Foot evaluation system and method

Abstract

To solve a problem in which the presence or absence of abnormality from a sole to an upper region of a heel of a human cannot be determined.SOLUTION: This foot part measurement device 100 comprises a box-shaped main body 1 where an upper plate 2 is constituted of a transparent acrylic plate. For example, the upper plate 2 is a square of one side of 70 cm, and multiple markers 3 for positioning are provided on the surface. A complicated design such as paisley is displayed on the surface. The markers 3 each are provided in different colors or shapes by a total of 2-pieces each in the center of both feet malleolus medialis and in the center of both feet first caput ossis metatarsalis, a total of 4-pieces each at four corners or a total of 8-pieces including a midpoint. The upper plate 2 is transparent, and therefore a foot part, particularly a sole, can be measured from a lower side of the upper plate 2. Cameras 5 are provided in six places of the upper plate 2. The cameras 5 are provided by 1-piece each in the middle position of the sides of the longitudinal direction (before and after a user gets on), and 2-pieces each in the position of longitudinal 1 / 3 of the lateral sides.SELECTED DRAWING: Figure 1

Description

Technical Field

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[0001] The present invention relates to a technique for determining the presence or absence of abnormalities in the area from the sole of a human foot to above the heel.

Background Art

[0002] There are various types in the area from the sole of the foot to above the heel, for example, up to below the knee (hereinafter referred to as "foot part") due to age, environment, and other factors. Here, when there is deformation to such an extent that there is a risk of causing difficulty in walking, such as valgus of the heel, hallux valgus, or deformation of the little toe, that is, when there is an abnormality in the foot part. However, conventionally, there has been no technique for simply and quantitatively determining such an abnormality.

[0003] As another conventional technique, there is a technique for evaluating walking ability using a sheet-type pressure sensor (see Patent Document 1). However, such a conventional technique (Patent Document 1) cannot determine the presence or absence of an abnormality in the area from the sole of a human foot to above the heel.

Prior Art Documents

Patent Documents

[0004] <​​​​​​​​​​​​​​​​​​​The foot evaluation system according to the present invention has a box-shaped body, the top plate of the body is transparent, cameras and other imaging means are fixed at a predetermined height at multiple locations on the top plate, multiple markers are provided at predetermined locations on the surface of the top plate, cameras and other imaging means are also provided inside the body, and a pattern is provided on the surface of the top plate or inside the body that can be seen through the top plate.

[0007] Furthermore, it is preferable to provide a three-dimensional image forming means that forms a three-dimensional image from a plurality of images captured by the aforementioned imaging means. [Brief explanation of the drawing]

[0008] [Figure 1] This is a perspective view showing a foot measurement device according to Embodiment 1 of the present invention. [Figure 2] Figure 1 shows a cross-sectional view of the foot measurement device. [Figure 3] This is an explanatory diagram showing the positions of the markers and camera of the foot measurement device shown in Figure 1. [Figure 4] Figure 1 shows the configuration diagram of the foot measurement device. [Figure 5] This is a diagram of the camera's configuration. [Figure 6] This is a flowchart showing the operation of the foot measurement device. [Figure 7] This is an explanatory diagram showing an example of a captured image. [Figure 8] This is an explanatory diagram showing an example of an image taken from below. [Figure 9] This is a perspective view showing a foot measurement device according to Embodiment 2 of the present invention. [Figure 10] This is a plan view showing a foot measurement device. [Figure 11] This is a cross-sectional view of the rail system. [Figure 12] This is a cross-sectional view of the main body. [Figure 13] This is a flowchart showing the operation of the foot measurement device. [Modes for carrying out the invention]

[0009] (Embodiment 1) Figure 1 is a perspective view showing a foot measurement device according to Embodiment 1 of the present invention. Figure 2 is a cross-sectional view of the foot measurement device shown in Figure 1, and Figure 3 is an explanatory diagram showing the positions of the markers and camera of the foot measurement device shown in Figure 1. Figure 4 is a configuration diagram of the foot measurement device shown in Figure 1. This foot measurement device 100 consists of a box-shaped body 1 whose top plate 2 is made of a transparent acrylic plate. The top plate 2 is, for example, a square with sides of 70 cm, and a plurality of markers 3 for positioning are provided on its surface. Furthermore, a complex pattern such as paisley is displayed on the surface in order to avoid disturbing the characteristic points of the foot.

[0010] Markers 3 are placed in a total of two locations: one at the center of the medial malleolus of both feet and one at the center of the first metatarsal head of both feet, and one at each of the four corners (a total of eight including the midpoint). Each marker is of a different color or shape. Markers 3 may be printed or attached as stickers. A small light source may also be used (not shown in the illustration).

[0011] The aforementioned pattern shall be one that is clearly not present in the surrounding space in order to identify the contour of the foot. For example, a paisley pattern is preferable because it is often not present in typical measurement environments. The pattern shall consist of thin lines and shall not obstruct visibility from below.

[0012] Since the upper plate 2 is transparent, the foot, especially the sole of the foot, can be measured from the underside of the upper plate 2. Furthermore, because the upper plate 2 is transparent, the pattern may be placed on the inner surface of the main body 1. In this case, since there is no pattern on the upper plate 2, the sole of the foot can be photographed clearly, improving the accuracy of the three-dimensional modeling of the foot.

[0013] As shown in Figure 3, an explanatory diagram illustrating the positional relationship, markers 3 for aligning the floor surface inside the main body 1 are also provided. Two of these markers 3 are provided, one at the center of the medial malleolus of both feet and one at the center of the first metatarsal head of both feet.

[0014] Six cameras 5 are provided at six locations on the upper plate 2. One camera 5 is provided at the center position of each side in the front-rear direction (front and rear when the user is on board), and two cameras 5 are provided at the positions 1 / 3 in the front and rear of each side in the lateral direction. In other words, the cameras 5 are installed at positions every 60 degrees with the heel at 0 degrees. As shown in Fig. 5(a), each camera 5 is supported by a support column 31. The support column is fixed to the upper plate 2 with a coil spring at its base. It is sufficient to be able to photograph 15 cm (20 cm) above the floor. Also, as shown in Fig. 5(b), one camera 5 supported by a flexible arm 32 is provided above the upper plate 2 (two may be provided, not shown).

[0015] Inside the main body 1 and at the central position in plan view, one upward-facing camera 5 is provided. A light source 6 is provided around the camera 5. The light source 6 may be the tip of an optical fiber that introduces LED or sunlight from the outside (not shown).

[0016] As shown in Fig. 4, the foot measurement device 100 includes an image acquisition unit 11 that acquires image information from the camera 5, a foot shape generation unit 12 that generates the shape of the foot in three dimensions from the acquired image, a pressure distribution acquisition unit 13 that acquires the pressure distribution from the contact state of the sole of the foot on the upper plate 2 in the acquired image, an evaluation unit 14 that evaluates the state of the foot from the shape and pressure distribution of the foot, etc., and a display unit 15.

[0017] Fig. 6 is a flowchart showing the operation of the foot measurement device100. First, measurement preparation is performed (step S1). The user places both feet on the graphic part of the footrest position on the upper plate 2. In this state, the camera 5 is positioned above the foot using the flexible arm. Further, the light source 6 inside the main body 1 is turned on to irradiate the sole of the foot with light.

[0018] The image acquisition unit 11 acquires image information from the camera 5 (step S2). The foot shape generation unit 12 calculates and acquires the position and size of the foot based on the marker 3 that is visible in the captured image. Figure 7 shows examples of captured images. Figure (a) shows an image taken from the front. Figure (b) shows an image taken from the rear. Figure (c) shows an image taken from the right rear. An image taken from the left rear is similar (not shown). Figure (d) shows an image taken from the right front. An image taken from the left front is similar (not shown). Figure 8 shows an image taken from below.

[0019] The foot shape generation unit 12 generates a three-dimensional shape of the foot from this information (step S3). Known techniques such as the SfM method are used to generate the three-dimensional shape. Since distance is corrected using the marker 3, the dimensions, angles, etc., of the foot's feature points can be automatically measured. Furthermore, by using an image of the sole of the foot in conjunction, the entire foot can be rendered in three dimensions.

[0020] Next, the pressure distribution acquisition unit 13 acquires an image showing the portion of the sole of the foot in contact with the upper surface, and obtains the pressure distribution of the sole of the foot from the shape and density of this contact portion (step S4). In addition, the center of gravity is obtained from the pressure distribution of both feet.

[0021] Next, the foot is evaluated based on the three-dimensional image and pressure distribution created above (Step S5). Evaluating the foot reveals the following: a. It reveals the skeletal structure in both sitting and standing positions (such as heel curvature, bunion angle, and foot thickness). b. Comparing the changes between standing and sitting positions reveals the degree of flexibility of the musculoskeletal system of the foot (excessive flexibility increases the risk of foot deformities). c. Understanding balance function (focusing on the transition from sitting to standing, which is attracting attention in the field of locomotive syndrome) Specifically, the upper part of the device allows for the examination of the instability of both feet, including the navicular bone and lateral malleolus, while the lower part of the device allows for the examination of the contact area of ​​the sole of the foot and changes in the heel, forefoot, and toes. d. The shape and length of the toenails can be measured using the toe-side camera 5 and the upper camera 5. Specifically, the stress on the toenails can be estimated using the contact condition of the toes from the underfloor camera 5.

[0022] Furthermore, by continuously capturing the movement from sitting to standing, changes in the skeletal model of the foot and sole can be obtained. Since multiple cameras 5 are fixed in place, continuous shooting from all angles is possible. The standing movement is captured by all of the cameras 5 in time units (e.g., in 0.1-second units), and the three-dimensional shape of the foot is generated in time units in the above step. This allows for the acquisition of changes in the skeletal model of the foot and sole, enabling a more detailed evaluation of the foot.

[0023] According to the foot measurement device 100 of the present invention, the image quality of still images is improved because the camera position is fixed. Furthermore, because the camera position is fixed, it becomes possible to capture human movement.

[0024] (Embodiment 2) Figure 9 is a perspective view showing a foot measurement device according to Embodiment 2 of the present invention. Figure 10 is a plan view showing the foot measurement device. This foot measurement device 200 is characterized in that it uses a camera 205 mounted on a portable information terminal S instead of the camera 5 of Embodiment 1. This foot measurement device 200 consists of a box-shaped body 201 whose top plate 202 is made of a transparent acrylic plate. The top plate 202 is, for example, a square with sides of 70 cm, and a plurality of positioning markers 203 are provided on its surface. Furthermore, a complex pattern such as paisley is displayed on the surface in order to avoid disturbing the characteristic points of the foot.

[0025] Markers 203 are provided in a total of two locations: one at the center of the medial malleolus of both feet and one at the center of the first metatarsal head of both feet, and one at each of the four corners (a total of eight including the midpoint), each in a different color or shape. Markers 203 may be printed or attached as stickers. A small light source may also be used (not shown in the illustration). The pattern should be one that is clearly not present in the surrounding space in order to identify the contour of the foot. For example, a paisley pattern is preferred because it is often not present in typical measurement environments. The pattern should consist of fine lines and should not obstruct visibility from below.

[0026] Since the upper plate 202 is transparent, the foot, especially the sole of the foot, can be measured from the underside of the upper plate 202. Furthermore, because the upper plate 202 is transparent, the pattern may be provided on the inner surface of the main body 201. In this case, since there is no pattern on the upper plate 202, the sole of the foot can be photographed clearly, improving the accuracy of three-dimensional modeling of the foot. Markers 203 for aligning the above and below the floor are also provided on the floor surface inside the main body 201. Two markers 203 are provided, one at the center of the medial malleolus of both feet and one at the center of the first metatarsal head of both feet.

[0027] A ring-shaped rail device 250 is arranged around the main body 201. This rail device 250 has a two-part structure, upper and lower. As shown in the cross-sectional view in Figure 11(a), the lower ring 251 has a groove 252 around its upper end, and multiple gears 253 are provided within the groove 252. As shown in Figure 11(b), one gear 253 is connected to a motor 255 via a gearbox 254. The motor 255 is rotated by a control device 256. Gears are also evenly spaced at multiple locations. The upper ring 257 has teeth 258 at its lower end that mesh with the gears 253. The upper ring 257 is also supported by the gears 253. When the gears 253 rotate, the upper ring 257 rotates. The upper ring 257 is also provided with a holder 258 for holding a portable information terminal S.

[0028] The motor 255 is connected to a control device 256. The control device 256 is configured to be connectable to a mobile information terminal S via a USB cable or the like, and controls the motor to rotate at a predetermined rotational speed using an application program installed on the mobile information terminal S.

[0029] As shown in Figure 12, the top plate 202 of the main body 201 is provided with an opening 21. The cover 22 of the opening 21 opens outward, and its inner surface becomes a mirror. Multiple mirrors 23 are provided inside the main body 1, allowing the soles of the feet to be seen from below the top plate 2. When the opening 21 is open, it is at approximately the same height as the camera 205 of the portable information terminal S held on the rail device 250.

[0030] Furthermore, the foot measurement device 200 includes an image acquisition unit that acquires image information from the camera 205 of the portable information terminal S, a foot shape generation unit that generates the shape of the foot in three dimensions from the acquired image, a pressure distribution acquisition unit that acquires the pressure distribution from the contact state of the sole of the foot with the upper plate 202, and an evaluation unit that evaluates the condition of the foot from the shape of the foot, pressure distribution, etc. These are composed of an application program installed on the portable information terminal S and a separate computer system connected to the portable information terminal's hardware or network.

[0031] Figure 13 is a flowchart showing the operation of this foot sole measurement device. First, preparations for measurement are made (step S1). The user places both feet on the foot placement area marked with a figure on the upper plate 202. In this state, the portable information terminal is rotated by the rail device 250 to take continuous images of the foot from all angles. The shooting angle can be freely set. For example, images can be taken every 60 degrees, or every 1 degree. Furthermore, the light inside the main unit 201 is turned on to illuminate the soles of the feet.

[0032] The image acquisition unit acquires image information from the camera 205 (step S2). If there are many acquired images, it selects and uses an image taken from an angle suitable for generating a three-dimensional shape. The foot shape generation unit calculates and acquires the position and size of the foot based on the marker 203 that is reflected in the acquired image.

[0033] The foot shape generation unit generates a three-dimensional shape of the foot from this information (step S3). Known techniques such as the SfM method are used to generate the three-dimensional shape. Since distance is corrected using marker 203, the dimensions, angles, etc., of the foot's feature points can be automatically measured. Furthermore, by using an image of the sole of the foot in conjunction, the entire foot can be represented in three dimensions.

[0034] Next, the pressure distribution acquisition unit acquires an image of the portion of the sole of the foot that is in contact with the upper surface, and obtains the pressure distribution of the sole of the foot from the shape and density of this contact portion (step S4). In addition, the center of gravity is obtained from the pressure distribution of both feet. The sole of the foot is photographed by opening the lid and using a mirror on the inner surface of the lid and a mirror placed inside the main body 201 to photograph the sole of the foot. With the lid open, the inner surface faces the portable information terminal.

[0035] Next, the foot is evaluated based on the three-dimensional image and pressure distribution created above (Step S5). Evaluating the foot reveals the following: a. It reveals the skeletal structure in both sitting and standing positions (such as heel curvature, bunion angle, and foot thickness). b. Comparing the changes between standing and sitting positions reveals the degree of flexibility of the musculoskeletal system of the foot (excessive flexibility increases the risk of foot deformities). c. Understanding balance function (focusing on the transition from sitting to standing, which is attracting attention in the field of locomotive syndrome) Specifically, the upper part of the device allows for the examination of the instability of both feet, including the navicular bone and lateral malleolus, while the lower part of the device allows for the examination of the contact area of ​​the sole of the foot and changes in the heel, forefoot, and toes. d. The shape and length of the toenails can be measured using the toe-side camera 5 and the upper camera 5. Specifically, the stress on the toenails can be estimated using the contact condition of the toes from the underfloor camera 5.

[0036] According to the foot measurement device 200 of the present invention, since images are taken using the camera 205 of the portable information terminal S and data processing is performed on the portable information terminal S or a computer system connected thereto, the device configuration only requires the main body 201 and the rail device 250. Therefore, the device configuration can be simplified.

[0037] (Other embodiments) By applying some kind of processing between the acrylic plates that make up the upper plate 2, an indicator of pressure can be estimated. For example, if oil is placed between the two acrylic plates, a striped pattern will appear when pressure is applied. Photographing this pattern can provide an indicator of pressure. [Explanation of symbols]

[0038] 100 Foot Measurement Device 1 Main unit 2 Top board 3 Markers 4 patterns 5 Cameras 6 light source 11 Image acquisition unit 12 Foot shape generation section 13 Pressure distribution acquisition unit 14. Evaluation Department

Claims

1. The main body has a transparent box-shaped upper plate on which the foot rests, and the surface of the upper plate has markers provided at least in the center of both medial malleoli, in the center of each first metatarsal head, and in each of the four corners, and a pattern is provided on the surface of the upper plate or on the inner surface visible through the upper plate. At a minimum, a mirror positioned inside the main body that changes the shooting direction of a portable information terminal or other shooting means having a shooting function located on the upper part of the upper plate so that it faces the soles of the feet, and a lid of an opening provided in the upper plate that opens outward and has a mirror on its inner side as a reflective surface, A three-dimensional image forming means for forming a three-dimensional image from a plurality of images including the marker captured by the aforementioned photographing means, A foot evaluation system characterized by having the following features.

2. The main body has a transparent box-shaped upper plate on which the foot rests, and the surface of the upper plate has markers provided at least in the center of both medial malleoli, in the center of each first metatarsal head, and in each of the four corners, and a pattern is provided on the surface of the upper plate or on the inner surface visible through the upper plate. At a minimum, a mirror positioned inside the main body that changes the shooting direction of a portable information terminal or other shooting means having a shooting function so that it is directed toward the soles of the feet, and a lid for an opening provided in the upper plate that opens outward and has a mirror on its inner side as a reflective surface, A device for moving a shooting means is arranged around the main body, with a holding portion for the shooting means provided at its upper part, and the holding portion moves along the circumference of the main body. A three-dimensional image forming means that forms a three-dimensional image from a plurality of images including the marker, which are captured by the imaging means located on the upper part of the upper plate, by being held by the holding part, A foot evaluation system characterized by having the following features.

Images