KR101932132B1 - Apparatus and measuring body fat and method thereof - Google Patents

Abstract

Provided are an apparatus and method for measuring body fat using a bioelectric impedance measurement method. The apparatus for measuring body fat includes a sensing unit for measuring the degree of hydration of the skin of a finger measured on the skin of the finger in contact with the apparatus for measuring body fat and measuring bio impedance for measuring the body fat of a body, and a control unit for calculating a correction value (K) changed according to the degree of hydration of the skin of the finger, correcting the bio impedance using the correction value (K), and measuring the body fat using the corrected bio impedance. Accordingly, the present invention can accurately measure the body fat.

Description

TECHNICAL FIELD [0001] The present invention relates to a body fat measurement apparatus and a body fat measurement method,

The present invention relates to an apparatus and method for measuring body fat, and more particularly, to an apparatus and method for measuring body fat using a bioelectrical impedance measuring method.

The major components of the body are composed of four components: moisture, protein, fat, and minerals. The proportions of these components in body weight vary between 55: 20: 20: 5, depending on gender and individual. These four body components can be known from the body water amount. Protein and body water are the main constituents of muscles and they are related to each other. That is, about 73% of healthy muscles are made of water and the remaining 27% are proteins. The minerals are mainly the bones, and the bones are closely related to the muscle mass. That is, the protein amount and the inorganic mass can be obtained from the body water amount, and the body fat amount, the protein amount and the inorganic mass are subtracted from the body weight to obtain the body fat amount. Currently, the most commonly used method for measuring body fat is bioelectrical impedance analysis (BIA). The bioelectrical impedance method is a method of measuring body fat in view of the inverse relationship between the amount of water content and the electrical resistance of the body.

The bioelectrical impedance method has the advantage that measurement is simple and as early as non-invasive. When sending a weak alternating current electrical signal to the body, electricity flows along a highly conductive body water stream. As the amount of moisture is small, the width and width of the passage through which electricity flows are determined. The measured value is bio-impedance. The principle of calculating the body composition from the bioimpedance is such that a minute alternating current of about 1 mA flows in the frequency band of 50 kHz to the human body. When the current flows through the human body, the human body resistance is measured and the body water amount is obtained by using it. The protein amount and the inorganic mass are obtained from the body water amount, and the body fat amount is obtained by using the protein amount, the inorganic mass and the body weight.

However, when such a bioelectrical impedance method is used, there is a problem that an error of a measured value largely occurs due to a measurement site, for example, a hydration value of the skin. For example, the degree of hydration of an anthropometry site may vary depending on the skin condition of a measurer, such as seasonal humidity, condition before and after hand washing, hyperhidrosis or psoriasis skin, and the result may be an error in the result of measurement of body fat.

No. 10-2005-01015783, an apparatus for measuring body fat using a mobile phone and a method for measuring body fat using the same

The present invention corrects body fat measurement results so that the body fat measurement result does not vary according to the degree of hydration of the skin, and enables accurate bioelectrical impedance measurement to accurately measure body fat mass.

A body fat measurement device according to one aspect of the present invention is a body fat measurement device that measures a degree of hydration of a finger skin measured on a skin of a finger contacted by a body fat measurement device and measures a living body impedance to measure a body fat of the body And a control unit for calculating the correction value K that varies depending on the degree of hydration of the finger skin, correcting the bioimpedance using the correction value K, and measuring the body fat using the corrected bioimpedance do.

The sensing unit measures a finger skin impedance, generates a measurement frequency f ₁ corresponding to the finger skin impedance, and the control unit responds to an impedance value measured in a measurement waiting state that is not in contact with the skin at the measurement frequency f ₁ The correction value K can be calculated by using a value obtained by dividing the value obtained by subtracting the standby frequency f ₀ from the preset reference frequency f _r .

Standby frequency (f ₀₎ may be set in advance is measured. Alternatively, the waiting frequency (f ₀ ) can be measured and used in real time before the body fat measurement device is brought into contact with the skin.

The sensing unit includes an electrode unit that applies a current to the skin of the measurement region and detects a current change signal with respect to the applied current, and an impedance unit that detects a voltage corresponding to the current change signal and measures an impedance value with respect to the detected voltage signal An impedance measurement unit, and a frequency generation unit that generates a frequency corresponding to the measured impedance value.

The control unit controls the electric field strength of the finger skin in the waiting state corresponding to the degree of hydration of the finger skin in the measurement waiting state that is not in contact with the finger skin at the measurement value (E ₁ ) of the electric field intensity corresponding to the finger skin moisture level in the state of contact with the finger skin The correction value K can be calculated by subtracting the measured value E _{0 of the} intensity and dividing the measured value of the subtracted electric field intensity by the value E _r of the predetermined reference electric field intensity.

The measured value E ₀ of the electric field strength in the standby state can be measured and set in advance. The measured value E ₀ of the electric field intensity in the standby state can be measured and used in real time before the body fat measurement device is brought into contact with the skin.

According to another aspect of the present invention, there is provided a method of measuring body fat comprising the steps of measuring finger skin impedance measured on a skin of a finger contacted by a body fat measurement device, generating a measurement frequency f ₁ corresponding to a finger skin impedance Calculating a correction value K that varies according to the degree of skin hydration using a measurement frequency f ₁ and an atmospheric frequency f ₀ corresponding to an impedance value measured in a measurement standby state not in contact with the skin, Measuring the body impedance to measure the body fat of the body, correcting the body impedance using the correction value K, and measuring body fat using the corrected body impedance.

In the step of calculating the correction value K, the correction value K can be calculated by using a value obtained by dividing the value obtained by subtracting the standby frequency f ₀ from the measurement frequency f ₁ by the reference frequency f _r .

In the body fat measuring method according to an aspect of the invention, the method comprising: measuring a measure of the field strength (E ₁₎ is measured on the skin of a body fat measurement device in contact fingers, of the field strength measured value (E ₁₎ Calculating a correction value (K) that varies according to the degree of skin hydration using a measured value (E ₀ ) of the atmospheric state electric field strength measured in a measurement waiting state not in contact with the skin, Measuring the bioimpedance, correcting the bioimpedance using the correction value (K), and measuring body fat using the corrected bioimpedance.

In calculating the correction value K, a value obtained by subtracting the measured value E ₀ of the standby state electric field intensity from the measured value E _{1 of the} electric field intensity is divided by the preset reference electric field intensity value E _r The correction value K can be calculated using the value.

According to the present invention, the accuracy of body fat measurement can be improved by correcting the bioimpedance value that is the basis of body fat measurement, taking into account that the bioimpedance is related to the hydration of the skin.

1 is a block diagram showing a configuration of a body fat measurement device according to an embodiment of the present invention.
2 is a block diagram showing a configuration of a body fat measurement device according to another embodiment of the present invention.
3 is a block diagram showing an example of the configuration of the electrode portion of Fig.
FIG. 4 is a graph showing the operation of the sensing unit of the body fat measurement apparatus of FIG. 1;
FIG. 5 is a graph showing the degree of skin hydration according to the frequency change of the body fat measurement device of FIG. 1;
6 is a flowchart illustrating a method of measuring body fat according to an embodiment of the present invention.
FIG. 7 is a table showing measurement values of a living body impedance corrected by applying a measurement method of an impedance for measuring body fat according to an embodiment of the present invention.
FIG. 8 is a table showing error rates of corrected bioimpedance measurement values according to an embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. In addition, the terms described below are defined in consideration of the functions of the present invention, which may vary depending on the intention of the user, the operator, or the custom. Therefore, the definition should be based on the contents throughout this specification.

1 is a block diagram showing a configuration of a body fat measurement device according to an embodiment of the present invention.

The body fat measurement apparatus 100 according to an embodiment of the present invention includes a sensing unit 110, a power supply unit 120, a controller 130, a storage unit 140, a display unit 150, a communication unit 160, 170).

The sensing unit 120 measures the degree of hydration of the finger skin, which is measured with respect to the skin of the finger contacted by the body fat measurement apparatus 100, and measures the bioimpedance to measure the body fat of the body.

The sensing unit 120 may use an impedance measuring method and a capacitance measuring method to measure the skin hydration degree, but it is not limited to a specific method of measuring the skin hydration degree. The impedance measurement method is a method of measuring a change in impedance depending on the degree of hydration of the epidermis by flowing a fine current through the skin. The electrostatic capacity method is a method of measuring the intensity of an electric field that passes through an electric field to the skin and changes depending on the degree of skin hydration.

The control unit 130 calculates a correction value K that changes according to the hydration degree of the finger skin, corrects the living body impedance using the correction value K, and measures the body fat using the corrected living body impedance.

When the sensing unit 120 measures the finger skin moisture content by the impedance measuring method, the finger skin impedance measured with respect to the skin of the finger contacted by the body fat measurement apparatus 100 is measured, and the impedance of the finger corresponding to the finger skin impedance The measurement frequency (f ₁ ) is generated, and the body impedance is measured to measure the body fat of the body. The finger skin impedance and the bioimpedance may be measured simultaneously or sequentially.

The sensing unit 120 may include an electrode unit 112, an impedance measuring unit 114, and a frequency generating unit 116 when the sensing unit 120 measures finger skin moisture level by an impedance measuring method. have.

The electrode portion 112 may be configured to include a plurality of electrodes. The electrode unit 112 applies a current to the skin of the measurement site and detects a current change signal with respect to the applied current. A plurality of electrodes provided in the electrode unit 112 may be configured in parallel depending on the type of polarity (+ polarity, - polarity). The + electrode indicates the type of the current to which the current is applied for skin hydration and body fat measurement, and the - polarity can indicate the type of electrode that senses the current change signal changed according to the applied current.

The current condition applied to the electrode unit 112 to measure the finger skin impedance may be different from the current condition applied to the electrode unit 112 to measure the bioimpedance and the current condition applied through the electrode unit 112. [ For example, in order to measure the finger skin impedance, a fine alternating current of about 0.5 mA can be applied in the frequency band of 50 kHz through the electrode unit 112. In order to measure the bioimpedance, Lt; RTI ID = 0.0 > 1mA < / RTI > When such an alternating current is applied, it affects the alternating current which is applied according to the degree of skin hydration of the finger, so that an error occurs in the impedance measurement value depending on the skin moisture degree of the finger.

The portion of the skin where the electrode unit 112 is contacted may be the same or different from that of the finger skin impedance measurement and the bioimpedance measurement. That is, the electrode portion 112 may be brought into contact again with the finger portion where the electrode portion 112 for measuring the finger skin impedance is in contact with, so that the living body impedance may be measured. Or bioimpedance may be measured through other measurement sites, such as the palms and soles, in addition to the fingertip contacted to measure finger skin impedance.

The electrode unit 112 may be constituted by an electrode for measuring the finger skin impedance and an electrode for measuring the bioimpedance, or may be formed separately. For example, the control unit 130 may control the electrode unit 112 to measure the finger skin impedance, and then the electrode unit 112 to measure the bioimpedance. Alternatively, as described later in Fig. 3, the electrode portion 310 for measuring the skin skin hydration degree and the electrode portion 320 for measuring the fat saturation may be separately formed.

The impedance measuring unit 114 detects a voltage corresponding to the current change signal and measures an impedance value for the detected voltage signal. To this end, the impedance measuring unit 114 includes a signal measuring module (not shown) for detecting a voltage corresponding to the current change signal and an impedance measuring module (not shown) for measuring an impedance value for the measured voltage signal . The impedance value can be measured using the current I sensed at the electrode portion 112 and the voltage V measured at the signal measurement module.

The signal measurement module may be configured to measure a voltage signal using a signal transmitted from a plurality of electrodes. The signal measurement module may be constituted by a plurality of resistors which are respectively provided at both ends of two electrodes out of a plurality of electrodes and which are arranged in parallel with each other.

When the skin hydration degree is high, the electric resistance decreases and the current flows well. When the body fat is high, the electric resistance increases and the current does not flow well. Therefore, the skin hydration and the skin impedance become inversely proportional to each other.

The frequency generator 116 generates a frequency corresponding to the measured impedance value. Specifically, the frequency generation unit 116 generates a measurement frequency f ₁ corresponding to the finger skin impedance measured for the skin of the finger contacted by the body fat measurement apparatus 100. According to one embodiment, the frequency generator 116 may generate the frequency in inverse proportion to the measured impedance value. Since the measurement frequency f ₁ varies depending on the degree of hydration of the finger skin, it can be defined as the value of the moisture state of the finger skin.

The measurement frequency (f ₁₎ is a digital pulse signal corresponding to the impedance values measured as shown in Figure 4 which will be described later. The frequency generator 116 may be configured to adjust the resolution of the output frequency.

In measuring the skin moisture content of the capacitive system, the sensing unit 120 may be configured to include a plurality of electrodes inserted in the insulator and a module for measuring the strength of the electric field measured through the electrodes.

The control unit 130 may include a hydration level measuring unit 132 and a body fat measuring unit 134.

In the case of the impedance measurement method, the control unit 130 changes the skin moisture level using the measurement frequency f ₁ and the standby frequency f ₀ corresponding to the impedance value measured in the measurement waiting state not in contact with the skin It is possible to calculate the correction value K, correct the bioimpedance using the correction value K, and measure the body fat using the corrected bioimpedance.

The degree of hydration measuring unit 132 of the control unit 130 calculates the degree of hydration K by using a value obtained by dividing the value obtained by subtracting the waiting frequency f ₀ from the measuring frequency f ₁ by a preset reference frequency f _r , Can be calculated. Here, the standby frequency (f ₀₎ may be set in advance is measured. In addition, the waiting frequency (f ₀ ) can be measured and used in real time before the body fat measurement apparatus 100 is brought into contact with the skin. The preset reference frequency f _r can be experimentally determined to be the value at which the body fat measurement value is the least error.

Alternatively, in the case of measuring the finger skin moisture content by the electrostatic capacity method, the moisture content degree measuring unit 132 of the control unit 130 may measure the finger skin skin moisture level in the state of contact with the finger skin, The measured value E ₀ of the electric field intensity in the waiting state corresponding to the degree of hydration of the finger skin is subtracted from the measured value E ₁ in a waiting state in which the finger skin is not in contact with the finger, The correction value K can be calculated using the value divided by the value E _r of the electric field strength. The measured value E ₀ of the electric field strength in the standby state can be measured and set in advance. The measured value (E ₀ ) of the electric field strength in the standby state may be measured and used in real time before the body fat measurement device is brought into contact with the skin. The value of the reference field strength (E _r ) can be empirically determined with the body fat measurement value being the least error.

The body fat measurement unit 134 corrects the bioimpedance using the correction value K received from the hydration degree measurement unit 132 and calculates the body fat saturation according to the body composition calculation formula according to the bioelectrical impedance method using the corrected bioimpedance Can be measured. Alternatively, the body fat measurement unit 134 directly calculates the correction value K, corrects the bioimpedance using the calculated correction value K, and calculates the body composition based on the bioelectrical impedance method using the corrected bioimpedance Body fat can also be measured according to the formula.

Meanwhile, the hydration degree measuring unit 132 of the control unit 130 measures the degree of skin hydration using the atmospheric frequency f ₀ and the measurement frequency f ₁ generated corresponding to the impedance value measured in the measurement waiting state . At this time, the control unit 130 can correct the deviation of the measurement frequency f ₁ using the standby frequency f ₀ and measure the skin hydration using the corrected measurement frequency f ' ₁ . Also, the control unit 130 can measure skin hydration using a graph or table information showing the relationship of the skin hydration degree corresponding to the frequency (f ' ₁ ) of the frequency.

As described above, the sensing unit 110 can generate in real time the standby frequency f ₀ corresponding to the impedance value measured in the measurement standby state of the body fat measurement apparatus 100. As described above, the use of the atmospheric frequency (f ₀ ) generated in real time every time the body fat measurement is performed on the skin, compared with the method of calibrating the measurement frequency using the preset and fixed waiting frequency (f ₀ ) It is possible to reduce the deviation of the measured value of the body fat and the resultant value of the skin hydration according to the characteristic of the component between the skin. That is, the atmospheric frequency (f ₀ ) generated in real time at each time of body fat measurement functions as deviation correction data between the products of the body fat measurement devices, thereby improving the product reliability of the body fat measurement device 100.

In addition, the control unit 130 based on comparison of the storage unit 140, a reference frequency (f _r), the standby frequency measurements in real-time (f ₀₎ is set which is stored in advance or the like, and the measured air frequency (f ₀₎ is set If the frequency f _r deviates from a certain range, a message indicating that measurement preparation for accurate measurement has not been completed can be generated and notified through the display unit 150 or the like.

The power supply unit 120 supplies power to each component of the body fat measurement apparatus 100 and supplies power to the sensing unit 110 and the controller 130 as shown in FIG. When the controller 130 detects a power switch (not shown) provided outside the body fat measurement apparatus 100 and transmits the power supply start signal to the power supply unit 120 in the controller 130, The controller 120 may be configured to supply power to the sensing unit 112 to generate a frequency.

The storage unit 140 may temporarily store the measured values of the measured frequency f ₀ and the measured frequency f ₁ and may use the measured values by the controller 130. In addition, the storage unit 140 may store a body fat measurement application that performs body fat measurement by a bioelectrical impedance measurement method. In addition, the storage unit 140 may store information of a graph or a tabular form indicating the degree of skin hydration corresponding to the frequency. For example, a graph showing the degree of skin hydration corresponding to frequency is as shown in FIG. 5 to be described later. Also, the storage unit 140 may store a preset reference frequency f _r . The storage unit 140 may be incorporated in the control unit 130 or may be installed outside the device 100.

The display unit 150 may include an LED device, a display, and the like. The display unit 150 may display a power on / off state, a wireless communication connection state, a measurement waiting state, and a state under measurement according to the LED blinking method under the control of the controller 130. For example, depending on the change of the blinking period of the LED, the body fat measurement apparatus 100 can indicate whether it is in a wireless communication connection state, a measurement waiting state, and a measurement state.

The communication unit 160 performs wire / wireless communication with an external terminal (not shown). The communication unit 160 may be configured to include various communication interfaces such as a wired interface, a Bluetooth interface, and a Wi-Fi interface. The external terminal may be various types of terminals such as a cellular phone, a smart phone, a personal computer, and a laptop computer. According to an embodiment of the present invention, the body fat measurement apparatus 100 can start the body fat measurement in response to an instruction of the external terminal transmitted through the communication unit 160, and the body fat measurement result is transmitted to the external terminal And the external terminal can display the received body fat measurement result on the display window.

The switch unit 170 controls power supply to the body fat measurement apparatus 100, and in particular, supplies power to the control unit 130 and the sensing unit 110. The switch unit 170 is a normal power switch operated by a user and informs the control unit 130 that the power switch is turned on when the power switch is pressed, Lt; / RTI > The switch unit 170 senses whether or not the electrode of the electrode unit 112 is in contact with the skin and supplies the power to the electrode unit 112 only when the electrode is in contact with the skin to measure the degree of skin hydration So as to reduce unnecessary power consumption. Accordingly, the power supply unit 120 can supply power to the sensing unit 110 according to the power supply of the switch unit 170 and the command of the controller 130.

As a method for measuring the degree of hydration, a method in which the level of the direct current or the alternating voltage is changed corresponding to the impedance value is used, and the sensor output itself is an analog signal, so a separate analog digital converter is needed. However, when the degree of hydration is measured according to an embodiment of the present invention, when the frequency signal f ₁ , which is a digital signal corresponding to the impedance value, is generated, the sensor output itself corresponding to the sensing unit 110 is a digital signal There is no need to use an analog digital converter for separate data processing.

In addition, in the conventional hydration measurement method, the sensed voltage value is influenced by the battery charging state of the power source, thereby affecting the impedance value measured thereby, and the accuracy of skin hydration is lowered. However, According to the embodiment, the degree of hydration can be improved by calculating the skin hydration degree using the digital measurement frequency f ₁ corresponding to the measured impedance value. In addition, the resolution of the output frequency can be adjusted so that the resolution of the digital signal is limited according to the specifications of the conventional analog digital converter.

2 is a block diagram showing a configuration of a body fat measurement device according to another embodiment of the present invention.

The body fat measurement apparatus 200 of FIG. 2 is different from the body fat measurement apparatus 200 of FIG. 1 in that the sensing unit 100 of the body fat measurement apparatus 100 of FIG. 1 is divided into the first sensing unit 210 and the second sensing unit 220 And is the same as the configuration of the body fat measurement apparatus 100 of Fig.

The first sensing unit 210 may include an electrode unit 212 for measuring the skin skin hydration degree, a first impedance measuring unit 214, and a frequency generating unit 216. The first impedance measuring unit 114 detects the voltage corresponding to the current change signal using the electrode unit 212 for measuring the skin skin hydration degree and measures the impedance value for the detected voltage signal. The frequency generator 216 generates a frequency corresponding to the measured impedance value. Specifically, the frequency generation unit 116 generates a measurement frequency f ₁ corresponding to the finger skin impedance measured for the skin of the finger contacted by the body fat measurement apparatus 100. The frequency generation unit 116 may transmit the measurement frequency f ₁ to the hydration degree measurement unit 132.

The second sensing unit 210 may include a body fat measurement electrode unit 222 and a second impedance measurement unit 224. The second impedance measurement unit 224 detects the voltage corresponding to the current change signal using the body fat measurement electrode unit 222 and measures the bioimpedance value with respect to the detected voltage signal. The second impedance measurement unit 224 may transmit the measured bioimpedance value to the body fat measurement unit 134.

Here, the voltage detection sensors included in the first impedance measurement unit 114 and the second impedance measurement unit 224 use sensors of the same standard.

3 is a block diagram showing an example of the configuration of the electrode portion of Fig.

The electrode unit 112 of FIG. 1 may include an electrode unit 310 for measuring the skin skin hydration degree and an electrode unit 320 for measuring the body fat saturation. The plurality of electrodes provided in the electrode portion 310 for measuring the skin skin hydration degree and the electrode portion 320 for measuring the fat saturation may be configured in parallel. The plurality of electrodes are arranged in parallel, and it is possible to increase the reliability of measured skin impedance values by simultaneously measuring various portions of the skin and averaging the measured impedance values at various portions.

The finger skin moisture measurement electrode unit 310 may include a first electrode 312, a second electrode 314, a third electrode 316, and a fourth electrode 318. The first electrode 312 is an electrode that contacts the left thumb finger, the second electrode 314 is an electrode that contacts the left index finger skin, the third electrode 316 is an electrode that contacts the right thumb finger And the fourth electrode 318 may be an electrode that contacts the right index finger skin. The first electrode 312 and the third electrode 316 may be a pair of current electrodes and the second electrode 314 and the fourth electrode 318 may be a pair of voltage electrodes.

The body fat measurement electrode unit 320 may include a fifth electrode 322, a sixth electrode 324, a seventh electrode 326, and an eighth electrode 328. The fifth electrode 322 is an electrode that contacts the skin of the left palm region, the sixth electrode 324 is an electrode that contacts the skin of the right palm region, the seventh electrode 326 is an electrode that contacts the skin of the left foot region And the eighth electrode 328 may be an electrode contacting the skin of the right foot region.

4 is a graph showing the operation of the sensing unit 110 of the body fat measurement apparatus 100 of FIG.

As described above, the standby frequency f _o represents the standby frequency generated in the measurement standby state, and the measurement frequency f ₁ represents the measurement frequency generated in the finger skin moisture measurement state. As described above, the impedance measuring unit 114 of the sensing unit 110 of FIG. 1 measures an impedance value of the finger skin hydration measuring state, and the frequency generating unit 116 measures an impedance value measured in the measuring state It is possible to generate a corresponding measurement frequency f ₁ . The impedance measuring unit 114 of the sensing unit 110 measures the impedance value in the waiting state of the skin skin hydration and the frequency generating unit 116 measures the impedance value measured in the waiting state of the skin skin hydration (F ₀ ) to be generated.

The control unit 130 calculates a correction value K that varies according to the degree of skin hydration using a measurement frequency f ₁ and an atmospheric frequency f ₀ corresponding to an impedance value measured in a measurement waiting state not in contact with the skin The living body impedance can be corrected using the correction value K, and the body fat can be measured using the corrected living body impedance.

The control unit 130 may include a hydration level measuring unit 132 and a body fat measuring unit 134. The hydration degree measurement unit 132 may calculate the correction value K by using a value obtained by dividing the value obtained by subtracting the standby frequency f ₀ from the measurement frequency f ₁ by a preset reference frequency f _r . The value obtained by subtracting the waiting frequency (f ₀ ) from the measuring frequency (f ₁ ) is a value shifted according to the impedance of the finger of the person to be measured, and therefore can be defined as the value of the finger skin moisture of the person to be measured.

For example, it is assumed that the preset reference frequency f _r is 13,000 Hz, the measured standby frequency f ₀ is 2,100 Hz, and the measured frequency f ₁ is 15,600 Hz. In this case, the correction value K = (15,600-2,100) /13,000=13,500/13,000 = 1.038 can be calculated.

The body fat measurement unit 134 receives the correction value K from the hydration degree measurement unit 132 when the living body impedance is measured at 600 ?, multiplies the living body impedance measurement value by the correction value K, Value of 622.8?, And the body fat can be measured using the corrected living body impedance value of 622.8?.

In addition, the control unit 130 may calculate the skin hydration degree using the measured frequency f ₁ by using the measured frequency f ₀ in real time and using the corrected measurement frequency f ₂ . For example, the control unit 130 calculates the correction value K2 (here, K2 = f _r2 / f _O ) using the reference frequency f ₀ and the reference frequency f _r2 preset in the body fat measurement apparatus 100 , And the corrected measurement frequency f ₂ can be calculated by multiplying the measurement frequency f ₁ by the correction value. Accordingly, the control unit 130 can measure the skin hydration degree corresponding to the corrected measurement frequency f ₂ with reference to the graph of FIG.

5 is a graph showing skin hydration according to a frequency change of the body fat measurement apparatus 100 of FIG.

The abscissa of the graph in Fig. 5 represents the frequency (Hz), and the ordinate represents the degree of skin hydration (%). The graph of FIG. 5 shows the relationship of the skin hydration degree (%) to the frequency (Hz), which is stored in the storage unit 140 of FIG. 1 and can be used by the control unit 130 for skin hydration calculation . In FIG. 5, the standby frequency (f ₀ ) is the lowest point of the graph, about 2000 Hz, and the skin hydration can be calculated according to the measurement frequency.

6 is a flowchart illustrating a method of measuring body fat according to an embodiment of the present invention.

The body fat measurement apparatus 100 measures the finger skin impedance measured on the skin of the finger contacted by the body fat measurement apparatus 100 (610).

The body fat measurement apparatus 100 generates a measurement frequency f ₁ corresponding to the finger skin impedance (620).

The body fat measurement apparatus 100 measures a correction value K (k) that changes according to the degree of skin hydration using a measurement frequency f ₁ and an atmospheric frequency f ₀ corresponding to an impedance value measured in a measurement waiting state not in contact with the skin, (630).

The body fat measurement apparatus 100 may display a message informing re-measurement when the value obtained by subtracting the standby frequency f ₀ from the measurement frequency f ₁ falls within a predetermined measurement error range.

The body fat measurement device 100 measures the body impedance to measure the body fat of the body (640).

The body fat measurement apparatus 100 corrects the bioimpedance using the correction value K (650).

The body fat measurement device 100 measures the body fat using the corrected bioimpedance (660).

In the case of the capacitive type, the body fat measurement device measures the value of which is measured against the skin of a contact finger electrical field strength (E ₁₎ to the measuring step and, in the electric field strength measurements of (E ₁₎ and that is not in contact with the skin using the measured values (E ₀₎ of a standby electric field intensity measured in the measurement-waiting state, the step of calculating a correction value (K) which is changed in accordance with FIG skin moisture content is performed, and the living body impedance is measured, the correction value (K ), And the body fat measurement can be performed using the corrected bioimpedance.

FIG. 7 is a table showing measurement values of a living body impedance corrected by applying a measurement method of an impedance for measuring body fat according to an embodiment of the present invention. FIG. 8 is a table showing error rates of corrected bioimpedance measurement values according to an embodiment of the present invention.

7, the table 710 shows the measured values of the impedance of the finger according to the conventional technique and the measured impedance values of the bioimpedance corrected according to the embodiment of the present invention, when the bioimpedance of the measurement subject is modeled as 610? . In addition, the table 720 may include a finger skin impedance frequency in the case of modeling the bioimpedance of a subject to be measured to 600?, Impedance measurement values according to existing techniques and bioimpedance values corrected according to an embodiment of the present invention It is a table to compare.

Referring to FIG. 8, according to the related art, the bioimpedance value of the measurement subject shows an error of 3.8% at maximum. However, according to the embodiment of the present invention, The measurement value of bioimpedance shows a maximum error of 0.8%, and the measurement error is greatly reduced.

One aspect of the present invention may be embodied as computer readable code on a computer readable recording medium. The code and code segments implementing the above program can be easily deduced by a computer programmer in the field. A computer-readable recording medium includes all kinds of recording apparatuses in which data that can be read by a computer system is stored. Examples of the computer-readable recording medium include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical disk, and the like. The computer-readable recording medium may also be distributed over a networked computer system and stored and executed in computer readable code in a distributed manner.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Therefore, the scope of the present invention should not be limited to the above-described embodiments, but should be construed to include various embodiments within the scope of the claims.

100: Body fat measurement device 110:
120: power supply unit 130:
140: storage unit 150: display unit
160: communication unit 170: switch unit

Claims (12)

A body fat measurement device comprising:
A sensing unit for measuring the degree of hydration of the finger skin measured on the skin of the finger contacted by the body fat measurement device and measuring the bioimpedance to measure the body fat of the body;
A control unit for calculating a correction value K that varies depending on the degree of hydration of the finger skin, correcting the bioimpedance using the correction value K, and measuring body fat using the corrected bioimpedance; Wherein the body fat measurement device comprises: The method according to claim 1,
Wherein the sensing unit measures a finger skin impedance and generates a measurement frequency f ₁ corresponding to the finger skin impedance, and the control unit calculates an impedance value measured at a measurement frequency f ₁ in a measurement standby state that is not in contact with the skin And calculates a correction value (K) by using a value obtained by dividing a value obtained by subtracting a corresponding standby frequency (f ₀ ) by a preset reference frequency (f _r ). 3. The method of claim 2,
Wherein the standby frequency (f ₀ ) is measured and set in advance. 3. The method of claim 2,
Wherein the atmospheric frequency (f ₀ ) is measured and used in real time before the body fat measurement device is brought into contact with the skin. 3. The method of claim 2,
The sensing unit includes:
An electrode unit for applying a current to the skin of the measurement site and detecting a current change signal with respect to the applied current;
An impedance measuring unit that detects a voltage corresponding to the current change signal and measures an impedance value with respect to the detected voltage signal; And
A frequency generator for generating a frequency corresponding to the measured impedance value; Wherein the body fat measurement device comprises: The method according to claim 1,
Wherein the control unit is configured to control the degree of hydration of the finger skin in a waiting state in which the finger skin is not in contact with the finger skin at a measured value E ₁ of the electric field strength corresponding to the degree of skin skin hydration in a state of contact with the finger skin The correction value K is calculated by subtracting the measured value E ₀ of the electric field strength and dividing the measured value of the subtracted electric field intensity by the value E _r of the predetermined reference electric field strength Body fat measurement device. The method according to claim 6,
Wherein the measured value E ₀ of the electric field strength in the standby state is measured and set in advance. The method according to claim 6,
Wherein the measurement value E ₀ of the electric field strength in the standby state is measured and used in real time before the body fat measurement device is brought into contact with the skin. A method of measuring body fat,
Measuring a finger skin impedance measured for a skin of a finger contacted by the body fat measurement device;
Generating a measurement frequency f ₁ corresponding to the finger skin impedance;
Calculating a correction value (K) that varies according to the degree of skin hydration using a measurement frequency (f ₁ ) and an atmospheric frequency (f ₀ ) corresponding to an impedance value measured in a measurement standby state not in contact with the skin;
Measuring a bioimpedance to measure a body fat of the body;
Correcting the bioimpedance using the correction value (K); And
Measuring body fat using the corrected bioimpedance; And measuring the body fat. 10. The method of claim 9,
The correction value K is calculated by using a value obtained by dividing the value obtained by subtracting the standby frequency f ₀ from the measurement frequency f ₁ by the reference frequency f _{r in} the step of calculating the correction value K A method for measuring body fat. A method of measuring body fat,
Measuring a measurement value (E ₁ ) of the electric field strength measured with respect to the skin of the finger contacted by the body fat measurement device;
Using the measured value of electric field strength (E ₁₎ and the measured values of the standby electric field intensity measured in the measurement-waiting state is not in contact with the skin (E ₀₎ for calculating a correction value (K) is varied depending on the skin hydration step;
Measuring a bioimpedance to measure a body fat of the body;
Correcting the bioimpedance using the correction value (K); And
Measuring body fat using the corrected bioimpedance; And measuring the body fat. 12. The method of claim 11,
In calculating the correction value K, a value obtained by subtracting the measured value E ₀ of the standby state electric field intensity from the measured value E _{1 of the} electric field intensity is divided by the preset reference electric field intensity value E _r And calculating a correction value (K) using the value of the correction value (K).

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