JP2008246179A - Activity meter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an activity meter capable of calculating the accurate amount of activity. <P>SOLUTION: The activity meter includes: an acceleration detection means 1 to be mounted on a human body for detecting the acceleration in three axes orthogonal to each other; an action scene judgement means 2 for judging which one of "life activity", "walking" and "running" the action scene of a person is on the basis of the acceleration obtained by the acceleration detection means 1; an activity amount calculation means 3 provided with operation expressions to be used when calculating the amount of the activity from the acceleration for the respective action scenes, for selecting the operational expression to be used on the basis of the judged result of the action scene judgement means 2 and calculating the amount of the activity; a display means 4 for displaying the amount of the activity calculated in the activity amount calculation means 3 or the like; and a storage means 5 storing various data such as the acceleration obtained by the acceleration detection means 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an activity meter that measures (calculates) an activity amount of a person.

  2. Description of the Related Art Conventionally, an activity meter has been proposed that includes an acceleration sensor that is mounted on a human body and detects three-axis accelerations orthogonal to each other, and an arithmetic processing unit that calculates an activity amount based on the acceleration obtained by the acceleration sensor. (For example, refer to Patent Document 1).

The active mass meter as shown in Patent Document 1 is composed of “METs” values, which are used in the American Sports Medicine Association, and indicate how many times the energy consumption during exercise is greater than the energy consumption during rest. It is configured to calculate exercise intensity as an activity amount, and when calculating the activity amount, an arithmetic expression indicating the correlation between the fluctuation average (variance) of acceleration obtained by the acceleration sensor and the activity amount (that is, The conversion formula that converts the fluctuation average of acceleration into exercise intensity) is used.
JP 2006-204446 A

  By the way, when the person is walking and running, the result is that the amount of activity is different even if the acceleration obtained by the acceleration sensor is the same. That is, the amount of human activity varies depending on the action scene (exercise state).

  On the other hand, the activity meter as shown in Patent Document 1 uses one arithmetic expression indicating the correlation between the fluctuation average of acceleration and the activity amount, and the activity amount indicates what kind of behavior the person has. Since the amount of activity in the scene is not taken into consideration, the approximate amount of activity could be calculated, but it was insufficient in terms of calculating the exact amount of activity.

  The present invention has been made in view of the above points, and an object thereof is to provide an activity meter capable of calculating an accurate activity amount.

  In order to solve the above-mentioned problem, in the invention of claim 1, an acceleration detection unit that is mounted on a human body and detects acceleration, and an action scene that determines a human action scene based on the acceleration obtained by the acceleration detection unit It comprises a determining means and an activity amount calculating means for calculating an activity amount from the acceleration obtained by the acceleration detecting means based on the determination result by the action scene determining means.

  According to the first aspect of the present invention, since the amount of activity is calculated according to the action scene determined based on the acceleration obtained by the acceleration detecting means, the difference in the person's action scene can be reflected in the amount of activity, and accurate The amount of activity can be calculated.

  The invention of claim 2 is characterized in that, in the invention of claim 1, the action scene determination means is configured to determine whether the action scene is a daily activity, walking, or running.

  According to the invention of claim 2, since the difference in the amount of activity in each of daily activities, walking, and running can be reflected, an accurate amount of activity can be calculated.

  The invention of claim 3 is characterized in that, in the invention of claim 1 or 2, the action scene determination means is configured to determine the action scene based on the magnitude of acceleration obtained by the acceleration detection means. .

  According to the invention of claim 3, since the amount of activity is calculated according to the action scene determined based on the magnitude of the acceleration obtained by the acceleration detecting means, the difference in human action scene can be reflected in the amount of activity. The amount of activity can be calculated accurately.

  In the invention of claim 4, in the invention of any one of claims 1 to 3, the action scene determination means calculates the number of steps per unit time from the acceleration obtained by the acceleration detection means, and the person is determined based on the number of steps. The action scene is determined to be determined.

  According to the invention of claim 4, the amount of activity is calculated according to the action scene determined based on the number of steps per unit time calculated based on the acceleration obtained by the acceleration detecting means. The difference can be reflected in the amount of activity and the amount of activity can be calculated accurately.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects of the present invention, the activity amount calculating means has an arithmetic expression used for calculating the activity amount from the acceleration for each action scene, An arithmetic expression to be used is selected based on the determination result of the scene determination means.

  According to the fifth aspect of the present invention, the amount of activity can be calculated more accurately than when the amount of activity is calculated using only one arithmetic expression.

  The present invention has an effect that a difference in human behavior scene can be reflected in an activity amount, and an accurate activity amount can be calculated.

(Embodiment 1)
As shown in FIG. 1, the activity meter according to the present embodiment includes an acceleration detection means 1 that is mounted on a human body and detects three-axis accelerations that are orthogonal to each other, and a human being based on the acceleration obtained by the acceleration detection means 1. Action scene determination means 2 for determining the action scene, activity amount calculation means 3 for calculating an activity amount from the acceleration obtained by the acceleration detection means 1 based on the determination result by the action scene determination means 2, and activity amount calculation means Display means 4 for displaying the amount of activity calculated in 3, storage means 5 comprising a storage device such as RAM or HDD in which various data such as acceleration obtained by the acceleration detection means 1 are stored, and an activity meter Operating means (not shown) for performing an on / off operation, power supply means (not shown) such as a battery for driving the activity meter, and a housing (not shown) for storing them. Yes. In addition, the said housing | casing consists of resin molded products etc., for example, and is formed in the magnitude | size which a person can carry.

  The acceleration detecting means 1 is, for example, a three-axis acceleration sensor (not shown) that outputs each of three-axis accelerations perpendicular to each other in an analog format, and samples the output of the three-axis acceleration sensor at a predetermined period in a digital format. And an acceleration detection circuit (not shown) for converting into an output.

  As the three-axis acceleration sensor, for example, an acceleration sensor using a microelectromechanical system (MEMS) having a small size and low power consumption is used. As the acceleration sensor, a piezoresistive acceleration sensor, a capacitance acceleration sensor, or the like can be used. As the triaxial acceleration sensor, a sensor that can output a triaxial acceleration value by combining a biaxial acceleration sensor and a monoaxial acceleration sensor may be used. It is also possible to use one that can output a three-axis acceleration value. Note that a digital output sensor may be used as the three-axis acceleration sensor. In this case, an acceleration detection circuit that performs A / D conversion can be omitted.

  The action scene determination unit 2 is a predetermined time of a norm (that is, a combined acceleration) in which the magnitude of the acceleration obtained by the acceleration detection unit 1, in this embodiment, the acceleration of each axis obtained by the acceleration detection unit 1 is a vector component. The action scene is determined based on the fluctuation average (standard deviation).

  For example, as shown in FIG. 2, the action scene determination unit 2 determines that an action scene is a low-intensity action that does not involve walking if the above-mentioned variation average is less than a first threshold value (0.3 G in the present embodiment). If it is determined that there is a certain “living activity” and the variation average is equal to or greater than a second threshold (0.6 G in the present embodiment) that is greater than the first threshold, the action scene is determined to be “running”, and the variation average is If it is equal to or more than the first threshold value and less than the second threshold value, the action scene is determined as “walking”. Such a determination result is output to the activity amount calculation means 3.

  Here, the first threshold value is a value that becomes a boundary between “life activity” and “walking”. For example, the above-mentioned variation average when the human action scene switches from “life activity” to “walk” Can be obtained from statistical data. Similarly, the second threshold value is a value that serves as a boundary between “walking” and “running”. For example, the statistics of the above-mentioned variation average when a human action scene is switched from “walking” to “running”. It can be obtained from data. Moreover, the value of each threshold value in this embodiment is an example to the last, and it is not the meaning limited to this numerical value. This also applies to Embodiments 2 and 3 described later.

  When the activity amount calculation means 3 receives the determination result of the action scene determination means 2, the magnitude of the acceleration obtained by the acceleration detection means 1 (acceleration of each axis obtained by the acceleration detection means 1 in this embodiment) The amount of activity is calculated using a norm with a vector component as a vector component), and an arithmetic expression based on the determination result of the action scene determination unit 2 is used to calculate the amount of activity. It is configured.

  That is, the activity amount calculating means 3 has an arithmetic expression used when calculating the activity amount from the acceleration (that is, a conversion expression used when converting the acceleration into the activity amount) for each action scene, and the action scene determination Based on the determination result of the means 2, an arithmetic expression to be used for calculating the amount of activity is selected. For example, when the action scene is determined to be “life activity” by the action scene determination means 2, an arithmetic expression for life activity is used, and when it is determined to be “walking”, an arithmetic expression for walking is used. If it is determined that the vehicle is “running”, a driving formula is used. The arithmetic expressions corresponding to these behavioral scenes show the correlation between the above-mentioned fluctuation average and the amount of activity when only the intensity of the exercise is changed without changing the behavioral scene of the person (with the human motion state as it is). It can be obtained from the approximate expression used. For example, if the fluctuation average is V [G] and the activity is I [METs], the calculation formula for daily activities is the following formula (1), and the calculation formula for walking is the following formula (2). The operational formulas for the above are respectively expressed by the following formula (3). Note that a to d are coefficients obtained by the above approximation, and generally a <b, and the constant e is a value such that the following expressions (2) and (3) are continuous at the second threshold value.

  Therefore, the relationship between the fluctuation average V and the activity amount I in the activity meter of the present embodiment is as shown by a solid line in FIG.

  By the way, the activity amount calculating means 3 has the function of calculating the activity amount as described above, the average of activity amounts per unit time such as one hour or one day, exercise [METs · h], one day exercise. It may be configured to calculate various data (hereinafter referred to as “activity data”) relating to human activities such as amount, calorie consumption, number of steps, and exercise time. In addition, since calculation methods, such as exercise and consumption calories, can use a conventionally well-known method, detailed description is abbreviate | omitted. Further, the activity amount calculation means 3 is configured to store a history of each activity data by storing the activity data in the storage means 5.

  The action scene determination unit 2 and the activity amount calculation unit 3 include, for example, an arithmetic processing unit (not shown) made up of hardware resources such as a microcomputer housed in the casing, and an arithmetic unit for information calculation. This is realized by software that performs processing and the like. In addition to the action scene determination means 2 and the activity amount calculation means 3, the arithmetic processing means exhibits various functions of the activity meter such as a display control means (not shown) for controlling the display means 4. It has the necessary means.

  The display means 4 is composed of an image display device (not shown) such as a liquid crystal display (LCD) and its drive circuit (not shown), and is stored in the storage means 5 by the display control means. The activity data is controlled to be displayed on the image display device. In addition, the operation means includes a switch for on / off operation of the activity meter, a switch for starting calculation of the activity amount, a switch for resetting the display of the activity amount, a switch for switching the activity data to be displayed, etc. It is.

  In the activity meter of the present embodiment described above, for example, if the fluctuation average V of the norm of acceleration obtained by the acceleration detecting means 1 is less than the first threshold, the action scene is determined as “life” by the action scene determining means 2. It is determined that the activity is “activity”, and the amount of activity I is calculated using the above equation (1). If the variation average V is equal to or greater than the first threshold value and less than the second threshold value, the behavior scene determination unit 2 determines that the behavior scene is “walking”, and the amount of activity I is calculated using the above equation (2). Is done. If the variation average V is equal to or greater than the second threshold, the action scene determination unit 2 determines that the action scene is “running”, and the amount of activity I is calculated using the above equation (3).

  Therefore, according to the activity meter of the present embodiment, the determination is made based on the acceleration obtained by the acceleration detecting means 1 (in this embodiment, the average fluctuation of the norm of the acceleration reflecting the magnitude of the acceleration of each axis). Since the amount of activity is calculated according to the action scene, the difference in human action scene can be reflected in the amount of activity, and an accurate amount of activity can be calculated. Moreover, since the behavior scene determination means 2 determines whether the behavior scene is “life activity”, “walking”, or “running”, “life activity”, “walking”, and “running” respectively. Can reflect the difference in activity amount. Furthermore, since the activity amount calculation means 3 changes the arithmetic expression corresponding to each action scene, it can calculate an accurate activity amount as compared with the case where the activity amount is calculated with only one arithmetic expression.

  In addition, in the activity amount calculation means 3, instead of the quadratic formula as shown in the above formula (3), the primary formula as shown in the following formula (4) is used similarly to the above formulas (1) and (2). May be adopted. In this case, b <f, and the constant g is a value such that the following expressions (2) and (4) are continuous at the second threshold value.

  By the way, the action scenes such as “life activity”, “walking”, and “running” mentioned in this embodiment are merely examples, and are not intended to be limited thereto. In calculating the activity amount from the above-mentioned variation average, a data table or the like may be used instead of the arithmetic expressions as shown in the above formulas (1) to (4). Furthermore, although the acceleration detection means 1 in the present embodiment uses an acceleration sensor that detects accelerations of three axes orthogonal to each other, the acceleration detection unit 1 detects accelerations of one axis or two axes orthogonal to each other. An acceleration sensor may be used.

(Embodiment 2)
In the activity meter of the present embodiment, the configuration of the action scene determination unit 2 is different from that of the first embodiment, and the other configurations are the same as those of the first embodiment.

  The action scene determination means 2 in the present embodiment calculates the number of steps [steps / min] per unit time (in this embodiment, 1 minute) from the acceleration obtained by the acceleration detection means 1, and the action scene is determined based on the number of steps per unit time. It is configured to perform scene determination. Here, the number of steps is counted, for example, by counting the number of peaks whose peak value exceeds a predetermined threshold in the norm having the acceleration of each axis obtained by the acceleration detecting means 1 as a vector component. As a method of counting the number of steps of a person from the acceleration obtained by the acceleration detecting means 1, a conventionally known method can be adopted, and detailed description thereof is omitted. In this embodiment, the unit time is 1 minute, but the present invention is not limited to this.

  For example, as shown in FIG. 4, the action scene determination unit 2 determines the action scene as “life activity” if the number of steps per unit time is less than a first threshold (60 in the present embodiment), and If the number of steps per unit time is equal to or greater than a second threshold value (120 in the present embodiment) that is greater than the first threshold value, the action scene is determined to be “running”, and the number of steps per unit time is equal to or greater than the first threshold value. If it is less than the second threshold, the action scene is determined as “walking”.

  Here, the first threshold value is a value serving as a boundary between “life activity” and “walking”. For example, the unit time when the human action scene is switched from “life activity” to “walking” is described above. It can be obtained from the statistical data of the number of steps per hit. Similarly, the second threshold is a value that becomes a boundary between “walking” and “running”. For example, the second threshold value per unit time when the human action scene switches from “walking” to “running” It can be obtained from statistical data on the number of steps.

  According to the activity meter of the present embodiment described above, since the activity amount is calculated according to the action scene determined based on the number of steps per unit time calculated from the acceleration obtained by the acceleration detecting means 1, The difference in action scenes can be reflected in the amount of activity, and an accurate amount of activity can be calculated. Moreover, since the behavior scene determination means 2 determines whether the behavior scene is “life activity”, “walking”, or “running”, “life activity”, “walking”, and “running” respectively. Can reflect the difference in activity amount. Furthermore, since the activity amount calculation means 3 changes the arithmetic expression corresponding to each action scene, it can calculate an accurate activity amount as compared with the case where the activity amount is calculated with only one arithmetic expression.

  In particular, in the activity meter of the present embodiment, since the action scene is determined based on the number of steps per unit time, unlike the first embodiment, the action scene can be determined without depending on the value of the change average. Even in the same case, the action scene can be determined (for example, as shown in the graph of FIG. 3, when the variation average is less than 0.3, the action scene is “life activity” indicated by a solid line or a broken line. The activity amount can be calculated more accurately.

(Embodiment 3)
In the activity meter of the present embodiment, the configuration of the action scene determination unit 2 is different from that of the first embodiment, and the other configurations are the same as those of the first embodiment.

  The action scene determination unit 2 in the present embodiment is a norm (that is, a combined acceleration) in which the magnitude of the acceleration obtained by the acceleration detection unit 1, in this embodiment, the acceleration of each axis obtained by the acceleration detection unit 1 is a vector component. ) To calculate the number of steps per unit time (1 minute in the present embodiment) from the first determination function for determining the action scene based on the fluctuation average (standard deviation) in a predetermined time and the acceleration obtained by the acceleration detecting means 1 And a second determination function for determining an action scene based on the number of steps per unit time.

  Here, as in the first embodiment, the first determination function determines the action scene as “life activity” if the variation average is less than the first threshold (0.3 G in the present embodiment), and the variation described above. If the average is greater than or equal to a second threshold (0.6G in the present embodiment) that is greater than the first threshold, the action scene is determined as “running”, and the variation average is greater than or equal to the first threshold and less than the second threshold. If so, the action scene is determined to be “walking”.

  Similarly to the second embodiment, the second determination function determines the action scene as “life activity” if the number of steps per unit time is less than the first threshold (60 steps / minute in the present embodiment). If the number of steps per unit time is greater than or equal to a second threshold value (120 steps / minute in this embodiment) that is greater than the first threshold value, the action scene is determined to be “running”, and the number of steps per unit time is the first number. The action scene is determined to be “walking” when the threshold is equal to or greater than 1 and less than the second threshold.

  Then, the action scene determination means 2 outputs the determination result to the activity amount calculation means 3 only when the determination results of the first determination function and the second determination function match, and the activity amount calculation means 3 Calculation is performed. That is, the action scene determination means 2 does not correspond to any action scene when the determination results of the first determination function and the second determination function do not match, and the acceleration obtained by the acceleration detection means 1 is For example, it is determined that the activity amount should not be measured, for example, when the activity meter is held by hand without being worn on the body. In this case, the activity amount calculation means 3 does not specify an action scene, so that the activity amount is not calculated.

  Therefore, according to the activity meter of the present embodiment, since the two types of determination are performed by the first determination function and the second determination function, the action scene can be determined accurately, and as a result, the more accurate activity The amount can be calculated.

  In this embodiment, two types of determinations are performed. However, more determinations may be performed, and the determination method is not limited to the above method, and the gist of the present invention. You may change to the extent which does not deviate.

It is a block diagram of the active mass meter of Embodiment 1. It is explanatory drawing in the same as the above. It is a graph which shows the relationship between the fluctuation average of an acceleration, and activity amount. It is explanatory drawing of the active mass meter of Embodiment 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Acceleration detection means 2 Action scene determination means 3 Activity amount calculation means 4 Display means 5 Storage means

Claims (5)

  Acceleration detection means based on the determination result of the acceleration detection means mounted on the human body, the action scene determination means for determining the human action scene based on the acceleration obtained by the acceleration detection means, and the action scene determination means An activity meter, comprising: an activity amount calculating means for calculating an activity amount from the acceleration obtained by the means.   The activity meter according to claim 1, wherein the action scene determination unit is configured to determine whether the action scene is a daily activity, walking, or running.   The activity meter according to claim 1 or 2, wherein the action scene determination means is configured to determine the action scene based on the magnitude of the acceleration obtained by the acceleration detection means.   The action scene determination means is configured to calculate the number of steps per unit time from the acceleration obtained by the acceleration detection means, and to determine a human action scene based on the number of steps. The activity meter according to any one of the above.   The activity amount calculation means has an arithmetic expression used for calculating the activity amount from the acceleration for each action scene, and is configured to select an arithmetic expression to be used based on the determination result of the action scene determination means. The active mass meter according to any one of claims 1 to 4, wherein

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