorted, the stability of the center of gravity balance is reduced.

However, until now, measurement of muscle strength, flexibility, posture, etc. has been performed using dedicated equipment and diagnostic imaging. For this reason, it was difficult to simply measure at home. However, by using the center-of-gravity balance determination apparatus 1 according to the present embodiment, it is possible to easily check body distortion and exercise ability at home. Moreover, in the self-management of the lifestyle-related diseases, it is possible to evaluate whether or not daily exercise training is effective using the center of gravity balance ability, and it can be used as a guideline for correcting the training content as necessary. Useful.

In order to measure the outer peripheral area used in the past, the outer peripheral line of the movement locus of the center of gravity is drawn with an image, image analysis is performed, and the number of dots in the image of the area surrounded by the outer peripheral line is counted. The rectangular area can be calculated simply by multiplying the maximum displacement in the front-rear direction and the left-right direction, whereas it requires a large memory and is easily obtained.

[Embodiment 2]
FIG. 10 is a block diagram showing an electrical configuration of the center-of-gravity balance determination apparatus 41 according to the second embodiment of the present invention. The center-of-gravity balance determination device 41 is similar to the above-described center-of-gravity balance determination device 1, and corresponding portions are denoted by the same reference numerals, and description thereof is omitted. It should be noted that in the center-of-gravity balance determination device 41, the calculation unit 43 is provided with a center-of-gravity balance stable state determination unit 46, and the center-of-gravity balance stable state determination unit 46 determines that the center-of-gravity balance is stable. Thus, a trigger for starting measurement is given to the weight measuring unit 24, and a trigger for starting calculation of the center of gravity balance position is given to the balance ability determining unit 45.

In this regard, in the conventional center-of-gravity sway meter, it was not clearly defined at which point the measurement started after the subject took a standing posture. For this reason, the measurement period is ambiguously determined by the subjectivity of the measurer and takes 30 to 60 seconds. On the other hand, in this embodiment, the determination period of the center of gravity balance can be automatically set and evaluated in a short time, and the determination can be performed with good reproducibility and accuracy.

Specifically, first, in the first aspect, the center-of-gravity balance stable state determination unit 46 starts a counting operation from the time when the subject puts his / her foot on the step platform 2, and when the predetermined time is counted, the center of gravity is counted. It is determined that the balance is in a stable state. FIG. 11 is a graph showing the change in the trajectory length for 50 msec over 10 seconds after obtaining the trajectory length every 50 msec immediately after the subject puts his foot on the platform 2. In FIG. 11, it is understood that the trajectory length is almost stable in about 5 seconds immediately after the subject puts his / her foot on the platform 2.

For this reason, the center-of-gravity balance stable state determination unit 46 determines that the center of gravity has reached a stable state when a predetermined time, for example, about 5 seconds has passed since immediately after placing the foot, and determines this time. A trigger is given as the calculation start time t0, and (total trajectory length 17) / (rectangular area 18) up to a predetermined time, for example, up to 10 seconds, is obtained by the balance ability determination unit 45, and the center-of-gravity balance ability To determine. Thereby, reproducibility is improved even in repeated measurement, and the center-of-gravity balance ability can be determined more accurately.

Next, in the second aspect, the center-of-gravity balance stable state determination unit 46 converges within a predetermined range in which the center-of-gravity movement distance per unit time from the time when the subject places his / her foot on the platform 2. It is determined that the center-of-gravity balance is in a stable state at a point in time when the above state continues for a predetermined number of times set in advance. FIG. 12 is a graph showing the change in the center of gravity position in the front-rear direction for 10 seconds immediately after the subject puts his / her foot on the platform 2. As shown in FIG. 12, the position of the center of gravity is not determined for a while from immediately after the subject puts his / her foot on the platform 2, and falls within a certain range as time passes.

The center-of-gravity balance stable state determination unit 46 determines that, for each unit time, for example, the amount of difference from the one-sampling of the center-of-gravity position obtained at a preset predetermined sampling cycle is within a preset predetermined range. It is determined that the position of the center of gravity is in a stable state when it has converged continuously for a predetermined number of times set in advance, and a trigger is given with this time as the calculation start time t0. Then, (total trajectory length 17) / (rectangular area 18) for a predetermined time set in advance, for example, up to 10 seconds, is obtained by the balance ability judging unit 45, and the center of gravity balance ability is judged. Even in this case, reproducibility is improved even in repeated measurement, and the center-of-gravity balance ability can be determined more accurately.

Similarly, in the third aspect, the center-of-gravity balance stable state determination unit 46 converges the change in weight per unit time within a predetermined range from the time when the subject puts his / her foot on the platform 2. When the state continues for a predetermined number of times set in advance, it is determined that the balance of the center of gravity is in a stable state. FIG. 13 is a graph showing the body weight fluctuation for 10 seconds immediately after the subject puts his / her foot on the platform 2. As shown in FIG. 13, immediately after the subject puts his / her foot on the platform 2, the total load value, that is, the weight is obtained, and the fluctuation is continuously performed a predetermined number of times within a predetermined level. When it is included, it is determined that the balance of the center of gravity is stable, and this time is set as a calculation start time t0. Even in this case, reproducibility is improved even in repeated measurement, and the center-of-gravity balance ability can be determined more accurately.

[Embodiment 3]
FIG. 14 is a diagram for explaining a determination method in the center-of-gravity balance determination apparatus according to the third embodiment of the present invention. The center-of-gravity balance determination apparatus according to the present embodiment can also use the configuration of the center-of-gravity balance determination apparatus 1 described above. It should be noted that the balance ability determination unit 25 of the calculation unit 23 exercises from the center of gravity balance ability. The ability level is determined. Here, the exercise ability is, for example, agility and endurance.

Agility is thought to be an ability related to the speed of adjusting muscle contraction and relaxation. That is, the high agility means that the speed for adjusting the contraction and relaxation of muscles is fast, and the high adjustment speed means that the speed for adjusting the balance of the center of gravity of the body is fast. Therefore, it means that the higher the agility, the center of gravity can be adjusted with a small shaking motion within a small area, and the total trajectory length / rectangular area becomes large.

Therefore, the balance ability determination unit 25 determines that the greater the (total trajectory length 17) / (rectangular area 18), the better the subject's agility and the higher the agility level.

Endurance is thought to be the ability to maintain muscle contraction and relaxation, but the center of gravity balance ability is the change in stability after the sway of the center of gravity, that is, the change in (total trajectory length 17) / (rectangular area 18). Can be used to represent endurance level. That is, after the fluctuation of the center of gravity is stabilized, if the variation with time of (total trajectory length 17) / (rectangular area 18) is small and an almost constant value is maintained, the endurance is considered high. If the value of the trajectory length 17) / (rectangular area 18) varies greatly with time, the endurance is considered low.

Therefore, the balance ability determination unit 25 determines that the endurance is higher and the endurance level is higher as the variation with time of (total trajectory length 17) / (rectangular area 18) after the center of gravity is stabilized is smaller. To do.

FIG. 14 shows the results of the present inventor performing a balance evaluation on 28 monitors and showing the agility level on the horizontal axis and the endurance level on the vertical axis. Here, the agility level is a value of (total trajectory length 17) / (rectangular area 18) by dividing the value of (total trajectory length 17) / (rectangular area 18) for 5 seconds after the center of gravity is stabilized into 10 levels. A score of 0 to 10 is assigned so that the larger the value is, the higher the score is (high agility).

Further, the endurance level is calculated by continuously calculating (total trajectory length 17) / (rectangular area 18) for 1 second after stabilization five times, and dividing the coefficient of variation by dividing the standard deviation by the average value into 10 stages, A score of 0 to 10 is assigned so that the smaller the coefficient of variation, the higher the score (the higher the endurance).

According to the present embodiment, it is possible to classify the subject's motor ability characteristics into four types based on the agility and endurance levels as shown in FIG.

In this way, in addition to the center of gravity balance level, it is also possible to determine athletic ability levels such as agility and endurance.

[Embodiment 4]
FIG. 15 is a plan view of a center-of-gravity balance determination device 51 according to the fourth embodiment of the present invention, and FIG. 16 is a block diagram showing its electrical configuration. The center-of-gravity balance determination device 51 is similar to the center-of-gravity balance determination device 1 described above, and corresponding portions are denoted by the same reference numerals and description thereof is omitted. It should be noted that in this embodiment, in the

foot molds

53a and 53b on the step platform 2, the

depressions

54a and 54b serve as current application electrodes as input electrodes, and the grip portions 64a on both the left and right sides of the operation panel 63. , 64b are voltage measuring electrodes that are output electrodes, and a voltage between the

voltage measuring electrodes

64a, 64b is measured to a current source 55 that sends current from the current applying

electrodes

54a, 54b to the subject's body. A voltage detection unit 65 is provided, and the calculation unit 73 is further provided with a body composition component calculation unit 66 in addition to the weight measurement unit 24 and the balance ability determination unit 25.

The body composition component calculation unit 66 measures body impedance from the voltage between the

voltage measurement electrodes

64a and 64b and the current passed from the current source 55, and the age and sex input in advance from the operation panel 63 as the body impedance. Using body basic information such as height, body composition components such as body fat percentage, lean mass and muscle mass are calculated and displayed on the display unit 14.

The method of using the center-of-gravity balance determination device 51 is the same as in FIG. 5 described above, and the subject turns on the power switch 11, removes the operation panel 63 from the step 2, and pulls out the cable wire 60. Subsequently, according to an input instruction of basic body information such as age, gender, height, and foot length displayed on the display unit 14, the information is input from the input unit 15 to measure the balance of the center of gravity and body composition. Is possible. Next, when both feet stand in the

depressions

54a, 54b; 5a, 5b of the step platform 2, both hands are straightened and the operation panel 63 is gripped as shown in FIG. At the same time as the center of gravity (calculation position) is determined within a predetermined period of time in which the posture is maintained, an alternating current is generated from the current source 55 of the electronic circuit board 10 at a predetermined frequency. A weak current is applied to the body from the sole of the subject via the

current application electrodes

54a and 54b. The voltage generated by the weak current is detected by the voltage detection unit 65 from the

voltage measurement electrodes

64 a and 64 b provided on the operation panel 63 and is input to the body composition component calculation unit 66.

With this configuration, the body composition can be measured simultaneously with the weight and center of gravity balance ability, and the health condition can be known in more detail.

As described above, the calculation start timing for obtaining the center-of-gravity balance ability is the time when the center-of-gravity sway becomes stable, but it may be started in a transient state immediately after the subject puts his foot on the stepping platform 2 until it reaches the stable state. Further, when determining the center-of-gravity balance ability from (total trajectory length 17) / (rectangular area 18), it may be determined using a correction table based on basic body information such as age, sex, and height. Furthermore, (total trajectory length 17) / (rectangular area 18) is used as an index representing the athletic ability level. However, the total trajectory length 17 and the rectangular area 18 themselves may be combined, and In addition to the agility and endurance, it may be further classified.

That is, the center-of-gravity balance determination device according to one aspect of the present invention predetermines outputs from the three or more load sensors installed on the back surface of the step and the load sensors in a state where the subject is mounted on the step. Ability to sample at periodic intervals, repeatedly calculate the position of the subject's center of gravity based on the result, and balance the center of gravity of the subject from each position calculated as the center of gravity calculated within a predetermined period A balance ability determination unit that determines the center-of-gravity balance ability, and the balance ability determination unit surrounds the total trajectory length of the calculation position within the predetermined period by the maximum displacement in the front-rear direction and the left-right direction of the calculation position. The center-of-gravity balance ability is determined based on the value divided by the rectangular area to be measured.

According to said structure, three or more load sensors are installed in the back surface of a step, and the balance capability determination part is a period which presets the output from each said load sensor in the state which mounts the test subject on the said step. Sampling is performed, and the position of the center of gravity is calculated based on the result, and the center-of-gravity balance ability (the center-of-gravity balance quality) of the subject is determined from the calculated position over a predetermined period. At this time, the balance ability determination unit, based on a value obtained by dividing the total trajectory length of the calculation position within the predetermined period by a rectangular area surrounded by the maximum displacement in the front-rear direction and the left-right direction of the calculation position, Determine ability.

Further, it is preferable that the balance ability determination unit determines that the subject's center of gravity balance ability is higher as the value obtained by dividing the total trajectory length by the rectangular area is larger.

The value obtained by dividing the total trajectory length by the rectangular area, as described above, is constantly increasing in the small center of gravity, and increases when it is performed in a narrow range, so the value obtained by dividing the total trajectory length by the rectangular area It can be determined that the larger the is, the higher the center of gravity balance ability of the subject is.

Further, it is further provided with a center of gravity balance stable state determination unit that determines whether or not the center of gravity balance is stable from the output of each load sensor and causes the balance ability determination unit to calculate the center of gravity position when the balance is stable. Is preferred.

According to the above configuration, the center-of-gravity balance stable state determination unit is further provided, and the center-of-gravity balance stable state determination unit gives a trigger for calculating the center-of-gravity position to the balance ability determination unit when the center-of-gravity balance is stabilized.

Therefore, the center-of-gravity balance determination period can be automatically set, and a period in which the balance is temporarily unstable immediately after the subject puts his / her foot on the platform is excluded from the center-of-gravity balance determination period. As a result, the accuracy of determining the center of gravity balance ability can be improved.

Furthermore, it is preferable that the center-of-gravity balance stable state determination unit determines that the center-of-gravity balance is in a stable state when a predetermined time has elapsed since the subject placed his / her foot on the platform.

According to the above configuration, the elapsed time starts counting from the time when the subject puts his / her foot on the platform, and when the predetermined time is counted, it is determined that the balance of the center of gravity is in a stable state. Can be easily determined.

In addition, the center-of-gravity balance stable state determination unit is configured to perform a predetermined number of times after the subject puts his or her foot on the platform, a state in which a change in the center-of-gravity movement distance or weight per unit time converges within a predetermined range. It is preferable to determine that the balance of the center of gravity is in a stable state.

According to the above configuration, as a result of excluding the period in which the balance is temporarily unstable immediately after the subject puts his / her foot on the platform, the determination accuracy of the center of gravity balance is improved. can do.

Furthermore, it is preferable that the balance ability determination unit determines an exercise ability level using the total trajectory length and the rectangular area.

According to the above configuration, the level of athletic ability can be determined in addition to the level of the center of gravity balance ability.

The athletic ability level represents agility, and the balance ability determination unit further increases the agility of the subject as the value obtained by dividing the total trajectory length by the rectangular area is larger. Is preferably determined.

According to this configuration, the higher the agility, the more the center of gravity can be adjusted with a small shaking movement within a small area, and the value obtained by dividing the total trajectory length by the rectangular area becomes larger. It can be determined that the greater the value divided by the rectangular area, the better the agility of the subject.

The athletic ability level represents endurance, and the balance ability determination unit further determines the endurance as the fluctuation with time of the value obtained by dividing the total trajectory length by the rectangular area decreases. May be determined to be high.

According to this configuration, since the variation with time of the value obtained by dividing the total trajectory length by the rectangular area is small and a substantially constant value is maintained, it is considered that the endurance is high. It can be determined that the endurance is higher as the variation with time of the value obtained by dividing the total trajectory length by the rectangular area is smaller.

Further, according to a weight calculation unit that obtains the weight of the subject from the sum of outputs of the load sensors, an input electrode and an output electrode, a current source that sends current from the input electrode to the subject's body, and a flow of the current It is preferable to further include a body composition component calculation unit that measures body impedance from the voltage between the output electrodes and calculates a body composition component from the body impedance.

According to the above configuration, it is possible to simultaneously measure the weight and body composition as well as the determination of the balance of the center of gravity with a single device.

Further, the number of load sensors is four, and the balance ability determination unit is configured such that the distance in the X-axis direction from the origin to each load sensor in the X and Y coordinate systems is m, the distance in the Y-axis direction is L, and each load sensor is , The coordinates (x, y) of the calculation position are preferably calculated by the following equations (A) and (B).

x = {m · (Mb + Md−Ma−Mc)} / W (A)
y = {L · (Ma + Mb−Mc−Md)} / W (B)
However, W = Ma + Mb + Mc + Md
According to this configuration, the balance capacity determination unit uses the distance in the X-axis direction from the origin to each load sensor in the X and Y coordinate systems, the distance in the Y-axis direction, and the weight value detected by each load sensor. The coordinates of the calculation position can be calculated.

Claims

3 or more load sensors installed on the back of the platform,
The output from each of the load sensors in the state where the subject is mounted on the platform is sampled at a predetermined cycle, and the calculation position that is the center of gravity of the subject is repeatedly calculated based on the result, and the calculation is performed within a predetermined period. A balance ability determination unit that determines a center of gravity balance ability that is an ability to balance the center of gravity of the subject from each calculated position that is the center of gravity position,
The balance ability determination unit is configured to calculate the balance of the center of gravity based on a value obtained by dividing the total trajectory length of the calculation position within the predetermined period by a rectangular area surrounded by a maximum displacement in the front-rear direction and the left-right direction of the calculation position. A center-of-gravity balance determination device characterized by determining ability.
The balance ability determination unit
The center-of-gravity balance determination device according to claim 1, wherein the center-of-gravity balance determination apparatus determines that the subject's center-of-gravity balance ability is higher as the value obtained by dividing the total trajectory length by the rectangular area is greater.
It is further determined whether or not the center of gravity balance is stable from the output of each load sensor, and when the balance is stable, the balance ability determination unit further includes a center of gravity balance stable state determination unit that calculates the center of gravity position. The center-of-gravity balance determination apparatus according to claim 1 or 2.
The center-of-gravity balance stable state determination unit
The center-of-gravity balance determination apparatus according to claim 3, wherein the center-of-gravity balance is determined to be in a stable state when a predetermined time has elapsed since the subject placed his / her foot on the platform.
The center-of-gravity balance stable state determination unit
It is determined that the balance of the center of gravity is stable when a state in which the change in the center-of-gravity movement distance or body weight converges within a predetermined range from the time when the subject puts his / her foot on the stepping platform continues for a predetermined number of times. The center-of-gravity balance determination apparatus according to claim 3.
The balance ability determination unit
The center-of-gravity balance determination apparatus according to any one of claims 1 to 5, wherein an athletic ability level is determined using the total trajectory length and the rectangular area.
The athletic ability level represents agility,
The balance ability determination unit further includes:
The center-of-gravity balance determination device according to claim 6, wherein the larger the value obtained by dividing the total trajectory length by the rectangular area, the better the subject's agility.
The athletic ability level represents endurance,
The balance ability determination unit further includes:
The center-of-gravity balance determination device according to claim 6, wherein the endurance is determined to be higher as the change with time of the value obtained by dividing the total trajectory length by the rectangular area is smaller.
A weight calculator that calculates the weight of the subject from the sum of the outputs of the load sensors;
Input and output electrodes;
A current source for passing a current from the input electrode to the body of the subject;
9. A body composition component calculation unit that measures body impedance from a voltage between the output electrodes due to the current flow and calculates a body composition component from the body impedance. The center-of-gravity balance determination apparatus according to claim 1.
There are four load sensors,
The balance ability determination unit
If the distance in the X-axis direction from the origin to each load sensor in the X, Y coordinate system is m, the distance in the Y-axis direction is L, and each load sensor detects a load of Ma, Mb, Mc, Md, respectively, Calculate the coordinates (x, y) of the calculation position by the following formulas (A) and (B): x = {m · (Mb + Md−Ma−Mc)} / W (A)
y = {L · (Ma + Mb−Mc−Md)} / W (B)
However, W = Ma + Mb + Mc + Md
The center-of-gravity balance determination device according to any one of claims 1 to 9, wherein: