Foot shape recognition method and device based on planar capacitive sensor array

Abstract

The invention provides a foot shape recognition method and device based on a planar capacitive sensor array, and the method comprises the steps: collecting the position and capacitance value of each sensing unit when a foot intervenes in the planar capacitive sensor array, and forming a capacitance value array diagram; binarizing the capacitance value array diagram, and extracting sensing units corresponding to capacitance values higher than a preset capacitance threshold value as foot region pixel points; calculating a first pixel length, a second pixel length and a pixel area of the foot image; and converting the first pixel length, the second pixel length and the pixel area into the foot length, the foot width and the foot area according to the sensing unit entity size corresponding to the pixel points. According to the invention, different foot forms can be identified based on the planar capacitive sensor array, and personalized application can be provided according to the identified foot forms.

Description

Technical Field

[0001] The present invention mainly relates to the field of capacitive sensing technology, and in particular to a method and device for identifying foot morphology based on a planar capacitive sensor array. Background Art

[0002] With the rapid development of personalized control technology in smart homes, entertainment environments, and commercial venues, how to ensure privacy protection while improving user experience has become a key issue. Although traditional biometric technologies such as face, fingerprint, palm print, and iris recognition have high recognition accuracy, they directly involve users' sensitive biometric data and pose the risk of privacy leakage. In addition, some technologies require users to actively cooperate with recognition, which reduces the convenience of use.

[0003] At present, there are few products on the market that can identify user identities and different age groups without involving personal privacy biometric data and realize personalized functions. Most existing foot recognition systems are limited to basic behavior recognition and simple health monitoring functions, and cannot provide personalized services and experiences. With the development of smart homes and smart public facilities, people have higher and higher demands for personalization and intelligence, and are paying more and more attention to the leakage of personal biometric data. Providing customized services based on user characteristics while being privacy-friendly will greatly improve the user experience. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method and device for identifying foot morphology based on a planar capacitive sensor array, which can identify different foot morphologies based on the planar capacitive sensor array and provide personalized applications according to the identified foot morphologies.

[0005] In order to solve the above technical problems, in the first aspect, the present invention provides a foot morphology recognition method based on a planar capacitive sensor array, comprising: collecting the position and capacitance value of each sensing unit when the foot is involved in the planar capacitive sensor array to form a capacitance value array diagram; Figure 2 The sensor units corresponding to the capacitance values ​​higher than the preset capacitance threshold are extracted as the pixels of the foot area; wherein all the pixels of the foot area constitute the foot image, and one sensor unit corresponds to one pixel point; the first pixel length, the second pixel length and the pixel area of ​​the foot image are calculated; wherein the first pixel length is the longest distance between two pixels in the foot image in the foot length direction, the second pixel length is the longest distance between two pixels in the foot image in the foot width direction, the foot length direction is perpendicular to the foot width direction, and the pixel area is the area size of the foot image; according to the physical size of the sensor unit corresponding to the pixel point, the first pixel length, the second pixel length and the pixel area are converted into the foot length, foot width and foot area of ​​the foot.

[0006] Optionally, the capacitance value array Figure 2 During the quantization process, the pixel points whose capacitance value is less than the capacitance threshold are set as the background color, and the pixel points whose capacitance value is not less than the capacitance threshold are set as the target color.

[0007] Optionally, the method further includes: adjusting the orientation of the foot image so that the foot length direction of the foot image is consistent with the coordinate axis direction of the plane coordinate system.

[0008] Optionally, the foot length direction is parallel to the longitudinal axis of the plane coordinate system, the first pixel length is the difference between the maximum and minimum values ​​of the longitudinal coordinate of each pixel point on the foot image, and the second pixel length is the difference between the maximum and minimum values ​​of the transverse axis coordinate of each pixel point on the foot image.

[0009] Optionally, the foot length direction is obtained by calculating the length between any two pixel points in the foot image, selecting the direction of the straight line formed by the two pixel points with the longest length as the deflection direction, and determining the foot length direction based on the angular relationship between the deflection direction and the foot length direction.

[0010] Optionally, adjusting the orientation of the foot image includes: calculating the angle difference between the foot length direction and the coordinate axis to obtain a rotation angle; and rotating the foot image according to the rotation angle.

[0011] Optionally, the method further includes: extracting a contour of the foot image, wherein the contour is a set of continuous pixel points at the edge of the foot image.

[0012] Optionally, the method further includes: comparing the foot image with a pre-stored foot model, and obtaining the foot type of the foot according to the similarity of the comparison, wherein the foot type includes a left foot and a right foot.

[0013] Optionally, the method further includes: performing validity verification on the foot image to determine whether a ratio of a first pixel length to a second pixel length of the foot image satisfies a set verification threshold.

[0014] Optionally, the method further includes: comparing the calculated foot length, foot width, foot area, and foot length-foot-width ratio with the foot morphology data of different groups of people in the reference foot model to obtain the group of people corresponding to the foot.

[0015] In a second aspect, the present invention provides a foot morphology recognition device based on a planar capacitive sensor array, comprising: a collection module for collecting the position and capacitance value of each sensor unit when the foot is involved in the planar capacitive sensor array to form a capacitance value array map; an extraction module for extracting the capacitance value array Figure 2The sensor unit corresponding to the capacitance value higher than the preset capacitance threshold is extracted as a pixel point in the foot area; wherein all the pixel points in the foot area constitute a foot image, and one sensor unit corresponds to one pixel point; a calculation module is used to calculate the first pixel length, the second pixel length and the pixel area of ​​the foot image; wherein the first pixel length is the longest distance between two pixel points in the foot image in the foot length direction, the second pixel length is the longest distance between two pixel points in the foot image in the foot width direction, the foot length direction is perpendicular to the foot width direction, and the pixel area is the area size of the foot image; a conversion module is used to convert the first pixel length, the second pixel length and the pixel area into the foot length, foot width and foot area of ​​the foot according to the physical size of the sensor unit corresponding to the pixel point.

[0016] In a third aspect, the present invention provides an electronic device comprising: a processor and a memory, wherein the memory stores programs or instructions that can be run on the processor, and when the programs or instructions are executed by the processor, the steps of the foot morphology recognition method based on a planar capacitive sensor array as described in the first aspect are implemented.

[0017] In a fourth aspect, the present invention provides a readable storage medium storing a program or instruction, which, when executed by a processor, implements the steps of the foot morphology recognition method based on a planar capacitive sensor array as described in the first aspect.

[0018] In a fifth aspect, the present invention provides a stepping system, comprising: at least one stepping component, the stepping component comprising a planar capacitive sensor array, a capacitive detection unit and a data processing unit connected in sequence; a control module, the control module being connected to the data processing unit and the control module being used to execute the method described in the first aspect; an output component, the output component being connected to the control module and executing a corresponding output mode according to an output instruction of the control module, the output instruction being dependent on the foot morphology.

[0019] Optionally, the output component includes at least one or more of the following: an audio output component, a visual output component, and a mechanical action output component.

[0020] Compared with the prior art, the present invention has the following advantages: firstly, the position and capacitance value of each sensing unit are collected to form a capacitance value array diagram; then, the capacitance value array diagram is obtained. Figure 2The method converts the capacitance of the foot into values, extracts the sensing units corresponding to the capacitance values ​​higher than the preset capacitance threshold as the pixels of the foot area; calculates the first pixel length, the second pixel length and the pixel area of ​​the foot image; finally, according to the physical size of the sensing unit corresponding to the pixel point, converts the first pixel length, the second pixel length and the pixel area into the foot length, the foot width and the foot area, thereby being able to identify different foot shapes based on the planar capacitive sensor array, and provide personalized applications according to the identified foot shapes. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings are included to provide a further understanding of the present application. They are included and constitute a part of the present application. The accompanying drawings illustrate embodiments of the present application and together with the present specification serve to explain the principles of the present application. In the accompanying drawings:

[0022] Figure 1 is a schematic flow chart of a foot shape recognition method based on a planar capacitive sensor array according to an embodiment of the present invention;

[0023] Figure 2 is a schematic projection diagram of a foot in one embodiment of the present invention;

[0024] Figure 3 is a schematic diagram of a foot image after binarization in one embodiment of the present invention;

[0025] Figure 4 is a schematic diagram of a foot image after adjusting its orientation in one embodiment of the present invention;

[0026] Figure 5 is a schematic diagram of the contour of a foot image extracted in one embodiment of the present invention;

[0027] Figure 6 is a schematic diagram of matching the contour of a foot image with a model foot image in one embodiment of the present invention;

[0028] Figure 7 A schematic diagram of the length and width of a foot in one embodiment of the present invention;

[0029] Figure 8 A schematic diagram of calculating the length and width of a foot in one embodiment of the present invention;

[0030] Fig. 9 A schematic diagram of calculating the foot area of ​​a foot according to an embodiment of the present invention;

[0031] Fig.10 is a schematic structural diagram of a foot shape recognition device based on a planar capacitive sensor array according to an embodiment of the present invention;

[0032] Fig.11 is a schematic diagram of an electronic device according to an embodiment of the present invention;

[0033] Fig.12 is a schematic diagram of the lighting effect of the stepping system in one embodiment of the present invention (piano keys);

[0034] Fig.13 yes Fig.12 A top view of the lighting effect;

[0035] Fig.14 is a schematic diagram of the lighting effect (water drop ripples) of the stepping system in one embodiment of the present invention;

[0036] Fig.15 yes Fig.14 A top view of the lighting effect;

[0037] Fig.16 is a schematic diagram of the lighting effect of the stepping system in one embodiment of the present invention (game);

[0038] Fig.17 yes Fig.16 A top view of the lighting effect;

[0039] Fig.18 is a schematic diagram of the lighting effect of the stepping system in one embodiment of the present invention (stage tracking);

[0040] Fig.19 yes Fig.18 A top view of the lighting effect. DETAILED DESCRIPTION

[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.

[0042] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0043] Flowcharts are used in the present application to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed accurately in order. On the contrary, various steps may be processed in reverse order or simultaneously. At the same time, other operations may be added to these processes, or one or more operations may be removed from these processes.

[0044] Figure 1 FIG. 1 is a flow chart of a method for identifying foot morphology based on a planar capacitive sensor array according to an embodiment of the present invention, with reference to FIG. Figure 1 As shown, the method 100 includes: S110, collecting the position and capacitance value of each sensing unit when the foot is involved in the planar capacitance sensor array to form a capacitance value array diagram; S120, Figure 2 The sensor units corresponding to the capacitance values ​​higher than the preset capacitance threshold are extracted as the pixels of the foot area; wherein all the pixels of the foot area constitute the foot image, and one sensor unit corresponds to one pixel point; S130, calculating the first pixel length, the second pixel length and the pixel area of ​​the foot image; wherein the first pixel length is the longest distance between two pixels in the foot image in the direction of the foot length, the second pixel length is the longest distance between two pixels in the foot image in the direction of the foot width, the foot length direction is perpendicular to the foot width direction, and the pixel area is the area size of the foot image; S140, according to the physical size of the sensor unit corresponding to the pixel point, converting the first pixel length, the second pixel length and the pixel area into the foot length, foot width and foot area of ​​the foot.

[0045] The method of this embodiment can collect foot data in real time, mainly the capacitance value sensed by the planar capacitive sensor array, calculate the biological characteristics of the sole of the foot, such as foot length, foot width and foot area, and then combine the age group division to achieve accurate individual identity recognition. Although the sole features vary with age, these features tend to be stable in the short term or after adulthood, thus becoming an effective basis for identity recognition. By analyzing these foot data, user identity recognition is achieved, and if it cannot be matched to the user database, preliminary recognition is performed based on age group. The method of this embodiment is suitable for smart homes, entertainment environments and commercial places, and can improve user experience and ensure safety.

[0046] In this embodiment, when the foot is placed in the sensitive area of ​​the planar capacitive sensor array, the capacitance value in the area will increase. By collecting and recording the capacitance value of each sensing unit (or sensing point or sensor), the projection image of the foot on the planar capacitive sensor array can be captured to form a capacitance value array diagram.

[0047] When the foot is involved in the planar capacitive sensor array, it not only affects the sensor unit in the positive projection area of ​​the foot, but also in the surrounding area adjacent to the foot. As for the capacitance value generated by each sensor unit, a certain capacitance value will also be generated around the foot area. Therefore, the actual situation is that the area generating the capacitance value collected by the planar capacitive sensor array includes the foot area and the area adjacent to the foot area. On the other hand, since the area adjacent to the foot area is subject to the additional influence of the foot, its capacitance value is smaller than that of the foot area. According to this feature, this embodiment binarizes the acquired capacitance value array diagram, extracts the sensing unit corresponding to the capacitance value higher than the preset capacitance threshold as the pixel point of the foot area, and filters out the area with a capacitance value less than the capacitance threshold, so that the foot area is separated from the background area, so that the extracted area is basically the foot area. The capacitance threshold is a set threshold for distinguishing the foot area from the area adjacent to the foot area, which can be selected according to the actual situation. An adaptive threshold algorithm can also be used to ensure that the foot area can be correctly extracted under different foot pressures, thereby providing a clear image basis for subsequent processing. In this embodiment, one sensor unit corresponds to one pixel. Of course, the resolution of the image depends on the size of the single sensor unit and the number of sensor units in the planar capacitive sensor array. The smaller the area of ​​the single sensor unit and the greater the number of sensor units, the richer the image details of the foot area obtained.

[0048] In this embodiment, after the foot image is acquired, since the foot image is based on each sensing unit corresponding to a pixel point, the first pixel length, the second pixel length and the pixel area can be calculated. In addition, the physical size represented by each pixel point is known, that is, it represents the size of the sensing unit in the planar capacitive sensor array. For example, if the size of each sensing unit is 6mm*6mm, then one pixel represents 6mm*6mm. Therefore, the first pixel length, the second pixel length and the pixel area can be converted into the foot length, foot width and foot area of ​​the foot according to the physical size of the sensing unit corresponding to the pixel point.

[0049] In this embodiment, method 100 may also include preprocessing the capacitance value array diagram, specifically including noise removal and image enhancement (i.e., amplification processing). The collected capacitance value signal is subjected to noise reduction and amplification processing to filter out environmental noise and enhance foot motion signals to ensure the accuracy of subsequent analysis and calculation. Exemplarily, in order to improve the clarity of the foot image contour, a median filter may be used to remove noise in the image, and then a Canny edge detection algorithm may be used to extract the external contour of the foot for further analysis and processing.

[0050] In one example, for a capacitance array Figure 2During the quantization process, the pixels whose capacitance values ​​are less than the capacitance threshold are set as the background color, and the pixels whose capacitance values ​​are not less than the capacitance threshold are set as the target color.

[0051] refer to Figure 3 As shown, a capacitance threshold T is set to distinguish the foot recognition area from the non-recognition area. The sensing unit with a capacitance value higher than the capacitance threshold T is regarded as the foot coverage area. All pixels in the capacitance array diagram with a capacitance value less than the capacitance threshold T are set to white (background color), and the rest are set to black or gray (target color). The black area or gray area is the foot area.

[0052] In one example, the method 100 further includes adjusting the orientation of the foot image so that the foot length direction of the foot image is consistent with the coordinate axis direction of the plane coordinate system.

[0053] In general, the coordinate system of the capacitance value array diagram recorded in this embodiment is a plane coordinate, and the horizontal and vertical axes of the coordinate system correspond to the length and width of the planar capacitance sensor array. When the foot steps into the planar capacitance sensor array, the foot length direction of the foot is parallel to the length or width direction of the planar capacitance sensor array (that is, the foot length direction of the foot image is parallel to the vertical axis or the horizontal and vertical axes). It is relatively rare. In most cases, all directions exist, and the randomness is strong. In the conventional foot length and foot width calculation method, the first pixel length is the longest distance between two pixels in the foot image in the foot length direction, and the second pixel length is the longest distance between two pixels in the foot image in the foot width direction. This calculation method has a certain complexity. Therefore, in order to simplify the calculation of the first pixel length and the second pixel length of this embodiment, the foot image can be rotated to a direction parallel to the coordinate axis of the coordinate system. In this case, the foot parameters such as foot length and foot width can be calculated more easily.

[0054] In one example, the foot length direction is parallel to the ordinate axis of the plane coordinate system, and the first pixel length is the difference between the maximum and minimum values ​​of the ordinate coordinates of each pixel point on the foot image, and the second pixel length is the difference between the maximum and minimum values ​​of the ordinate coordinates of each pixel point on the foot image. Figure 8 As shown, the foot length is calculated as follows: calculate the difference between the maximum and minimum values ​​of the foot contour point set in the y-axis direction, that is, foot_length = max(yi)-min(yi). The foot width is calculated as follows: calculate the difference between the maximum and minimum values ​​of the foot contour point set in the x-axis direction, that is, foot_width = max(xi)-min(xi).

[0055] In one example, the foot length direction is obtained by calculating the length between any two pixel points in the foot image, selecting the straight line direction formed by the two pixel points with the longest length as the deflection direction, and determining the foot length direction based on the angular relationship between the deflection direction and the foot length direction.

[0056] Reference again Figure 3 As shown, A in the figure represents the deflection direction, and L represents the foot length direction. After receiving the data of the planar capacitive sensor array, the foot image is determined, and it is easy to calculate the distance or length between any two pixels in the foot image area. Among these sets, the longest distance can be queried, such as the pixel m and pixel n on the edge of the foot image in the direction A in the figure. The deflection direction A direction of the current foot image can be determined by pixel m and pixel m. In addition, it can also be known that the foot length direction and the deflection direction have a definite relationship, and their angle difference is set to a. Even if the angle difference is slightly different in actual conditions, it can be fine-tuned or corrected, which does not affect the understanding of the substantive content of this embodiment. Based on this, the foot length direction can be determined according to the angular relationship (angle difference a) between the deflection direction and the foot length direction.

[0057] In one example, adjusting the orientation of the foot image includes calculating an angular difference between the foot length direction and the longitudinal coordinate axis to obtain a rotation angle, and rotating the foot image according to the rotation angle.

[0058] For example, Figure 3 The deflection direction A of the foot image is obtained, and the foot length direction L can be obtained by combining the difference of the angle difference a between the foot length direction L and the deflection direction A. At this time, the L direction intersects with the coordinate axis (such as the longitudinal axis). In order to make the subsequent calculation of foot parameters such as foot length and foot width easier, the foot length direction L is adjusted in this embodiment so that the foot length direction L is parallel to the longitudinal coordinate axis. Then, the first pixel length is the difference between the maximum value and the minimum value of the longitudinal axis coordinate of each pixel point on the foot image, and the second pixel length is the difference between the maximum value and the minimum value of the horizontal axis coordinate of each pixel point on the foot image.

[0059] In one example, the method 100 further includes extracting a contour of the foot image, where the contour is a set of pixels with continuous edges of the foot image.

[0060] As mentioned above, when the foot steps into the planar capacitive sensor array, not only the foot area will generate a capacitance value, but also a part of the area adjacent to the foot area will generate a capacitance value. Therefore, the present embodiment can extract the foot area accordingly. In another case, due to the different foot features of each person, such as different degrees of arch curvature, or even if it is the same person, but the stepping method of the planar capacitive sensor array is different, it is possible that there is a capacitance value in the foot area that is less than the capacitance threshold. In this case, the foot area calculated in the above manner will produce an error, that is, the area where the foot contacts the planar capacitive sensor array is not the actual projection area of ​​the foot. The present embodiment also notes another point, although there is a case where the capacitance value in the arch area is less than the capacitance threshold, the capacitance value at the outer edge of the foot area is basically greater than the capacitance threshold, so the outer edge can reflect the overall situation of the foot area. Based on this, in order to more accurately calculate the foot length, foot width and foot area, especially the foot area, the present embodiment extracts the contour of the foot image, and the size of the foot area can be directly determined based on this contour, and then the foot area is calculated.

[0061] In this embodiment, the Canny edge detection can be used to calculate the gradient of the image to find the most significant areas of change, which usually represent the boundaries of the object. In the foot image, these boundaries represent the contours of the foot image. That is, contour extraction is to extract closed edge lines in the binary image. You can also use the OpenCV function findContours() to find contours. This function retrieves all contours in the image and returns them in the form of a vector, each contour is a continuous set of pixels.

[0062] In one example, method 100 further includes comparing the foot image with a pre-stored foot model, and obtaining the foot type according to the similarity of the comparison, where the foot type includes a left foot and a right foot.

[0063] Exemplary, reference Figure 6 As shown, to verify whether the foot image is valid foot data and determine whether it is a left foot or a right foot, the following methods can be used: 1. Template (or model) matching: Pre-store typical left and right foot template images. Use image matching technology (such as cross correlation, normalized correlation, etc.) to compare the similarity between the input foot image and the pre-stored template. 2. Left / right foot identification: Compare the matching scores with the left foot template and the right foot template. A higher score indicates that the foot image is more likely to belong to this category (left foot or right foot).

[0064] In one example, method 100 also includes verifying the validity of the foot image to determine whether the ratio of the first pixel length to the second pixel length of the foot image meets the set verification threshold. For example, by setting a threshold to determine whether the similarity of the match is high enough, generally a corresponding verification threshold is set for comparison to confirm that it is a valid foot image. In this embodiment, the definition of foot length and width can be quoted from the national standard GB / T43293-2022 for shoe size. The foot length is the maximum horizontal distance from the center point of the rear end of the heel (heel protrusion) to the front end of the toe when the test person is barefoot or wearing thin socks that do not obviously affect the foot size, maintaining an upright posture, and evenly distributing weight on both feet. The foot width is the horizontal distance between the lateral protrusion of the first metatarsal bone to the lateral protrusion of the fifth metatarsal bone on the foot under the same conditions as the foot length measurement.

[0065] In one example, method 100 further includes comparing the calculated foot length, foot width, foot area, and foot length / foot width ratio with foot morphology data of different groups of people in a reference foot model to obtain the group of people corresponding to the foot.

[0066] Exemplarily, the areas of all sensor units in the closed area of ​​the foot image are accumulated to obtain the total area of ​​the foot. Further, by calculating the characteristic information such as foot length, width, area, foot length / width ratio, etc., cross-checking the reference foot model data, matching to the corresponding age group. The area of ​​a single sensor unit usually depends on the layout of the planar sensor array and the size of each sensor unit.

[0067] A small number of features on the sole of the foot can be used to preliminarily identify the age group of an individual. When the foot data obtained is not comprehensive enough, it can also provide an indication of the approximate age range of the individual. Generally speaking, during childhood and adolescence, the foot length and width are smaller. At the same time, the foot length and width are in the development stage, the arch of the foot is not fully formed, and the contact area of ​​the sole of the foot is larger. The foot contour is more rounded during this period. As the age increases, the arch of the foot gradually rises and the contact area becomes smaller. After adulthood, the foot length and width are larger. At the same time, the foot length and width tend to be stable, the arch of the foot matures, and the contact pattern is more concentrated in the heel and forefoot area. The arch part is obviously suspended, forming a typical adult sole contact distribution pattern. Due to the degeneration of the soft tissue on the sole of the foot and the descent of the arch, the contact area may increase again in the elderly, especially in the arch area. The foot contour may also change due to the collapse of the arch and the deformation of the toes.

[0068] When complete foot data is collected, the biological characteristics of the foot can accurately identify the identity of an individual. Each person's foot plantar morphology and contact distribution have subtle but significant differences, and these differences can be used for high-precision identity authentication. For example, 1) Unique combination of foot length and foot width: The combination of foot length and foot width varies significantly between different individuals. Even if two people have the same foot length, their foot width may be different. The combination of these two parameters can be used to initially filter individuals and provide a basis for identity recognition. 2) Uniqueness of foot contour: Each person's foot contour is unique, and the length, distribution, arch height and heel shape of the toes can all be used as markers for individual identification. Contour data provides a high-precision "plantar fingerprint" that can effectively distinguish individuals. 3) Detailed differences in plantar contact distribution: Details such as contact distribution pattern, pressure concentration points, and arch status are all individualized features. Even if two individuals have similar foot length and foot width, their contact distribution will show significant differences due to different arch morphology and gait. Such subtle differences can provide high-precision support in the identity recognition process.

[0069] By analyzing the length, width, shape and distribution of sole contact of the foot, the age of the current person can be preliminarily identified, and then high-precision identity recognition can be achieved through the collection of complete data. These sole features have significant individual differences and can provide long-term and reliable basis for identity verification.

[0070] For example, if the size of the sensing unit represented by each pixel is 6mm*6mm, according to statistical data, different age groups have different foot length / foot width ratios. Fig. 9 The following are the foot areas of infants, toddlers, children, and teenagers / adults. Usually, the foot length / width ratio of minors is between 2.0 and 2.5, while that of adults is between 2.3 and 3.0. In one application, by comparing the foot length / foot width ratio, it is determined whether the foot is a full foot.

[0071] In this embodiment, the age group comparison table can be preset or completely customized by the user. Preset means that based on the shoe size standard GBT / 36935-2018 / ISO / TS19407:2015, combined with statistical data, users are divided into different age groups and a size age group comparison table is pre-established. As shown in Table 1, the preset age group comparison table is divided into four age groups: infants, toddlers, children, and teenagers / adults. Each sensing unit corresponding to each pixel has an area of ​​6mm*6mm.

[0072] Table 1 Foot parameters in different age groups

[0073]

[0074] In this embodiment, there are two methods for customizing the age group comparison table: first, in the preset mode, the user modifies the local parameters to form a new comparison table; second, the user collects foot images and enters data on site, and uses this as a sample to generate a new comparison table.

[0075] This embodiment of the foot shape recognition method based on the planar capacitive sensor array first collects the position and capacitance value of each sensor unit to form a capacitance value array map; then Figure 2 The sensor units corresponding to the capacitance values ​​higher than the preset capacitance threshold are extracted as the pixels in the foot area; the first pixel length, the second pixel length and the pixel area of ​​the foot image are calculated; finally, according to the physical size of the sensor unit corresponding to the pixel point, the first pixel length, the second pixel length and the pixel area are converted into the foot length, foot width and foot area of ​​the foot, so that different foot shapes can be identified based on the planar capacitive sensor array, and personalized applications can be provided based on the identified foot shapes. Compared with traditional biometric recognition technologies such as face, fingerprint, palm print, and iris recognition, foot data (including foot length, foot width, external contour and sole contact) are privacy-friendly and individual biological features, which can be effectively collected through the planar capacitive sensor array and can be recognized without the user's active participation.

[0076] Another embodiment of the present invention provides a foot morphology recognition device 1000 based on a planar capacitive sensor array, which mainly includes: a collection module 1001, which is used to collect the position and capacitance value of each sensor unit when the foot is involved in the planar capacitive sensor array to form a capacitance value array map; an extraction module 1002, which is used to extract the capacitance value array Figure 2 The sensor unit corresponding to the capacitance value higher than the preset capacitance threshold is extracted as the pixel point of the foot area; wherein all the pixel points of the foot area constitute the foot image, and one sensor unit corresponds to one pixel point; a calculation module 1003 is used to calculate the first pixel length, the second pixel length and the pixel area of ​​the foot image; wherein the first pixel length is the longest distance between two pixel points in the foot image in the foot length direction, the second pixel length is the longest distance between two pixel points in the foot image in the foot width direction, the foot length direction is perpendicular to the foot width direction, and the pixel area is the area size of the foot image; a conversion module 1004 is used to convert the first pixel length, the second pixel length and the pixel area into the foot length, foot width and foot area of ​​the foot according to the physical size of the sensor unit corresponding to the pixel point.

[0077] In one example, for a capacitance array Figure 2 During the quantization process, the pixels whose capacitance values ​​are less than the capacitance threshold are set as the background color, and the pixels whose capacitance values ​​are not less than the capacitance threshold are set as the target color.

[0078] In one example, an adjustment module is further included: used to adjust the orientation of the foot image so that the foot length direction of the foot image is consistent with the coordinate axis direction of the plane coordinate system.

[0079] In one example, the foot length direction is parallel to the ordinate axis of the plane coordinate system, the first pixel length is the difference between the maximum and minimum values ​​of the ordinate coordinate of each pixel point on the foot image, and the second pixel length is the difference between the maximum and minimum values ​​of the ordinate coordinate of each pixel point on the foot image.

[0080] In one example, the foot length direction is obtained by calculating the length between any two pixel points in the foot image, selecting the straight line direction formed by the two pixel points with the longest length as the deflection direction, and determining the foot length direction based on the angular relationship between the deflection direction and the foot length direction.

[0081] In one example, adjusting the orientation of the foot image includes: calculating the angle difference between the foot length direction and the longitudinal coordinate axis to obtain a rotation angle; and rotating the foot image according to the rotation angle.

[0082] In one example, a contour extraction module is also included: used to extract the contour of the foot image, where the contour is a set of continuous pixel points on the edge of the foot image.

[0083] In one example, a comparison module is also included: used to compare the foot image with a pre-stored foot model, and obtain the foot type according to the similarity of the comparison, and the foot type includes a left foot and a right foot.

[0084] In one example, a verification module is further included: used to verify the validity of the foot image and determine whether the ratio of the first pixel length to the second pixel length of the foot image meets a set verification threshold.

[0085] In one example, a comparison module is also included: used to compare the calculated foot length, foot width, foot area, foot length-foot width ratio with the foot shape data of different groups of people in the reference foot model to obtain the group of people corresponding to the foot.

[0086] The details of other operations performed by each module in this embodiment can be referred to the aforementioned embodiments and will not be elaborated here.

[0087] The foot shape recognition device based on the planar capacitive sensor array in this embodiment first collects the position and capacitance value of each sensor unit to form a capacitance value array map; then Figure 2The sensor units corresponding to the capacitance values ​​higher than the preset capacitance threshold are extracted as the pixels in the foot area; the first pixel length, the second pixel length and the pixel area of ​​the foot image are calculated; finally, according to the physical size of the sensor unit corresponding to the pixel point, the first pixel length, the second pixel length and the pixel area are converted into the foot length, foot width and foot area of ​​the foot, so that different foot shapes can be identified based on the planar capacitive sensor array, and personalized applications can be provided based on the identified foot shapes. Compared with traditional biometric recognition technologies such as face, fingerprint, palm print, and iris recognition, foot data (including foot length, foot width, external contour and sole contact) are privacy-friendly and individual biological features, which can be effectively collected through the planar capacitive sensor array and can be recognized without the user's active participation.

[0088] Another embodiment of the present invention provides a stepping system, comprising: at least one stepping component, a control module and an output component, wherein the stepping component includes a planar capacitive sensor array, a capacitance detection unit and a data processing unit connected in sequence; the control module is connected to the data processing unit, and the control module is used to execute the foot morphology recognition method based on the planar capacitive sensor array as described in the aforementioned embodiment; the output component is connected to the control module, and executes a corresponding output mode according to the output instruction of the control module, and the output instruction depends on the foot morphology.

[0089] The planar capacitive sensor array can be installed on the floor of a home entrance, bedroom, corridor or living room, and generates a two-dimensional foot image by detecting the capacitance between the foot and the surface of the planar capacitive sensor array. The planar capacitive sensor array has high resolution and sensitivity, and can accurately capture the pressure distribution of the foot.

[0090] In one example, the output component includes at least one or more of the following: an audio output component, a visual output component, and a mechanical motion output component.

[0091] The details of other operations performed by each module in this embodiment can be referred to the aforementioned embodiments and will not be elaborated here.

[0092] For example, based on the age group identified by the foot analysis, combined with the left / right foot information, a personalized application control function customized by the user is executed. Taking the stepping system as an example, the corresponding application control lighting mode is called according to the identified different age groups and left / right foot information.

[0093] 1. Keyboard mode, reference Figure 12-13

[0094] For babies aged 0-1, the stepping system's piano-mode lighting is designed to stimulate their early sensory development and curiosity. At this age, babies begin to develop basic perception and cognition of the world around them. The piano-mode creates a dynamic learning environment by transforming each step into an interactive light and sound unit.

[0095] When the baby's feet touch the steps, the corresponding lights will light up like piano keys and make pleasant sounds. This combination of sight and sound not only attracts the baby's attention, but also helps them understand the connection between action and reaction, thereby deepening their understanding of cause and effect. As the light changes and the music plays, babies are encouraged to move and explore, which is a key part of their cognitive development. By creating such a safe and stimulating environment, the piano mode provides an attractive multi-sensory experience for babies aged 0-1, greatly enriching their daily environment, and every walk becomes an educational and entertaining adventure, which has a positive impact on the baby's overall development.

[0096] 2. Water drop ripple mode, reference Figure 14-15

[0097] For children aged 1 to 5, the water droplet ripple pattern of the stepping system provides an interactive experience that is both safe and educational. When this mode is activated, a series of concentric halos radiate outward from the footsteps. As the children walk and run, these halos will change in real time with their movements, with different shapes, creating a dynamic visual spectacle that can produce visual surprises and beauty, and stimulate children's imagination and desire to explore. When children walk or play together in the corridor, the interactivity of the halos not only increases the fun of corridor lighting, but also encourages social interaction and group games. In addition, this mode is also equipped with basic lighting functions. During walking, the brightness of the three steps in front will be reduced in turn. The changes in light are synchronized with the movement of the children's feet, ensuring the safety of each step and illuminating the path forward for the children.

[0098] 3. Game interaction mode, reference Figure 16-17

[0099] For children aged 6 to 13, the game interaction mode of the stepping system provides a platform full of creativity and fun. In this mode, the sensor unit directly serves as the input device for the interactive game. Children can interact with the game through physical movements such as walking and jumping, and even create music together in their steps. The signal triggered by the steps is converted into a specific instrument sound and played through the streaming speaker, providing children with a unique music experience. The intelligent stepping system with game function not only greatly enriches the entertainment attributes of the corridor, but also provides a fun interactive space, turning the daily corridor walk into a novel art creation and game experience. It effectively stimulates children's creativity and enthusiasm for participation, transforming the corridor space into a dynamic scene that integrates entertainment, art creation and social interaction. Through this interactive method, children can not only learn and develop social skills in play, but also find their own voice and rhythm in creative expression, making every step full of surprises and the fun of exploration.

[0100] 4. Stage tracking mode, reference Figure 18-19

[0101] For teenagers and adults over 14 years old, the lighting-based stage tracking mode of the step system focuses on providing the best lighting effects, while enhancing the safety and visual interaction experience of the corridor. This mode imitates the effect of spotlights on professional stages that automatically adjust as the actors move, tracking the position of pedestrians in the corridor in real time, and dynamically adjusting the brightness of the step atmosphere lights to create a lighting effect that guides sightlines and focuses attention.

[0102] When you step onto a step, the ambient light of that step will automatically adjust to the highest brightness point, making it the focus of lighting, as if it is the protagonist under the spotlight, while ensuring sufficient light to ensure walking safety. In addition, the ambient light brightness of the second step in front of the pedestrian and the step behind the pedestrian is adjusted to the lowest, creating a sense of depth with a strong contrast between light and dark, which not only increases the directionality and guidance of the route, but also further ensures the safety of the path ahead. The ambient light brightness of the first step in front of the pedestrian is between the current step and the second step in front, forming a smooth transition, which not only enhances the visual effect, but also avoids the discomfort that may be caused by sudden changes in light.

[0103] This carefully designed brightness adjustment and spatial arrangement not only enhances the aesthetic value and modernity of the corridor, but also significantly enhances the fun and interactivity of the lighting system. Through these innovative designs, the stage tracking mode ensures that the lighting is not only creative and vivid, but also practical and safe, making the corridor lighting no longer monotonous and boring, but an innovative element that adds fun and beauty to life. This clever use of brightness and space not only beautifies the corridor space, but also provides users with an immersive walking experience, and each walk is a visual and emotional feast.

[0104] The above modes are some specific applications of the stepping system of this embodiment. It can be understood that foot recognition itself can also have other applications. The technology of identifying different age groups can be applied to various other modes or fields, especially in the field of smart home, which has huge personalized needs. For example, after identifying the age group of the user, the lighting mode is automatically adjusted according to the different age groups. For children, soft and colorful lights are provided to promote rest and entertainment; for adults, bright and comfortable lighting is provided to improve the comfort of work and life.

[0105] The stepping system of this embodiment obtains the foot image of the foot in the projection area of ​​the planar capacitive sensor array, identifies the foot shape, and determines different age groups to control and execute personalized applications. In particular, in the stepping system, different stepping atmosphere light display modes can be called out using the different age levels identified. For example, when a child is identified, an interesting and entertaining atmosphere display effect can be called, and when an adult is identified, a lighting-based effect can be called. This innovative personalized function will significantly enhance the user's interactive experience and satisfaction.

[0106] A foot morphology recognition device based on a planar capacitive sensor array in an embodiment of the present application may be a device, or a component, an integrated circuit, or a chip in a terminal. A foot morphology recognition device based on a planar capacitive sensor array in an embodiment of the present application may be a device with an operating system. The operating system may be an Android operating system, an iOS operating system, or other possible operating systems, which are not specifically limited in the embodiments of the present application.

[0107] The present application also provides an electronic device, comprising: a memory for storing programs or instructions executable by a processor; and a processor for executing the above-mentioned programs or instructions to implement the various processes of the above-mentioned foot morphology recognition method embodiment based on a planar capacitive sensor array, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0108] Fig.111 is a schematic diagram of an electronic device according to an embodiment of the present invention. The electronic device 1100 may include an internal communication bus 1101, a processor 1102, a read-only memory (ROM) 1103, a random access memory (RAM) 1104, and a communication port 1105. When applied to a personal computer, the electronic device 1100 may also include a hard disk 1106. The internal communication bus 1101 can realize data communication between components of the electronic device 1100. The processor 1102 can make judgments and issue prompts. In some embodiments, the processor 1102 can be composed of one or more processors. The communication port 1105 can realize data communication between the electronic device 1100 and the outside. In some embodiments, the electronic device 1100 can send and receive information and data from the network through the communication port 1105. The electronic device 1100 may also include different forms of program storage units and data storage units, such as a hard disk 1106, a read-only memory (ROM) 1103 and a random access memory (RAM) 1104, which can store various data files used for computer processing and / or communication, as well as possible programs or instructions executed by the processor 1102. The results processed by the processor 1102 are transmitted to the user device through the communication port 1105 and displayed on the user interface.

[0109] The above-mentioned foot shape recognition method based on planar capacitive sensor array can be implemented as a computer program, stored in the hard disk 1106, and can be recorded in the processor 1102 for execution to implement any one of the foot shape recognition methods based on planar capacitive sensor array in the present application.

[0110] An embodiment of the present application also provides a readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, each process of the above-mentioned foot morphology recognition method embodiment based on a planar capacitive sensor array is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0111] For those skilled in the art, the above invention disclosure is only used as an example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.

[0112] Although the present application has been described with reference to the current specific embodiments, ordinary technicians in this technical field should recognize that the above embodiments are only used to illustrate the present application, and various equivalent changes or substitutions may be made without departing from the spirit of the present application. Therefore, as long as the changes and modifications to the above embodiments are within the essential spirit of the present application, they will fall within the scope of the claims of the present application.

Claims

1. A foot morphology recognition method based on a planar capacitive sensor array, characterized in that: include: Collecting the position and capacitance value of each sensing unit when the foot is involved in the planar capacitance sensor array to form a capacitance value array diagram; Binarizing the capacitance value array map, extracting the sensing units corresponding to the capacitance values ​​higher than the preset capacitance threshold as the pixel points of the foot area; wherein all the pixel points of the foot area constitute the foot image, and one sensing unit corresponds to one pixel point; Calculating a first pixel length, a second pixel length, and a pixel area of ​​the foot image; wherein the first pixel length is the longest distance between two pixels in the foot image in a foot length direction, the second pixel length is the longest distance between two pixels in the foot image in a foot width direction, the foot length direction is perpendicular to the foot width direction, and the pixel area is the area size of the foot image; According to the physical size of the sensing unit corresponding to the pixel point, the first pixel length, the second pixel length and the pixel area are converted into the foot length, foot width and foot area of ​​the foot.

2. The method for foot shape recognition based on a planar capacitive sensor array as claimed in claim 1, characterized in that: During the binarization of the capacitance value array graph, the pixel points whose capacitance values ​​are less than the capacitance threshold are set as the background color, and the pixel points whose capacitance values ​​are not less than the capacitance threshold are set as the target color.

3. The method for foot shape recognition based on a planar capacitive sensor array as claimed in claim 1, characterized in that: Also includes: The orientation of the foot image is adjusted so that the foot length direction of the foot image is consistent with the coordinate axis direction of the plane coordinate system.

4. The method for foot shape recognition based on a planar capacitive sensor array as claimed in claim 3, characterized in that: The foot length direction is parallel to the vertical axis of the plane coordinate system, the first pixel length is the difference between the maximum and minimum values ​​of the vertical axis coordinates of each pixel point on the foot image, and the second pixel length is the difference between the maximum and minimum values ​​of the horizontal axis coordinates of each pixel point on the foot image.

5. The method for foot shape recognition based on a planar capacitive sensor array as claimed in claim 3, characterized in that: The foot length direction is obtained by calculating the length between any two pixel points in the foot image, selecting the straight line direction formed by the two pixel points with the longest length as the deflection direction, and determining the foot length direction based on the angular relationship between the deflection direction and the foot length direction.

6. The method for foot shape recognition based on a planar capacitive sensor array as claimed in claim 5, characterized in that: Adjusting the orientation of the foot image includes: calculating the angle difference between the foot length direction and the coordinate axis to obtain a rotation angle; and rotating the foot image according to the rotation angle.

7. The method for foot shape recognition based on a planar capacitive sensor array as claimed in claim 1, characterized in that: Also includes: The contour of the foot image is extracted, where the contour is a set of continuous pixel points at the edge of the foot image.

8. The method for foot shape recognition based on a planar capacitive sensor array as claimed in claim 7, characterized in that: Also includes: The foot image is compared with a pre-stored foot model, and the foot type of the foot is obtained according to the similarity of the comparison, and the foot type includes a left foot and a right foot.

9. The method for foot shape recognition based on a planar capacitive sensor array as claimed in claim 1, characterized in that: Also includes: The validity of the foot image is verified to determine whether a ratio of a first pixel length to a second pixel length of the foot image satisfies a set verification threshold.

10. The method for foot shape recognition based on a planar capacitive sensor array as claimed in claim 1, characterized in that: Also includes: By comparing the calculated foot length, foot width, foot area, and foot length / foot width ratio with the foot morphology data of different groups of people in the reference foot model, the group of people corresponding to the foot is obtained.

11. A foot shape recognition device based on a planar capacitive sensor array, characterized in that: include: A collection module, used to collect the position and capacitance value of each sensing unit when the foot is involved in the planar capacitance sensor array, and form a capacitance value array map; An extraction module, used for binarizing the capacitance value array map, extracting the sensing units corresponding to the capacitance values ​​higher than the preset capacitance threshold as the pixels of the foot area; wherein all the pixels of the foot area constitute the foot image, and one sensing unit corresponds to one pixel; a calculation module, configured to calculate a first pixel length, a second pixel length, and a pixel area of ​​the foot image; wherein the first pixel length is the longest distance between two pixels in the foot image in a foot length direction, the second pixel length is the longest distance between two pixels in the foot image in a foot width direction, the foot length direction is perpendicular to the foot width direction, and the pixel area is the area size of the foot image; A conversion module is used to convert the first pixel length, the second pixel length and the pixel area into the foot length, foot width and foot area of ​​the foot according to the physical size of the sensing unit corresponding to the pixel point.

12. An electronic device, characterized in that: include: A processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the foot morphology recognition method based on a planar capacitive sensor array as described in any one of claims 1 to 10 are implemented.

13. A readable storage medium, characterized in that: The readable storage medium stores a program or instruction, and when the program or instruction is executed by the processor, the steps of the foot morphology recognition method based on a planar capacitive sensor array are implemented as described in any one of claims 1-10.

14. A stepping system, characterized in that: include: At least one step assembly, the step assembly comprising a planar capacitive sensor array, a capacitive detection unit and a data processing unit connected in sequence; A control module, the control module is connected to the data processing unit, and the control module is used to execute the method according to any one of claims 1 to 10; An output component is connected to the control module and executes a corresponding output mode according to an output instruction of the control module, wherein the output instruction depends on the foot shape.

15. A stepping system according to claim 14, characterized in that: The output component includes at least one or more of the following: an audio output component, a visual output component, and a mechanical action output component.

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