JP2012120648A - Posture detection apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately calculate a value indicative of a posture of a subject.SOLUTION: A posture detection apparatus includes: a range image acquisition part 102 where brightness values in respective pixel acquire a range image indicative of a range from a camera to the subject; a coordinate calculation part 104 that calculates a coordinate in three-dimensional space of a plurality of markers pasted on the subject based on the range image acquired by the range image acquisition part 102; and a posture calculation part 106 that calculates a value indicative of the posture of the subject from the coordinates of the plurality of markers calculated by the coordinate calculation part 104.

Description

  The present invention relates to a posture detection device, and more particularly to a posture detection device that is used in rehabilitation applications and that quantifies a human posture.

  Conventionally, a goniometer is known as a device for digitizing a human posture (see, for example, Patent Document 1).

  FIG. 23A and FIG. 23B are diagrams for explaining a method of calculating the rotation angle of the cervical spine using a goniometer. As shown in FIG. 23A, the goniometer 350 includes a first ruler 352 and a second ruler 354, and the first ruler 352 and the second ruler 354 are connected to be rotatable at a rotation center 356. Yes. The first ruler 352 has a scale indicating the angle formed by the first ruler 352 and the second ruler 354. First, when the subject 110 is facing the front as shown in FIG. 23A, the long axis of the first ruler 352 is aligned with the position parallel to both shoulder peaks of the subject 110, and in this state, the long axis of the second ruler 354 is When viewed from above the subject 110, the position is matched with a straight line connecting the top of the subject 110 and the space between the eyebrows. In this state, the angle formed by the first ruler 352 and the second ruler 354 is measured. Further, with the subject 110 turning his head to the right limit as shown in FIG. 23B, the positions of the first ruler 352 and the second ruler 354 are aligned with the same positions as in FIG. 23A, and the first ruler 352 and the first ruler 352 The angle formed by the two rulers 354 is measured. By calculating the difference between the angle measured in the state of FIG. 23B and the angle measured in the state of FIG. 23A, the rotation angle of the neck of the subject 110 can be calculated.

  FIG. 24A and FIG. 24B are diagrams for explaining a method of calculating an abduction angle when the right hip joint is abducted using a goniometer. As shown in FIG. 24A, for the subject 120 in the supine position with both legs closed, the rotation center 356 of the goniometer 350 is aligned with the right upper anterior iliac spine, and the right and left upper anterior iliac spines are aligned. The long axis of the first ruler 352 is aligned with the connecting straight line, and the long axis of the second ruler 354 is aligned with the straight line connecting the right upper anterior iliac spine and the center of the patella. In this state, the angle formed by the first ruler 352 and the second ruler 354 is measured. Further, in the state where the right hip joint is abducted as shown in FIG. 24B, the positions of the first ruler 352 and the second ruler 354 are adjusted to the same positions as in FIG. 24A, and the first ruler 352 and the second ruler 354 Measure the angle formed by. By calculating the difference between the angle measured in the state of FIG. 24B and the angle measured in the state of FIG. 24A, the abduction angle when the right hip joint of the subject 120 is abducted can be calculated. .

JP 2000-279536 A

  However, the method using a goniometer has a problem that a value indicating the posture of the subject cannot be accurately calculated.

  That is, in the method for calculating the rotation angle of the cervical vertebra shown in FIGS. 23A and 23B, as described above, the long axis of the first ruler 352 is aligned with the position parallel to the both shoulder ridges of the subject 110, and in this state, the second The major axis of the ruler 354 needs to be aligned with a position that matches the straight line connecting the top of the subject 110 and the space between the eyebrows when viewed from above the subject 110. However, both shoulder ridges and the first ruler 352 are separated in position, and the first ruler 352 cannot be directly applied to the shoulder. Moreover, since the space between the eyebrows and the second ruler 354 are separated in position, the second ruler 354 cannot be directly applied between the eyebrows. As described above, since it is difficult to align the first ruler 352 and the second ruler 354 with accurate positions, a value indicating the posture of the subject cannot be accurately calculated.

  In the method of calculating the abduction angle when the right hip joint is abducted as shown in FIGS. 24A and 24B, the rotation center 356 of the goniometer 350 is aligned with the right anterior iliac spine as described above. The long axis of the first ruler 352 is aligned with the straight line connecting the right and left upper anterior iliac spines, and the long axis of the second ruler 354 is aligned with the straight line connecting the right upper anterior iliac spine and the center of the patella. It is necessary to match. However, in the angle measurement when the right hip joint is abducted, the movement angle to the side of the thigh is measured based on the position of the pelvis. In this movement, a so-called compensatory movement in which the pelvis itself tilts occurs. For this reason, since it is difficult to align the first ruler 352 and the second ruler 354 with accurate positions, a value indicating the posture of the subject cannot be accurately calculated.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a posture detection device and the like that can accurately calculate a value indicating the posture of a subject.

  In order to achieve the above object, a posture detection apparatus according to an aspect of the present invention includes a distance image acquisition unit that acquires a distance image in which a luminance value in each pixel indicates a distance from a camera to a subject, and the distance image acquisition unit Based on the acquired distance image, a coordinate calculation unit that calculates coordinates in a three-dimensional space of a plurality of markers attached to the subject, and from the coordinates of the plurality of markers calculated by the coordinate calculation unit, A posture calculation unit that calculates a value indicating the posture of the subject.

  According to this configuration, the coordinates in a three-dimensional space of a plurality of markers are calculated from the distance image, instead of applying a goniometer to the subject. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, a value indicating the posture of the subject can be accurately calculated from the coordinates of the plurality of markers.

  Preferably, the plurality of markers are affixed to the right and left ridges of the subject, the top of the head, and the space between the eyebrows, and the posture calculation unit rotates the head with the subject facing forward. The difference between the straight line connecting the marker affixed to the right and left acetabulum and the straight line connecting the marker affixed to the parietal region and the marker affixed between the eyebrows to the cervical vertebra Calculated as the rotation angle.

  According to this configuration, the coordinates in the three-dimensional space of the markers affixed to the subject's right and left shoulder ridges, the top of the head, and the eyebrows are calculated from the distance image, rather than hitting the goniometer on the subject. is doing. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the rotation angle of the subject's cervical spine can be accurately calculated from the coordinates of the plurality of markers.

  Further, the plurality of markers are affixed to the right and left upper anterior iliac spines and the patella of the right leg or the left leg of the subject, and the posture calculation unit is in a state in which the subject closes both legs, A straight line connecting the marker affixed to the right anterior iliac spine on the right side and the left side with the abduction movement of the leg-side hip joint with the marker affixed to the patella, and the marker affixed to the patella The difference between the angle formed by the straight line connecting the marker affixed to the upper anterior iliac spine on the leg side where the marker is affixed to the patella may be calculated as the abduction angle when the hip joint is abducted Good.

  According to this configuration, the goniometer is not applied to the subject, but from the distance image, in the three-dimensional space of the markers attached to the right and left upper anterior iliac spines and the right or left patella of the subject. The coordinates at are calculated. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the abduction angle when the hip joint of the subject is abducted can be accurately calculated from the coordinates of the plurality of markers.

  The plurality of markers are affixed to the subject's seventh cervical spinous process and the right and left upper posterior iliac spines, and the posture calculating unit is a marker affixed to the seventh cervical spinous process; An angle formed by a straight line connecting the midpoint of the two markers attached to the right and left upper posterior iliac spines and the center of gravity of the subject may be calculated as a trunk inclination angle.

  According to this configuration, the goniometer is not applied to the subject, but from the distance image, the marker attached to the subject's seventh cervical spine and the right and left upper iliac spines in the three-dimensional space. Coordinates are calculated. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the trunk inclination angle of the subject can be accurately calculated from the coordinates of the plurality of markers.

  The plurality of markers include a plurality of markers attached between the seventh cervical spinous process of the subject and the spinous processes of the lumbar vertebrae, and two markers attached to the right and left upper posterior iliac spines. The posture calculation unit includes a seventh line from a straight line connecting a marker affixed to the seventh cervical spinous process and a midpoint of the two markers affixed to the right and left upper posterior iliac spines. A first calculation unit for calculating a maximum value of a distance from a cervical spine process to a curve of a thoracic vertebra part among curves passing through the plurality of markers attached between the spinous process of the lumbar spine and the seventh cervical spine process; A second calculation unit that calculates a distance from the marker affixed to the point where the straight line and the curve intersect, and a distance that the second calculation unit calculates the maximum value calculated by the first calculation unit By calculating the value divided by The third may include a calculation unit for calculating the bay index after indicating the degree of the bay after's.

  According to this configuration, the goniometer is not applied to the subject, but from the distance image, the plurality of markers pasted from the subject's seventh cervical spinous process to the spinous process of the lumbar spine, and the right and left upper hindgut The coordinates in the three-dimensional space of the two markers attached to the osteophytes are calculated. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the rear bay index indicating the degree of the rear bay of the subject can be accurately calculated from the coordinates of the plurality of markers.

  The plurality of markers include a plurality of markers attached between the seventh cervical spinous process of the subject and the spinous processes of the lumbar vertebrae, and two markers attached to the right and left upper posterior iliac spines. The posture calculation unit includes a seventh line from a straight line connecting a marker affixed to the seventh cervical spinous process and a midpoint of the two markers affixed to the right and left upper posterior iliac spines. A first calculation unit for calculating a maximum value of a distance from a cervical spinous process to a lumbar part among curves passing through the plurality of markers attached between the spinous process of the lumbar vertebra, the straight line and the curve; A second calculation unit that calculates a distance from a point at which the two markers affixed to the right and left upper posterior iliac spines to the middle point, and the maximum value calculated by the first calculation unit Divided by the distance calculated by the second calculation unit By calculating it may include a third calculation unit for calculating a lordotic index indicating the degree of lordosis in the subject.

  According to this configuration, the goniometer is not applied to the subject, but from the distance image, the plurality of markers pasted from the subject's seventh cervical spinous process to the spinous process of the lumbar spine, and the right and left upper hindgut The coordinates in the three-dimensional space of the two markers attached to the osteophytes are calculated. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the front bay index indicating the degree of the front bay of the subject can be accurately calculated from the coordinates of the plurality of markers.

  In addition, the plurality of markers are affixed to the right and left shoulder ridges of the subject and the lower edge of the right and left lowest auxiliary cartilage, and the posture calculation unit is affixed to the right and left acetabulums. An upper trunk vector calculation unit for calculating a vector connecting the marked markers as an upper trunk vector which is a vector indicating the direction of the upper trunk, and a marker affixed to the lower edge of the right and left lowest auxiliary cartilage A lower trunk vector calculation unit that calculates a vector connecting the two as a lower trunk vector that is a vector indicating a direction of the lower trunk, and the calculated upper trunk vector and the lower trunk vector are used as the frontal plane of the subject. And an inclination angle calculation unit that calculates an angle formed by the vectors projected onto the subject as an inclination angle between the upper trunk and the lower trunk of the subject.

  According to this configuration, the three-dimensional space of the markers affixed to the subject's right and left acicular ridges and the lower edge of the right and left lowest auxiliary cartilage from the distance image, rather than hitting the goniometer to the subject The coordinates inside are calculated. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the inclination angle between the upper trunk and the lower trunk of the subject can be accurately calculated from the coordinates of the plurality of markers.

  Further, the plurality of markers are affixed to the lower edge of the lowest prosthetic cartilage on the right side and the left side of the subject and the upper anterior iliac spine on the right side and the left side. A lower trunk vector calculation unit that calculates a vector connecting the markers attached to the lower edge of the lower auxiliary cartilage as a lower trunk vector that is a vector indicating the direction of the lower trunk, and the right and left upper anterior iliac bones A pelvis vector calculation unit that calculates a vector connecting the markers affixed to the spines as a pelvis vector that is a vector indicating the orientation of the pelvis, and projects the calculated lower trunk vector and the pelvis vector onto the frontal plane of the subject An inclination angle calculation unit that calculates an angle formed by the vectors as an inclination angle between the lower trunk of the subject and the pelvis may be included.

  According to this configuration, instead of applying a goniometer to the subject, from the distance image, the markers attached to the lower edge of the lowest costal cartilage on the right and left sides of the subject and the upper anterior iliac spine on the right and left sides Coordinates in 3D space are calculated. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the inclination angle between the lower trunk of the subject and the pelvis can be accurately calculated from the coordinates of the plurality of markers.

  In addition, the plurality of markers are affixed to the right and left shoulder ridges of the subject and the lower edge of the right and left lowest auxiliary cartilage, and the posture calculation unit is affixed to the right and left acetabulums. An upper trunk vector calculation unit for calculating a vector connecting the marked markers as an upper trunk vector which is a vector indicating the direction of the upper trunk, and a marker affixed to the lower edge of the right and left lowest auxiliary cartilage A lower trunk vector calculation unit that calculates a vector connecting the two as a lower trunk vector that is a vector indicating the orientation of the lower trunk, and the calculated upper trunk vector and the lower trunk vector to the horizontal plane of the subject A rotation angle calculation unit that calculates an angle formed by the projected vectors as a rotation angle between the upper trunk and the lower trunk of the subject may be included.

  According to this configuration, the three-dimensional space of the markers affixed to the subject's right and left acicular ridges and the lower edge of the right and left lowest auxiliary cartilage from the distance image, rather than hitting the goniometer to the subject The coordinates inside are calculated. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the rotation angle between the upper trunk and the lower trunk of the subject can be accurately calculated from the coordinates of the plurality of markers.

  Further, the plurality of markers are affixed to the lower edge of the lowest prosthetic cartilage on the right side and the left side of the subject and the upper anterior iliac spine on the right side and the left side. A lower trunk vector calculation unit that calculates a vector connecting the markers attached to the lower edge of the lower auxiliary cartilage as a lower trunk vector that is a vector indicating the direction of the lower trunk, and the right and left upper anterior iliac bones A pelvic vector calculation unit that calculates a vector connecting the markers affixed to the spines as a pelvic vector that is a vector indicating the orientation of the pelvis, and the calculated lower trunk vector and the pelvis vector are projected onto the horizontal plane of the subject A rotation angle calculation unit that calculates an angle formed by the vectors as a rotation angle between the lower trunk of the subject and the pelvis may be included.

  According to this configuration, instead of applying a goniometer to the subject, from the distance image, the tertiary of the marker affixed to the lower edge of the lowest costal cartilage on the right and left side of the subject and the upper anterior iliac spine on the right and left side Coordinates in the original space are calculated. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the rotation angle between the lower trunk of the subject and the pelvis can be accurately calculated from the coordinates of the plurality of markers.

  Preferably, the camera irradiates the subject with light, receives reflected light of the irradiated light, and calculates the distance image by calculating a distance to the subject from a difference between an irradiation start time and a light reception time. Each of the plurality of markers is made of a retroreflective member.

  The retroreflective member has a characteristic of reflecting the light that hits it straight toward the light source. For this reason, the distance image can be accurately calculated. Therefore, a value indicating the posture of the subject can be accurately calculated from the coordinates of the plurality of markers.

  Note that the present invention can be realized not only as an attitude detection apparatus including such a characteristic processing unit, but also as an attitude detection method including steps executed by the characteristic processing unit included in the attitude detection apparatus. Can be realized. Further, it can be realized as a program for causing a computer to function as a characteristic processing unit included in the posture detection apparatus or a program for causing a computer to execute characteristic steps included in a posture detection method. Further, it goes without saying that such a program can be distributed via a computer-readable non-transitory recording medium such as a CD-ROM (Compact Disc-Read Only Memory) or a communication network such as the Internet. .

  ADVANTAGE OF THE INVENTION According to this invention, the attitude | position detection apparatus etc. which can calculate the value which shows a test subject's attitude | position correctly can be provided.

It is a figure for demonstrating the utilization scene of the attitude | position detection system containing an attitude | position detection apparatus. It is a block diagram which shows the functional structure of the attitude | position detection apparatus which concerns on Embodiment 1 of this invention. It is a general-view figure of a range image camera. It is a figure for demonstrating the principle of the distance measurement by a distance image camera. (A) is a figure which shows an example of the image which image | photographed the test subject using the normal camera. (B) is a figure which shows an example of the distance image which image | photographed the same position as (a). It is a figure which shows the state in which the test subject is facing the front. 5 is a flowchart of processing executed by the posture detection apparatus according to the first embodiment. It is a figure which shows the state which the test subject rotated the head to the right limit. It is a flowchart of the process which the attitude | position detection apparatus which concerns on Embodiment 2 of this invention performs. It is a figure which shows the state which the test subject closed both legs. It is a figure which shows the state which the test subject made the right hip joint abduction motion by opening a right leg. It is a block diagram which shows the functional structure of the attitude | position detection apparatus which concerns on Embodiment 3 of this invention. It is a figure for demonstrating the sticking position of a marker. (A) is a figure which shows typically the sticking position of the marker to a test subject. (B) is a figure which shows the curve which passes along the some marker affixed between the spinous process of the 7th cervical spine to the spinous process of the lumbar vertebra. (C) is a figure for demonstrating the calculation method of a trunk inclination | tilt angle, a rear bay index, and a front bay index. It is a flowchart of the process which the attitude | position detection apparatus which concerns on Embodiment 3 of this invention performs. It is a figure which shows an example of a sagittal surface. It is a block diagram which shows the functional structure of the attitude | position detection apparatus which concerns on Embodiment 4 of this invention. It is a figure for demonstrating the sticking position of a marker. It is a figure which shows an example of a front face. It is a figure which shows an example of a horizontal surface. It is a flowchart of the process which the attitude | position detection apparatus which concerns on Embodiment 4 of this invention performs. It is a figure for demonstrating an upper trunk vector, a lower trunk vector, and a pelvis vector. It is a figure for demonstrating the calculation method of the inclination angle between an upper trunk and a lower trunk. It is a figure which shows the state in which the test subject is facing the front. It is a figure which shows the state which the test subject rotated the head to the right limit. It is a figure which shows the test subject of the supine position of the state which closed both legs. It is a figure which shows the test subject of the state which carried out the abduction movement of the right hip joint.

  Hereinafter, an attitude detection apparatus according to the present invention will be described based on embodiments.

(Embodiment 1)
In the first embodiment, a posture detection device that calculates the rotation angle of the cervical spine for the purpose of measuring the range of motion of the joint of the subject will be described.

  FIG. 1 is a diagram for explaining a use scene of an attitude detection system including an attitude detection device.

  The posture detection system includes a posture detection device 100 and a distance image camera 400. The posture detection device 100 measures the distance to the subject and is connected to the distance image camera 400 that can capture the distance image, and acquires the distance image from the distance image camera 400. The posture detection apparatus 100 detects the posture of the person 500 serving as the subject from the acquired distance image. The distance image camera 400 is tilted by a certain tilt angle θ with respect to a plane parallel to the ground, and is disposed at a position where the ground can be photographed from above. The posture detection device 100 is typically realized by a computer including a CPU and a memory, and functions as the posture detection device 100 by operating programs for realizing various processes described later on the CPU. .

  Note that a point on the ground just below the distance image camera 400 is an origin O (0, 0, 0), a horizontal direction is an x-axis direction, a height direction is a y-axis direction, and a depth direction is a z-axis direction. In the following, unless otherwise specified, a three-dimensional coordinate system is defined by the origin O, the x axis, the y axis, and the z axis. However, the method for defining the three-dimensional coordinate system is not limited to this.

  FIG. 2 is a block diagram showing a functional configuration of the posture detection apparatus according to Embodiment 1 of the present invention.

  The posture detection apparatus 100 includes a distance image acquisition unit 102, a coordinate calculation unit 104, and a posture calculation unit 106.

  The distance image acquisition unit 102 is a processing unit that acquires a distance image in which the luminance value in each pixel indicates the distance from the camera to the subject.

  The camera is a distance image camera that can measure the distance to the subject, irradiates the subject with light, receives the reflected light of the irradiated light, and determines the distance to the subject from the difference between the irradiation start time and the light reception time. A distance image is generated by calculating. The distance image acquisition unit 102 is connected to the distance image camera and acquires a distance image captured by the distance image camera.

FIG. 3 is an overview of the range image camera.
The range image camera 400 includes a plurality of LEDs (Light Emitting Diodes) 402 and lenses 404 regularly arranged on the front surface thereof. Light is emitted from the LED 402 toward the subject, and the reflected light is collected on the lens 404.

FIG. 4 is a diagram for explaining the principle of distance measurement by the distance image camera 400.
The light 403 emitted from the plurality of LEDs 402 at the same time is reflected by the subject (for example, a person 500), and the reflected light 405 is collected by the lens 404. At this time, the time from when the light 403 is emitted from the LED 402 until the reflected light 405 reaches the lens 404 varies depending on the position of the subject. That is, the closer the subject is to the distance image camera 400, the shorter the arrival time of the reflected light 405, and the longer the subject is to the distance image camera 400, the longer the arrival time of the reflected light 405. The distance image camera 400 outputs the distance to the subject for each pixel by measuring the arrival time for each pixel. That is, the distance image camera 400 outputs a distance image in which the distance to the subject is represented by the luminance value in the pixel. FIG. 5A is a diagram illustrating an example of an image obtained by photographing a subject using a normal camera. As shown in FIG. 5A, the image includes two persons as subjects. FIG. 5B is a diagram illustrating an example of a distance image obtained by photographing the same position as in FIG. In the distance image, the closer the distance to the distance image camera 400 is, the smaller the luminance value (the luminance is darker), and the longer the distance, the larger the luminance value (the luminance is brighter). As shown in FIG. 5B, it can be seen that the luminance value of the front person is smaller than that of the rear person.

  Referring to FIG. 2 again, the coordinate calculation unit 104 is a processing unit that calculates the coordinates in the three-dimensional space of a plurality of markers attached to the subject based on the distance image acquired by the distance image acquisition unit 102. is there.

FIG. 6 is a diagram for explaining a marker attaching position.
The plurality of markers include markers 112 and 114 attached to the right and left shoulder ridges of the subject 110, a marker 116 attached to the top of the head, and a marker 118 attached between the eyebrows. Each marker consists of a retroreflective member.

  Referring to FIG. 2 again, the posture calculation unit 106 is a processing unit that calculates a value indicating the posture of the subject from the coordinates of the plurality of markers calculated by the coordinate calculation unit 104.

  Specifically, the posture calculation unit 106 pastes the straight line connecting the marker pasted on the right and left shoulder ridges between the state where the subject is facing the front and the state where the subject is turning his head to the top of the head. The difference between the angle formed by the marker and the straight line connecting the marker affixed between the eyebrows is calculated as the rotation angle of the cervical spine.

  FIG. 7 is a flowchart of processing executed by posture detection apparatus 100 according to Embodiment 1 of the present invention.

  The distance image acquisition unit 102 acquires a distance image captured by the distance image camera 400 (S2). That is, the distance image acquisition unit 102 is a state where the subject 110 is photographed with the subject 110 facing the front as shown in FIG. 6 and the state where the subject 110 rotates the head to the right limit as shown in FIG. The distance image photographed in is acquired.

  The coordinate calculation unit 104 calculates the coordinates in the three-dimensional space of a plurality of markers attached to the subject based on the distance image acquired by the distance image acquisition unit 102 (S4). That is, the coordinates in the three-dimensional space of the markers 112 to 118 in the state where the subject 110 shown in FIG. 6 is facing the front, and the marker in the state where the subject 110 shown in FIG. The coordinates in the three-dimensional space 112 to 118 are calculated. 6 and 8, it is assumed that the subject 110 faces the distance image camera 400. For this reason, in the distance image, the coordinate calculation unit 104 determines that the marker shown on the left is the marker 112, determines the marker shown on the right is the marker 114, and is on the top. Markers are distinguished from each other by determining the marker 116 as a marker and the other markers as markers 118. However, the positional relationship between the subject 110 and the distance image camera 400 is not limited to this, and any positional relationship can be used as long as the coordinate calculation unit 104 can determine the position of each marker. Also good.

  The posture calculation unit 106 includes a straight line connecting a marker affixed to the right and left acromials in a state in which the subject is facing the front and a state in which the subject rotates the head, a marker affixed to the top of the head, and a space between the eyebrows The difference between the angles formed by the straight line connecting the markers affixed to is calculated as the rotation angle of the cervical spine (S6). That is, the posture calculation unit 106 has a straight line connecting the marker 112 and the marker 114 and a straight line connecting the marker 116 and the marker 118 in the three-dimensional space in a state where the subject 110 shown in FIG. Calculate the angle between the two. In addition, the posture calculation unit 106, in a state where the subject 110 illustrated in FIG. 8 rotates his head to the right limit, in the three-dimensional space, a straight line connecting the marker 112 and the marker 114, the marker 116 and the marker 118, The angle formed by the straight line connecting is calculated. The posture calculation unit 106 calculates the rotation angle of the cervical spine by calculating the difference between the two calculated angles. Specifically, the absolute value of the difference between the two angles may be calculated as the rotation angle of the cervical spine.

  For example, the coordinates of the markers 112, 114, 116, and 118 in the three-dimensional space are respectively (x1, y1, z1), (x2, y2, z2), (x3, y3, z3), and (x4, y4). , Z4). An angle ψ formed by a straight line connecting the marker 112 and the marker 114 and a straight line connecting the marker 116 and the marker 118 is a vector having the position of the marker 112 as a start point and the position of the marker 114 as an end point, and the position of the marker 116. It is equal to the angle ψ formed by the vector having the start point and the marker 118 as the end point. That is, the angle ψ can be expressed by the following (Equation 1). The angle ψ is calculated for each of the state in which the subject 110 faces the front and the state in which the subject 110 rotates the head to the right limit, and by calculating the difference between the two calculated angles, the rotation angle of the cervical spine is calculated. Can be calculated.

  As described above, according to the first embodiment, the goniometer is not applied to the subject, but the coordinates of the plurality of markers in the three-dimensional space are calculated from the distance image. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, a value indicating the posture of the subject can be accurately calculated from the coordinates of the plurality of markers. Specifically, the coordinates in the three-dimensional space of the markers attached to the right and left shoulder ridges, the top of the head, and the space between the eyebrows are calculated from the distance image. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the rotation angle of the subject's cervical spine can be accurately calculated from the coordinates of the plurality of markers.

  In addition, the retroreflective member has a characteristic of reflecting the hit light straight toward the light source. For this reason, the distance image can be accurately calculated. Therefore, a value indicating the posture of the subject can be accurately calculated from the coordinates of the plurality of markers.

  In the first embodiment, the posture detection device that calculates the rotation angle of the cervical vertebra when the test subject rotates to the right side has been described. However, the rotation angle of the cervical spine when the test subject rotates to the left side is also described. It can be calculated in the same manner as in the case where the rightward rotation is performed.

(Embodiment 2)
In the second embodiment, a posture detection device that calculates an abduction angle when the hip joint is abducted for the purpose of measuring the range of motion of the subject's joint will be described.

  The configuration of the posture detection system and the posture detection system including the posture detection device according to the second embodiment are the same as those described with reference to FIGS. 2 and 1 in the first embodiment. For this reason, in the following description, it demonstrates focusing on a different part from Embodiment 1, and does not repeat description about the same part.

  In the first embodiment, the posture calculation unit 106 calculates the rotation angle of the cervical spine, but in the second embodiment, the posture calculation unit 106 calculates the abduction angle when the hip joint is abducted.

  FIG. 9 is a flowchart of processing executed by posture detection apparatus 200 according to Embodiment 2 of the present invention.

  The distance image acquisition unit 102 acquires a distance image captured by the distance image camera 400 (S2). In other words, the distance image acquisition unit 102 removes the right hip joint when the subject 120 opens the right leg as shown in FIG. 10B and the distance image taken with the subject 120 closed as shown in FIG. 10A. A distance image photographed in a state of rolling is acquired. As shown in FIGS. 10A and 10B, it is assumed that the subject 120 is sleeping on the bed, and markers 122 and 124 are respectively attached to the right and left upper anterior iliac spines of the subject 120 so that the right leg patella It is assumed that a marker 126 is attached to (preferably the center position of the patella). Each marker consists of a retroreflective member.

  The coordinate calculation unit 104 calculates the coordinates in the three-dimensional space of a plurality of markers attached to the subject based on the distance image acquired by the distance image acquisition unit 102 (S8). That is, the coordinates in the three-dimensional space of the markers 122 to 126 when the subject 120 shown in FIG. 10A closes both legs, and the marker 122 when the subject 120 shown in FIG. 10B abducts the right hip joint. To 126 coordinates in a three-dimensional space. 10A and 10B, the subject 120 is in a supine position, and in the distance image, the left leg is on the lower side, the right leg is on the upper side, the toes are on the left side, and the waist is on the right side. It shall be reflected. Therefore, the coordinate calculation unit 104 determines that the leftmost marker in the distance image is the marker 126, the lowest marker is the marker 124, and the other markers are the markers 122. By distinguishing, the marker is distinguished. However, the positional relationship between the subject 120 and the distance image camera 400 is not limited to this, and any positional relationship can be used as long as the coordinate calculation unit 104 can determine the position of each marker. Also good.

  The posture calculation unit 106 includes a straight line connecting a marker attached to the right and left upper anterior iliac spines in a state in which the subject 120 closes both legs and a state in which the right hip joint is abducted, and a right upper The difference in angle formed by the straight line connecting the marker attached to the anterior iliac spine is calculated as the abduction angle when the hip joint is abducted (S10). That is, the posture calculation unit 106 has a straight line connecting the marker 122 and the marker 124 and a straight line connecting the marker 122 and the marker 126 in the three-dimensional space when the subject 120 shown in FIG. Calculate the angle formed by. In addition, the posture calculation unit 106, in a state where the subject 120 illustrated in FIG. 10B has abducted the right hip joint, in the three-dimensional space, the straight line connecting the marker 122 and the marker 124, the marker 122 and the marker 126, The angle formed by the straight line connecting is calculated. The posture calculation unit 106 calculates the abduction angle when the right hip joint is abducted by calculating the difference between the two calculated angles. Specifically, the absolute value of the difference between the two angles may be calculated as the abduction angle.

  For example, the coordinates of 122, 124 and 126 in the three-dimensional space are (x5, y5, z5), (x6, y6, z6) and (x7, y7, z7). An angle φ formed by a straight line connecting the marker 122 and the marker 124 and a straight line connecting the marker 122 and the marker 126 is a vector having the position of the marker 122 as a start point and the position of the marker 124 as an end point, and the position of the marker 122. It is equal to the angle φ formed by the vector having the start point and the position of the marker 126 as the end point. That is, the angle φ can be expressed by the following (Formula 2). This angle φ is calculated when the subject 120 closes both legs and the right hip joint is abducted, and the right hip joint is abducted by calculating the difference between the two calculated angles. The abduction angle can be calculated.

  As described above, according to the second embodiment, the marker affixed to the right anterior iliac spine on the right and left sides of the subject and the patella of the right leg from the distance image, instead of applying the goniometer to the subject. The coordinates in the three-dimensional space are calculated. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the abduction angle when the subject's right hip joint is abducted can be accurately calculated from the coordinates of the plurality of markers.

  In the second embodiment, the posture detecting device that calculates the abduction angle when the subject opens the right leg and abducts the right hip joint has been described. However, when the subject opens the left leg, the left hip joint is calculated. The abduction angle when the abduction movement is performed can be calculated in the same manner as the abduction movement of the right hip joint.

(Embodiment 3)
In the third embodiment, a posture detecting device for calculating a trunk inclination angle, a rear bay index, and a front bay index, which will be described later, for the purpose of measuring the degree of bending of the spinal column will be described.

  The configuration of the attitude detection system including the attitude detection device according to the third embodiment is the same as that described with reference to FIG. 1 in the first embodiment. In the following description, portions different from those in Embodiments 1 and 2 will be mainly described, and description of similar portions will not be repeated.

  FIG. 11 is a block diagram showing a functional configuration of the posture detection apparatus according to the third embodiment of the present invention.

  The posture detection apparatus 200 includes a distance image acquisition unit 102, a coordinate calculation unit 204, and a posture calculation unit 206.

  The distance image acquisition unit 102 is a processing unit that acquires a distance image in which the luminance value in each pixel indicates the distance from the camera to the subject.

  The coordinate calculation unit 204 is a processing unit that calculates coordinates in a three-dimensional space of a plurality of markers attached to the subject based on the distance image acquired by the distance image acquisition unit 102.

FIG. 12 is a diagram for explaining a marker attaching position.
The plurality of markers are a plurality of markers 222, 223 and 224 attached between the seventh cervical spinous process and the spinous process of the lumbar spine, and markers attached to the right and left upper posterior iliac spines, respectively. 226 and marker 228. Each marker consists of a retroreflective member. FIG. 13A is a diagram schematically showing the position where the marker is attached to the subject 220, and is a view of the subject 220 seen from the side. FIG. 13B is a diagram showing a curve 230 passing through a plurality of markers 222 and 223 attached between the seventh cervical spinous process and the spinous process of the lumbar spine.

  Referring to FIG. 11 again, posture calculation unit 206 includes trunk inclination angle calculation unit 208, first calculation unit 211, second calculation unit 212, and third calculation unit 213.

  Referring to FIG. 13C, the trunk inclination angle calculation unit 208 includes a marker 222 attached to the seventh cervical spinous process of the subject 220 and a marker 226 attached to the right and left upper posterior iliac spines. And the angle formed by the straight line 232 connecting the midpoint 240 of 228 and the barycentric line 234 of the subject 220 is calculated as the trunk inclination angle γ. The barycentric line 234 is a perpendicular line dropped from the barycenter of the subject 220 perpendicularly to the ground. In addition, this center-of-gravity line 234 can be assumed to be a perpendicular line dropped from the midpoint 240 of the markers 226 and 228 perpendicularly to the ground, for example.

  The first calculation unit 211, the second calculation unit 212, and the third calculation unit 213 are processing units for calculating the rear bay index and the front bay index. With reference to FIG.13 (c), the process which the 1st calculation part 211, the 2nd calculation part 212, and the 3rd calculation part 213 perform is demonstrated.

  From the straight line 232 connecting the marker 222 affixed to the seventh cervical spine process and the midpoint 240 of the markers 226 and 228 affixed to the right and left superior iliac spines, respectively, A maximum value h1 of the distance from the cervical spine process to the thoracic vertebral curve 230 among the curves 230 passing through the plurality of markers 222 to 224 attached between the spinous process of the lumbar spine is calculated. The first calculation unit 211 further calculates a maximum value h2 of the distance from the straight line 232 to the curve 230 of the lumbar portion of the curve 230.

  The second calculator 212 calculates the distance l1 from the marker 222 attached to the seventh cervical spinous process to the point 227 where the straight line 232 and the curve 230 intersect. The second calculator 212 further calculates a distance l2 from the point 227 where the straight line 232 and the curve 230 intersect to the midpoint 240.

  The third calculation unit 213 calculates the value obtained by dividing the maximum value h1 calculated by the first calculation unit 211 by the distance l1 calculated by the second calculation unit 212, thereby indicating the degree of the rear bay of the subject 220. Calculate the Bay Index. The third calculation unit 213 further calculates a value of the front bay of the subject 220 by calculating a value obtained by dividing the maximum value h2 calculated by the first calculation unit 211 by the distance l2 calculated by the second calculation unit 212. Maewan index is calculated.

  FIG. 14 is a flowchart of processing executed by posture detection apparatus 200 according to Embodiment 3 of the present invention.

  The distance image acquisition unit 102 acquires a distance image captured by the distance image camera 400 (S2). That is, the distance image acquisition unit 102 includes a plurality of markers 222, 223, and 224 attached between the seventh cervical spinous process and the lumbar spinous process of the subject 220 as shown in FIG. The distance image camera 400 acquires a distance image obtained by photographing the back of the subject 220 so that the marker 226 and the marker 228 attached to the posterior iliac spine are captured.

  The coordinate calculation unit 204 calculates the coordinates in the three-dimensional space of a plurality of markers attached to the subject 220 based on the distance image acquired by the distance image acquisition unit 102 (S21). That is, the coordinates in the three-dimensional space of the markers 222, 223, 224, 226 and 228 of the subject 220 shown in FIG. 12 are calculated. As shown in FIG. 12, it is assumed that the subject 220 has his back facing the distance image camera 400. For this reason, the coordinate calculation unit 204 determines that the marker appearing at the top in the distance image is the marker 222, and of the two markers from the bottom, the marker appearing on the left is determined as the marker 228, and the right side Marker 226 is determined as marker 226, the third marker from the bottom is determined as marker 224, and the other markers are determined as marker 223, thereby distinguishing the markers. However, the positional relationship between the subject 220 and the distance image camera 400 is not limited to this, and any positional relationship can be used as long as the coordinate calculation unit 204 can determine the position of each marker. Also good.

  The trunk inclination angle calculation unit 208 connects straight lines between the marker 222 attached to the seventh cervical spinous process of the subject 220 and the midpoint 240 of the markers 226 and 228 attached to the right and left upper posterior iliac spines, respectively. An angle formed by H.232 and the center of gravity line 234 of the subject 220 is calculated as the trunk inclination angle γ (S22). The subject 220 can determine the degree of forward inclination or the degree of backward inclination based on the trunk inclination angle γ.

  From the straight line 232 connecting the marker 222 affixed to the seventh cervical spine process and the midpoint 240 of the markers 226 and 228 affixed to the right and left superior iliac spines, respectively, The maximum value h1 of the distance from the cervical spine process to the curve 230 of the thoracic vertebra part among the curves 230 passing through the plurality of markers 222 to 224 attached between the spinous process of the lumbar spine is calculated (S23).

  The second calculator 212 calculates the distance l1 from the marker 222 attached to the seventh cervical spinous process to the point 227 where the straight line 232 and the curve 230 intersect (S24).

  The third calculation unit 213 calculates the value obtained by dividing the maximum value h1 calculated by the first calculation unit 211 by the distance l1 calculated by the second calculation unit 212, thereby indicating the degree of the rear bay of the subject 220. The Bay Index is calculated (S25).

  The first calculation unit 211 calculates the maximum value h2 of the distance from the straight line 232 to the curve 230 of the lumbar portion of the curve 230 (S26).

  The second calculator 212 calculates the distance l2 from the point 227 where the straight line 232 and the curve 230 intersect to the midpoint 240 (S27).

  The third calculator 213 indicates the degree of the front bay of the subject 220 by calculating a value obtained by dividing the maximum value h2 calculated by the first calculator 211 by the distance l2 calculated by the second calculator 212. The front bay index is calculated (S28).

  As described above, according to the third embodiment, the goniometer is not applied to the subject, but is attached to the subject's seventh cervical spinous process and the right and left upper posterior iliac spines from the distance image. The coordinates of the marker in the three-dimensional space are calculated. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the trunk inclination angle of the subject can be accurately calculated from the coordinates of the plurality of markers.

  In addition, from a distance image, a three-dimensional space of a plurality of markers affixed between the spinous process of the subject's seventh cervical spine and a lumbar spine and two markers affixed to the right and left upper iliac spines The coordinates inside are calculated. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the rear bay index indicating the degree of the rear bay of the subject can be accurately calculated from the coordinates of the plurality of markers.

  Further, from the distance image, a three-dimensional space of a plurality of markers attached from the seventh cervical spinous process of the subject to the spinous process of the lumbar spine and two markers attached to the right and left upper iliac spines The coordinates inside are calculated. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the front bay index indicating the degree of the front bay of the subject can be accurately calculated from the coordinates of the plurality of markers.

  In the third embodiment, the trunk inclination angle, the rear bay index, and the front bay index are calculated. However, any one or two of the three may be calculated. . In order to calculate the trunk inclination angle, the marker 222 attached to the seventh cervical spine process of the subject and the markers 226 and 228 attached to the right and left upper posterior iliac spines respectively in the three-dimensional space. It is only necessary that the coordinates of can be calculated. That is, the other markers 223 and 224 are not necessary.

  In Embodiment 3, the calculation performed by the posture calculation unit 206 is performed using coordinates in the three-dimensional space. However, the calculation may be performed using coordinates obtained by projecting each coordinate onto a sagittal plane. . FIG. 15 is a diagram for explaining a sagittal plane. The sagittal plane 346 is a plane that cuts the subject 220 symmetrically. That is, FIG. 13A can be considered to indicate the position of the marker projected on the sagittal plane 346.

(Embodiment 4)
In the fourth embodiment, a posture detection apparatus for calculating a tilt angle and a rotation angle, which will be described later, is described for the purpose of measuring trunk deformation seen in a child with cerebral palsy.

  The configuration of the posture detection system including the posture detection device according to the fourth embodiment is the same as that described with reference to FIG. 1 in the first embodiment. In the following description, parts different from those in the first to third embodiments will be mainly described, and description of the same parts will not be repeated.

  FIG. 16 is a block diagram illustrating a functional configuration of the posture detection apparatus according to the fourth embodiment of the present invention.

  The posture detection device 300 includes a distance image acquisition unit 102, a coordinate calculation unit 304, and a posture calculation unit 306.

  The distance image acquisition unit 102 is a processing unit that acquires a distance image in which the luminance value in each pixel indicates the distance from the camera to the subject.

  The coordinate calculation unit 304 is a processing unit that calculates coordinates in a three-dimensional space of a plurality of markers attached to the subject based on the distance image acquired by the distance image acquisition unit 102.

FIG. 17 is a diagram for explaining a marker attaching position.
The plurality of markers include markers 322 and 324 attached to the right and left acromial ridges of the subject 320, markers 326 and 328 attached to the lower edge of the right and left lowest auxiliary cartilage, respectively, and the right and left sides. Markers 330 and 332 attached to the upper anterior iliac spine, respectively. Each marker consists of a retroreflective member. FIG. 17 shows the subject 320 in a skeletal view, but in actuality, the marker is affixed on the skin or clothes.

  Referring to FIG. 16 again, the posture calculation unit 306 includes an upper trunk vector calculation unit 308, a lower trunk vector calculation unit 310, a pelvis vector calculation unit 312, an inclination angle calculation unit 314, and a rotation angle calculation unit. 316.

  The upper trunk vector calculation unit 308 calculates a vector connecting the markers 322 and 324 attached to the right and left shoulder ridges as an upper trunk vector that is a vector indicating the direction of the upper trunk.

  The lower trunk vector calculation unit 310 calculates a vector connecting the markers 326 and 328 attached to the lower edges of the right and left lowermost auxiliary cartilages as a lower trunk vector which is a vector indicating the direction of the lower trunk. To do.

  The pelvic vector calculation unit 312 calculates a vector connecting the markers 330 and 332 attached to the right and left upper anterior iliac spines as a pelvic vector that is a vector indicating the orientation of the pelvis.

  The inclination angle calculation unit 314 uses, as an inclination angle between the upper trunk and the lower trunk of the subject, an angle formed by the vectors obtained by projecting the calculated upper trunk vector and lower trunk vector onto the subject's frontal plane. calculate. FIG. 18 is a diagram illustrating an example of the front face value. The frontal plane 342 is a plane that cuts the subject 320 back and forth, and is a plane perpendicular to the sagittal plane 346. The inclination angle calculation unit 314 further calculates an angle formed by the vectors obtained by projecting the calculated lower trunk vector and pelvic vector onto the subject's frontal plane as an inclination angle between the lower trunk and the pelvis of the subject. .

  The rotation angle calculation unit 316 calculates an angle formed by the vectors obtained by projecting the calculated upper trunk vector and lower trunk vector onto the horizontal plane of the subject as the rotation angle between the upper trunk and the lower trunk of the subject. To do. FIG. 19 is a diagram illustrating an example of a horizontal plane. The horizontal plane 344 is a plane that is parallel to the floor and orthogonal to the frontal plane 342 and the sagittal plane 346. The rotation angle calculation unit 316 further calculates an angle formed by the vectors obtained by projecting the calculated lower trunk vector and pelvis vector onto the horizontal plane of the subject as the rotation angle between the lower trunk and the pelvis of the subject.

  In the fourth embodiment, the three-dimensional coordinate system is defined as follows. That is, the frontal plane 342 shown in FIG. 18 is a yz plane, and the horizontal plane 344 shown in FIG. 19 is an xy plane. Further, the position of the ground is the origin of the line (z axis) where the frontal plane 342 and the sagittal plane 346 (xz plane) shown in FIG. 15 intersect. A three-dimensional coordinate system that satisfies such conditions is assumed.

  FIG. 20 is a flowchart of processing executed by posture detection apparatus 300 according to Embodiment 4 of the present invention.

  The distance image acquisition unit 102 acquires a distance image captured by the distance image camera 400 (S2). That is, as shown in FIG. 17, the distance image acquisition unit 102 is attached to the markers 322 and 324 respectively attached to the right and left shoulder ridges of the subject 320 and the lower edge of the rightmost and leftmost lowest auxiliary cartilage. The distance image camera 400 acquires a distance image obtained by photographing the subject 320 so that the markers 326 and 328 and the markers 330 and 332 attached to the right and left upper anterior iliac spines, respectively, are shown.

  The coordinate calculation unit 304 calculates the coordinates in the three-dimensional space of a plurality of markers attached to the subject 320 based on the distance image acquired by the distance image acquisition unit 102 (S31). That is, the coordinates in the three-dimensional space of the markers 322, 324, 326, 328, 330 and 332 of the subject 320 shown in FIG. 17 are calculated. As shown in FIG. 17, it is assumed that the subject 320 faces the front of the distance image camera 400. For this reason, the coordinate calculation unit 304 determines that the left marker among the first and second markers from the top in the distance image is the marker 322, and the right marker is the marker 324. In addition, the coordinate calculation unit 304 determines that the left marker among the third and fourth markers from the top in the distance image is the marker 326 and the right marker is the marker 328. Also, the coordinate calculation unit 304 determines that the left marker among the markers appearing first or second from the bottom in the distance image is the marker 330 and the right marker is the marker 332. However, the positional relationship between the subject 320 and the distance image camera 400 is not limited to this, and any positional relationship can be used as long as the coordinate calculation unit 304 can determine the position of each marker. Also good.

  The upper trunk vector calculation unit 308 calculates a vector connecting the markers 322 and 324 attached to the right and left shoulder ridges as an upper trunk vector which is a vector indicating the direction of the upper trunk (S32). That is, as shown in FIG. 21, in the three-dimensional space, a vector having the position of the marker 324 as the start point and the position of the marker 322 as the end point is calculated as the upper trunk vector 334.

  The lower trunk vector calculation unit 310 calculates a vector connecting the markers 326 and 328 attached to the lower edges of the right and left lowermost auxiliary cartilages as a lower trunk vector which is a vector indicating the direction of the lower trunk. (S33). That is, as shown in FIG. 21, in the three-dimensional space, a vector whose start point is the position of the marker 328 and whose end point is the position of the marker 326 is calculated as the lower trunk vector 336.

  The pelvis vector calculation unit 312 calculates a vector connecting the markers 330 and 332 attached to the right and left upper anterior iliac spines as a pelvis vector that is a vector indicating the orientation of the pelvis (S34). That is, as shown in FIG. 21, a vector having the position of the marker 332 as the start point and the position of the marker 330 as the end point is calculated as a pelvic vector 338 in the three-dimensional space.

  The inclination angle calculation unit 314 determines an angle formed by the vectors obtained by projecting the calculated upper trunk vector 334 and lower trunk vector 336 on the subject's frontal plane, and the inclination between the upper trunk and the lower trunk of the subject. The angle α is calculated (S35). For example, the coordinates of the markers 324, 322, 328 and 326 in the three-dimensional space are respectively (X1, Y1, Z1), (X2, Y2, Z2), (X3, Y3, Z3) and (X4, Y4). , Z4). Then, the upper trunk vector 334 is represented by (X2-X1, Y2-Y1, Z2-Z1), and the lower trunk vector 336 is represented by (X4-X3, Y4-Y3, Z4-Z3). As shown in FIG. 22, a vector obtained by projecting the upper trunk vector 334 onto the frontal plane 342 is referred to as a vector U_tr, and a vector obtained by projecting the lower trunk vector 336 onto the frontal plane 342 is referred to as a vector L_tr. The inclination angle calculation unit 314 calculates an inclination angle α between the upper trunk and the lower trunk of the subject according to the following (Equation 3). However, U_tr = (0, Y2-Y1, Z2-Z1) and L_tr = (0, Y4-Y3, Z4-Z3).

  The inclination angle calculation unit 314 further determines the angle formed by the vectors obtained by projecting the calculated lower trunk vector 336 and pelvis vector 338 onto the subject's frontal plane, and the inclination angle β between the lower trunk and the pelvis of the subject. (S35). For example, the coordinates of the markers 332 and 330 in the three-dimensional space are (X5, Y5, Z5) and (X6, Y6, Z6), respectively. Then, the pelvic vector 338 is represented by (X6-X5, Y6-Y5, Z6-Z5). Assuming that a vector obtained by projecting the pelvic vector 338 onto the frontal plane 342 is P_tr, the inclination angle calculation unit 314 calculates the inclination angle β between the lower trunk of the subject and the pelvis according to the following (Equation 4). However, P_tr = (0, Y6-Y5, Z6-Z5).

  The rotation angle calculation unit 316 calculates the angle formed by the vectors obtained by projecting the calculated upper trunk vector 334 and lower trunk vector 336 on the horizontal plane of the subject, and the rotation angle between the upper trunk and the lower trunk of the subject. Calculated as ρ (S36). For example, a vector obtained by projecting the upper trunk vector 334 onto the horizontal plane 344 is U_tr2, and a vector obtained by projecting the lower trunk vector 336 onto the horizontal plane 344 is L_tr2. The rotation angle calculation unit 316 calculates the rotation angle ρ between the upper trunk and the lower trunk of the subject according to the following (Formula 5). However, U_tr2 = (X2-X1, Y2-Y1,0) and L_tr2 = (X4-X3, Y4-Y3, 0).

  The rotation angle calculation unit 316 further sets the angle formed by the vectors obtained by projecting the calculated lower trunk vector 336 and pelvis vector 338 onto the horizontal plane of the subject as the rotation angle σ between the lower trunk and the pelvis of the subject. Calculate (S36). For example, a vector obtained by projecting the pelvic vector 338 onto the horizontal plane 344 is P_tr2. The rotation angle calculation unit 316 calculates the rotation angle σ between the lower trunk of the subject and the pelvis according to the following (Equation 6). However, P_tr2 = (X6-X5, Y6-Y5, 0).

  As described above, according to the fourth embodiment, the goniometer is not applied to the subject, but from the distance image, the right and left shoulder ridges of the subject and the lower edge of the lowermost auxiliary cartilage on the right and left sides. The coordinates of the attached marker in the three-dimensional space are calculated. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the inclination angle between the upper trunk and the lower trunk of the subject and the rotation angle between the upper trunk and the lower trunk of the subject can be accurately calculated from the coordinates of the plurality of markers.

  In addition, the coordinates in the three-dimensional space of the markers affixed to the lower edge of the lowermost auxiliary cartilage on the right side and the left side of the subject and the upper anterior iliac spine on the right side and the left side are calculated from the distance image. For this reason, the coordinate of each marker can be calculated | required correctly. Therefore, the inclination angle between the lower trunk of the subject and the pelvis and the rotation angle between the lower trunk of the subject and the pelvis can be accurately calculated from the coordinates of the plurality of markers.

  In the fourth embodiment, the inclination angle between the upper trunk and the lower trunk of the subject, the inclination angle between the lower trunk and the pelvis, the rotation angle between the upper trunk and the lower trunk, Although the rotation angle between the lower trunk and the pelvis is calculated, one to three of the four angles may be calculated.

  To calculate the angle of inclination between the upper and lower trunks of the subject or the rotation angle between the upper and lower trunks, markers attached to the right and left shoulder ridges of the subject, respectively. It is only necessary to be able to calculate the coordinates in the three-dimensional space between 322 and 324 and the markers 326 and 328 attached to the lower edges of the right and left lowest auxiliary cartilages, respectively. That is, the other markers 330 and 332 are not necessary.

  To calculate the inclination angle between the lower trunk and the pelvis of the subject or the rotation angle between the lower trunk and the pelvis, paste them on the lower edge of the lowest prosthesis on the right and left sides of the subject, respectively. It is only necessary to be able to calculate the coordinates in the three-dimensional space between the markers 326 and 328 and the markers 330 and 332 attached to the right and left upper anterior iliac spines, respectively. That is, the other markers 322 and 324 are not necessary.

  As described above, the attitude detection device according to the embodiment of the present invention has been described, but the present invention is not limited to this embodiment.

  For example, each of the above devices may be specifically configured as a computer system including a microprocessor, ROM, RAM, hard disk drive, display unit, keyboard, mouse, and the like. A computer program is stored in the RAM or hard disk drive. Each device achieves its functions by the microprocessor operating according to the computer program. Here, the computer program is configured by combining a plurality of instruction codes indicating instructions for the computer in order to achieve a predetermined function.

  Furthermore, some or all of the constituent elements constituting each of the above-described devices may be configured by a single system LSI (Large Scale Integration). The system LSI is an ultra-multifunctional LSI manufactured by integrating a plurality of components on a single chip, and specifically, a computer system including a microprocessor, ROM, RAM, and the like. . A computer program is stored in the RAM. The system LSI achieves its functions by the microprocessor operating according to the computer program.

  Furthermore, some or all of the constituent elements constituting each of the above-described devices may be configured from an IC card that can be attached to and detached from each device or a single module. The IC card or module is a computer system that includes a microprocessor, ROM, RAM, and the like. The IC card or the module may include the super multifunctional LSI described above. The IC card or the module achieves its function by the microprocessor operating according to the computer program. This IC card or this module may have tamper resistance.

  Further, the present invention may be the method described above. Further, the present invention may be a computer program that realizes these methods by a computer, or may be a digital signal composed of the computer program.

  Furthermore, the present invention provides a non-transitory recording medium capable of reading the computer program or the digital signal, such as a flexible disk, a hard disk, a CD-ROM, an MO, a DVD, a DVD-ROM, a DVD-RAM, a BD ( It may be recorded on a Blu-ray Disc (registered trademark), a semiconductor memory, or the like. The digital signal may be recorded on these non-temporary recording media.

  In the present invention, the computer program or the digital signal may be transmitted via an electric communication line, a wireless or wired communication line, a network represented by the Internet, a data broadcast, or the like.

  The present invention may be a computer system including a microprocessor and a memory, wherein the memory stores the computer program, and the microprocessor operates according to the computer program.

  Further, by recording the program or the digital signal on the non-temporary recording medium and transferring it, or transferring the program or the digital signal via the network or the like, another independent computer It may be implemented by the system.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The present invention can be applied to a posture detection device, and in particular to a posture detection device that can detect the posture of a subject based on a distance image obtained from a distance image camera.

100, 200, 300 Posture detection device 102 Distance image acquisition unit 104, 204, 304 Coordinate calculation unit 106, 206, 306 Posture calculation unit 110, 120, 220, 320 Subject 112, 114, 116, 118, 122, 124, 126 , 222, 223, 224, 226, 228, 322, 324, 326, 328, 330, 332 Marker 208 Trunk angle calculation unit 211 First calculation unit 212 Second calculation unit 213 Third calculation unit 227 Intersection point 230 Curve 232 Straight line 234 Center of gravity line 240 Midpoint 308 Upper trunk vector calculation unit 310 Lower trunk vector calculation unit 312 Pelvic vector calculation unit 314 Inclination angle calculation unit 316 Rotation angle calculation unit 334 Upper trunk vector 336 Lower trunk vector 338 Pelvis Vector 342 front face 344 water Plane 346 Sagittal plane 350 Goniometer 352 First ruler 354 Second ruler 356 Center of rotation 400 Distance image camera 402 LED
403 Light 404 Lens 405 Reflected light 500 People

Claims (13)

A distance image acquisition unit that acquires a distance image in which the luminance value in each pixel indicates the distance from the camera to the subject;
Based on the distance image acquired by the distance image acquisition unit, a coordinate calculation unit that calculates coordinates in a three-dimensional space of a plurality of markers attached to the subject;
A posture detection device comprising: a posture calculation unit that calculates a value indicating the posture of the subject from the coordinates of the plurality of markers calculated by the coordinate calculation unit. The plurality of markers are affixed to the subject's right and left acromion, the parietal region, and between the eyebrows,
The posture calculation unit includes a straight line connecting a marker affixed to the right and left shoulder ridges in a state where the subject is facing the front and a state where the head is rotated, and a marker affixed to the top of the head The posture detection apparatus according to claim 1, wherein a difference between angles formed by a straight line connecting the markers attached between the eyebrows is calculated as a rotation angle of the cervical spine. The plurality of markers are affixed to the right and left upper anterior iliac spines and the right or left patella of the subject,
The posture calculation unit is attached to the right and left upper anterior iliac spines in a state where the subject closes both legs and a state where the leg hip joint with the marker attached to the patella is abducted. A difference between an angle formed by a straight line connecting the marked marker and a straight line connecting the marker affixed to the patella and the marker affixed to the upper anterior iliac spine to which the marker is affixed to the patella, The posture detection device according to claim 1, wherein the angle is calculated as an abduction angle when the abduction movement is performed. The plurality of markers are affixed to the subject's seventh cervical spinous process and the right and left superior posterior iliac spines,
The posture calculation unit includes a straight line connecting a marker affixed to the seventh cervical spine process and a midpoint of the two markers affixed to the right and left upper posterior iliac spines, and a barycentric line of the subject The posture detection apparatus according to claim 1, wherein the angle formed by the angle is calculated as a trunk inclination angle. The plurality of markers includes a plurality of markers affixed between the seventh cervical spinous process of the subject and the spinous processes of the lumbar vertebrae, and two markers affixed to the right and left upper posterior iliac spines. ,
The posture calculation unit
From the seventh cervical spinous process to the spinous process of the lumbar spine from a straight line connecting the marker affixed to the seventh cervical spine process and the midpoint of the two markers affixed to the right and left upper posterior iliac spines A first calculation unit for calculating a maximum value of a distance to a curve of the thoracic vertebra part among curves passing through the plurality of markers pasted until,
A second calculator that calculates a distance from a marker affixed to the seventh cervical spine process to a point where the straight line and the curve intersect;
A third calculation unit that calculates a rear bay index indicating the degree of the rear bay of the subject by calculating a value obtained by dividing the maximum value calculated by the first calculation unit by the distance calculated by the second calculation unit. The posture detection device according to claim 1. The plurality of markers includes a plurality of markers affixed between the seventh cervical spinous process of the subject and the spinous processes of the lumbar vertebrae, and two markers affixed to the right and left upper posterior iliac spines. ,
The posture calculation unit
From the seventh cervical spinous process to the spinous process of the lumbar spine from a straight line connecting the marker affixed to the seventh cervical spine process and the midpoint of the two markers affixed to the right and left upper posterior iliac spines A first calculation unit that calculates a maximum value of the distance to the curve of the lumbar portion among the curves passing through the plurality of markers pasted until
A second calculation unit for calculating a distance from a point where the straight line and the curve intersect to a midpoint of the two markers attached to the right and left superior posterior iliac spines;
A third calculation unit that calculates a front bay index indicating a degree of the front bay of the subject by calculating a value obtained by dividing the maximum value calculated by the first calculation unit by the distance calculated by the second calculation unit. The posture detection device according to claim 1. The plurality of markers are affixed to the subject's right and left acicular ridges and the lower edge of the right and left lowest prosthetic cartilage,
The posture calculation unit
An upper trunk vector calculation unit that calculates a vector connecting the markers attached to the right and left shoulder ridges as an upper trunk vector that is a vector indicating the direction of the upper trunk;
A lower trunk vector calculation unit for calculating a vector connecting the markers affixed to the lower edge of the right and left lowest auxiliary cartilages as a lower trunk vector that is a vector indicating the direction of the lower trunk;
An angle formed by the vectors obtained by projecting the calculated upper trunk vector and the lower trunk vector onto the frontal plane of the subject is calculated as an inclination angle between the upper trunk and the lower trunk of the subject. The posture detection apparatus according to claim 1, further comprising: The plurality of markers are affixed to the lower edge of the lowest prosthetic cartilage on the right and left sides of the subject and the upper anterior iliac spine on the right and left sides,
The posture calculation unit
A lower trunk vector calculation unit for calculating a vector connecting the markers affixed to the lower edge of the right and left lowest auxiliary cartilages as a lower trunk vector that is a vector indicating the direction of the lower trunk;
A pelvic vector calculation unit that calculates a vector connecting the markers attached to the right and left upper anterior iliac spines as a pelvic vector that is a vector indicating the orientation of the pelvis;
Inclination angle calculation for calculating the angle formed by the vectors obtained by projecting the calculated lower trunk vector and the pelvic vector onto the frontal plane of the subject as the inclination angle between the lower trunk and the pelvis of the subject The posture detection device according to claim 1, further comprising: a unit. The plurality of markers are affixed to the subject's right and left acicular ridges and the lower edge of the right and left lowest prosthetic cartilage,
The posture calculation unit
An upper trunk vector calculation unit that calculates a vector connecting the markers attached to the right and left shoulder ridges as an upper trunk vector that is a vector indicating the direction of the upper trunk;
A lower trunk vector calculation unit for calculating a vector connecting the markers affixed to the lower edge of the right and left lowest auxiliary cartilages as a lower trunk vector that is a vector indicating the direction of the lower trunk;
An angle formed by the vectors obtained by projecting the calculated upper trunk vector and lower trunk vector onto the horizontal plane of the subject is calculated as a rotation angle between the upper trunk and the lower trunk of the subject. The posture detection device according to claim 1, further comprising a rotation angle calculation unit. The plurality of markers are affixed to the lower edge of the lowest prosthetic cartilage on the right and left sides of the subject and the upper anterior iliac spine on the right and left sides,
The posture calculation unit
A lower trunk vector calculation unit for calculating a vector connecting the markers affixed to the lower edge of the right and left lowest auxiliary cartilages as a lower trunk vector that is a vector indicating the direction of the lower trunk;
A pelvic vector calculation unit that calculates a vector connecting the markers attached to the right and left upper anterior iliac spines as a pelvic vector that is a vector indicating the orientation of the pelvis;
A rotation angle calculation unit that calculates an angle formed by the vectors obtained by projecting the calculated lower trunk vector and the pelvis vector onto the horizontal plane of the subject as a rotation angle between the lower trunk and the pelvis of the subject. The posture detection device according to claim 1. The camera irradiates the subject with light, receives reflected light of the irradiated light, generates the distance image by calculating the distance to the subject from the difference between the irradiation start time and the light reception time,
The posture detection device according to claim 1, wherein each of the plurality of markers includes a retroreflective member. A distance image acquisition step for acquiring a distance image in which the luminance value in each pixel indicates the distance from the camera to the subject;
Based on the distance image acquired in the distance image acquisition step, a coordinate calculation step of calculating coordinates in a three-dimensional space of a plurality of markers attached to the subject;
A posture detection method comprising: a posture calculation step of calculating a value indicating the posture of the subject from the coordinates of the plurality of markers calculated in the coordinate calculation step. A distance image acquisition step for acquiring a distance image in which the luminance value in each pixel indicates the distance from the camera to the subject;
Based on the distance image acquired in the distance image acquisition step, a coordinate calculation step of calculating coordinates in a three-dimensional space of a plurality of markers attached to the subject;
A program for causing a computer to execute a posture calculation step of calculating a value indicating the posture of the subject from the coordinates of the plurality of markers calculated in the coordinate calculation step.