JP2010005033A - Walking motion analyzer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To determine right and left balance of walking motion simultaneously with walking parameters, such as number of steps, walk distance, walking speed, or a stride, without increasing the number of axial directions whose accelerations are detected. <P>SOLUTION: A sensor section 1, which is a uniaxial acceleration sensor, is attached to the body and detects acceleration of body parts due to walking in a uniaxial direction except the right and left axis directions. A computational processing section 3 extracts a feature value (the maximum value, the minimum value or the like) of an acceleration waveform generated from the detection result of the sensor section 1, and determines whether the right and left balance of the walking motion is normal or not using the feature values of the acceleration waveform in a standing leg period that correspond respectively to the motions of the right and left legs in a walking cycle. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a walking motion analysis device for determining a walking motion of a subject from a change in acceleration of a body part caused by walking.

  In recent years, due to the heightened health consciousness, not only walking but also how to walk beautifully with good posture or how to enhance the exercise effect has been analyzed.

  Conventionally, as a walking analysis method, a method of photographing a walking image, a method of analyzing a change with the passage of time when the foot contacts the floor surface from the sole pressure or the floor reaction force have been developed. For example, Patent Document 1 discloses a technique for measuring a subject's walking speed, leg spacing, left-right wobbling, and the like from a temporal change in a contact position between a walking image and each leg. Patent Document 2 discloses a method for scoring walking evaluation from a foot pressure distribution during walking.

  As a method other than walking images and sole pressure, a method has been developed in which an accelerometer is attached to the body, and parameters relating to walking are analyzed from changes in acceleration of the body part caused by walking. As a general walking analysis method using an accelerometer, the vertical acceleration of the waist associated with walking is detected, the number of steps when the output signal exceeds a preset threshold is set as the number of steps, and the step length previously input There are methods for calculating the walking distance by multiplying and estimating the stride from the acceleration. For example, Patent Document 3 discloses a technique that measures the number of steps from the number of times a walking signal is generated based on the vertical movement of a human body detected by the output of an acceleration sensor. Patent Document 4 discloses a method in which a calculation unit calculates a walking pitch, a stride, and a walking speed of a subject using a period and an amplitude derived from acceleration data.

The conventional techniques of walking evaluation using acceleration as in Patent Documents 3 and 4 are based on the vertical axis direction and the traveling axis direction by an acceleration sensor attached to the waist and back of the body near the center of gravity of the body for daily walking management. The walking parameters such as the number of steps, walking distance, walking speed, and stride are presented from the acceleration data. This is because, in the acceleration waveform output along with the acceleration change of the body part due to walking, the timing of the walking movement such as the left and right legs touching the ground or toing off the toe is in the vertical axis direction or the traveling axis direction. This is based on the fact that it corresponds to the waveform peak and maximum amplitude of acceleration.
JP 2002-345785 A Japanese Patent No. 3725788 Japanese Patent No. 2675842 JP 2006-118909 A

  However, in terms of analyzing how to walk, walking parameters such as the number of steps, walking distance, walking speed, and stride are not enough, and it is important that you can walk in a balanced manner in the left-right direction. Become an element.

  Conventionally, in order to see that you can walk in a balanced manner in the left-right direction, you can change the changes over time when the foot touches the floor mainly from the method of taking a walking image or the pressure of the soles or the floor reaction force. Analyzing methods were used. However, such a method has a problem that the measurement environment is greatly limited because an image acquisition camera and a pressure / floor reaction force sensor sheet need to be installed.

  As a method of solving the above problem, a method of adding a lateral acceleration sensor and analyzing the symmetry of the acceleration waveform can be considered.

  However, when an acceleration sensor in the left-right axis direction is added, there are problems that the number of axes to be detected increases, the structure becomes complicated, and the continuous operation time is shortened due to an increase in power consumption.

  The present invention has been made in view of the above points. The purpose of the present invention is to increase the number of steps, the walking distance, the walking speed, and the walking parameters, such as the walking length, and the walking motion without increasing the axial direction for detecting acceleration. An object of the present invention is to provide a walking motion analyzer capable of determining the left / right balance.

  The invention according to claim 1 is generated from a uniaxial acceleration sensor that detects acceleration in a single axis direction other than the left and right axis directions of a body part that is worn on the body and is caused by walking, and a detection result of the uniaxial acceleration sensor. An arithmetic processing unit that extracts the feature amount of the acceleration waveform and determines whether the right and left balance of the walking motion is normal using the feature amount of the acceleration waveform in the stance phase corresponding to the motion of the left and right legs in the walking cycle. It is characterized by providing.

  According to a second aspect of the present invention, in the first aspect of the invention, the uniaxial acceleration sensor is attached to the body such that the single axis direction is a vertical axis direction.

  According to a third aspect of the present invention, in the first aspect of the invention, the uniaxial acceleration sensor is attached to the body such that the single axis direction is a traveling axis direction in which the body walks. Features.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the arithmetic processing unit extracts an extreme value of an acceleration waveform as a feature amount of the acceleration waveform.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to third aspects, the arithmetic processing unit extracts a magnitude of a maximum amplitude of the acceleration waveform as a feature amount of the acceleration waveform. .

  The invention according to claim 6 is the invention according to any one of claims 1 to 3, wherein the arithmetic processing unit extracts an area surrounded by an acceleration waveform and a time axis as a feature amount of the acceleration waveform. Features.

  The invention according to claim 7 is the invention according to any one of claims 1 to 3, wherein the arithmetic processing unit corresponds to an acceleration waveform in a stance phase corresponding to a motion of the left leg in a walking cycle and a motion of the right leg. Using the correlation function with the acceleration waveform in the stance phase, it is determined whether or not the left-right balance of the walking motion is normal.

  According to an eighth aspect of the present invention, in any one of the first to seventh aspects of the present invention, the storage device stores in advance the characteristic amount of the reference waveform of the acceleration waveform, and the arithmetic processing unit includes the single-axis acceleration sensor. It is determined whether the right and left balance of the walking motion is normal by comparing the feature amount of the acceleration waveform generated from the detection result with the feature amount of the reference waveform stored in the storage unit. And

  According to a ninth aspect of the invention, in the eighth aspect of the invention, the reference waveform stored in the storage unit is an acceleration waveform detected in advance by the uniaxial acceleration sensor.

  A tenth aspect of the present invention provides the storage device according to any one of the first to ninth aspects, further comprising a storage unit that stores a reference value of the feature value of the acceleration waveform in advance, and the arithmetic processing unit includes the single-axis acceleration sensor. The walking motion is determined by comparing the feature amount of the acceleration waveform generated from the detection result of the above and the reference value stored in the storage unit.

  The invention of claim 11 is the invention of claim 10, wherein the reference value stored in the storage unit is a value calculated from an acceleration waveform detected in advance by the one-axis acceleration sensor. .

  A twelfth aspect of the invention is characterized in that in the invention of any one of the first to eleventh aspects, an output section is provided for outputting a walking motion determination result determined by the arithmetic processing section.

  According to the first aspect of the present invention, by using the acceleration in the single axis direction other than the left and right axis of the body detected by the single axis acceleration sensor, walking with a simple configuration as compared with the case of using the acceleration in the three axis direction. The left / right balance of the operation can be determined.

  According to the second aspect of the present invention, it is possible to detect the acceleration in the other axial directions only by detecting the acceleration in the vertical axis direction necessary for calculating the walking parameters such as the number of steps, the walking distance, the walking speed, and the step length. The right and left balance of the walking motion can be determined together with the walking parameters such as the number of steps, the walking distance, the walking speed, and the step length.

  According to the invention of claim 3, the acceleration in the direction of the traveling axis necessary for calculating the walking parameters such as the number of steps, the walking distance, the walking speed, and the stride is detected, and the acceleration in the other axial direction is detected. The right and left balance of the walking motion can be determined together with the walking parameters such as the number of steps, the walking distance, the walking speed, and the step length.

  According to the fourth aspect of the present invention, an extreme value that can be extracted by simple signal processing from continuous acceleration waveform signals can be used as the feature amount of the acceleration waveform. Can be determined.

  According to the fifth aspect of the present invention, by using the maximum amplitude of the continuous acceleration waveform signal as the feature value of the acceleration waveform, both directions within the same axis (in the vertical axis direction, the vertical upward direction and the vertical downward direction, the traveling axis) If it is a direction, it is possible to perform analysis on the forward direction and the backward direction at a time, and the left-right balance of the walking motion can be determined in detail.

  According to the invention of claim 6, by using the area calculated from the continuous waveform signal and the time axis as the feature value of the acceleration waveform, the analysis with the index reflecting the entire movement of the left and right legs in the walking cycle can be performed. And the left-right balance of the walking motion can be determined in more detail.

  According to the invention of claim 7, the left / right balance of the walking motion can be determined in more detail by using the correlation function between the acceleration waveform in the left leg motion and the acceleration waveform in the right leg motion.

  According to the invention of claim 8, by comparing the feature amount of the acceleration waveform generated from the detection result with the feature amount of the reference waveform, the right and left of the walking motion is determined based on the difference from the reference time (during normal walking). Balance can be determined.

  According to the ninth aspect of the present invention, the left / right balance of the walking motion can be determined based on the degree of change of the subject himself / herself since the previous measurement by using the subject's own measurement waveform as the reference waveform.

  According to the invention of claim 10, by using the acceleration in the single axis direction other than the left and right axis of the body detected by the single axis acceleration sensor, walking with a simple configuration as compared with the case of using the acceleration in the three axis direction. Operation can be determined.

  According to the eleventh aspect of the present invention, the smoothness of the walking motion can be determined based on the degree of change from the previous measurement by using the value calculated from the measurement waveform of the subject as the reference value.

  According to the invention of claim 12, by informing the subject of the determination result regarding the left / right balance of the walking motion, the subject can be prompted to improve the walking motion or confirm the change of the walking motion.

(Embodiment 1)
First, the configuration of the walking motion analyzer of Embodiment 1 will be described. As shown in FIG. 1, this walking motion analysis device is equipped with a sensor unit 1 that detects acceleration in a single axis direction other than the left and right axes of a body part that is attached to the body and is caused by walking, and a detection result of the sensor unit 1. A signal generation circuit unit 2 that generates an acceleration waveform; an arithmetic processing unit 3 that extracts a feature amount of the acceleration waveform generated by the signal generation circuit unit 2 to determine walking motion; a storage unit 4 that stores data; An input unit 5 for a user to turn on and off the power supply and an output unit 6 for outputting various information are provided.

  The sensor unit 1 is a uniaxial acceleration sensor that outputs, as a voltage value, an acceleration signal from a piezoresistor whose resistance value changes according to the acting acceleration. The uniaxial acceleration sensor may have any other principle such as a capacitance type or a heat detection type.

  The acceleration sensor, which is the sensor unit 1, is mounted mainly at the center of the back and back near the center of gravity of the body, but the mounting location may be arbitrary as long as the left-right symmetry can be analyzed on the midline of the body. In addition, as a method for mounting the acceleration sensor which is the sensor unit 1, there are a method in which a clip attached to the acceleration sensor is fastened to a waist belt or pants, or a supporter for fixing the acceleration sensor is wound around the waist.

  Some acceleration sensors are equipped with a memory that stores measurement data in the main body, and others are equipped with a wireless module that can measure in real time in conjunction with a personal computer. When measuring in real time in cooperation with a personal computer, a device that enables wireless transmission without using a cable or the like is preferable so as not to hinder the walking motion. In this case, since the subject can freely walk without being aware that the measurement is being performed, measurement that is not affected by the subject's consciousness is possible. After wearing the acceleration sensor, the test subject naturally walks straight in the usual way of walking. The measurement place is preferably a place where a flat straight section can be secured.

  The signal generation circuit unit 2 is a circuit that is connected to the sensor unit 1, converts an analog voltage value of acceleration detected by the sensor unit 1 into a digital voltage value, and converts it into data that can be processed by the arithmetic processing unit 3. The signal generation circuit section 2 includes a filter 20 that filters an analog signal and an analog / digital conversion circuit (A / D in FIG. 1) 21 that converts the analog signal into a digital signal. The signal generation circuit unit 2 only needs to be able to compare the characteristics of the acceleration waveform such as the maximum and minimum values of the amplitude of the acceleration waveform in the arithmetic processing unit 3. For example, a low-pass filter of 100 Hz with a sampling frequency of 200 Hz The acceleration waveform signal that has been passed and analog / digital converted is output to the arithmetic processing unit 3.

  The storage unit 4 includes a measurement waveform storage unit 40 that stores the acceleration waveform detected by the sensor unit 1 and generated by the signal generation circuit unit 2. The storage unit 4 includes, for example, a volatile storage element such as a RAM serving as a so-called working memory of the arithmetic processing unit 3 and a non-volatile storage element such as a ROM. The measured waveform once stored in the storage unit 4 is output to the arithmetic processing unit 3.

  The arithmetic processing unit 3 includes, for example, a microprocessor and its peripheral devices, and compares the feature amount of the acceleration waveform in one walking cycle with the waveform analysis unit 30 that extracts the feature amount from the acceleration waveform from the signal generation circuit unit 2. The comparison part 31 and the walking state determination part 32 which analyzes left-right symmetry based on the comparison result of the comparison part 31 are provided.

  Note that the acceleration waveform of this embodiment alone cannot determine which is caused by the movement of the left or right leg, and since it is not known which side is biased to the left or right, it is determined only that there is a difference in left-right symmetry.

  As a sensor for determining whether the characteristic of the acceleration waveform is caused by the movement of the left or right leg, for example, there is a sensor equipped with a foot switch and mounted on the left and right soles of the subject. Thereby, it can be specified whether it is biased to right or left.

  Here, an arithmetic processing method by the arithmetic processing unit 3 of the present embodiment will be described. This embodiment demonstrates the case where the sensor part 1 is mounted | worn with a body so that the single axis direction of the sensor part 1 may turn into a vertical axis direction. FIG. 2 is an acceleration waveform in the vertical axis direction in one walking cycle when the acceleration sensor as the sensor unit 1 is attached to the lower back. In FIG. 2, one walking cycle is about 1 second, and the right leg stands upright from the initial grounding during 0-0.5 seconds, and takes off from the standing leg, and between 0.5 seconds-1 second. The left leg is standing from the initial grounding, and the leg is off from the standing leg. Therefore, in order to compare the walking motion of the right leg and the left leg, the acceleration waveform between 0 and 0.5 seconds may be compared with the acceleration waveform between 0.5 seconds and 1 second.

  Although there is a difference in the amplitude level of the acceleration waveform between subjects, the waveform pattern as shown in FIG. 2 is similar between subjects in the acceleration waveform in the vertical axis direction, so the appearance of features such as the maximum value and minimum value of the acceleration waveform appears. It is possible to specify two consecutive stance periods corresponding to the movement of the left and right legs at the timing.

  FIG. 3 shows an acceleration waveform in the vertical axis direction in one walking cycle. In FIG. 3 (a), the maximum value RA1 in the right leg motion and the maximum value LA1 in the left leg motion are compared in two successive stance phase acceleration waveforms corresponding to the left and right leg motions. As a comparison method, a value S1 = LA1−RA1 which is a difference between the maximum value RA1 and the maximum value LA1, a value S2 = LA1 / RA1 which is a ratio between the maximum value RA1 and the maximum value LA1, and a value S3 = (LA1−RA1). / (LA1 + RA1).

  When the value S1 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S1 is closer to zero. When the value S2 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S2 is closer to 1. When the value S3 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S3 is closer to zero. Moreover, since the value S3 represents the ratio of the left-right difference of the acceleration in the upward direction, the calculated result can be compared within the same subject when the stride or walking speed is changed, or between different subjects. Can be used for comparison. Note that the comparison method is not limited to the values S1, S2, and S3 as long as the difference between the maximum value RA1 and the maximum value LA1 can be compared.

  Further, as shown in FIG. 4A, the arithmetic processing unit 3 counts the number of times the peak of the acceleration signal is generated by counting the intersection of the acceleration waveform and the threshold value. Thereby, the arithmetic processing unit 3 can measure the number of steps.

  The arithmetic processing unit 3 can determine the stride by second-order integrating the acceleration waveform. In addition to the above, the method for obtaining the stride is to obtain the stride corresponding to the walking pitch obtained from the acceleration waveform using a table showing the relationship between the walking pitch and the stride, as shown in FIG. 4B. Can do. Note that the amplitude of the acceleration waveform may be used instead of the walking pitch.

  Using the number of steps and the step length obtained as described above, the arithmetic processing unit 3 can obtain the value from (walking distance) = (step number) × (step length).

  The walking speed can be calculated from (walking speed) = (step length) / (required time per step), (walking speed) = (walking distance) / (required time).

  The input unit 5 shown in FIG. 1 gives instructions to the walking state analysis device such as a power switch for turning on / off the power of the walking state analysis device, a calculation processing start switch for instructing start of calculation processing of acceleration waveforms, and a timer. Various switches are provided.

  The output unit 6 is, for example, a display device such as a CRT display or a sound output device such as a speaker, and outputs the walking motion determination result determined by the arithmetic processing unit 3. The walking motion determination result may be confirmed by the subject after the walking motion, or may be notified in real time from the speaker by voice or the like while the subject is walking.

  As described above, according to the present embodiment, by using acceleration in a single axis direction other than the left and right axes of the body detected by the uniaxial acceleration sensor, walking with a simple configuration as compared with the case of using acceleration in the three axis direction. The left / right balance of the operation can be determined.

  In addition, according to the present embodiment, only the acceleration in the vertical axis direction necessary for calculating the walking parameters such as the number of steps, the walking distance, the walking speed, and the stride is detected, and the acceleration in the other axial direction is detected. The right and left balance of the walking motion can be determined together with the walking parameters such as the number of steps, the walking distance, the walking speed, and the step length.

  Furthermore, according to the present embodiment, extreme values that can be extracted by simple signal processing from continuous acceleration waveform signals can be used as feature values of the acceleration waveform, so that the left-right balance of the walking motion can be more easily performed. Can be determined.

  According to the present embodiment, the subject can be prompted to improve the walking motion or confirm the change in the walking motion by notifying the subject of the determination result regarding the left-right balance of the walking motion.

  As a modification of the first embodiment, in FIG. 3B, in the acceleration waveforms in the two consecutive stance phases corresponding to the left and right leg movements, the minimum value RB1 in the right leg movement and the minimum in the left leg movement are shown. The value LB1 may be compared. As a comparison method, a value S4 = LB1-RB1 which is a difference between the minimum value RB1 and the minimum value LB1, a value S5 = LB1 / RB1 which is a ratio of the minimum value RB1 and the minimum value LB1, and a value S6 = (LB1-RB1). / (LB1 + RB1).

  When the value S4 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S4 is closer to zero. When the value S5 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S5 is closer to 1. When the value S6 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S6 is closer to zero. Moreover, since the value S6 represents the ratio of the left-right difference of the acceleration in the downward direction, the calculated result can be compared within the same subject when the stride or walking speed is changed, or between different subjects. Can be used for comparison. Note that the comparison method is not limited to the values S4, S5, and S6 as long as the difference between the minimum value RB1 and the minimum value LB1 can be compared.

(Embodiment 2)
As shown in FIG. 5, the walking motion analysis apparatus according to the second embodiment is a walking motion analysis according to the first embodiment in that the arithmetic processing unit 3 extracts the magnitude of the maximum amplitude of the acceleration waveform as the feature amount of the acceleration waveform. Different from the device. In addition, about the component similar to Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  FIG. 5 compares the maximum vertical amplitude RC1 in the right leg motion with the maximum vertical amplitude LC1 in the left leg motion in two consecutive stance phase acceleration waveforms corresponding to the left and right leg motions. As a comparison method, a value S7 = LC1-RC1 which is a difference between the maximum amplitude RC1 and the maximum amplitude LC1, a value S8 = LC1 / RC1 which is a ratio between the maximum amplitude RC1 and the maximum amplitude LC1, and a value S9 = (LC1-RC1). / (LC1 + RC1).

  When the value S7 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S7 is closer to zero. When the value S8 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S8 is closer to 1. When the value S9 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S9 is closer to zero. Moreover, since the value S9 represents the ratio of the left-right difference of the acceleration in the vertical direction, the calculated result can be compared within the same subject when the stride or walking speed is changed, or between different subjects. Can be used for comparison. Note that the comparison method is not limited to the values S7, S8, and S9 as long as the difference between the maximum amplitude RC1 and the maximum amplitude LC1 can be compared.

  As described above, according to the present embodiment, by using the maximum amplitude of the continuous acceleration waveform signal as the feature value of the acceleration waveform, analysis in both directions (vertical upward direction and vertical downward direction) can be performed at once in the same axis. The left / right balance of the walking motion can be determined in detail.

(Embodiment 3)
As shown in FIG. 6A, the walking motion analysis apparatus according to the third embodiment is implemented in that the arithmetic processing unit 3 extracts an area surrounded by the acceleration waveform and the time axis as a feature amount of the acceleration waveform. This is different from the walking motion analysis apparatus according to the first embodiment. In addition, about the component similar to Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  FIG. 6 shows an acceleration waveform in the vertical axis direction in one walking cycle. In FIG. 6A, the area RD1 in the right leg movement and the area LD1 in the left leg movement are compared in the acceleration waveforms in the two stance phases corresponding to the left and right leg movements. As a comparison method, a value S10 = LD1−RD1 which is a difference between the area RD1 and the area LD1, a value S11 = LD1 / RD1 which is a ratio of the area RD1 and the area LD1, and a value S12 = (LD1−RD1) / (LD1 + RD1). and so on.

  When the value S10 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S10 is closer to zero. When the value S11 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S11 is closer to 1. When the value S12 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S12 is closer to zero. Moreover, since the value S12 represents the ratio of the left-right difference of the acceleration in the upward direction, the calculated result can be compared within the same subject when the stride or walking speed is changed, or between different subjects. Can be used for comparison. Note that the comparison method is not limited to the values S10, S11, and S12 as long as the difference between the area RD1 and the area LD1 can be compared.

  As described above, according to the present embodiment, by using the area calculated from the continuous waveform signal and the time axis as the feature amount of the acceleration waveform, the analysis using the index reflecting the entire movement of the left and right legs in the walking cycle can be performed. And the left-right balance of the walking motion can be determined in more detail.

  As a modification of the third embodiment, in FIG. 6B, in two consecutive stance phase acceleration waveforms corresponding to the left and right leg movements, the area RE1 for the right leg movement and the area LE1 for the left leg movement are shown. And compare. As a comparison method, a value S13 = LE1-RE1 which is a difference between the area RE1 and the area LE1, a value S14 = LE1 / RE1 which is a ratio between the area RE1 and the area LE1, and a value S15 = (LE1−RE1) / (LE1 + RE1). and so on.

  When the value S13 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S13 is closer to zero. When the value S14 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S14 is closer to 1. When the value S15 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S15 is closer to zero. Moreover, since the value S15 represents the ratio of the left-right difference of the acceleration in the downward direction, the calculated result can be compared within the same subject when the stride or walking speed is changed, or between different subjects. Can be used for comparison. Note that the comparison method is not limited to the values S13, S14, and S15 as long as the difference between the area RE1 and the area LE1 can be compared.

  As another modification of the third embodiment, in FIG. 6C, in two consecutive stance phases corresponding to the left and right leg movements, the area RF1 in the right leg movement and the area in the left leg movement are shown. Compare with LF1. As a comparison method, a value S16 = LF1−RF1 which is a difference between the area RF1 and the area LF1, a value S17 = LF1 / RF1 which is a ratio of the area RF1 and the area LF1, and a value S18 = (LF1−RF1) / (LF1 + RF1). and so on.

  When the value S16 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S16 is closer to zero. When the value S17 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S17 is closer to 1. When the value S18 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S18 is closer to zero. Moreover, since the value S18 represents the ratio of the left-right difference in the vertical acceleration, the calculated result can be compared within the same subject when the stride or walking speed is changed, or between different subjects. Can be used for comparison. Note that the comparison method is not limited to the values S16, S17, and S18 as long as the difference between the area RF1 and the area LF1 can be compared.

(Embodiment 4)
In the walking motion analysis apparatus of the fourth embodiment, the arithmetic processing unit 3 causes the stance phase acceleration waveform amplitude value corresponding to the left leg motion in the walking cycle and the stance phase acceleration waveform amplitude value corresponding to the right leg motion. Is different from the walking motion analyzer of the first embodiment in that it is compared using a correlation function. In addition, about the component similar to Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The arithmetic processing unit 3 of this embodiment extracts the amplitude value of the acceleration waveform for each unit time as the feature amount of the acceleration waveform as shown in FIG. 7, and the acceleration waveform in the stance phase corresponding to the movement of the left leg in the walking cycle. Is compared with the amplitude value of the acceleration waveform in the stance phase corresponding to the motion of the right leg by using a correlation function to determine whether the left-right balance of the walking motion is normal.

  In this embodiment, the cross-correlation function Fc shown in Equation 1 is calculated.

  In Equation 1, XTi is a value at the i-th sampling time point in the acceleration waveform L at time t12 to t14 in FIG. 7, and Xi + p is an i + p-th sampling time value in the acceleration waveform R at time 0 to t12 in FIG. Value. n is the total number of samplings in the acceleration waveform L. p is an integer value of 0 or more.

  As described above, according to the present embodiment, by using the correlation function between the acceleration waveform in the left leg motion and the acceleration waveform in the right leg motion, the entire left and right leg motion in the walking cycle can be performed every unit time based on the sampling frequency. Analysis can be performed, and the left-right balance of the walking motion can be determined in more detail.

  As a modification of the fourth embodiment, a function Fe (Expression 2) that is a mean square of the difference between the acceleration waveform R and the acceleration waveform L may be used.

  In Equation 2, XTi is a value at the i-th sampling time point in the acceleration waveform L at times t12 to t14 in FIG. 7, and Xi + p is an i + p-th sampling time value in the acceleration waveform R at time 0 to t12 in FIG. Value. n is the total number of samplings in the acceleration waveform L. p is an integer value of 0 or more.

(Embodiment 5)
As shown in FIG. 8A, the walking motion analysis apparatus according to the fifth embodiment is different from the walking motion analysis apparatus according to the first embodiment in that the left / right balance in the acceleration waveform in the vertical axis direction in three walking cycles is compared. To do. In addition, about the component similar to Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The arithmetic processing unit 3 according to the present embodiment compares left and right symmetry within a continuous time by alternately averaging and comparing features such as maximum and minimum values of acceleration waveforms in a plurality of continuous walking cycles. analyse.

  In FIG. 8 (a), in the acceleration waveform of two consecutive stance phases corresponding to the movements of the left and right legs, the average maximum value RAx that is the average value of the maximum values RA1, RA2, and RA3 and the maximum values LA1, LA2, and LA3. The average maximum value LAx which is an average value is compared. As a comparison method, a value S19 = LAx−RAx which is a difference between the average maximum value RAx and the average maximum value LAx, a value S20 = LAx / RAx which is a ratio between the average maximum value RAx and the average maximum value LAx, a value S21 = ( LAx−RAx) / (LAx + RAx). However, LAx = (LA1 + LA2 + LA3) / 3, and RAx = (RA1 + RA2 + RA3) / 3.

  When the value S19 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S19 is closer to zero. When the value S20 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S20 is closer to 1. When the value S21 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S21 is closer to zero. Moreover, since the value S21 represents the ratio of the left-right difference of the acceleration in the upward direction, the calculated result can be compared within the same subject when the stride or walking speed is changed, or between different subjects. Can be used for comparison. Note that the method of comparison is not limited to the values S19, S20, and S21 as long as the difference between the average maximum value RAx and the average maximum value LAx can be compared.

  In addition, although the example of 3 walk cycles was shown in Embodiment 5, you may compare in many walk cycles.

  Further, as a modification of the fifth embodiment, in FIG. 8B, in the acceleration waveform of two consecutive stance phases corresponding to the movement of the left and right legs, an average minimum value that is an average value of the minimum values RB1, RB2, and RB3. RBx is compared with the average minimum value LBx that is the average value of the minimum values LB1, LB2, and LB3. As a comparison method, a value S22 = LBx−RBx which is a difference between the average minimum value RBx and the average minimum value LBx, a value S23 = LBx / RBx which is a ratio of the average minimum value RBx and the average minimum value LBx, a value S24 = ( LBx−RBx) / (LBx + RBx). However, LBx = (LB1 + LB2 + LB3) / 3, and RBx = (RB1 + RB2 + RB3) / 3.

  When the value S22 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S22 is closer to zero. When the value S23 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S23 is closer to 1. When the value S24 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S24 is closer to zero. In addition, since the value S24 represents the ratio of the left-right difference in the acceleration in the downward direction, the calculated result can be compared within the same subject when the stride or walking speed is changed, or between different subjects. Can be used for comparison. The comparison method is not limited to the values S22, S23, and S24 as long as the difference between the average minimum value RBx and the average minimum value LBx can be compared.

  Furthermore, as another modified example of the fifth embodiment, in FIG. 8C, in the waveform of two consecutive stance phases corresponding to the movement of the left and right legs, the average maximum that is the average value of the maximum amplitudes RC1, RC2, and RC3. The amplitude RCx is compared with the average maximum amplitude LCx that is the average value of the maximum amplitudes LC1, LC2, and LC3. As a comparison method, a value S25 = LCx−RCx which is a difference between the average maximum amplitude RCx and the average maximum amplitude LCx, a value S26 = LCx / RCx which is a ratio of the average maximum amplitude RCx and the average maximum amplitude LCx, and a value S27 = ( LCx−RCx) / (LCx + RCx). However, LCx = (LC1 + LC2 + LC3) / 3 and RCx = (RC1 + RC2 + RC3) / 3.

  When the value S25 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S25 is closer to zero. When the value S26 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S26 is closer to 1. When the value S27 is used, the arithmetic processing unit 3 determines that the left-right balance is better as the value S27 is closer to zero. In addition, since the value S27 represents the ratio of the left-right difference in the vertical acceleration, the calculated result can be compared within the same subject when the stride or walking speed is changed, or between different subjects. Can be used for comparison. Note that the method of comparison is not limited to the values S25, S26, and S27 as long as the difference between the average maximum amplitude RCx and the average maximum amplitude LCx can be compared.

(Embodiment 6)
In the walking motion analysis apparatus according to the sixth embodiment, the storage unit 4 illustrated in FIG. 1 includes a reference waveform storage unit 41 that stores in advance the characteristic amount of the reference waveform of the acceleration waveform, and the arithmetic processing unit 3 detects the sensor unit 1. This is different from the walking motion analysis apparatus of the first embodiment in that the feature amount of the acceleration waveform generated from the result is compared with the feature amount of the reference waveform stored in the storage unit 4. In addition, about the component similar to Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The reference waveform stored in the storage unit 4 is an acceleration waveform detected in advance by the sensor unit 1.

  The arithmetic processing unit 3 according to the present embodiment determines whether or not the left-right balance of the walking motion is normal by performing the comparison.

  As described above, according to the present embodiment, by comparing the feature amount of the acceleration waveform generated from the detection result with the feature amount of the reference waveform, the right and left of the walking motion is determined based on the difference from the reference time (during normal walking). Balance can be determined.

  In addition, according to the present embodiment, by using the measurement waveform of the subject himself / herself as the reference waveform, the left / right balance of the walking motion can be determined based on the degree of change of the subject himself / herself since the previous measurement.

(Embodiment 7)
As shown in FIG. 9, in the walking motion analysis apparatus according to the seventh embodiment, the storage unit 4 includes a reference value storage unit 42 that stores in advance a reference value of a feature value of an acceleration waveform, and the arithmetic processing unit 3 includes a sensor unit. 1 is different from the walking motion analysis apparatus according to the first embodiment in that the feature value of the acceleration waveform generated from the detection result 1 is compared with the reference value (including the reference range) stored in the storage unit 4. In addition, about the component similar to Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  The reference value stored in the storage unit 4 is a value calculated from the acceleration waveform detected in advance by the sensor unit 1.

  The arithmetic processing unit 3 of the present embodiment determines the smoothness of the walking motion by performing the comparison.

  In FIG. 9A, the maximum value Max of the acceleration waveform in the vertical axis direction detected by the sensor unit 1 falls within the reference range (AB) of the amplitude of the acceleration waveform provided in advance upward with respect to the vertical axis direction. Indicates that it is in. FIG. 9B shows that the maximum value Max does not fall within the reference range (A-B) of the amplitude of the acceleration waveform provided in advance upward with respect to the vertical axis direction.

  When walking naturally, the vertical movement of the body occurs in the vertical axis direction. This means that when walking on two legs, the left and right legs move upwards with respect to the vertical line from both leg support to single leg support, and the upper body with respect to the vertical line from single leg support to both leg support. This is because is moved downward. For this reason, although the minimum acceleration is generated with the vertical movement, if there is an excessive vertical movement more than necessary, it cannot be said to be a smooth walking movement. For this reason, the arithmetic processing unit 3 determines that the user can walk smoothly if the maximum value Max is within the reference range (AB).

  In FIG. 9C, the minimum value Min of the acceleration waveform in the vertical axis direction detected by the sensor unit 1 falls within the reference range (C−D) of the amplitude of the acceleration waveform provided in advance downward with respect to the vertical axis direction. Indicates that it is in. In FIG. 9D, the maximum value Max and the minimum value Min of the acceleration waveform in the vertical axis direction detected by the sensor unit 1 are the amplitudes of the acceleration waveform previously provided in both the upward and downward directions with respect to the vertical axis direction. It shows that it is in the reference range (A-B) and the reference range (C-D).

  As a range of acceleration determined to be smooth, for example, gravitational acceleration is subtracted, and the upward direction is in the range of 0.2G to 1G, and the downward direction is in the range of -0.2G to -1G.

  As described above, according to the present embodiment, by using the acceleration in the single axis direction other than the left and right axes of the body detected by the sensor unit 1, the walking motion can be performed with a simple configuration as compared with the case of using the acceleration in the three axis direction. Smoothness can be determined.

  Further, according to the present embodiment, the smoothness of the walking motion can be determined based on the degree of change from the previous measurement by using the value calculated from the measurement waveform of the subject as the reference value.

  In the seventh embodiment, the extreme value (maximum value or minimal value) of the acceleration waveform is used as the feature value of the acceleration waveform. However, although not shown, the feature value of the acceleration waveform when determining smoothness is not shown. Alternatively, the maximum amplitude, area, calculated value of the correlation function, or the like may be used.

  In the seventh embodiment, the acceleration waveform detected by the sensor 1 is analyzed and it is determined that the left / right balance is good, and the amplitude of the acceleration waveform is compared with the reference value by the above-described method to determine smoothness. And However, only smoothness can be determined without determining the left-right balance.

(Embodiment 8)
The walking motion analysis apparatus of the eighth embodiment is different from the walking motion analysis apparatus of the first embodiment in that the single axis direction of the sensor unit 1 is a traveling axis direction that is a direction in which the body walks. In addition, about the component similar to Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  FIG. 10 is an example of an acceleration waveform in the direction of the advancing axis in one walking cycle when the acceleration sensor as the sensor unit 1 is attached to the lower back. In FIG. 10, one walking cycle is about 1 second, and the right leg is standing from the initial grounding, and the foot is separated from the standing leg during 0 to 0.5 seconds, and between 0.5 seconds and 1 second. The left leg is standing from the initial grounding, and the leg is off from the standing leg. Therefore, in order to compare the walking motion of the right leg and the left leg, the acceleration waveform between 0 and 0.5 seconds may be compared with the acceleration waveform between 0.5 seconds and 1 second.

  As described above, also in the present embodiment, as in the case where the single axis direction of the sensor unit 1 is the vertical axis direction, the traveling axis direction necessary for calculating the walking parameters such as the number of steps, the walking distance, the walking speed, and the step length The left and right balance of the walking motion can be determined together with the walking parameters such as the number of steps, the walking distance, the walking speed, and the step length, without detecting the acceleration in the other axial direction.

(Embodiment 9)
As illustrated in FIG. 11, the walking motion analysis device of the ninth embodiment is different from the walking motion analysis device of the seventh embodiment in that the smoothness in the acceleration waveform in the traveling axis direction in one walking cycle is compared. In addition, about the component similar to Embodiment 7, the same code | symbol is attached | subjected and description is abbreviate | omitted.

  In FIG. 11A, the maximum value Max of the acceleration waveform in the traveling axis direction detected by the sensor unit 1 does not exceed the reference value A of the amplitude of the acceleration waveform previously provided in the forward direction with respect to the traveling axis direction. Indicates. FIG. 11B shows that the maximum value Max exceeds the reference value A of the amplitude of the acceleration waveform previously provided in the forward direction with respect to the traveling axis direction.

  When walking naturally, the acceleration is zero if it is a constant velocity motion in the direction of the traveling axis, so the acceleration decreases when walking more smoothly in the direction of the traveling axis. For this reason, if the maximum value Max does not exceed the reference value A, the arithmetic processing unit 3 determines that the user can walk smoothly.

  In FIG. 11C, the minimum value Min of the acceleration waveform in the traveling axis direction detected by the sensor unit 1 does not exceed the reference value B of the amplitude of the acceleration waveform provided in the rearward direction with respect to the traveling axis direction. Indicates. In FIG. 11D, the maximum value Max and the minimum value Min of the acceleration waveform in the traveling axis direction detected by the sensor unit 1 are the amplitudes of the acceleration waveform previously provided in both the forward direction and the backward direction with respect to the traveling axis direction. The reference values A and B are not exceeded.

  For smooth walking motion, the smaller the acceleration, the better. However, the acceleration determined to be smooth is, for example, 0.5G or less for the forward direction and −0.5G or more for the backward direction.

  In the ninth embodiment, the extreme value (maximum value or minimal value) of the acceleration waveform is used as the feature value of the acceleration waveform. However, although not shown, the feature value of the acceleration waveform when determining smoothness is not shown. Alternatively, the maximum amplitude, area, calculated value of the correlation function, or the like may be used.

  In the first to ninth embodiments, it is mainly used for determination of walking motion, but as a modified example of the first to ninth embodiments, the right and left balance and smoothness are determined by the same method during running other than walking. Shall be able to.

It is a block diagram which shows the structure of the walking movement analyzer based on Embodiment 1. FIG. It is a figure which shows the acceleration waveform of the vertical-axis direction in 1 walk cycle. In Embodiment 1, it is a figure explaining the left-right balance comparison in the acceleration waveform of a perpendicular axis direction. It is a figure explaining how to obtain | require the number of steps and step length in the same as the above. In Embodiment 2, it is a figure explaining the left-right balance comparison in the acceleration waveform of a vertical-axis direction. In Embodiment 3, it is a figure explaining the left-right balance comparison in the acceleration waveform of a vertical-axis direction. In Embodiment 4, it is a figure explaining the left-right balance comparison in the acceleration waveform of a perpendicular axis direction. In Embodiment 5, it is a figure explaining the left-right balance comparison in the acceleration waveform of a perpendicular axis direction. In Embodiment 7, it is a figure explaining the smoothness comparison in the acceleration waveform of a vertical-axis direction. It is a figure which shows the acceleration waveform of the advancing axis direction in 1 walk cycle. In Embodiment 9, it is a figure explaining the smoothness comparison in the acceleration waveform of the advancing axis direction.

Explanation of symbols

1 Sensor unit 3 Arithmetic processing unit 4 Storage unit

Claims (12)

A one-axis acceleration sensor that detects acceleration in a single axis direction other than the left-right axis direction of a body part that is attached to the body and is caused by walking;
The feature amount of the acceleration waveform generated from the detection result of the one-axis acceleration sensor is extracted, and the right and left balance of the walking motion is adjusted by using the feature amount of the acceleration waveform in the stance phase corresponding to the motion of the left and right legs in the walking cycle. A walking motion analyzer comprising: an arithmetic processing unit that determines whether or not it is normal.   The walking motion analysis apparatus according to claim 1, wherein the uniaxial acceleration sensor is attached to the body such that the single axis direction is a vertical axis direction.   The walking motion analysis apparatus according to claim 1, wherein the uniaxial acceleration sensor is attached to the body such that the single axis direction is a traveling axis direction in which the body walks.   The walking motion analysis apparatus according to any one of claims 1 to 3, wherein the arithmetic processing unit extracts an extreme value of an acceleration waveform as a feature amount of the acceleration waveform.   The walking operation analysis apparatus according to any one of claims 1 to 3, wherein the arithmetic processing unit extracts a magnitude of a maximum amplitude of the acceleration waveform as a feature amount of the acceleration waveform.   4. The walking motion analysis apparatus according to claim 1, wherein the arithmetic processing unit extracts an area surrounded by an acceleration waveform and a time axis as a feature amount of the acceleration waveform. 5.   The arithmetic processing unit uses a correlation function between the acceleration waveform in the stance phase corresponding to the left leg motion in the walking cycle and the acceleration waveform in the stance phase corresponding to the right leg motion, and the right and left balance of the walking motion is normal. The walking motion analysis apparatus according to any one of claims 1 to 3, wherein it is determined whether or not there is any. A storage unit that stores in advance the feature amount of the reference waveform of the acceleration waveform,
The arithmetic processing unit compares the feature amount of the acceleration waveform generated from the detection result of the uniaxial acceleration sensor with the feature amount of the reference waveform stored in the storage unit, thereby achieving a right / left balance of the walking motion. It is determined whether it is normal. The walking movement analyzer of any one of Claims 1 thru | or 7 characterized by the above-mentioned.   The walking motion analysis apparatus according to claim 8, wherein the reference waveform stored in the storage unit is an acceleration waveform detected in advance by the uniaxial acceleration sensor. A storage unit that stores in advance a reference value of the feature value of the acceleration waveform;
The arithmetic processing unit determines a walking motion by comparing a feature amount of an acceleration waveform generated from a detection result of the uniaxial acceleration sensor and a reference value stored in the storage unit. The walking motion analyzer according to any one of claims 1 to 9.   The walking motion analysis apparatus according to claim 10, wherein the reference value stored in the storage unit is a value calculated from an acceleration waveform detected in advance by the uniaxial acceleration sensor.   The walking motion analysis apparatus according to any one of claims 1 to 11, further comprising an output unit that outputs a walking motion determination result determined by the arithmetic processing unit.

Images