JP6123520B2 - Lower limb shape change measuring device, method and program - Google Patents

Description

  The present invention relates to a lower limb shape change measuring apparatus, method, and program.

  Human muscle mass and strength decline with age. In particular, when the muscle strength of the human lower limbs declines, it becomes difficult to stand up, sit down, walk, etc., and the possibility of falling will increase, which will hinder daily life. On the other hand, it is known that muscle mass and muscle strength are generally proportional.

  Therefore, if the muscle mass of the lower limbs of the subject is measured, the muscle strength of the lower limbs can be obtained. For example, if the muscle mass of the lower limbs is periodically measured and changes in the muscle strength of the lower limbs are observed, the muscle strength declines early. Can be found. Thereby, the instruction | indication, treatment, etc. which maintain the test | inspection muscle strength of a test subject to the grade which can be walked are attained.

  However, it is difficult to accurately measure the muscle mass of the lower limb of the subject for the following reasons. First, since the thickness of the bones of the lower limbs and the amount of fat differ depending on the person, even if the thickness of a specific part of the lower limbs is measured, for example, an accurate muscle mass cannot be measured. Secondly, when the muscle mass is approximated from the thickness of the specific part of the lower limb, it is difficult to accurately measure the thickness by specifying the specific part of the lower limb accurately every time. Thirdly, in the case of an elderly subject in particular, it is difficult to stop at the same position at the time of measurement, but measurement becomes difficult if the subject moves. Fourth, if the posture of the subject is not the same every time at the time of measurement, the part of the lower limb in which the force is applied changes, so that the thickness of the specific part to be measured changes, resulting in a measurement error. Further, if the posture of the subject is not the same every time during measurement, it is difficult to accurately grasp the change in muscle strength even if the measured values are compared.

  In order to reduce the measurement error when the measurer manually measures the thickness of the lower limb of the subject using a tape measure, the thickness of the lower limb is measured, such as CT (Computed Tomography), MRI (Magnetic Resonance Imaging), etc. A measuring device can be used. However, if the subject is stationary and the subject is fixed to the measuring device or the measurement base with a belt or the like so that the posture of the subject is the same every time, the load on the subject increases. Here, the load on the subject means discomfort, fatigue, mental and physical stress, etc. felt by the subject. Further, even if the subject is fixed to a measurement table or the like with a belt or the like, it is difficult to fix the subject in the same posture every time, and the reproducibility of the measurement conditions is poor. Furthermore, since the operator who operates the measuring device operates the measuring device after the subject is stationary or fixed, the measurement takes time (ie, manpower and time), and the load on the operator is large. turn into.

JP-A-11-101623 JP 2011-002907 A JP 2012-0665805 A JP 2008-161228 A JP 2011-177278 A JP 2003-204953 A

Hirohide Iwata et al., “Measurement of lower limb volume with a three-dimensional shape measuring device”, Angiology, 200501025, Volume: 45: 10: 783

  In the prior art, it is difficult to accurately determine the change in the lower limb shape of the subject.

  Accordingly, an object of the present invention is to provide a lower limb shape change measuring device, method and program capable of accurately determining a change in the lower limb shape of a subject.

  According to an aspect of the present invention, the image processing apparatus includes an imaging unit that captures a lower limb of a walking subject and outputs image data, and a posture measurement unit that measures the posture of the lower limb of the subject and outputs posture data. Data and a measurement unit that outputs measurement data including posture data of the lower limb of the subject, three-dimensional shape data of the lower limb of the subject calculated from the image data for the measurement data at each time, and posture of the lower limb A difference between a shape calculation unit that stores data in a storage unit and a pair of data measured in the past and stored in the storage unit, and posture data of a lower limb of the data pair at the time of measurement is a threshold value A lower limb shape change measuring device provided with a shape displacement determination unit that compares three-dimensional shape data paired with the following posture data and three-dimensional shape data of a pair of data at the time of measurement, and determines a displacement of the three-dimensional shape. It is subjected.

  According to the disclosed lower limb shape change measuring device, method, and program, it is possible to accurately determine a change in the lower limb shape of a subject.

It is a block diagram which shows an example of the leg shape change measuring apparatus in 1st Example. It is a figure which shows an example of a measurement part. It is a figure which shows an example of the measurement data output from a measurement part. It is a figure which shows an example of the pressure data which a weight shake meter outputs. It is a figure which shows an example of the pressure distribution of the test subject's sole which the gravity center shake meter measured. It is a figure which shows an example of the picked-up image of the test subject's leg which the imaging part image | photographed. It is a block diagram which shows an example of a computer system. It is a flowchart explaining an example of a measurement part control process. It is a perspective view explaining the ridgeline of a leg. It is a figure explaining direction of a toe. It is a figure explaining conversion of the three-dimensional position coordinate of a leg. It is a perspective view explaining a visual field boundary. It is a flowchart explaining an example of a shape calculation process. It is a figure which shows an example of the data stored as a result of a shape calculation process. It is a flowchart explaining an example of a shape data storage process. It is a figure which shows an example of the data stored as a result of a shape data accumulation | storage process. It is a flowchart explaining an example of optimal shape data selection processing. It is a flowchart explaining an example of a shape displacement determination process. It is a figure which shows an example of the data output as a result of a shape displacement determination process. It is a figure which shows an example of the measurement part of the leg shape change measuring apparatus in 2nd Example. It is a flowchart explaining the 1st example of a measurement part control process. It is a figure explaining an example of determination of the walk cycle based on acceleration data. It is a figure explaining an example of the estimation of the attitude | position of the leg based on angular velocity data. It is a figure explaining an example of the rocking | fluctuation of the waist | lumbar part accompanying a test subject's walk. It is a flowchart explaining an example of a measurement part control process. It is a figure which shows an example of COP. It is a figure explaining an example of the up-and-down fluctuation of a hip joint. It is a figure explaining an example of the movable locus | trajectory of a hip joint. It is a figure explaining an example of the movable locus | trajectory of a hip joint. It is a figure explaining an example of the circumference which can become a position of a foot pressure center.

  In the disclosed lower limb shape change measuring device, method, and program, the measurement unit captures the lower limb of the walking subject and outputs image data, and the orientation measurement that measures the lower limb posture of the subject and outputs the posture data And output measurement data including image data and posture data of the lower limb of the subject. The shape calculation unit stores the three-dimensional shape data of the lower limb of the subject calculated from the image data and the posture data of the lower limb in pairs in the storage unit for the measurement data at each time. The shape displacement determination unit is a three-dimensional shape that forms a pair with the posture data whose difference from the posture data of the lower limb of the data pair at the time of measurement is equal to or less than a threshold among the data pairs measured in the past and stored in the storage unit The three-dimensional shape data of the data and the data at the time of measurement are compared to determine the displacement of the three-dimensional shape.

  Hereinafter, embodiments of the disclosed lower limb shape change measuring apparatus, method, and program will be described with reference to the drawings.

  FIG. 1 is a block diagram showing an example of a lower limb shape change measuring device in the first embodiment. A lower limb shape change measuring device 10 shown in FIG. 1 includes a measuring unit 11, a shape calculating unit 12, a shape data accumulating unit 13, an optimum shape data selecting unit 14, and a shape displacement determining unit 15.

  FIG. 2 is a diagram illustrating an example of the measurement unit 11. The measurement unit 11 illustrated in FIG. 2 includes a gravity center sway meter 111 that is an example of a pressure gauge, and imaging units 112-1 and 112-2. The sway sensor 111 has, for example, a configuration in which a plurality of pressure sensors are arranged in a matrix, detects pressure applied in a direction perpendicular to the surface pressure detection surface 111A, and detects the detected pressure distribution. It has a known configuration for outputting pressure data indicating the coordinate values and pressure values of feature points. Therefore, when the subject walks on the pressure detection surface 111 </ b> A of the sway meter 111, the pressure distribution of the subject's sole (the sole of the foot) is measured. The subject preferably walks on the pressure detection surface 111A with bare feet so that the pressure distribution of the sole of the subject can be accurately measured, but wears socks or footwear as long as the pressure distribution of the sole can be detected. May be. The area of the pressure detection surface 111A is not particularly limited as long as it is larger than the area where the subject can stand upright on the pressure detection surface 111A. The length of the subject in the walking direction is, for example, the subject walking one step on the pressure detection surface 111A. Even if it is the length which can be performed, it may be the length which a test subject can walk two steps or more on the pressure detection surface 111A.

The imaging units 112-1 and 112-2 have the same configuration including the projector 113 and the camera 114. In this example, for convenience, the xyz coordinate system is used, the pressure detection surface 111A of the surface of the centroid shaker 111 is installed on the xy plane parallel to the ground, and the imaging units 112-1 and 112-2 are swayed on the y axis. Installed on both sides of the total 111. The subject walks in the x-axis direction, for example, and the imaging units 112-1 and 112-2 are heights on the z-axis that can photograph the subject's lower limb 500 walking on the pressure detection surface 111 </ b> A of the gravity center sway meter 111. Install in position. The projector 113 irradiates a grid pattern, and the camera 114 captures the irradiation grid pattern from the projector 113 projected onto the lower limb 500 of the subject walking on the pressure detection surface 111A of the sway meter 111. In this example, the optical axis of the projector 113 and the optical axis of the camera 114 do not coincide with each other and form a predetermined angle (> 0). Accordingly, the camera 114 of the imaging unit 112-1 captures the right image of the lower limb of the subject and outputs right image data, and the camera 114 of the imaging unit 112-2 captures the left image of the lower limb of the subject and outputs the left image. Output image data. The lattice pattern is not particularly limited as long as it is suitable for measuring the shape of the lower limb 500, and in this example, is a line pattern parallel to the xy plane at equal intervals. The measurement data output from the measurement unit 11 includes pressure data output from the sway sensor 111 and image data output from the imaging units 112-1 and 112-2. The imaging units 112-1 and 112-2 are configured such that the center-of-gravity sway meter 111 causes the subject to walk on the pressure detection surface 111A. The installation positions of the imaging units 112-1 and 112-2 face each other with a certain distance therebetween. If it does, it does not need to be on the y-axis, and any position that does not hinder the walking of the subject. The imaging units 112-1 and 112-2 are preferably fixed to a frame (not shown) such as a plate shape so that the positional relationship between the imaging units 112-1 and 112-2 can be kept constant. In this case, the center-of-gravity sway meter 111 may be installed on the frames of the imaging units 112-1 and 112-2.

  The lower limb shape change measuring device 10 is provided with a clock (not shown), and outputs pressure data indicating the coordinate values (that is, the feature point coordinates) of the feature points of the pressure distribution detected by the barycenter sway meter 111. In this case, the data is output together with time data such as the date and time when the feature point of the pressure distribution was detected, the time, and the detection time (period in which pressure is continuously detected). Further, when the right image data and the left image data of the images captured by the imaging units 112-1 and 112-2 are output, the date and time, the time, and the detection time (feature points) when the right image data and the left image data are captured. Is output together with time data such as a period during which the data is continuously detected. The output timing of the pressure data of the measurement unit 11 and the output timing of the image data of the imaging units 112-1 and 112-2 are synchronized. In this example, the common time data and the measurement unit 11 and the imaging unit 112-1, Measurement data including data output from 112-2 is output. FIG. 3 is a diagram illustrating an example of measurement data output from the measurement unit 11.

  For example, as shown in FIG. 4, the pressure data output from the gravitational shaker 111 may include time data, coordinate values of feature points of pressure distribution, and pressure values of feature points. In this case, the measurement data shown in FIG. 3 may include pressure values (that is, feature point pressures) of feature points as shown in FIG. 4 in addition to the feature point coordinates.

  FIG. 5 is a diagram illustrating an example of the pressure distribution of the subject's sole measured by the sway meter 111. 5A shows a state in which the heel portion of the subject's left sole has landed on the pressure detection surface 111A of the center of gravity shake meter 111, and FIG. 5B shows a state in which substantially the entire left foot of the subject has detected the pressure of the center of gravity shake meter 111. (C) is a state where the five-finger portion of the subject's left foot is landed on the pressure detection surface 111A of the center of gravity sway meter 111, and (d) is a state where the thumb part of the subject's left foot is swaying the center of gravity. The pressure distribution of the subject's sole in a state of landing on the 111 pressure detection surface 111A is shown. In FIG. 5, for convenience of explanation, the pressure distribution of the subject's sole is seen through from above, and the pressure of each part of the subject's sole is shown as black as the pressure is higher. In FIG. 5, (a) to (d) are states detected by the gravity center sway meter 111 at regular intervals. In FIG. 5, P indicates the center of the pressure distribution of the subject's sole, that is, the center of gravity of the contact surface with the pressure detection surface 111 </ b> A of the sole. The center of gravity P is an example of a feature point of pressure distribution. In the example shown in FIG. 5, the subject moves in the y-axis direction and the z-axis direction as the subject walks in the x-axis direction.

  FIG. 6 is a diagram illustrating an example of a captured image of the lower limb 500 of the subject captured by the imaging unit 112-2. 6, (a), (b), (c), and (d) are the states of (a), (b), (c), and (d) in FIG. It is the left side image of the lower leg 500 of the test subject who image | photographed. The imaging unit 112-1 captures a right image of the left leg 500 of the subject in the same manner as the target part imaging unit 112-2. The imaging unit 112-1 captures the right image of the right leg 500 of the subject as described above, and the imaging unit 112-2 captures the left image of the subject's right leg 500 as described above. To do. As will be described later, shape data such as the thickness of the lower limb 500 can be calculated based on the right and left images of the lower limb 500 taken by the imaging units 112-1 and 112-2.

  FIG. 7 is a block diagram illustrating an example of a computer system. The computer system 20 shown in FIG. 7 has a configuration in which a CPU (Central Processing Unit) 21, a storage unit 22, an input unit 23, a display unit 24, and an interface (I / F) 25, which are an example of a processor, are connected by a bus 26. Have Needless to say, the connection of each part in the computer system 20 is not limited to the connection by the bus 26 shown in FIG.

  The CPU 21 controls the entire computer system 20 and executes a measurement unit control process for controlling the operation timing of the measurement unit 11 shown in FIG. 1 by executing a program, or the shape calculation unit 12 shown in FIG. Functions such as the shape data storage unit 13, the optimum shape data selection unit 14, and the shape displacement determination unit 15 can be realized. The CPU 21 may include an internal clock or an internal timer that functions as a clock of the lower limb shape change measuring device 10. The storage unit 22 stores a program executed by the CPU 21, an intermediate result of an operation executed by the CPU 21, a program executed by the CPU 21, data used for the operation, and the like. The storage unit 22 can be formed of a computer-readable storage medium. The computer-readable storage medium may be a semiconductor storage device. When the computer-readable storage medium is a magnetic recording medium, an optical recording medium, a magneto-optical recording medium, or the like, the storage unit 22 can be formed by a reader / writer that reads and writes information from and on the loaded recording medium. . The input unit 23 can be formed with a keyboard or the like, and is used to input commands, data, and the like to the computer system 20. The display unit 24 displays a message to the operator, data related to the lower limb shape change measurement process, and the like. The I / F 25 can communicate with an external device including the measurement unit 11 in a wired or wireless manner.

  FIG. 8 is a flowchart for explaining an example of the measurement unit control process. The measurement unit control process shown in FIG. 8 can be executed by the CPU 21, for example, but can be executed by this processor when a processor is provided in the measurement unit 111. When the measurement unit control process is started in FIG. 8, the gravity center sway meter 111 is activated in step S11, and a new measurement ID is assigned to the subject ID of the subject to be measured in step S12. Next, the process including steps S13 to S15 and the process including steps S16 to S18 are executed in parallel.

  In step S13, the imaging units 112-1 and 112-2 are controlled to alternately irradiate a lattice pattern from the projector 113 of the imaging unit 112-1 and the projector 113 of the imaging unit 112-2. A grid pattern is alternately projected on the right and left sides of the lower limb 500 of the subject walking on the pressure detection surface 111A. In step S14, the lower limbs of the subject on the side on which the grid pattern is alternately projected by the camera 114 of the imaging unit 112-1 and the camera 114 of the imaging unit 112-2 by controlling the imaging units 112-1 and 112-2. 500 is photographed. Such alternate irradiation of the lattice pattern and alternate imaging of the lattice pattern projected onto the lower limbs 500 are performed at high speed from the viewpoint of improving the calculation accuracy of the three-dimensional shape described later. It is preferable that the irradiation of the first and second projections is substantially simultaneous, and the alternating shooting of the projected lattice pattern is substantially simultaneous. In step S15, the right image data obtained from the cameras 114 of the imaging units 112-1 and 112-2 and the left image data are imaged and the right image data forming the pair and the right image are captured. The time and the left image data forming the pair and the shooting time of the left image data are stored in the storage unit 22.

  The wavelength bands used by the projector 113 and the camera 114 of the imaging unit 112-1 are different from the wavelength bands used by the projector 113 and the camera 114 of the imaging unit 112-2, so that the imaging units 112-1 and 112-2 are used. It is also possible to prevent halation between the two cameras 114 facing each other during simultaneous shooting.

  On the other hand, in step S <b> 16, it is determined whether or not the center-of-gravity sway meter 111 detects the pressure of the sole of the subject's lower limb 500. If the decision result in the step S16 is YES, in a step S17, as described with reference to FIG. 5, the coordinates of the center of gravity (center) P in the pressure distribution of the subject's sole measured by the center of gravity sway meter 111 every predetermined time ( Hereinafter, it is also stored in the storage unit 22 together with the measured time T. In step S18, it is determined whether or not the pressure at the bottom of the lower limb 500 of the subject is not detected by the center of gravity shake meter 111. If the pressure at the bottom of the subject is detected and the determination result is NO, the process returns to step S16.

  After completion of the process including steps S13 to S15 and the process including steps S16 to S18 (when the determination result in step S18 is YES), the process proceeds to step S19. In step S <b> 19, the image data captured by the cameras 114 of the imaging units 112-1 and 112-2 is stored in the storage unit 22 within the detection time. In step S20, when the measurement of the left and right lower limbs 500 of the subject is completed, the operation of the sway meter 111 is stopped, and the process ends.

  In each of the imaging units 112-1 and 112-2, the optical axis of the projector 113 and the optical axis of the camera 114 do not coincide with each other, so the camera 114 captures the lattice pattern irradiated by the projector 113 and projected onto the lower limb 500 of the subject. Thus, the lattice pattern is deformed according to the surface shape of the lower limb 500. Therefore, by analyzing the captured image of the deformed lattice pattern, the three-dimensional shape of the target portion of the lower limb 500 (that is, the portion on which the lattice pattern is projected) can be calculated. Moreover, the change of the three-dimensional shape of the target part of the lower limb 500 can also be calculated. A well-known method and method can be used for such calculation of the three-dimensional shape and calculation of the change in the three-dimensional shape. That is, the three-dimensional shape of the target part of the lower limb 500 can be calculated using a known optical three-dimensional measurement method and calculation method applying triangulation.

  For example, it is possible to calculate the three-dimensional position coordinates of the portion on which the lattice pattern is projected from a photographed image of the lattice pattern projected on the lower limb 500 of the subject photographed by the camera 114 using a known optical three-dimensional measurement technique. . Of the line segments connecting the calculated three-dimensional position coordinates, the line segment indicated by the thick line in FIG. 9 connecting the contour lines is regarded as the ridge line 510 of the lower limb 500. The ridge line 510 can be used as one of the parameters representing the lower limb (or leg) posture of the subject. FIG. 9 is a perspective view for explaining a ridge line 510 of the lower limb 500. Further, based on the ridge line 510, the orientation of the lower limb 500, which is an example of the posture of the lower limb 500, is obtained. In this example, the direction of the lower limb 500 is the toe direction Q, and when the subject walks along the x-axis direction of the center of gravity sway meter 111, the ridge line 510 of the lower limb 500 is a pressure detection surface as shown in FIG. In the state extending perpendicularly to 111A (that is, the z-axis direction perpendicular to the ground), it is the x-axis direction. FIG. 10 is a diagram for explaining the toe direction Q. FIG. In a state where the ridge line 510 of the lower limb 500 is inclined at an angle (> 0) from the z axis on the xz plane with respect to the pressure detection surface 111A, the toe direction Q is similarly inclined on the xz plane. Therefore, for example, in FIG. 11, a lattice pattern calculated from a captured image of the lattice pattern captured with the ridge line 510 of the lower limb 500 as shown in FIG. The three-dimensional position coordinates of the part are converted into three-dimensional position coordinates when the ridge line 510 of the lower limb 500 is rotated by an angle α to a state parallel to the z-axis as shown in FIG. FIG. 11 is a diagram for explaining the conversion of the three-dimensional position coordinates of the lower limb 500. A line parallel to the xy plane among the line segments connecting the three-dimensional position coordinates using the three-dimensional position coordinates after conversion of the lower limb 500 in which the toe direction Q is inclined from the x-axis direction. The minute is selected and the circumference (or circumference) of the corresponding part of the lower limb 500 is calculated.

  In the photographed image photographed by the camera 114, as shown in FIG. 12, a visual field boundary 520 is generated at the portion indicated by the thick line of the lower limb 500 due to the limit of the photographing range. FIG. 12 is a perspective view for explaining the visual field boundary 520. Such a visual field boundary 520 similarly occurs in a captured image captured by either camera 114 of the imaging units 112-1 and 112-2. Therefore, for the visual field boundary 520, the image data missing at the visual field boundary 520 may be interpolated by using known linear interpolation using the position coordinates of the pixels adjacent to the visual field boundary 520. By performing such interpolation, the shape calculation accuracy is improved. As a pixel adjacent to the visual field boundary 520 used for interpolation, a pixel of a captured image captured by the cameras 114 of both the imaging units 112-1 and 112-2 may be used. In FIG. 12, reference numeral 118 denotes a frame to which the imaging units 112-1 and 112-2 are fixed.

  FIG. 13 is a flowchart illustrating an example of a shape calculation process executed by the shape calculation unit 12. The shape calculation process shown in FIG. 13 can be executed by the CPU 21, for example. Since the shape calculation process can be executed in the same manner for the left and right lower limbs 500 of the subject, the following description will explain the shape calculation process for one of the lower limbs 500. In this example, for example, when viewing the direction from the imaging unit 112-1 to the imaging unit 112-2 in FIG. 12, the left direction is a positive value in the x-axis direction, the right direction is a negative value in the x-axis direction, and the front direction Is a positive value in the y-axis direction, a depth direction is a negative value in the y-axis direction, an upward direction is a positive value in the z-axis direction, and a downward direction is a negative value in the z-axis direction.

When the shape calculation process starts in FIG. 13, in step S <b> 21, an image including an image of the lower limb 500 of the subject from the paired right image data and left image data output from the camera 14 of the imaging units 112-1 and 112-2. Extract data. The image data including the image of the lower limb 500 can be extracted based on, for example, extracting image data including a skin color image or comparing the brightness of the entire image with a threshold value. In step S22, "0" is substituted into a counter (i) that counts the number of pixels in the vertical direction (that is, the z-axis direction) of the image. In step S23, the column for the i-th row is selected from the lower end of the image, and the brightness L _i for the column is calculated. The brightness L _i for one row of the image may be an average value of the brightness of the pixels included in one row, for example. In step S24, it is determined whether or not the i + 1-th row exists in the image. If the determination result is NO, the process proceeds to step S27 described later.

On the other hand, if the decision result in the step S24 is YES, in a step S25, it is judged whether or not L _{i + 1} > L _i . If the decision result is YES, the process returns to the step S24. If the decision result in the step S25 is NO, in a step S26, three-dimensional position coordinates (C) are calculated using a known optical three-dimensional measurement method for all pixels included in the i-th row, and the number of rows i The data is stored in the storage unit 22 and the process returns to step S24.

  In this way, when there is the darkest row as compared with the upper and lower columns, the position coordinates in the three-dimensional space (that is, the three-dimensional position coordinates) are used for all pixels included in the row using a well-known pattern projection method. (C)) is calculated and stored together with the number of rows (i) at that time. In addition, the above processing is performed on all the rows of the extracted image, thereby calculating the three-dimensional position coordinates of the darkest row.

  In step S27, “1” is substituted into the counter (k), and in step S28, it is determined whether or not there is a three-dimensional position coordinate of i = k rows. If the decision result in the step S28 is NO, in a step S29, k is incremented to k = k + 1, and the process returns to the step S28. On the other hand, if the decision result in the step S28 is YES, a three-dimensional position coordinate of i rows is extracted in a step S30. In step S31, a pixel at a vertex having the maximum y-coordinate value is selected from the calculated three-dimensional position coordinates. In step S32, it is determined whether or not vertices have been selected for all rows. If the determination result is NO, the process returns to step S28.

  If the decision result in the step S32 is YES, an inclination angle (α) with respect to the z axis of the ridge line 510 of the lower limb 500 is calculated in a step S33. In step S34, based on the inclination angle (α), the three-dimensional position coordinate (C ′) when the ridge line 510 of the lower limb 500 is rotated by an angle α to a state parallel to the z axis is calculated. In step S35, z from the pressure detection surface 111A (that is, the xy plane) of the sway meter 111 is based on the converted three-dimensional position coordinates (C ′) of each image represented by the paired right image data and left image data. The circumference R (or circumference) of the lower limb 500 measured in a plane parallel to the xy plane is calculated for each height position in the axial direction. In step S36, it is determined whether or not the circumference R (or circumference) of the lower limb 500 has been calculated for all pairs of images. If the determination result is NO, the process returns to step S21, and the determination result is YES. If so, the process ends.

  FIG. 14 is a diagram illustrating a part of an example of data calculated by the shape calculation process and stored in the storage unit 22, for example. In the example shown in FIG. 14, the result of the shape calculation process includes, for example, the date and time, the orientation of the lower limb 500 with respect to the x axis, the rotation angle of the ridge line 510 after conversion, and the rotation angle of the ridge line 510 after conversion from the xy plane. And the circumference R of the lower limb 500 are included.

  FIG. 15 is a flowchart for explaining an example of the shape data accumulation process. The shape data accumulation process shown in FIG. 15 can be executed by the CPU 21, for example. In FIG. 15, when the shape data accumulation process starts, in step S41, in addition to the subject ID of the subject input from the input unit 23 by the operator or the subject in step S42, the measurement ID assigned to the subject ID. From the xy plane, the three-dimensional position coordinates (C ′) when the ridge line 510 of the lower limb 500 is rotated by an angle α to a state parallel to the z axis based on the image data, the image data capture time, and the tilt angle (α). The circumference R for each height position, the barycentric coordinates P that are feature point coordinates, the measurement time T, and the like are stored in, for example, a shape accumulation database (DB: Data-Base) in the storage unit 22. In step S43, the trajectory of the feature point obtained by combining the feature points of the sole pressure distribution for the measurement ID is calculated and stored in the storage unit 22, for example. In this example, in step S43, for the measurement ID, for example, the locus V of the center of gravity obtained by combining the coordinates of the center of gravity P as shown in FIGS. 6A to 6D (hereinafter also referred to as “foot pressure locus”). Is stored in the foot pressure locus database (DB) in the storage unit 22, for example, in combination with the measurement ID, and the process ends.

  FIG. 16 is a diagram illustrating a part of an example of data stored in the storage unit 22, for example, as a result of the shape data accumulation process. In the example shown in FIG. 16, the result of the shape data accumulation process includes, for example, the date and time, the detection time, the foot pressure coordinates on the foot pressure locus V, the rotation angle of the converted ridge line 510, and the like after each conversion. The rotation angle of the ridge line 510 includes the height from the xy plane, the circumference of the lower limb 500, and the like.

  FIG. 17 is a flowchart for explaining an example of the optimum shape data selection process. The optimum shape data selection process shown in FIG. 17 can be executed by the CPU 21, for example. In FIG. 17, when the optimum shape data selection process is started, in step S51, image data (X) having the same measurement ID and an inclination angle (α) of “0” is selected as optimum shape data. Are stored in the shape accumulation DB, and the process ends. If there is no image data with α = 0, the image data with the smallest α may be selected as the optimum shape data.

  FIG. 18 is a flowchart illustrating an example of the shape displacement determination process. The shape displacement determination process shown in FIG. 18 can be executed by the CPU 21, for example. In FIG. 18, when the shape displacement determination process is started, the foot pressure locus V is extracted from the foot pressure locus DB in step S61, and in step S62, the foot pressure locus V matches and the subject ID matches the subject ID. Data D ′ is extracted from the shape accumulation DB. In step S63, it is determined whether image data X ′ (α0) with α = 0 exists in the data D ′. If the decision result in the step S63 is NO, in a step S64, an image whose inclination angle (α) is almost parallel to the z axis, that is, an image having the smallest α is extracted from the data D ′ as X ′ (α0). I reckon. After step S64 or if the decision result in the step S63 is YES, in a step S65, the circumference R (X ′ (α0)) at the time of the image data X ′ (α0) is extracted from the data D ′. In step S66, h = 0 is substituted for the height h from the xy plane. In step S67, whether or not there is a difference in circumference between the height h of the image data X (α0) and the image data X ′ (α0). If the determination result is NO, the process ends.

  On the other hand, if the decision result in the step S67 is YES, in a step S68, it is judged whether or not there is a circumferential diameter difference even within a predetermined range above and below the height h. If the decision result is NO, the process is a step. Return to S67. If the decision result in the step S68 is YES, in a step S69, there is a change in the circumference R of the height h, that is, there is a displacement from the circumference R of the height h measured under the same conditions in the past. The determination is made and the process ends.

  In this manner, the value of the height h from the pressure detection surface 111A (that is, the xy plane) of the sway sensor 111 is increased from 0, and the image data X (α0) and the image data X ′ (α0) are used. If there is a circumferential diameter difference, it is determined that there is a displacement in the circumferential diameter R of the height h if there is a circumferential diameter difference even within a predetermined range (for example, 3 mm) of the upper limit of the height h.

  FIG. 19 is a diagram illustrating an example of data output as a result of the shape displacement determination process. In the example illustrated in FIG. 19, the result of the shape displacement determination process includes, for example, a height h from the xy plane, a displacement of the peripheral diameter R, and the like. The displacement of the circumferential diameter R represents, for example, a decrease in the circumferential diameter R if it is a negative value, and an increase in the circumferential diameter R if it is a positive value. The result of the shape displacement determination process may be output and displayed on the display unit 24, for example, may be output by a printer (not shown), or may be transmitted to an external device via the I / F 25. Further, the result of the shape displacement determination process may be stored in the storage unit 22, for example. For example, when the change (or difference) in the circumference R exceeds a threshold value, a warning message may be displayed on the display unit 24, and the change (or difference) in the circumference R of a part of the lower limb 500 sets the threshold value. If it exceeds, you may store in the memory | storage part 22 with the medical history of the said site | part, for example. Further, these threshold values may be set for each part of the lower limb 500.

  According to the said Example, the change of a test subject's leg shape can be measured correctly. In addition, since the change in the lower limb shape can be accurately measured, the strength of the lower limbs or a change in the muscular strength (for example, swelling of the lower limbs) can be accurately detected. Furthermore, when measuring the shape of the lower limbs of the subject, the subject is not stationary, and the same posture is not taken every time, so the load on the subject can be suppressed. When photographing the lower limbs of the subject, the subject only needs to wear, for example, a screening garment in which the calf is exposed. Therefore, the load on the subject can also be suppressed in this respect. Further, it is possible to suppress the burden on the operator without using a large and expensive measuring apparatus such as CT or MRI.

  Furthermore, according to the above-described embodiment, the feature point of the pressure distribution of the sole, for example, the center of gravity of the photographed image of the lower limb of the subject is the same or similar (that is, the difference of the center of gravity is equal to or less than the threshold value). ) The three-dimensional shapes calculated from the captured images taken in the state are compared, so that the reproducibility of the measurement conditions is good.

  The direction of the lower limb, which is an example of the posture of the subject's lower limb (the direction of the toe in the above example), is the characteristic point of the pressure distribution of the subject's sole or the trajectory of the foot pressure (that is, the characteristic point of the pressure distribution of the sole) For example, by the CPU 21. In this case, the sway sensor 111 and the computer system 20 (specifically, the CPU 21) can form an example of a posture measuring unit that measures the posture of the lower limb of the subject and outputs posture data. Further, in the case of obtaining the lower limb posture of the subject using the ridge line 510 of the lower limb 500 as in the example described with reference to FIG. 9, the gravity center sway meter 111, the imaging units 112-1, 112-2, and the computer system 20 (specifically, , CPU 21) can form an example of a posture measurement unit that measures the posture of the lower limb of the subject and outputs posture data.

  As will be described later, the direction of the lower limb, which is an example of the lower limb posture of the subject at the time of three-dimensional shape measurement, is attached to the lower limb of the subject based on the sensor output by attaching an acceleration sensor to the lower limb of the subject and the like. The optimum shape data selection process may be executed based on the lower limb posture.

  Next, a second embodiment of the present invention will be described. FIG. 20 is a diagram illustrating an example of a measurement unit of the lower limb shape change measuring device according to the second embodiment. 20, parts that are the same as the parts shown in FIG. 1 are given the same reference numerals, and explanation thereof is omitted. In the embodiment shown in FIG. 20, the center-of-gravity sway meter 111 is not provided, an acceleration sensor 115 that detects the acceleration of the subject's lower limb 500 is attached to the lower limb 500, and the angular velocity sensor 116 that detects the angular velocity of the subject's waist is the waist ( (Not shown). For example, the sensor 115 is worn with a belt or the like near the ankle of the lower limb 500, and the angular velocity sensor 116 is worn with a belt or the like on the waist of the subject, for example. The acceleration sensor 115 has a known configuration for outputting acceleration data indicating the detected acceleration, and the angular velocity sensor 116 has a known configuration for outputting angular velocity data indicating the detected angular velocity. The sensors 115 and 116 input acceleration data and angular velocity data to the lower limb shape change measuring device 10 by wireless communication. Each sensor 115 and 116 has a known configuration capable of wireless communication with, for example, the I / F 25 of the computer system 20 shown in FIG. In FIG. 20, 555 indicates a part of the ground (or floor).

  FIG. 21 is a flowchart illustrating a first example of measurement unit control processing. In FIG. 21, the same steps as those in FIG. 8 are denoted by the same reference numerals, and the description thereof is omitted. When the measurement unit control process starts in FIG. 21, the sensors 115 and 116 are turned on in step S11A. When a new measurement ID is assigned to the subject ID of the subject to be measured in step S12, the process including steps S13 to S15 and the process including steps S116 to S119 are executed in parallel.

  In step S116, the acceleration data output from the acceleration sensor 115 when the subject walks between the imaging units 112-1 and 112-2 is extracted as the acceleration data of the section in the walking state. In step S117, the mounting position of the acceleration sensor 115 on the lower limb 500 is estimated based on changes in acceleration data in the traveling direction and the gravity direction during walking. In step S118, the walking cycle is determined from the displacement of the maximum and minimum points of the biaxial acceleration data when the subject walks. In step S119, based on the walking cycle and the angular velocity data output from the angular velocity sensor 116, the orientation (for example, the toe orientation) of the lower limb 500, which is an example of the posture of the lower limb 500, is estimated.

  It is known that humans maintain dynamic equilibrium while repeating slight fluctuations in an upright posture. This sway is measured as the movement of the body center of gravity from the front, back, left, right, top and bottom directions, and the moment (value obtained by multiplying the weight by the distance) or the value measured as the movement distance is the sway of the center of gravity.

  It is known that the walking cycle is divided into, for example, a load inheritance period, a single leg support period, and a forward movement period of the swing leg. The load inheritance period includes an initial contact (or initial contact) in which tumor contact occurs and a load response period (or loading response) in which plantar contact occurs. The monopod support period includes the middle stance phase (or mid stance) and the last stance phase (or terminal stance) in which the swollen area occurs. The forward movement period of the free limbs is the period before the toe release (or play swing), the early stage of the free leg (or initial swing), which is the acceleration period, and the middle of the free leg (or mid) Swing) and the free leg end (or terminal swing) which is a deceleration period.

  Therefore, in step S118, from the acceleration data of the ankle in the walking state section output from the acceleration sensor 115, it is determined which walking cycle corresponds to the walking cycle among “tumor grounding” to “tumorous ground”. In step S119, the direction of the foot is determined from the angular velocity of the waist indicated by the angular velocity data output from the angular velocity sensor 116.

  Since the body stretches during a single leg support period, the position of the body's center of gravity also increases. On the other hand, during the both-leg support period, the position of the body center of gravity is lowest. Therefore, the change in the position of the body center of gravity can be determined from the acceleration in the gravity direction, that is, the acceleration in the Z-axis direction.

  FIG. 22 is a diagram illustrating an example of determination of a walking cycle based on acceleration data. 22A shows an example of acceleration when the acceleration sensor is attached to the abdomen of the subject, and FIG. 22B shows an example of acceleration when the acceleration sensor is attached to the outside of the calf of the subject. In FIG. 22, the vertical axis indicates the amplitude in arbitrary units, and the horizontal axis indicates the time in arbitrary units. Further, the acceleration in the X-axis direction corresponding to the traveling direction of the subject is a solid line, the acceleration in the Y-axis direction corresponding to the left-right direction with respect to the traveling direction of the subject is a dashed line, and the Z-axis direction corresponding to the vertical direction with respect to the traveling direction of the subject. The acceleration is indicated by a two-dot chain line. Furthermore, in FIG. 22, the upper part of (a) shows the image data of the lower limb 500 of the subject when the corresponding acceleration data is obtained, and the acceleration in the Z-axis direction during the single leg support period is indicated by Amin. It turns out that it becomes the minimum.

  FIG. 23 is a diagram for explaining an example of the estimation of the posture of the lower limb based on the angular velocity data. In FIG. 23, (a) shows an example of acceleration when the acceleration sensor is attached to the outer side of the subject's calf, and (b) shows an example of angular velocity when the angular velocity sensor is attached to the outer side of the subject's calf. In FIG. 23, the vertical axis indicates amplitude in arbitrary units, and the horizontal axis indicates time in arbitrary units. Further, the acceleration and angular velocity in the X-axis direction corresponding to the traveling direction of the subject are solid lines, and the acceleration and angular velocity in the Y-axis direction corresponding to the left-right direction with respect to the traveling direction of the subject correspond to the dashed line and the vertical direction with respect to the traveling direction of the subject. The acceleration and angular velocity in the Z-axis direction are indicated by a two-dot chain line. In this example, the angular velocity of the subject in the Z-axis direction is zero (0), that is, neutral with respect to the pelvis.

  FIG. 24 is a diagram for explaining an example of the shaking of the lower back as the subject walks. FIG. 24 schematically shows a plane of the lower body of the subject. When the subject walks in the X-axis direction, the pelvis forming the waist swings clockwise and counterclockwise (not shown) indicated by arrows in FIG. When the pelvis is shaken, it is shaken, for example, within a total range of 10 ° between the state TSt at the end of stance and the state TSw at the end of the free leg with respect to the state MSt in the middle of stance.

  Therefore, as shown in FIG. 23 (b), from the angular velocity data, the action of kicking out the subject's foot, the action of twisting the foot inward, and the like are determined, and the orientation of the lower limb 500, which is an example of the posture of the lower limb 500, is estimated. be able to.

  Returning to the description of FIG. 21, after the processing including steps S13 to S15 and the processing including steps S116 to S119 are completed, the processing proceeds to step S19. When the image data captured by the cameras 114 of the imaging units 112-1 and 112-2 within the detection time is stored in the storage unit 22 in step S19, the sensor 115 is turned off in step S20A, and the process ends.

  FIG. 25 is a flowchart illustrating a second example of the measurement unit control process. In FIG. 25, the same steps as those in FIG. 21 are denoted by the same reference numerals, and the description thereof is omitted. When a new measurement ID is assigned to the subject ID of the subject to be measured in step S12, the process including steps S13 to S15 and the process including steps S126 to S131 are executed in parallel.

In step S126, the acceleration data output from the acceleration sensor 115 when the subject walks between the imaging units 112-1 and 112-2 is extracted as the acceleration data of the walking state section. In step S127, the mounting position of the sensor 115 on the lower limb 500 is estimated based on changes in acceleration data in the traveling direction and the gravity direction during walking. In step S128, an initial position is set from image data showing the lower limb 500 of the single leg support period. Specifically, in step S128, the initial position is set from image data when the subject's foot is straight and the acceleration data in the direction of gravity is minimum. In step S129, the position of the body center of gravity (COG) drawn by the hip joint is estimated from the acceleration data output from the acceleration sensor 115 by calculation. In step S130, the position of the body center of gravity (COG) drawn by the estimated hip joint is input from the input unit 23 or is calculated from the subject's foot length L and acceleration data stored in the storage unit 22. The range C _Ltanθ drawn by _Ltanθ is calculated using the angle θ formed between the foot and the direction of gravity. In step S130, the center of the foot pressure (COP) is estimated by regarding that the point passing through the trajectory passing through the tangent line in the range C _Ltanθ when the acceleration data in the gravity direction is the minimum is the foot pressure center (COP). To do. Details of the estimation of the center of foot pressure (COP) will be described later. In step S131, based on the foot pressure center (COP) and the angular velocity data output from the angular velocity sensor 116, the orientation of the lower limb 500 (eg, the toe orientation), which is an example of the posture of the lower limb 500, is estimated.

  The center of gravity of the human body (COG) refers to the center of gravity of the hip joint, pelvis and trunk, and the center of foot pressure (COP) of the human body is the center of foot pressure from the ankle and foot. Point to. It is known that in a completely static standing position of a human being, when the COP is located directly below the COG and the positional relationship between the COG and the COP does not coincide on the horizontal plane, rotational torque is generated in the body. Since the tip of the COP vector during walking is not the position of the center of gravity of the body but the position of the hip joint, the positional relationship between the COP and the point where the COG is lowered to the ground does not match during walking.

  Therefore, in the second example, the trajectory drawn by the COP is estimated from the acceleration when the subject walks, the past data of the same trajectory stored in the storage unit 22 is searched, and the image data of the same lower limb posture is extracted. Then, the displacement of the three-dimensional shape of the lower limb is determined by comparing with the current image data.

  In the case of the same foot posture, when the COP is located at the same position, it can be assumed that the way in which the foot force is applied (that is, the degree of muscle expansion and contraction) is approximate. FIG. 26 is a diagram illustrating an example of the COP. As illustrated in FIG. 26, the COP is an intersection of a virtual straight line VL extending from the hip joint HP to the sole and the ground G.

  The COP can be estimated as follows, for example. First, assuming that the swing locus obtained from the acceleration of the foot is a map of the movable locus of the hip joint on the ground G formed on the XY plane, the movable locus of the hip joint is calculated from the acceleration data. Next, as described with reference to FIG. 24, the hip joint during walking swings back and forth, left and right, that is, in a range parallel to the XY plane within a total range of 10 °. Further, as shown in FIG. 27, the hip joint during walking swings up and down, that is, in a direction parallel to the YZ plane, for example, in the range of 4 ° to 7 °. For this reason, the position of the three-dimensional space of the hip joint during walking is estimated from the angular velocity data. FIG. 27 is a diagram for explaining an example of up and down movement of the hip joint.

  28 and 29 are diagrams illustrating an example of a movable locus of the hip joint. FIG. 28 is a view of the left lower limb as viewed from the X-axis direction (that is, a direction perpendicular to the YZ plane) as an example of the traveling direction, and FIG. 29 is a view illustrating the left lower limb in the Y-axis direction (that is, perpendicular to the XZ plane). FIG. 28 and 29, the upper part 311 of the left foot toe, the thumb 312 of the left foot, and the little finger 313 of the left foot are shown for convenience. The position of the hip joint is indicated by a circle with a staggered pattern, and the movable locus of the hip joint is indicated by a broken line. As shown in FIGS. 28 and 29, the position of the hip joint is indicated by a broken line according to the walking cycle in accordance with the posture of the foot at the time of the ground contact IC, the foot at the mid-stance phase MSt, and the foot at the end of the stance phase TSt. Move on a moving track.

  The walking cycle can be estimated from the angular velocity of the waist, but may be estimated from the acceleration of the lower limb (eg, ankle) as in the case of the first example.

  FIG. 30 is a diagram illustrating an example of a circumference that can be the position of the foot pressure center. FIG. 30 shows a case where the center of foot pressure (COP) is obtained for the right foot of the subject for convenience. The position of the hip joint is indicated by a circle with a staggered pattern. IC, MSt, and TSt indicate the positions of the hip joints at the time of the ground contact IC, the middle stance MSt, and the last stance TSt, respectively. The traveling direction indicated by the arrow is, for example, the X-axis direction.

Input or stored in the position of the body center of gravity (COG) drawn by the estimated hip joint, and using the subject's foot length L and the angle θ between the foot and the direction of gravity calculated from the acceleration data Then, the range C _Ltanθ drawn by _Ltanθ is calculated, and the point passing through the trajectory passing through the tangent line that becomes the range C _Ltanθ when the acceleration data in the gravitational direction is minimum is regarded as the foot pressure center (COP). Estimate the center (COP). In the example of FIG. 30, the trajectory passing through the tangent line that becomes the range C _Ltanθ when the acceleration data in the gravitational direction is minimum is the circumference.

  Returning to the description of FIG. 25, after the process including steps S13 to S15 and the process including steps S126 to S131 are completed, the process proceeds to step S19. When the image data captured by the cameras 114 of the imaging units 112-1 and 112-2 within the detection time is stored in the storage unit 22 in step S19, the sensor 115 is turned off in step S20A, and the process ends.

  Thereby, in the present embodiment, the shape displacement determination unit 15 determines that the difference between the measurement data pair of the data measured in the past and stored in the storage unit 22 and the posture data of the lower limbs at the time of measurement is equal to or less than the threshold value. The three-dimensional shape data paired with the posture data is compared with the three-dimensional shape data of the measurement data pair to determine the displacement of the three-dimensional shape.

  Note that the orientation of the lower limb may be estimated based on the angular velocity data by attaching the angular velocity sensor 116 to the ankle instead of the waist. In this case, the acceleration sensor 115 and the angular velocity sensor 116 can be formed by a sensor unit in which these sensors 115 and 116 are integrally provided.

  In the case of the present embodiment, the sensor 115 and the computer system 20 (specifically, the CPU 21) can form an example of a posture measurement unit that measures the posture of the lower limb of the subject and outputs posture data. As in this embodiment, the orientation of the lower limb, which is an example of the lower limb posture of the subject at the time of measuring the three-dimensional shape, is determined based on the output data of the sensor 115, and the optimum shape data selection process is executed based on the lower limb posture. In this case, since it is not necessary to directly measure the subject's foot pressure, the center-of-gravity sway meter can be omitted. Further, when the center of gravity shake meter is not provided, the position where the foot is landed when the subject walks is not limited to the pressure detection surface of the center of gravity shake meter. For this reason, the configuration of the lower limb shape change measuring device can be simplified, and the load on the subject can be suppressed.

  When the subject walks between the imaging units 112-1 and 112-2, for example, when walking along the arrow written on the ground, it is obtained from the ridge line 510 of the lower limb 500 as described with reference to FIG. 9. The direction of the lower limb of the subject may be used as an example of the lower limb posture. In this case, the imaging units 112-1 and 112-2 and the computer system 20 (specifically, the CPU 21) can form an example of a posture measurement unit that measures the lower limb posture of the subject and outputs posture data.

The following supplementary notes are further disclosed with respect to the embodiments including the above examples.
(Appendix 1)
An imaging unit that captures a lower limb of a walking subject and outputs image data; and a posture measuring unit that measures the lower limb posture of the subject and outputs posture data, the image data and posture data of the lower limb of the subject A measurement unit that outputs measurement data including
For the measurement data at each time, the shape calculation unit that stores the three-dimensional shape data of the lower limb of the subject calculated from the image data and the posture data of the lower limb in a storage unit,
Of the data pairs measured in the past and stored in the storage unit, at the time of measurement, the three-dimensional shape data paired with posture data whose difference from the posture data of the lower limb of the data pair at the time of measurement is equal to or less than a threshold value A device for measuring a change in shape of a lower limb, comprising a shape displacement determination unit that compares the three-dimensional shape data of a pair of data and determines a displacement of the three-dimensional shape.
(Appendix 2)
The imaging unit includes a pair of imaging units that shoot the lower limbs of the subject from positions facing when the subject walks and output image data of one side of the lower limbs from each of the imaging units. Described lower limb shape change measuring device.
(Appendix 3)
The measurement unit has a pressure gauge that measures pressure at the sole of the subject and outputs pressure data,
The measurement unit outputs measurement data including the characteristic points of the pressure distribution of the sole of the subject calculated from the pressure data and the image data,
The shape calculation unit includes a pair of a characteristic point of the pressure distribution of the sole of the subject and the three-dimensional shape data of the lower limb of the subject calculated from the image data for the measurement data at each time. Stored in
The shape displacement determination unit includes a pair of feature points whose difference from a feature point of the pressure distribution of the data pair at the time of measurement is less than or equal to a threshold value among pairs of data measured in the past and stored in the storage unit. 3. The lower limb shape change measuring device according to appendix 1 or 2, characterized in that the three-dimensional shape data of the pair of the three-dimensional shape data and the data at the time of measurement are compared to determine the displacement of the three-dimensional shape.
(Appendix 4)
4. The lower limb shape change measuring device according to appendix 3, wherein the characteristic point of the pressure distribution of the sole of the subject is the center of gravity of the pressure distribution.
(Appendix 5)
The shape calculation unit converts the three-dimensional position coordinates of the image data in a state in which the lower limb of the subject is inclined from a perpendicular to the ground into three-dimensional position coordinates rotated to a state parallel to the perpendicular, and then The apparatus for measuring a change in a lower limb shape according to appendix 3 or 4, characterized by calculating data on a three-dimensional shape of a lower limb of a subject.
(Appendix 6)
The measurement data further comprises an optimum shape data selection unit for selecting image data in a state in which the lower limb of the subject is parallel to a perpendicular to the ground and storing the image data in the storage unit as optimum shape data, The lower limb shape change measuring device according to any one of appendices 3 to 5.
(Appendix 7)
The measurement unit includes a sensor that is attached to the subject and outputs acceleration data indicating acceleration of the lower limbs and angular velocity data indicating detected angular velocity,
The measurement unit determines a walking cycle from the displacement of the maximum and minimum points of biaxial acceleration data during walking of the subject, estimates the posture of the lower limb based on the walking cycle and the angular velocity data, The lower limb shape change measuring device according to appendix 1 or 2, wherein measurement data including posture data of the lower limb of the subject and the image data is output.
(Appendix 8)
The measurement unit includes a sensor that is attached to the subject and outputs acceleration data indicating acceleration of the lower limbs and angular velocity data indicating detected angular velocity,
The measurement unit estimates the position of the body center of gravity drawn by the hip joint of the subject from the acceleration data, and forms the position of the body center of gravity between the foot length of the subject and the direction of gravity calculated from the acceleration data. The range drawn using the angle is calculated, the foot pressure center is estimated from the point passing through the trajectory passing through the tangential line when the acceleration data in the gravitational direction is minimum, and the foot pressure center is calculated as the angular velocity data. 3. The lower limb shape change measuring device according to appendix 1 or 2, wherein measurement data including posture data of the lower limbs of the subject and the image data is output.
(Appendix 9)
9. The lower limb shape determination device according to appendix 7 or 8, wherein the sensor includes an acceleration sensor mounted near the ankle of the subject and an angular velocity sensor mounted on the waist of the subject.
(Appendix 10)
The said shape displacement determination part displays a message on a display part, if the difference of the compared three-dimensional shape data exceeds a threshold value, The leg shape change determination apparatus of any one of Additional remarks 1 thru | or 9 characterized by the above-mentioned.
(Appendix 11)
The image data from the imaging unit that images the lower limb of the walking subject and outputs image data, and the measurement unit that measures the lower limb posture of the subject and outputs the posture data, and the lower limb of the subject A measurement procedure for obtaining measurement data including posture data;
For the measurement data at each time, a shape calculation procedure for storing the three-dimensional shape data of the lower limb of the subject calculated from the image data and the posture data of the lower limb in a storage unit,
Of the data pairs measured in the past and stored in the storage unit, at the time of measurement, the three-dimensional shape data paired with posture data whose difference from the posture data of the lower limb of the data pair at the time of measurement is equal to or less than a threshold value A method of measuring a lower limb shape change, comprising a shape displacement determination procedure for comparing the three-dimensional shape data of a pair of data and determining a displacement of the three-dimensional shape.
(Appendix 12)
The measurement procedure uses a pair of imaging units that capture images of the lower limbs of the subject from positions facing when the subject walks and output image data on one side of the lower limbs from the imaging unit. The lower limb shape change measuring method according to appendix 11.
(Appendix 13)
The measurement unit has a pressure gauge that measures pressure at the sole of the subject and outputs pressure data,
The measurement procedure outputs the measurement data including the feature points of the pressure distribution of the subject's sole calculated from the pressure data and the image data,
For the measurement data at each time, the shape calculation procedure includes a pair of a feature point of pressure distribution of the subject's sole and a three-dimensional shape data of the lower limb of the subject calculated from the image data. Stored in
In the shape displacement determination procedure, a pair of data points measured in the past and stored in the storage unit is paired with a feature point whose difference from a pressure distribution feature point of the data pair at the time of measurement is equal to or less than a threshold value. 14. The method for measuring a lower limb shape change according to appendix 12 or 13, wherein the three-dimensional shape data of the pair of the three-dimensional shape data and the data at the time of measurement are compared to determine the displacement of the three-dimensional shape.
(Appendix 14)
14. The lower limb shape change measuring method according to appendix 13, wherein the feature point of the pressure distribution of the subject's sole is the center of gravity of the pressure distribution.
(Appendix 15)
In the shape calculation procedure, the three-dimensional position coordinates of the image data in a state where the lower limbs of the subject are inclined from the perpendicular to the ground are converted into the three-dimensional position coordinates rotated to a state parallel to the perpendicular, and then the shape calculation procedure is performed. 15. The method for measuring a change in a lower limb shape according to appendix 13 or 14, wherein data of a three-dimensional shape of a lower limb of a subject is calculated.
(Appendix 16)
The method further includes an optimum shape data selection procedure for selecting image data in which the lower limb of the subject is parallel to a perpendicular to the ground from the measurement data and storing the image data as optimum shape data in the storage unit. The lower limb shape change measurement method according to any one of 13 to 15.
(Appendix 17)
The measurement unit includes a sensor that is attached to the subject and outputs acceleration data indicating acceleration of the lower limbs and angular velocity data indicating detected angular velocity,
The measurement procedure determines the cycle of walking from the displacement of the maximum point and the minimum point of biaxial acceleration data during walking of the subject, estimates the lower limb posture based on the cycle of walking and the angular velocity data, 14. The lower limb shape change measurement method according to appendix 12 or 13, wherein measurement data including posture data of the lower limb of the subject and the image data is output.
(Appendix 18)
The measurement unit includes a sensor that is attached to the subject and outputs acceleration data indicating acceleration of the lower limbs and angular velocity data indicating detected angular velocity,
In the measurement procedure, the position of the body center of gravity drawn by the hip joint of the subject is estimated from the acceleration data by calculation, and the position of the body center of gravity is defined by the foot length calculated from the subject's foot length and acceleration data and the direction of gravity. The range drawn using the angle is calculated, the foot pressure center is estimated from the point passing through the trajectory passing through the tangential line when the acceleration data in the gravitational direction is minimum, and the foot pressure center is calculated as the angular velocity data. The measurement method including the posture data of the lower limbs of the subject and the measurement data including the image data is output based on the limb shape change measurement method according to appendix 12 or 13.
(Appendix 19)
19. The lower limb shape determination method according to appendix 17 or 18, wherein the sensor includes an acceleration sensor worn near the ankle of the subject and an angular velocity sensor worn on the waist of the subject.
(Appendix 20)
The lower limb shape change determination method according to any one of appendices 12 to 19, wherein the shape displacement determination procedure displays a message on a display unit when a difference between the compared three-dimensional shape data exceeds a threshold value.
(Appendix 21)
A program for causing a computer to execute a process of measuring a shape change of a lower limb of a subject,
The image data from the imaging unit that images the lower limb of the walking subject and outputs image data, and the measurement unit that measures the lower limb posture of the subject and outputs the posture data, and the lower limb of the subject A measurement procedure for obtaining measurement data including posture data;
For the measurement data at each time, a shape calculation procedure for storing the three-dimensional shape data of the lower limb of the subject calculated from the image data and the posture data of the lower limb in a storage unit,
Of the data pairs measured in the past and stored in the storage unit, at the time of measurement, the three-dimensional shape data paired with posture data whose difference from the posture data of the lower limb of the data pair at the time of measurement is equal to or less than a threshold value A program for causing a computer to execute a shape displacement determination procedure for comparing three-dimensional shape data of a pair of data and determining a displacement of a three-dimensional shape.
(Appendix 22)
The image data from the measurement unit is output from a pair of imaging units that shoot the lower limbs of the subject from positions facing when the subject walks and output image data on one side of the lower limbs from each. The program according to appendix 21, characterized by being.
(Appendix 23)
The measurement unit has a pressure gauge that measures pressure at the sole of the subject and outputs pressure data,
The measurement procedure outputs the measurement data including the feature points of the pressure distribution of the subject's sole calculated from the pressure data and the image data,
For the measurement data at each time, the shape calculation procedure includes a pair of a feature point of pressure distribution of the subject's sole and a three-dimensional shape data of the lower limb of the subject calculated from the image data. Stored in
In the shape displacement determination procedure, a pair of data points measured in the past and stored in the storage unit is paired with a feature point whose difference from a pressure distribution feature point of the data pair at the time of measurement is equal to or less than a threshold value. The program according to appendix 21 or 22, wherein the three-dimensional shape data of the pair of the three-dimensional shape data and the data at the time of measurement are compared to determine the displacement of the three-dimensional shape.
(Appendix 24)
24. The program according to appendix 23, wherein the feature point of the pressure distribution of the sole of the subject is the center of gravity of the pressure distribution.
(Appendix 25)
In the shape calculation procedure, the three-dimensional position coordinates of the image data in a state where the lower limbs of the subject are inclined from the perpendicular to the ground are converted into the three-dimensional position coordinates rotated to a state parallel to the perpendicular, and then the shape calculation procedure is performed. 25. The program according to appendix 23 or 24, characterized in that the data of the three-dimensional shape of the lower limb of the subject is calculated.
(Appendix 26)
Of the measurement data, the computer further executes an optimal shape data selection procedure for selecting image data in a state in which the lower limb of the subject is parallel to a perpendicular to the ground and storing the image data as optimal shape data in the storage unit. The program according to any one of appendices 23 to 25.
(Appendix 27)
The measurement unit includes a sensor that is attached to the subject and outputs acceleration data indicating acceleration of the lower limbs and angular velocity data indicating detected angular velocity,
The measurement procedure determines the cycle of walking from the displacement of the maximum point and the minimum point of biaxial acceleration data during walking of the subject, estimates the lower limb posture based on the cycle of walking and the angular velocity data, The program according to appendix 21 or 22, wherein measurement data including posture data of the lower limbs of the subject and the image data is output.
(Appendix 28)
The measurement unit includes a sensor that is attached to the subject and outputs acceleration data indicating acceleration of the lower limbs and angular velocity data indicating detected angular velocity,
In the measurement procedure, the position of the body center of gravity drawn by the hip joint of the subject is estimated from the acceleration data by calculation, and the position of the body center of gravity is defined by the foot length calculated from the subject's foot length and acceleration data and the direction of gravity. The range drawn using the angle is calculated, the foot pressure center is estimated from the point passing through the trajectory passing through the tangential line when the acceleration data in the gravitational direction is minimum, and the foot pressure center is calculated as the angular velocity data. 23. The program according to appendix 21 or 22, wherein measurement data including posture data of the lower limb of the subject and the image data is output based on the program.
(Appendix 29)
29. The method for determining a lower limb shape according to appendix 27 or 28, wherein the sensor includes an acceleration sensor mounted near the ankle of the subject and an angular velocity sensor mounted on the waist of the subject.
(Appendix 30)
30. The program according to any one of appendices 21 to 29, wherein the shape displacement determination procedure displays a message on a display unit when a difference between the compared three-dimensional shape data exceeds a threshold value.

  As described above, the lower limb shape change measuring device, method, and program disclosed have been described by way of examples. However, the present invention is not limited to the above examples, and various modifications and improvements can be made within the scope of the present invention. Needless to say.

DESCRIPTION OF SYMBOLS 10 Lower limb shape change measuring apparatus 11 Measurement part 12 Shape calculation part 13 Shape data storage part 14 Optimal shape data selection part 15 Shape displacement determination part 20 Computer system 21 CPU
22 storage unit 111 center of gravity shake meter 111A pressure detection surface 112-1, 112-2 imaging unit 113 projector 114 camera 115 acceleration sensor 116 angular velocity sensor

Claims (7)

An imaging unit that captures a lower limb of a walking subject and outputs image data; and a posture measuring unit that measures the lower limb posture of the subject and outputs posture data, the image data and posture data of the lower limb of the subject A measurement unit that outputs measurement data including
For the measurement data at each time, the shape calculation unit that stores the three-dimensional shape data of the lower limb of the subject calculated from the image data and the posture data of the lower limb in a storage unit,
Of the data pairs measured in the past and stored in the storage unit, at the time of measurement, the three-dimensional shape data paired with posture data whose difference from the posture data of the lower limb of the data pair at the time of measurement is equal to or less than a threshold value A device for measuring a change in shape of a lower limb, comprising a shape displacement determination unit that compares the three-dimensional shape data of a pair of data and determines a displacement of the three-dimensional shape. The measurement unit has a pressure gauge that measures pressure at the sole of the subject and outputs pressure data,
The measurement unit outputs measurement data including the characteristic points of the pressure distribution of the sole of the subject calculated from the pressure data and the image data,
The shape calculation unit includes a pair of a characteristic point of the pressure distribution of the sole of the subject and the three-dimensional shape data of the lower limb of the subject calculated from the image data for the measurement data at each time. Stored in
The shape displacement determination unit includes a pair of feature points whose difference from a feature point of the pressure distribution of the data pair at the time of measurement is less than or equal to a threshold value among pairs of data measured in the past and stored in the storage unit. The lower limb shape change measuring device according to claim 1, wherein the three-dimensional shape data of the pair of the three-dimensional shape data and the data at the time of measurement are compared to determine the displacement of the three-dimensional shape.   The lower limb shape change measuring device according to claim 2, wherein the feature point of the pressure distribution of the subject's sole is the center of gravity of the pressure distribution. The measurement unit includes a sensor that is attached to the subject and outputs acceleration data indicating acceleration of the lower limbs and angular velocity data indicating detected angular velocity,
The measurement unit determines a walking cycle from the displacement of the maximum and minimum points of biaxial acceleration data during walking of the subject, estimates the posture of the lower limb based on the walking cycle and the angular velocity data, 2. The lower limb shape change measuring apparatus according to claim 1, wherein measurement data including posture data of the lower limb of the subject and the image data is output. The measurement unit includes a sensor that is attached to the subject and outputs acceleration data indicating acceleration of the lower limbs and angular velocity data indicating detected angular velocity,
The measurement unit estimates the position of the body center of gravity drawn by the hip joint of the subject from the acceleration data, and forms the position of the body center of gravity between the foot length of the subject and the direction of gravity calculated from the acceleration data. The range drawn using the angle is calculated, the foot pressure center is estimated from the point passing through the trajectory passing through the tangential line when the acceleration data in the gravitational direction is minimum, and the foot pressure center is calculated as the angular velocity data. 2. The lower limb shape change measuring device according to claim 1, wherein measurement data including posture data of the lower limb of the subject and the image data is output based on the measurement data. The image data from the imaging unit that images the lower limb of the walking subject and outputs image data, and the measurement unit that measures the lower limb posture of the subject and outputs the posture data, and the lower limb of the subject A measurement procedure for obtaining measurement data including posture data;
For the measurement data at each time, a shape calculation procedure for storing the three-dimensional shape data of the lower limb of the subject calculated from the image data and the posture data of the lower limb in a storage unit,
Of the data pairs measured in the past and stored in the storage unit, at the time of measurement, the three-dimensional shape data paired with posture data whose difference from the posture data of the lower limb of the data pair at the time of measurement is equal to or less than a threshold value A method of measuring a lower limb shape change, comprising a shape displacement determination procedure for comparing the three-dimensional shape data of a pair of data and determining a displacement of the three-dimensional shape. A program for causing a computer to execute a process of measuring a shape change of a lower limb of a subject,
The image data from the imaging unit that images the lower limb of the walking subject and outputs image data, and the measurement unit that measures the lower limb posture of the subject and outputs the posture data, and the lower limb of the subject A measurement procedure for obtaining measurement data including posture data;
For the measurement data at each time, a shape calculation procedure for storing the three-dimensional shape data of the lower limb of the subject calculated from the image data and the posture data of the lower limb in a storage unit,
Of the data pairs measured in the past and stored in the storage unit, at the time of measurement, the three-dimensional shape data paired with posture data whose difference from the posture data of the lower limb of the data pair at the time of measurement is equal to or less than a threshold value A program for causing a computer to execute a shape displacement determination procedure for comparing three-dimensional shape data of a pair of data and determining a displacement of a three-dimensional shape.