JP4102119B2 - Stride measuring device and stride measuring method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a stride measuring device and a stride measuring method for measuring a stride of a subject walking or running on a running surface such as a treadmill.
[0002]
[Prior art]
2. Description of the Related Art In recent years, in sports clubs or the like, a so-called treadmill for performing training and the like by a subject running on a running surface of a belt driven at an appropriate speed (hereinafter simply referred to as “running” includes walking) is provided. It is popular. And the stride of the subject who runs on the running surface of the treadmill is regarded as important as an index for evaluating the running posture of the subject. As an apparatus for measuring such a subject's stride, for example, a device described in Japanese Utility Model Publication No. 7-45239 is known. The device described in this publication obtains the stride from the relationship between the belt driving speed and the time interval at which the foot lands on the running surface.
[0003]
[Problems to be solved by the invention]
However, in the apparatus described in the above publication, since it is necessary to provide a treadmill with a sensor for measuring the driving speed of the belt and detecting the landing of the foot on the running surface, the configuration becomes complicated and high. Cost. Further, since the stride is calculated based on the belt driving speed and the landing time interval, the accuracy of the measured stride may be reduced.
[0004]
Accordingly, the present invention has been made in view of such circumstances, and an object thereof is to provide a stride measuring apparatus and a stride measuring method capable of measuring a stride with high accuracy while having a simple configuration. .
[0005]
[Means for Solving the Problems]
In order to achieve the above object, a stride measuring apparatus according to the present invention is a stride measuring apparatus that measures the stride of a subject who runs or walks on a running surface of a belt driven at a predetermined speed. Based on the image, the position of the one foot landing on the running surface is acquired based on the image, and the position of the other foot landing on the running surface following the one foot is based on the image And calculating the position of one foot relative to the position of the other foot based on the time change of the position of one foot, and using the relative distance between the position of the other foot and the calculated position of the one foot as a stride And a stride calculating means for calculating.
[0006]
According to the stride measuring device according to the present invention, an image including a subject's foot is photographed, and the position of one foot and the position of the other foot sequentially landed on the running surface are acquired based on the image, Calculating the relative distance between the position of the other foot and the calculated position of one foot as a stride by calculating the position of one foot relative to the position of the other foot based on the time change of the position of the other foot Can do. Therefore, it is possible to measure the stride with high accuracy with a simple configuration without using a sensor for detecting the belt driving speed or detecting the landing of the foot on the running surface.
[0007]
In the stride measuring device according to the present invention, the stride calculating means acquires the position of the predetermined part of the subject's foot based on the image, and the subject's foot lands on the running surface based on the time change of the position of the predetermined part. It is preferable to determine whether or not. While the subject's foot is landing on the running surface, for example, the position of the toe, which is a predetermined portion of the subject's foot, has very little displacement in the direction perpendicular to the running surface. Therefore, it is possible to detect the landing of the foot on the traveling surface based on the time change of the position of the predetermined portion of the foot without using a sensor or the like for detecting the landing of the foot on the traveling surface.
[0008]
Further, the stride measuring device according to the present invention includes a position calibration mark that is provided at a predetermined angle with respect to the running surface and follows a change in the inclination of the running surface, and the stride calculating means is configured to display an image based on the position calibration mark in the image. It is preferable to convert the coordinates to coordinates in real space. Even when the traveling surface moves up and down or tilts due to the subject's traveling or other reasons, the installation angle of the position calibration mark with respect to the traveling surface is maintained constant. Therefore, if the coordinates in the image are converted into coordinates in the real space based on the position calibration mark, highly accurate coordinate conversion is possible.
[0009]
Furthermore, the stride measuring device according to the present invention preferably includes posture photographing means for photographing the subject's running posture or walking posture from at least one direction of the subject's front or side. Accordingly, the walking posture or running posture of the subject can be confirmed and evaluated simultaneously with the stride, and the walking posture or the running posture can be efficiently modified.
[0010]
By the way, in order to achieve the above object, the present invention also relates to a stride measurement method, which is a stride measurement method for measuring a stride of a subject running or walking on a running surface of a belt driven at a predetermined speed, A photographing process for photographing an image including a subject's foot, and a position of one foot landed on the running surface is acquired based on the image, and a position of the other foot landed on the running surface following one foot is obtained. Obtained based on the image, calculated the position of one foot relative to the position of the other foot based on the temporal change of the position of one foot, and the relative distance between the position of the other foot and the calculated position of the one foot And a step calculation step for calculating as a step.
[0011]
In the stride calculation step, the position of the predetermined part of the subject's foot is acquired based on the image, and it is determined whether the subject's foot has landed on the running surface based on the time change of the position of the predetermined part. It is preferable to do.
[0012]
In the step calculation step, it is preferable to convert the coordinates in the image into coordinates in the real space based on a position calibration mark that is provided at a predetermined angle with respect to the traveling surface and follows a change in the inclination of the traveling surface. .
[0013]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EMBODIMENTS Hereinafter, a preferred embodiment of a stride measuring apparatus according to the present invention will be described in detail with reference to the drawings.
[0014]
A configuration of the stride measuring apparatus 10 will be described. As shown in FIG. 1, a stride measuring device 10 is a device that measures the stride of a subject S traveling on a running surface 102 of a treadmill 100, and includes position calibration marks 12, 14, a stride video camera (imaging means). ) 16, a computer (step length calculation means) 18, and a display unit 20. The treadmill 100 has a box-shaped cover 104, and a rectangular opening is provided on the upper surface of the cover 104. A pair of rollers 106 and 108 are arranged in parallel in the cover 104, and a belt 110 that is an endless belt is stretched around the rollers 106 and 108. The upper surface of the belt 110 faces the outside from the opening of the cover 104 to form a running surface 102. The roller 106 is rotationally driven by a driving device (not shown), whereby the belt 110 is driven in the arrow A direction at a predetermined speed.
[0015]
The position calibration marks 12 and 14 are provided on the upper surface of the cover 104 of the treadmill 100. The position calibration mark 12 is provided on the upper surface of the cover 104 on the near side of the traveling surface 102, and includes a position calibration mark 12a and a position calibration mark 12b installed at a predetermined distance along the arrow A direction. . In addition, the position calibration mark 14 is provided by the position calibration mark 14a and the position calibration mark 14b which are provided on the upper surface of the cover 104 on the back side of the traveling surface 102 and are installed at a predetermined distance along the arrow A direction. ing.
[0016]
The stride video camera 16 is installed on the front side of the treadmill 100 so that its shooting direction is perpendicular to the arrow A direction, and is adjusted so that the horizontal direction of the image is parallel to the position calibration marks 12 and 14. . This is to facilitate the calculation processing of the computer 18 based on the photographed image. Then, as shown in FIG. 2, the stride video camera 16 captures an image including the foot F of the subject S traveling on the traveling surface 102 of the treadmill 100 and the position calibration marks 12 and 14. When the shooting direction of the stride video camera 16 is set at a predetermined angle other than a right angle with respect to the arrow A direction, the coordinate conversion process may be performed based on the predetermined angle.
[0017]
The computer 18 computes the image taken by the stride video camera 16 in field units (60 frames per second), and calculates the stride of the subject S. The display unit 20 is configured to include a display device such as an LCD or a CRT, and displays an arithmetic processing result by the computer 18 and the like.
[0018]
The configuration of the computer 18 will be described. As shown in FIG. 3, the computer 18 includes a forefoot detection unit 22, a forefoot position calculation unit 24, a landing determination unit 26, a rear foot position calculation unit 28, a stride calculation unit 30, various data calculation units 32, and a personal data storage unit 34. And a data comparison unit 36.
[0019]
The forefoot detection unit 22 is based on an image taken by the stride video camera 16 and a toe Tf of a foot (hereinafter referred to as “front foot”) located on the front side of the foot F of the subject S swinging forward alternately left and right. Is detected (see FIG. 2). The coordinates of the toe Tf are detected for each field as coordinates in the image (hereinafter referred to as “image coordinates”). Here, the detection processing of the image coordinates of the toe Tf by the forefoot detection unit 22 will be specifically described with reference to the flowchart of FIG.
[0020]
First, an image in the mth field (hereinafter referred to as “m field”) is acquired, and as shown in FIG. 2, a forefoot detection region D1 is extracted from the image (S402). The forefoot detection area D1 is an area where the forefoot toe Tf is assumed to be present on the belt 110 of the treadmill 100. Subsequent to S402, as shown in FIG. 5A, a predetermined pixel row in the forefoot detection area D1 is scanned in the horizontal direction from the front side of the subject S, and pixels having a luminance value different from that of the belt 110 (that is, the foot F (Pixels corresponding to the image) are searched (S404).
[0021]
Then, it is determined whether or not there is a pixel having a luminance value different from that of the belt 110 (S406). If there is no pixel, the process returns to S404 and the processes up to S406 are similarly performed for other pixel columns. In S404, as shown in FIG. 5 (a), the center pixel row in the forefoot detection area D1 is first scanned, and then the center of the upper and lower areas is scanned as shown in FIG. 5 (b). If the pixel rows are sequentially scanned, pixels having luminance values different from those of the belt 110 can be found efficiently.
[0022]
On the other hand, if there is a pixel having a luminance value different from that of the belt 110 as a result of the determination in S406, the upper and lower pixel rows are further scanned in the image of the foot F as shown in FIG. A front edge E1 that is convex forward is acquired (S408). Then, the image coordinate of the point positioned most forward in the front edge E1 is detected as the image coordinate of the forefoot toe Tf in the m field (S410).
[0023]
Note that the detection processing of the image coordinates of the toe Tf by the forefoot detector 22 is not limited to the above. For example, pixels having a luminance value different from that of the belt 110 in the forefoot detection region D1 are pixel-integrated in the horizontal direction, and a pixel row where the toe Tf exists is estimated based on the profile. Then, the image coordinate of the forefoot toe Tf may be detected by detecting the pixel located in the forefront among the pixels having a luminance value different from that of the belt 110 in the estimated pixel row.
[0024]
The forefoot position calculation unit 24 converts the image coordinates of the toe Tf detected by the forefoot detection unit 22 into coordinates in the real space (hereinafter referred to as “real space coordinates”) based on the position calibration marks 12 and 14, and The position of the toe Tf in the real space (hereinafter referred to as “real space position”) is calculated. Here, the calculation process of the real space position of the toe Tf by the forefoot position calculation unit 24 will be specifically described. In FIG. 6, the X axis is set on the position calibration marks 12a and 12b with the position of the position calibration mark 12a as the origin, and the Y axis is set in the perpendicular direction.
[0025]
First, as shown in FIG. 6, the image coordinates of the point P1 corresponding to the intersection with the traveling surface 102 when a perpendicular is drawn from the toe Tf onto the traveling surface 102 are acquired. For this purpose, the Y coordinate of the point P1 may be acquired (the X coordinate of the point P1 is equal to the X coordinate of the toe tip Tf). Therefore, as shown in FIG. 7, in the sole detection area D <b> 2 (the area where the sole is assumed to exist and here is a rectangular area having the toe Tf as one vertex) extracted with the toe Tf as a reference, The pixel row is sequentially scanned in the Y-axis direction to obtain the sole edge E2, and the mode value of the edge E2 is obtained as the Y coordinate of the point P1.
[0026]
Since the Y coordinate of the point P1 is the Y coordinate of the sole, the accuracy of the Y coordinate of the point P1 decreases when the foot F does not land on the running surface 102. However, in the calculation of the stride, since the landing determination unit 26 performs the landing determination and only the data when landing is used, data with low accuracy when not landing may be ignored. it can.
[0027]
After obtaining the image coordinates of the point P1, as shown in FIG. 6, the image coordinates of the point Pc that is the intersection of the straight line passing over the position calibration marks 12a and 14a and the straight line passing through the position calibration marks 12b and 14b are calculated. Then, the image coordinates of the point P2, which is the intersection of the straight line passing through the points Pc and P1 and the X axis, are calculated. Then, based on the ratio of the distance in the real space from the position calibration mark 12a to the position calibration mark 12b and the distance in the image, the X coordinate of the point P2 is converted from the image coordinate to the real space coordinate, and the forefoot toe Tf The real space position is calculated. That is, the real space position of the forefoot toe Tf is the distance from the position calibration mark 12a to the forefoot toe Tf along the direction of arrow A in FIG.
[0028]
The forefoot position calculation unit 24 calculates the real space position of the forefoot toe Tf for each field, and stores the actual space position of the toe Tf for the field for the past 4 seconds from the newly calculated field. This is because when calculating the stride of the nth step, the real space position of the toe Tf one step before, that is, the (n−1) th step is used, and a longer stride time (time required for one step) is 2 seconds. It is assumed that the real space position of the toe Tf is stored for the field for the past 4 seconds which is twice as much as that.
[0029]
In this way, the calculation process of the real space position of the toe Tf by the forefoot position calculation unit 24 is performed based on the image coordinate system set with the position calibration marks 12 and 14 as a reference. The position calibration marks 12 and 14 are provided in parallel to the traveling surface 102 of the treadmill 100 and follow the change in the inclination of the traveling surface 102. Therefore, as shown in FIG. The position calibration marks 12 and 14 are moved relative to the traveling surface 102 even when the inclination of the traveling surface 102 is changed in the treadmill 100 that can change the position of the traveling surface 102 or when the traveling surface 102 moves up and down due to vibration caused by the traveling of the subject S. Maintained in parallel. Therefore, if the image coordinates of the toe Tf are converted into real space coordinates based on the position calibration marks 12 and 14, highly accurate coordinate conversion is possible.
[0030]
When the stride video camera 16 has to be installed near the treadmill 100, there is a possibility that the shooting range is insufficient with a normal lens. In such a case, a sufficient shooting range is secured using a wide-angle lens, distortion aberration correction is performed on the acquired image coordinates of the toe Tf, and then coordinate conversion to real space coordinates is performed. .
[0031]
The landing determination unit 26 determines for each field whether or not the forefoot of the subject S has landed on the running surface 102. For example, when the landing determination is performed for the m field, the image coordinates of the toe Tf acquired in the m field are compared with the image coordinates of the toe Tf acquired in the m-1 field and the m-2 field, respectively. Then, when the X coordinate of the toe Tf monotonously increases and the Y coordinate of the toe Tf is constant, it is determined that the forefoot of the subject S in the m field has landed on the running surface 102. The actual space position of the toe Tf in the m field determined by the landing determination unit 26 is set as the landing position of the forefoot in the m field.
[0032]
Thus, the landing on the running surface 102 of the forefoot of the subject S can be obtained based on the time change of the image coordinates of the toe Tf without using a sensor or the like for detecting the landing of the foot on the running surface 102. Can be detected. Note that it is also possible to determine whether or not the forefoot of the subject S has landed on the running surface 102 based only on the condition that the X coordinate of the toe Tf monotonously increases. However, when the driving speed of the belt 110 of the treadmill 100 is extremely low, it is desirable to make a determination by adding a condition that the Y coordinate of the toe tip Tf is constant.
[0033]
The hind foot position calculation unit 28, based on the temporal change in the front foot landing position in each field for the n-1th step, the foot located on the rear side with respect to the landing position of the forefoot for the nth step (hereinafter referred to as "hind foot"). ) Is calculated. The n-th hind leg is the n-1 th hind leg, and the n-th hind leg landing position is whether the hind leg actually lands when the n-th hind leg is landing. It has nothing to do with it. FIG. 9 shows a time change graph of the real space position of the toe Tf. Here, since the driving speed of the belt 110 of the treadmill 100 is constant, the time difference R of the landing position of the front foot of the (n−1) th step is linearly approximated by the minimum error square method, thereby the front foot of the nth step. The landing position Lb of the hind legs at the time of landing on the running surface 102 is calculated. Then, the elapsed time from the start of measurement at the time when the nth step has landed, the front foot landing position Lf, and the rear foot landing position Lb are stored.
[0034]
The stride calculation unit 30 calculates the stride of the nth step by calculating the difference between the landing position Lf of the front foot and the landing position Lb of the hind foot when the nth step stored by the hind leg position calculation unit 28 has landed. calculate. Then, the data indicating the elapsed time at the time when the nth step has landed and the step length of the nth step are stored in the personal data storage unit 34 in association with the subject S, and displayed on the display unit 20 as necessary.
[0035]
The various data calculation unit 32 calculates the stride time of the nth step by calculating the difference between the elapsed time at the time when the nth step has landed and the elapsed time at the time when the n−1th step has landed, or unit time Is divided by the stride time to calculate the number of pitches per unit time. Then, the calculated various data are stored in the personal data storage unit 34 in association with the subject S and displayed on the display unit 20 as necessary.
[0036]
The personal data storage unit 37 stores and stores various data calculated by the stride calculation unit 30 and the various data calculation unit 32 for each individual. In addition, the data comparison unit 36 reads out the past data of the subject S himself / herself, other person's data, standard data, etc. from the personal data storage unit 37 and compares the result with the data of the subject S who is currently measuring the comparison result. It is displayed on the display unit 20.
[0037]
Next, the processing procedure of the stride measuring apparatus 10 will be described according to the flowchart of FIG.
[0038]
When the stride video camera 16 starts capturing an image including the foot F and the position calibration marks 12 and 14 of the subject S traveling on the traveling surface 102 of the treadmill 100, the computer 18 captures the captured image in units of fields. (S1002). In the computer 18, the forefoot detection unit 22 detects the image coordinates of the toe Tf of the forefoot of the subject S based on the acquired image, for example, the image in the m field (S1004). Subsequently, the forefoot position calculation unit 24 converts the image coordinates of the toe Tf detected by the forefoot detection unit 22 into real space coordinates based on the position calibration marks 12 and 14, and calculates the real space position of the toe Tf. (S1006).
[0039]
Then, the landing determination unit 26 determines whether or not the forefoot of the subject S in the m field has landed on the running surface 102 (S1008), and if it determines that it has landed, the landing is confirmed. After that (S1009), the process returns to S1002, and the processes up to S1008 are similarly performed for the m + 1 field. On the other hand, if it is determined in S1008 that it has not landed, it is determined whether or not the forefoot of the subject S has landed on the running surface 102 in the previous time, that is, the m-1 field (S1010). As a result, if the vehicle has not landed, the process returns to S1002 and the processes up to S1010 are similarly performed for the m + 1 field.
[0040]
Until it is determined that the vehicle has landed in this determination of S1010, the processing from S1002 to S1010 is repeated for each field, thereby obtaining the landing position of the forefoot in each field for the n-1 step and the n step. Is done. Then, the hind leg position calculation unit 28 lands the hind legs at the time when the n th step front leg has landed on the running surface 102 based on the temporal change of the front leg landing position in each field for the (n−1) th step. The position is calculated (S1012). Subsequently, the stride calculation unit 30 takes the difference between the landing position of the forefoot and the landing position of the hind foot at the time when the nth step calculated by the hindfoot position calculation unit 28 has landed, so that the step length of the nth step is calculated. Is calculated (S1014). Furthermore, the various data calculation unit 32 calculates the stride time of the nth step by taking the difference between the elapsed time at the time when the nth step has landed and the elapsed time at the time when the n−1th step has landed, The number of pitches per unit time is calculated by dividing the unit time by the stride time (S1016).
[0041]
Then, the display unit 20 displays various data calculated by the stride calculation unit 30 and the various data calculation unit 32 on the display (S1018). FIG. 11 shows a display example on the display by the display unit 20. This display example is data when the driving speed of the belt 110 of the treadmill 100 is gradually accelerated from 4 km / h to 17 km / h and then gradually decelerated again to 4 km / h. In the upper graph, the horizontal axis is the stride length and the vertical axis is the stride time. When the driving speed is slow, the data is plotted in the upper left area of the graph, and as it accelerates, it is plotted in the lower right area of the graph. Is shown moving. The lower graph shows the stride at each step count. Each numerical value in the upper right of the display indicates various data in a predetermined plot of the upper graph. Based on the upper and lower graphs, it is possible to accurately grasp how the stride and stride time of the subject S change according to the driving speed of the belt 110.
[0042]
As described above, according to the stride measuring device 10, an image including the foot F of the subject S is taken, and on the basis of this image, the n-1th step that has landed sequentially on the running surface 102 of the treadmill 100 and The landing position of the forefoot in each field for the nth step is acquired, and the landing position of the hindfoot with respect to the landing position of the forefoot in the nth step based on the time change of the landing position of the forefoot in each field for the (n−1) th step By calculating the position, the relative distance between the landing position of the front foot and the landing position of the rear foot can be calculated as the stride. Accordingly, it is possible to measure the stride with high accuracy with a simple configuration without using the measurement of the driving speed of the belt 110 of the treadmill 100 or the sensor for detecting the landing of the foot F on the running surface 102. .
[0043]
Moreover, according to the stride measuring device 10, since the step length, stride time, pitch number, running speed, etc. of the subject S can be calculated for each step number, the balance variation of the subject S, the variation of the pace distribution, etc. are grasped. It can be used to improve the competitiveness of the subject S. In addition, the past data of the subject S himself / herself, other people's data, standard data, and the like can be compared with the data of the subject S currently being measured, and the comparison result can be displayed on the display of the display unit 20. The subject S can perform the training while confirming the comparison result, and can correct the own stride etc. on the spot. For the subject S during training, comparison data such as the number of pitches may be notified by sound or light.
[0044]
Further, if a treadmill 100 is provided with a sensor for detecting a mark attached to the subject S and the vertical movement accompanying the traveling of the subject S is measured in real time, the foot F of the subject S is placed on the traveling surface 102 based on this time waveform. The landing time and the time away from the traveling surface 102 can be estimated, whereby the stride time, the hover time, the landing time, and the like can be calculated.
[0045]
As shown in FIG. 1, a posture video camera (posture photographing means) 38 is installed, and the traveling posture of the subject S is photographed from the front, side, back, etc., and the photographed images are simultaneously displayed on the display of the display unit 20. It may be displayed. As a result, the walking posture of the subject can be confirmed and evaluated simultaneously with the stride, and the walking posture can be efficiently modified.
[0046]
As mentioned above, although preferred embodiment of this invention was described in detail, this invention is not limited to the said embodiment. For example, in the above embodiment, the calculation process of the real space position of the toe Tf by the forefoot position calculation unit 24 is performed based on the image coordinate system set with the position calibration marks 12 and 14 as a reference. However, even if the position calibration marks 12 and 14 are not used, the real space position of the toe Tf is calculated from the image coordinates of the toe Tf if conditions such as the shooting distance and the shooting magnification by the stride video camera 16 are stored in advance. can do.
[0047]
【The invention's effect】
As described above, the stride measuring device according to the present invention is a stride measuring device that measures the stride of a subject who travels or walks on the running surface of a belt driven at a predetermined speed, and includes the feet of the subject. An image capturing means for capturing an image and the position of one foot landed on the running surface are obtained based on the image, and the position of the other foot landed on the running surface following the one foot is obtained based on the image. Then, the position of one foot with respect to the position of the other foot is calculated based on the time change of the position of one foot, and the relative distance between the position of the other foot and the calculated position of the one foot is calculated as a stride. By including the stride calculation means, it is possible to measure the stride with high accuracy while having a simple configuration.
[Brief description of the drawings]
FIG. 1 is a diagram showing an embodiment of a stride measuring apparatus according to the present invention.
FIG. 2 is a diagram showing an image taken by a stride video camera of the stride measuring apparatus shown in FIG. 1;
FIG. 3 is a block diagram showing a functional configuration of a computer of the stride measuring apparatus shown in FIG. 1;
4 is a flowchart for explaining detection processing of image coordinates of a toe by a forefoot detecting unit of the stride measuring apparatus shown in FIG. 1. FIG.
5 is a diagram for explaining detection processing of image coordinates of a toe by a forefoot detection unit of the stride measuring apparatus shown in FIG. 1, and (a) scans a predetermined pixel row in a horizontal direction in the forefoot detection region; (B) is a conceptual diagram showing a case where another pixel row is scanned in the horizontal direction following (a) in the forefoot detection region, and (c) is a convex forward image in the foot image. It is a conceptual diagram which shows the case where the front edge which has become is acquired.
6 is a diagram for explaining processing for calculating a real space position of a toe by a forefoot position calculating unit of the stride measuring apparatus shown in FIG. 1; FIG.
7 is a diagram for explaining processing for acquiring a foot edge by a forefoot position calculating unit of the stride measuring apparatus shown in FIG. 1; FIG.
8 is a diagram for explaining an image coordinate system setting process based on a position calibration mark by a forefoot position calculation unit of the stride measuring apparatus shown in FIG. 1; FIG.
9 is a diagram for explaining a calculation process of a landing position of a hind leg by a hind leg position calculating unit of the stride measuring apparatus shown in FIG. 1. FIG.
10 is a flowchart for explaining a processing procedure of the stride measuring apparatus shown in FIG. 1. FIG.
11 is a diagram showing a display example on the display by the display unit of the stride measuring apparatus shown in FIG. 1. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Stride measuring apparatus 12, 12a, 12b, 14, 14a, 14b ... Position calibration mark, 16 ... Stride video camera (photographing means), 18 ... Computer (step length calculating means), 20 ... Display part, 22 ... Forefoot Detection unit, 24 ... forefoot position calculation unit, 26 ... landing determination unit, 28 ... hind foot position calculation unit, 30 ... stride length calculation unit, 38 ... posture video camera (posture photographing means), S ... subject, F ... foot, Tf: forefoot toe, Lf: landing position of the front foot, Lb: landing position of the rear foot.

Claims (7)

A stride measuring device for measuring a stride of a subject who runs or walks on a running surface of a belt driven at a predetermined speed,
Photographing means for photographing an image including the subject's feet;
Acquiring the position of one foot landed on the running surface based on the image, obtaining the position of the other foot landed on the running surface following the one foot, based on the image, and The position of the one foot relative to the position of the other foot is calculated based on the temporal change in the position of the one foot, and the relative distance between the position of the other foot and the calculated position of the one foot is used as a stride. A stride measuring device comprising stride calculating means for calculating. The stride calculation means acquires a position of a predetermined portion of the subject's foot based on the image, and whether or not the subject's foot has landed on the running surface based on a time change of the position of the predetermined portion. The stride measuring device according to claim 1, wherein the stride measuring device is determined. A position calibration mark provided at a predetermined angle with respect to the traveling surface and following a change in the inclination of the traveling surface;
The stride measuring device according to claim 1 or 2, wherein the stride calculation means performs coordinate conversion of coordinates in the image to coordinates in real space based on the position calibration mark. The stride measuring device according to any one of claims 1 to 3, further comprising posture photographing means for photographing the running posture or the walking posture of the subject from at least one direction of the front or side of the subject. A stride measurement method for measuring a stride of a subject running or walking on a running surface of a belt driven at a predetermined speed,
A photographing step of photographing an image including the subject's feet;
Acquiring the position of one foot landed on the running surface based on the image, obtaining the position of the other foot landed on the running surface following the one foot, based on the image, and The position of the one foot relative to the position of the other foot is calculated based on the temporal change in the position of the one foot, and the relative distance between the position of the other foot and the calculated position of the one foot is used as a stride. A step length measuring method comprising: a step length calculating step. In the step calculation step, the position of the predetermined part of the subject's foot is acquired based on the image, and the subject's foot is landed on the running surface based on the time change of the position of the predetermined part 6. The stride measuring method according to claim 5, wherein it is determined whether or not. In the step calculation step, the coordinates in the image are converted into coordinates in the real space based on a position calibration mark that is provided at a predetermined angle with respect to the traveling surface and follows a change in the inclination of the traveling surface. The step length measuring method according to claim 5 or 6.

Images