TWI728591B - Device and method for analyzing the arch of the foot - Google Patents

Abstract

A method for analyzing the arch of the foot comprises a preparation step for preparing required instruments, a pre-control step for creating a pre-control information by scanning a non-stepped pad with a scanning unit, a stepping step for creating a pre-comparison information showing the deformation of the stepped pad, an image processing step for respectively processing the pre-control information and the pre-comparison information into the control information and the comparison information, a comparison step for comparing the difference between the control information and the comparison information, and a determining step for determining the type of the arch of the foot. By operating the comparison step to compare the pixel difference between the control information and the comparison information that respectively showing the deformation before and after the pad is stepped on, so as to determine the type of the arch of the foot.

Description

Foot arch measurement method and device

The present invention relates to a measuring method, in particular to a method and device for measuring the arch of the foot.

Foot health is closely related to humans. No matter walking, running, jumping, or exercising, the feet are under considerable pressure every day. Therefore, choosing suitable shoes or insoles for different types of activities has become a major issue, and everyone’s soles The size, length and width, and arch shape of the foot are all very different. From the size and size, the last to the high and low arches, they will all affect the comfort of consumers when wearing them.

According to the survey, 70% of Taiwanese have normal arches, 10% have high arches, and 20% have low arches. In other words, 30% of the population have high or low arches. In view of the fact that high arches and low arches may affect sports performance, walking gait, and even health, the trend of testing one's arches and purchasing corresponding shoes has gradually become popular.

One of the current methods for detecting the shape of the arch of the foot is performed by X-ray irradiation. After taking off the stockings, the subject stands on a platform and receives X-ray irradiation from the side. After the arch angle shown in the photo, the shape of the arch of the subject can be confirmed. However, the X-ray irradiation method needs to be carried out in a hospital or a specialist clinic, which means that consumers also need to go to the hospital to confirm the shape of their arches before they can purchase shoes according to their needs, which is quite inconvenient.

Therefore, the purpose of the present invention is to provide a method and device for measuring the arch of the foot that improve the convenience of detection.

Therefore, the foot arch measurement method of the present invention includes a preparation step of preparing the required equipment, a pre-comparison step of generating a pre-comparison information, a pedaling step of generating a pre-comparison information, a pre-comparison information and the pre-comparison step. The pre-comparison information is separately processed into the image processing steps of the control information and the comparison information, a comparison step of comparing the comparison information and the difference of the comparison information, and a judgment of the arch type of the subject step.

The preparation step is to prepare a treading mat suitable for a test subject to step on and showing a pressure condition, a measurement platform for carrying the treading mat, and a measuring platform suitable for scanning the pressure condition of the treading mat to produce at least An optical image detection unit.

The pre-checking step is to scan the pedaling pad by the detection unit to generate the pre-checking information showing the type of the pedaling pad that has not been stepped on.

The stepping step is to enable the detection unit to scan the deformation of the stepping pad when the subject stepped on the stepping pad, and generate the pre-comparison information.

The image processing step uses an image processing unit to convert the pre-comparison information and the pre-comparison information into the control information and the comparison information, respectively, and includes a A gray-scale conversion process for gray-scale conversion, and a normalized process for adjusting hue, saturation, and lightness.

The difference comparison step is to compare the comparison information and the comparison information, and generate a result display information having a plurality of color gradation differences between the comparison information and the comparison information.

Finally, the interpretation step is to analyze the result display information and determine the foot arch shape of the subject, and includes a foot pressure distribution calculation process that distinguishes at least the difference between the result display information Two analysis areas, and the sum of the differences of each analysis area is divided by the total number of differences of each analysis area to form a difference concentration value, and the corresponding difference concentration value of the at least two analysis areas is compared.

Another object of the present invention is to provide an arch measurement device suitable for performing the arch measurement method described above. The arch measurement device includes an arch measurement device suitable for being stepped on by the subject and showing pressure on the bottom surface. A stepping mat under conditions, a measuring platform for supporting the stepping mat, a detection unit suitable for scanning the pressure condition of the stepping mat to produce at least one optical image, and an image suitable for processing the at least one optical image Processing unit.

Wherein, the material of the treading pad is a combination of polyurethane and non-woven fabric; and the image processing unit includes a gray-scale conversion element for gray-scale conversion, a difference comparison element for difference comparison, and a screen out. De-noise files that need information.

The effect of the present invention is that the detection unit scans the deformation of the pedaling mat made of special material after being stepped on, and uses the difference comparison method to make the deformation difference Convert it into a color gradation difference, and compare the color gradation difference before and after the subject is stepped on to analyze the deformation of the pedaling pad caused by the pressure of the subject’s foot, and finally analyze the subject through the interpretation step The arch shape of the foot can be analyzed without X-rays.

L: horizontal line

A: Reference point

B: reference point

C: reference point

A1: Analysis area

A2: Analysis area

A3: Analysis area

B1: Analysis area

B2: Analysis area

B3: Analysis area

1: Preparation steps

2: Pre-control step

3: stepping on steps

4: Image processing steps

41: Grayscale conversion process

42: regularization process

5: Difference comparison steps

6: finishing steps

61: Reverse process

62: Smoothing the process

63: Edge detection process

64: Conversion process

65: Light and shadow elimination process

66: Decrease resolution process

7: Interpretation steps

71: Binarization process

72: Judgment process

73: Foot pressure distribution calculation process

74: Color table conversion process

81: Stepping Pad

82: measurement platform

83: detection unit

Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, in which: FIG. 1 is a block flow chart illustrating one method embodiment of the foot arch measurement method of the present invention; FIG. 2 is a Schematic diagram illustrating an embodiment of the foot arch measurement device of the present invention; Figure 3 is an optical image diagram illustrating a pre-comparison information; Figure 4 is an optical image diagram illustrating a pre-comparison information; Figure 5 is a gray Figure 6 is a gray-scale image diagram illustrating a comparison information; Figure 7 is an image analysis diagram illustrating a result display information; Figure 8 is an image analysis diagram illustrating one of them The arch shape of the subject; Figure 9 is an image analysis diagram illustrating the arch shape of another subject; Figure 10 is an image analysis diagram illustrating the foot pressure distribution pattern of one of the subjects And Figure 11 is an image analysis diagram illustrating the foot pressure distribution pattern of another subject.

1 and 2, an embodiment of the foot arch measurement method of the present invention includes a preparation step of preparing the required equipment 1, a pre-comparison step of generating a pre-comparison information, and a pre-comparison step of generating a pre-comparison information Step 3, an image processing step of processing the pre-comparison information and the pre-comparison information into comparison information and comparison information, respectively, a comparison of the difference between the comparison information and the comparison information, step 5 , A trimming step 6 for further adjustment of the image, and a judgment step 7 for judging the shape of the arch of the subject.

The preparation step 1 is to prepare a treading pad 81 suitable for being stepped on by a subject and presenting a stressed condition on the bottom surface, a measuring platform 82 for supporting the treading pad 81, and a treading pad 81 suitable for scanning the treading pad 81 A detection unit 83 that generates at least one optical image under pressure.

Among them, the measurement platform 82 is a transparent reinforced flat plate, and because it needs to be directly stepped on when in use, it is preferably a high-strength glass that can bear the weight of the human body; the image processing unit is specifically an image processing algorithm that can be executed The processing equipment includes a gray-scale conversion component for gray-scale conversion, a difference comparison component for pixel point difference comparison, and a denoising component that screens out the required information. In addition, the detection unit 83 is an optical image scanner capable of scanning and generating optical images, and the material of the stepping pad 81 is a combination of polyurethane and non-woven fabric. Experiments have confirmed that this material has good resilience and deformation under pressure. Ability, so whether the subject takes off his socks or not, he can accurately The bottom surface of the pedal 81 shows the pressure condition, and after the measurement is completed, it can rebound and return to its original state for the next subject to test.

3, the pre-comparison step 2 uses the detection unit 83 to scan the pedaling pad 81 to generate the pre-comparison information showing the type of the pedaling pad 81 that has not been stepped on, and the pre-comparison information will show that the current detection The original state of the stepping mat 81 was set as a control group.

Referring to FIG. 4, the stepping step 3 is to make the detection unit 83 scan the condition that the subject stepped on the stepping pad 81 and the stepping pad 81 is deformed, and generate information that will be compared with the pre-comparison in shape, light and shadow. The pre-comparison information that has a gap.

Referring to Figures 5 and 6, the image processing step 4 uses an image processing unit to convert the pre-comparison information and the pre-comparison information into the control information and the comparison information, and includes a pre-comparison information and The pre-comparison information respectively performs a gray-scale conversion process 41 of gray-scale conversion, and a normalization process 42 of adjusting hue, saturation, and lightness. In fact, different image processing algorithms convert the pre-comparison information and the pre-comparison information into the comparison information and the comparison information with good saturation and brightness, and only showing a gray-scale pattern with different shades. , In order to facilitate the next steps.

The difference comparison step 5 is to compare the difference between the comparison information and the comparison information, and generate a result display information having a plurality of color gradation differences between the comparison information and the comparison information.

Since the comparison information and the comparison information respectively show that the pedaling pad 81 Before and after the pedaling pattern, the pixels at the same position will be affected by the pressure from the arch of the foot. Therefore, the comparison step 5 can be used to compare the comparison information with the comparison information before and after the pedaling. The gray-scale difference of the pixel points is analyzed to analyze the change of the plantar pressure with respect to the pedaling pad 81. But because the result shows that the information still has a lot of noise at this time, it will cause a lot of errors in analysis. Therefore, it is necessary to perform the trimming step 6 to filter out unnecessary noise. The trimming step 6 includes a color inversion Reverse process 61, a smoothing process 62, an edge detection process 63, a straightening process 64 for turning the sole of the foot upright, a light and shadow elimination process 65 for excluding light and shadow other than the sole of the foot, and a descending resolution process 66. Wherein, the smoothing process 62 is a smoothing algorithm known in the related art that averages adjacent pixels to make the values closer to each other and smooth; and the edge detection process 63 uses a Sauber filter. (Sobel Filter); the resolution reduction process 66 uses the pyramid method to increase the resolution of the image.

Referring to Fig. 7 and in conjunction with Fig. 1, according to the information displayed after the processing of the trimming step 6, the judgment step 7 for judging the arch shape can be performed as follows. The judgment step 7 includes a binarization process 71, and A determination process 72. The binarization process 71 uses the Otsu thresholding algorithm (Otsu thresholding). According to the result, the difference distribution on the information is displayed. Using the exhaustive method, find a way to maximize the variance between classes and the smallest within classes. The threshold for distinguishing the two types of pixels, and then the difference in the result display information is distinguished according to the threshold, and the difference above the threshold is marked as a first contrast color, and the difference is lower than the threshold. The differences of the values are all marked as different from the first contrast color The second contrast color forms a binary image. In this embodiment, the threshold value is 130, the first contrast color is black, and the second contrast color is white. However, it is not limited to this. The user can perform the first The contrast color and the second contrast color are adjusted to make the arch shape of the sole of the foot more clear. Also, because of the difference in the arch shape of each person, the difference distribution of the information displayed by each result is also different. Therefore, through the aforementioned The threshold obtained by the Otsu binarization algorithm will also be different.

Refer to Figure 8 and Figure 9, the result display information will now show the arch shape of the subject’s two soles. The judgment process 72 will be used to determine the high and low arches. First, define a pass through the center of the sole. And define the position where the horizontal line L passes through the inner curve of the sole of the foot as the reference point A, and then define the points where the horizontal line L passes through the inner and outer edges of the sole of the foot as reference points B and C, then Calculate the ratio of the distance from the reference point A to the reference point C to the distance from the reference point B to the reference point C, and judge the height of the arch according to the obtained ratio. In this embodiment, the set ratio between 0.0 and 0.45 is a high arch, a ratio between 0.45 and 0.55 is a high arch, and a ratio between 0.55 and 0.65 is a neutral arch, and the ratio is between 0.55 and 0.65. Those with a ratio between 0.65 and 0.75 have a low arch, while those with a ratio between 0.75 and 1.0 have a flat foot. Taking Fig. 8 as an example, the ratio of the distance from reference point A to reference point C on Fig. 8 to the distance from reference point B to reference point C is 0.77, which is between 0.75 and 1.0, so it can be judged as flat feet; Taking Figure 9 as an example, the ratio of the distance from the reference point A to the reference point C in Figure 9 to the distance from the reference point B to the reference point C is 0.49, which is between 0.45 and 0.55, so it can be judged to be high Arch of the foot.

In addition to analyzing the shape of the foot arch, this embodiment also provides an analysis method of foot pressure distribution. Therefore, the judgment step 7 also includes a foot pressure distribution calculation process 73 and a color table conversion process 74. The foot pressure distribution calculation process 73 is to distinguish the difference values of the result display information into at least two analysis areas, and divide the sum of the differences of each area by the total of the differences of each analysis area to form a difference. Concentration value. Specifically, the sum of differences represents the sum of all the differences in the analysis area; and the total number of differences represents the number of all difference pixels in the analysis area. And taking the sum of the difference concentration value of each analysis area as the denominator, and the difference concentration value of each analysis area as the numerator, calculate the ratio of the difference concentration value of each analysis area to the entire sole, and generate At least one foot pressure distribution ratio is used to analyze the foot pressure distribution of the sole of the foot relative to the pedaling pad 81 by the characteristic that the degree of pressure is proportional to the magnitude of the difference.

Taking Figure 10 as an example, the sole of the foot is analyzed in three analysis areas: the front part of the foot, the middle part of the foot, and the heel. These analysis areas are defined as analysis area A1, analysis area A2, and analysis area A3. After calculation , It can be seen that the foot pressure distribution ratio of the analysis area A1 is 30%, the foot pressure distribution ratio of the analysis area A2 is 15%, and the foot pressure distribution ratio of the analysis area A3 is 55%, which shows that the subject The foot pressure is more concentrated in the heel position. Take Figure 11 as an example. Similarly, the sole of the subject is also analyzed in three analysis areas: the front part of the foot, the middle part of the foot, and the heel. These analysis areas are defined as analysis area B1 and analysis area. B2, and analysis area B3, after calculation, it can be seen that the foot pressure distribution ratio of analysis area B1 is 50%, the foot pressure distribution ratio of the analysis area B2 is 35%, and the foot pressure distribution ratio of the analysis area B3 is 15%, so as to infer that the foot pressure of the subject is more concentrated on the front part of the foot. At this time, the manufacturer can provide suggestions for purchasing shoes or insoles based on the measurement result, and the subject can also adjust the walking or standing posture based on the measurement result.

It is worth mentioning that although the above analysis areas are divided into the front part of the foot, the middle part of the foot, and the heel, it is not limited to this. The analyst can divide according to the direction of the analysis, such as from the inner part. The outer part is divided into the inner part of the sole, the middle part of the sole, and the outer part of the sole, and the ratio of the foot pressure distribution is calculated to calculate the ratio of the foot pressure distribution between different areas. The color table conversion process 74 re-colorizes the result display information in gray scale according to the color table, and combines the values obtained by the aforementioned foot pressure distribution calculation process 73 to facilitate the testee's clear interpretation.

On the other hand, since each time the foot arch measurement method is executed, the pre-comparison step 2 of the stepping pad 81 that has not been stepped on will be rescanned, even if the stepping pad 81 is stepped on multiple times, a little bit that is not easy to be noticed by the naked eye will occur Deformation, the pre-comparison information will also be recorded, so the difference comparison step 5 can still be used to compare the difference in the pixel point difference of the pedaling pad 81 before and after the subject’s stepping on, and exclude some of the above-mentioned differences. For errors caused by deformation, when the stepping pad 81 has deformed visible to the naked eye, it can be replaced.

In summary, the detection unit 83 scans the deformation of the tread pad 81 of special material after being stepped on, and uses the difference to compare step 5 to convert the deformation difference. Convert it into a color gradation difference, and compare the color gradation difference before and after the subject is stepped on, to analyze the deformation of the pedaling pad 81 caused by the pressure of the subject’s arch, and filter out unnecessary by the trimming step 6. After the noise, you can proceed to step 7 of the interpretation to determine the arch shape or calculate the foot pressure distribution. You only need to step on the arch measurement device to easily obtain a clear detection result, so it can be To achieve the purpose of the invention.

However, the above are only examples of the present invention. When the scope of implementation of the present invention cannot be limited by this, all simple equivalent changes and modifications made in accordance with the scope of the patent application of the present invention and the content of the patent specification still belong to This invention patent covers the scope.

1: Preparation steps

2: Pre-control step

3: stepping on steps

4: Image processing steps

41: Grayscale conversion process

42: regularization process

5: Difference comparison steps

6: finishing steps

61: Reverse process

62: Smoothing the process

63: Edge detection process

64: Conversion process

65: Light and shadow elimination process

66: Decrease resolution process

7: Interpretation steps

71: Binarization process

72: Judgment process

73: Foot pressure distribution calculation process

74: Color table conversion process

Claims (7)

A method for measuring the arch of the foot includes: a preparation step of preparing a pedaling mat suitable for a subject to step on and presenting a compressed state, a measuring platform for supporting the pedaling mat, and a measurement platform suitable for scanning the pedaling A detection unit that generates at least one optical image due to the pressure of the pad; a pre-comparison step, using the detection unit to scan the stepping pad to generate a pre-comparison information showing the type of the stepping pad that has not been stepped on; a stepping step, The detection unit is made to scan the deformation of the stepping pad when the subject steps on the stepping pad, and generates a pre-comparison information; an image processing step uses an image processing unit to use the pre-comparison information and the pre-comparison The information is respectively transformed into a comparison information and a comparison information, and includes a gray-scale conversion process for gray-scale conversion, and a normalization process for adjusting hue, saturation and lightness; a difference comparison step to compare the Compare the difference between the comparison information and the comparison information, and generate a result display information with a plurality of color gradation differences showing the comparison information and the comparison information; and an interpretation step to analyze the result display information and determine the testee’s sufficiency Bow shape, and includes a foot pressure distribution calculation process, the foot pressure distribution calculation process is to distinguish the difference between the results display information into at least two analysis areas, and divide the sum of the differences of each analysis area by the each The total number of differences in an analysis area forms a difference concentration value, and the corresponding difference concentration values of the at least two analysis areas are compared. The method for measuring the arch of the foot as described in claim 1, further comprising a further adjustment of the The result shows that the finishing steps of the information include a smoothing process, an edge detection process, and a down-and-up resolution process. The foot arch measurement method according to claim 1 or 2, wherein the interpretation step further includes a binarization process, and the binarization process is to distinguish the differences in the result display information according to a threshold , The differences above the threshold are all marked as a first contrast color, and the differences below the threshold are all marked as a second contrast color different from the first contrast color. The foot arch measurement method according to claim 1 or 2, wherein the interpretation step further includes a color table conversion process for grayscale coloring. The method for measuring the arch of the foot according to claim 3, wherein the interpretation step further includes a determination process, which is determined by the ratio of the distance between the center of the arch of the foot relative to the end of the sole of the foot and the width of the sole of the foot by the result display information Arch type. A foot arch measurement device suitable for performing the foot arch measurement method according to any one of claims 1 to 5, comprising: a stepping pad, made of a combination of polyurethane and non-woven fabric, and suitable for being stepped on by a subject The pressure condition is displayed on the bottom surface; a measurement platform is used to carry the treading mat; a detection unit is suitable for scanning the pressing condition of the treading mat to generate at least one optical image; and an image processing unit is suitable for processing The at least one optical image includes a gray-scale conversion component for performing gray-scale conversion, a difference comparison component for performing difference comparison, and a denoising component for screening out required information. The foot arch measurement device according to claim 6, wherein the measurement platform is a transparent reinforced flat plate.

Images