JP2009125506A - Walking figure improvement support system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a walking figure improvement support system which facilitates the improving of walking figures considering muscular forces of feet of a user. <P>SOLUTION: The system includes: attitude angle detection parts 10<SB>L</SB>and 10<SB>R</SB>for measuring accelerations and directions of thigh parts of the user making walking actions; attitude angle detection parts 20<SB>L</SB>and 30<SB>R</SB>for measuring accelerations and directions of ankles, pressure sensors 40<SB>L</SB>and 40<SB>R</SB>for measuring reactions from the ground surface working on soles; a muscular force estimation part 602 for estimating the balance of the muscular forces of feet from the accelerations, directions and forces measured; an improvement information generation part 603 which generates image information for improving walking figures of the user from the muscular force balance of the feet estimated; and a head-mounted display 70 for outputting the image information generated by the improvement information generation part 603. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a gait improvement support system for improving a user's gait.

2. Description of the Related Art Conventionally, there is a walking motion detection processing device that attaches an accelerometer to or around a user's waist, detects an acceleration vector together with an angular velocity vector of a walking motion, and detects a gait based on these data (for example, Patent Document 1).
JP 2005-114537 A

  However, with the conventional technology, the user's gait can be detected, but there is no configuration for improving the gait, and the user needs to consider an improvement method by himself, and the improvement of the gait is not easy. It was. Furthermore, the detected gait did not consider the muscle strength of the user's foot.

  In addition, as a technique to know the activity state of muscles, it is conceivable to measure myoelectricity, but in order to measure the potential difference generated during muscle contraction, it is necessary to directly attach the sensor electrode to the user of the exercise assisting device There is a problem that it cannot be used easily. In particular, in order to accurately measure myoelectricity, specialized knowledge is required at the position where the electrode is attached. Therefore, such a method for measuring muscle strength using an electromyogram could not be employed in a general walking improvement system due to the above problem.

  The present invention has been made in view of the above reasons, and an object thereof is to provide a gait improvement support system capable of easily improving gait in consideration of muscle strength of a user's foot. .

  According to the first aspect of the present invention, there is provided a measuring means for measuring the acceleration and direction of a predetermined part of a user's foot performing a walking motion and a reaction force from the ground applied to the sole, and the measured acceleration, direction and force. Based on the muscle strength estimating means for estimating the strength balance of the foot based on, the improvement information generating means for generating information for improving the gait of the user based on the estimated strength balance of the foot, and the improvement information generating means And an improved information presenting means for presenting information.

  According to the present invention, the gait can be easily improved based on the muscular strength balance of the user's foot.

  The “walk” in the present invention includes running such as jogging and running in addition to walking and walking.

  According to a second aspect of the present invention, in the first aspect, the measuring means includes a predetermined part of the user's foot by means of an acceleration sensor having two or more axes and a gyro sensor having one or more axes attached to the predetermined part of the user's foot It is characterized by measuring the acceleration and direction.

  According to this invention, the acceleration of a predetermined part of the user's foot can be accurately measured.

  According to a third aspect of the present invention, in the first aspect, the measurement unit is configured to detect a predetermined part of the user's foot by using a biaxial or more acceleration sensor and a three-axis geomagnetic sensor attached to the predetermined part of the user's foot. It is characterized by measuring acceleration and direction.

  According to this invention, the acceleration of a predetermined part of the user's foot can be accurately measured.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the measuring means is a user using a pressure sensor provided on a shoe sole worn by the user or an acceleration sensor mounted on the ankle of the user. It measures the reaction force from the ground applied to the sole of the foot.

  According to this invention, the reaction force from the ground applied to the user's sole can be accurately measured.

  As described above, the present invention has an effect that the gait can be easily improved in consideration of the muscle strength of the user's foot.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment)
As shown in FIG. 2, the gait improvement support system of the present embodiment includes posture angle detection units 10 _L and 10 _R and a wireless transmission unit 30 mounted on the left and right thighs of the user H, respectively. _L, 30 _R and each mounting attitude angle detection unit ₂₀ to the left ankle and right ankle L, 20 _R and, Hidarikutsu _{S L} user H is worn, the right shoe _S each inner sole _S1 L of _R, It comprises pressure sensors 40 _L and 40 _R provided in S1 _R , wireless transmitters 50 _L and 50 _R , a controller 60 attached to the waist, and a head mounted display 70 attached to the head of the user H. The gait of the user H is analyzed and improved.

FIG. 1 shows a block configuration of this system. The posture angle detection unit 10 _L includes a biaxial acceleration sensor 11 _L and a single axis gyro sensor 12 _L, and the posture angle detection unit 10 _R includes a biaxial acceleration sensor. 11 _R and the uniaxial gyro sensor 12 _R, and the posture angle detection unit 20 _L includes a biaxial acceleration sensor 21 _L and a uniaxial gyro sensor 22 _{L. The} posture angle detection unit 20 _R includes two It comprises an axial acceleration sensor 21 _R and a uniaxial gyro sensor 22 _R. The acceleration sensors 11 _L and 11 _R and the gyro sensors 12 _L and 12 _R detect acceleration data and angular velocity data based on the movements of the left and right thighs of the user H during walking, respectively, and the acceleration sensors 21 _L and 21 _{The R} and gyro sensors 22 _L and 22 _R detect acceleration data and angular velocity data based on movements of the left and right ankles of the user H during walking, respectively. The acceleration data and the angular velocity data are two-axis acceleration data in the front-rear direction and the up-down direction when the user H standing in the up-down direction is walking in the front direction, with the left-right direction as an axis. This is uniaxial angular velocity data (data indicating the front and back, front and back directions of the thigh and ankle).

The wireless transmission unit 30 _L includes an operation power source such as a battery, and converts acceleration data and angular velocity data from the acceleration sensors 11 _L and 21 _L and the gyro sensors 12 _L and 22 _L received through the wiring into wireless signals. To the controller 60. The wireless transmission unit 30 _R includes an operation power source such as a battery, and converts acceleration data and angular velocity data from the acceleration sensors 11 _R and 21 _R and the gyro sensors 12 _R and 22 _R received via the wiring into wireless signals. To the controller 60.

The pressure sensors 40 _L and 40 _R are arranged to face the heel of the user H's sole, measure the ground pressure of the heel, and measure the ground pressure of the sole for each of the left and right feet. The pressure sensors 40 _L and 40 _R are of a piezoelectric type or a type using a resistance change due to pressure.

The wireless transmission units 50 _L and 50 _R are provided with an operating power source such as a battery. The wireless transmission unit 50 _L transmits the pressure data from the pressure sensor 40 _L to the controller 60 with a wireless signal, and the wireless transmission unit 50 _R The pressure data from the pressure sensor 40 _R is transmitted to the controller 60 by a wireless signal.

The controller 60 includes a microcomputer, a battery as an operation power supply, and the like. The thigh acceleration data and angular velocity data transmitted from the posture angle detectors 10 _L and 10 _R by radio signals, and posture angle detection. A wireless receiving unit 601 for receiving the ankle acceleration data and angular velocity data transmitted from the units 20 _L and 20 _R by wireless signals and the sole pressure data transmitted from the pressure sensors 40 _L and 40 _R by wireless signals; The muscle strength estimation unit 602 that estimates the strength balance of the foot based on the data received by the wireless reception unit 601 and the image information for improving the gait of the user H based on the estimated strength balance of the foot Improvement information generation unit 603 to improve, and improvement information to transmit the image information generated by the improvement information generation unit 603 to the head mounted display 70 via wiring A signal unit 604, and a manipulation unit 605 that performs the operation start and end and settings of each function.

  The head mounted display 70 includes a display unit 701 formed in a goggle type that covers the eyes of the user H, and displays image information for improving the gait on the display unit 701 to present to the user H.

  Next, the gait improvement of the user H by the gait improvement support system will be described.

First, the muscle strength estimation unit 602 of the controller 60 operates the operation unit 605 to operate the thigh acceleration data and angular velocity data waveforms transmitted from the posture angle detection units 10 _L and 10 _R , and the posture angle detection unit 20 _L. , 20 _R to analyze the waveform of the acceleration data and angular velocity data of the ankle, derive the posture change of the thigh and the posture change of the ankle, and identify the posture angle of the lower limb over time. Further, the waveform of the pressure data of the soles transmitted from the pressure sensors 40 _L and 40 _R is analyzed, and the reaction force Fa from the ground is identified over time.

  Next, the muscular strength estimation unit 602 models the lower limb of the user H with a link as shown in FIG. 3, sets a dynamic system model of the lower limb, and sets the joints (ankle joint P1, knee joint P2, hip joint P3) of the lower limbs. The joint moment Mi (see FIG. 5), which is a turning moment, is estimated as follows. Note that i = 1, 2, and 3, where 1 corresponds to the ankle joint P1, 2 to the knee joint P2, and 3 corresponds to the hip joint P3.

First, the mass mi, the mass center ratio ri, and the moment of inertia li in each link are expressed as follows. Note that i = 1, 2, and 3, where 1 is between the contact point P0 with the ground of the foot and the ankle joint P1, 2 is between the ankle joint P1 and the knee joint P2, and 3 is the knee joint P2. Corresponding to each link with the hip joint P3, bw is the weight of the user H, and these relations are described in “Okada et al .; Body part inertia characteristic of Japanese elderly”, Biomechanism 13 ”. ing.
m1 = 0.017bw
m2 = 0.047bw
m3 = 0.092bw
r1 = 58.1%
r2 = 42.3%
r3 = 48.1%
l1 = 32.6 (kg · cm ² )
l2 = 237.4 (kg · cm ² )
l3 = 495.1 (kg · cm ² )].

  On the other hand, considering the balance of forces in the link model as shown in FIGS. 4A, 4B, and 4C, the force x in the global coordinate system at each joint (ankle joint P1, knee joint P2, hip joint P3). The relationship of [Equation 1] is established among the direction component Fix, the y-direction component Fiy, and the joint moment Mi. It should be noted that i = 1, 2, 3 where 1 corresponds to the ankle joint P1, 2 corresponds to the knee joint P2, 3 corresponds to the hip joint P3, and g denotes the gravitational acceleration.

  Then, a muscle / skeletal model is set based on the joint moment Mi obtained as described above, and the magnitude of the force generated by each muscle of the lower limb is calculated. As shown in FIG. 5, the types of muscles are: gluteal muscle K1, biceps long head K2, gastrocnemius muscle K3, soleus muscle K4, iliopsoas muscle K5, rectus femoris muscle K6, medial vastus muscle K7, anterior tibia Nine muscle groups of muscle K8 and biceps femoris short head K9 are targeted. Now, the values shown in Table 1 are used, where Sj is the physiological cross-sectional area of the muscle Kj, and aij is the arm length (moment arm) around the joint Pi.

  However, the moment arm is assumed to be positive when the joint moment Mi acts in the direction shown in FIG. Assuming that the muscle contraction force is MFj, the equation of moment balance shown in [Equation 2] holds for each joint Pi.

  The muscle contraction speed vj is expressed by [Equation 3] using the moment arm aij and the joint angular speed wi.

By the way, it is known that the force that the muscle can exert varies depending on the physiological sectional area Sj, the contraction speed vj, and the length b. In this embodiment, the maximum muscle strength MFmaxj at each time is defined by [Equation 4]. ing. However, it is an isometric maximum contraction force represented by MFa = Sj · α, and α = 600000 N / mm ^{2 in} this embodiment.

By using the data described above, it is possible to calculate the force of each muscle for exerting the joint moment. Here, the unknown number is the number of muscles, that is, nine, whereas the balance formula to be satisfied is the number of joints, that is, three, so a solution cannot be obtained. Therefore, an optimization method is used to find a solution that minimizes the sum of the exerted muscle strength / maximum muscle strength of each muscle. That is,
Design variable Xj = MFj / MFmaxj
Constraints for minimizing the objective function f = ΣXj2:
Equality constraint: Mi = Σaij · MFj · Xj
Inequality constraint: 0 ≦ Xj ≦ 1
By obtaining the solution MFj under the constraint conditions described above, the muscle strength exerted at each time can be estimated, and the amount of muscle activity and the timing of the activity can be known.

Thus, to identify the occurrence of nine leg muscles strength MF ₁ ~MF ₉ for each of the left and right feet, guess strength balance of the foot.

  The improvement information generation unit 603 stores in advance image information that teaches improvement points with respect to various muscle strength balances (incorrect muscle strength balances) classified by attributes such as the height, weight, sex, and age of the user H. This image information is based on the teaching content suitable for the attribute of user H (how to use muscles to improve the deviation of the left and right center of gravity, how to use muscles that do not burden the joints of the legs, etc. How to use muscles to prevent pain). Then, based on the muscle strength balance of the foot estimated by the muscle strength estimation unit 602 and the attribute of the user H, image information that teaches the correct use of muscles for improving the gait is selected, and the image information is improved. The data is transmitted to the transmission unit 604.

  The improvement information transmission unit 604 transmits the image information generated by the improvement information generation unit 603 to the head mounted display 70 and causes the display unit 701 of the head mounted display 70 to display the image. The user H only needs to perform a walking motion with reference to an image that teaches the correct use of muscles suitable for his / her attributes, and considers the muscular strength of the user's feet (for example, the load on the left and right feet). (Moving habits, time difference between the right step time and left step time, difference between right step length and left step length, step distance, etc.) are easily improved.

Further, the improvement information transmission unit 604 is transmitted from the thigh acceleration data and angular velocity data transmitted from the posture angle detection units 10 _L and 10 _R and the posture angle detection units 20 _L and 20 _R by the operation of the operation unit 605. The image information obtained by converting the ankle acceleration data and angular velocity data and the pressure data of the soles transmitted from the pressure sensors 40 _L and 40 _R into a graph or the like is transmitted to the head mounted display 70. You can know the degree of gait improvement by looking at the data.

  Further, the inner sole S1 provided with the pressure sensor and the wireless transmission unit is mounted on the shoe, and the present system can be configured for a plurality of shoes and a plurality of users, so that the versatility of the system is enhanced.

Further, in the posture angle detection units 10 _L , 10 _R , 20 _L , and 20 _R , if the acceleration sensor has two or more axes and the gyro sensor has one or more axes, the muscle force estimation unit 602 can derive the posture angle of the lower limbs. Further, a triaxial geomagnetic sensor may be used instead of the gyro sensor.

Further, instead of the ground contact pressure measured by the pressure sensors 40 _L and 40 _R, from the ground applied to the sole using the acceleration due to the movement of the ankle measured by the acceleration sensors 21 _L and 21 _R provided on the ankle. It is also possible to obtain the reaction force Fa. In this case, the pressure sensors 40 _L and 40 _R and the wireless transmitters 50 _L and 50 _R are not necessary, and the system configuration can be simplified.

  It should be noted that “walking” in the above-described embodiment includes traveling such as jogging and running in addition to walking and walking.

It is a figure which shows the block configuration of the gait improvement assistance system of embodiment. It is a figure which shows the mounting state to the user same as the above. It is a figure which shows the link model of a lower limb same as the above. (A) (b) (c) It is explanatory drawing which shows the dynamical system model used in order to obtain | require a joint moment same as the above. It is a figure which shows a musculoskeletal model same as the above.

Explanation of symbols

10 _L , 10 _R attitude angle detection unit 20 _L , 20 _R attitude angle detection unit 30 _L , 30 _R wireless transmission unit 40 _L , 40 _R pressure sensor 50 _L , 50 _R wireless transmission unit 60 controller 601 wireless reception unit 602 muscle strength estimation Unit 603 improvement information generation unit 604 improvement information transmission unit 605 operation unit 70 head mounted display

Claims (4)

Measuring means for measuring the acceleration and direction of a predetermined part of a user's foot performing walking motion and the reaction force from the ground applied to the sole;
Muscle strength estimation means for estimating the strength balance of the foot based on the measured acceleration and direction and force;
Improvement information generating means for generating information for improving the gait of the user based on the estimated muscle strength balance of the foot;
A gait improvement support system comprising: improvement information presentation means for presenting information generated by the improvement information generation means.   The measuring means measures the acceleration and direction of a predetermined part of the user's foot with a two-axis or more acceleration sensor and a one-axis or more gyro sensor attached to the predetermined part of the user's foot. The gait improvement support system according to claim 1.   The measuring means measures the acceleration and direction of a predetermined part of the user's foot with a biaxial or more acceleration sensor and a triaxial geomagnetic sensor attached to the predetermined part of the user's foot. The gait improvement support system according to Item 1.   The measuring means measures a reaction force from the ground applied to the sole of the user by a pressure sensor provided on a sole of a shoe worn by the user or an acceleration sensor mounted on the ankle of the user. A gait improvement support system according to any one of claims 1 to 3.

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