Portable shoe tree rear body bridge position measuring method

Abstract

The invention relates to the technical field of shoe trees, and discloses a portable shoe tree rear body bridge site measuring method, which comprises the following steps: taking rear body bridge site information with the highest proportion as rear body bridge site information of a mother last corresponding to the heel height, and manufacturing the mother last; manufacturing a curved surface reference surface of a rear body bridge position measurer according to a rear body bottom plate curved surface of the mother last, and embedding a plurality of pressure sensors in the bottom surface of the rear body bridge position measurer; a mother last is placed on the upper portion of the rear body bridge position measurer, and standard pressure distribution information is collected through a pressure sensor; the rear body bridge position measurer is placed at the bottom of a to-be-measured shoe tree, fitting image information of the rear body bridge position measurer and the bottom of the shoe tree and pressure distribution information collected by the pressure sensor are collected, the fitting degree is calculated according to the fitting image information and the pressure distribution information, and the standard degree of the shoe tree is obtained according to the fitting degree. According to the invention, not only are the accuracy and efficiency of measurement improved, but also the comfort and suitability of the shoe tree can be better reflected.

Description

Technical Field

[0001] The invention relates to the technical field of shoe lasts, and in particular to a method for measuring a rear bridge position of a portable shoe last. Background Art

[0002] The importance of the shoe last back sole standard is reflected in: (1) Structural design basis: The shoe last bottom template is an important reference for footwear structural design, providing designers with a basic template for designing the sole, heel, midsole, and insole; (2) Ensuring comfort: The correct shoe last bottom can ensure that the size and shape of the shoe are suitable for the foot shape of different users, thereby providing better comfort and support; (3) Improving production efficiency: Standardized shoe last bottoms help improve efficiency in the production process because they can be quickly copied and applied to large-scale production; (4) Ensuring product quality: Following the standard shoe last bottom can ensure the consistency of product quality and reduce shoe quality problems caused by inaccurate last shapes. In summary, the shoe last bottom standard is crucial to ensuring the design quality, production efficiency, and consumer comfort of shoes. The important points of the back sole inspection are the heel convexity and the sole convexity.

[0003] There are two existing technical detection methods, one is the national detection method, and the other is the handmade standard pallet detection. The national standard detection method includes two operating methods: (1) Measurement of heel center convexity: The reference points for measuring the heel center convexity are the outer edge point and the inner edge point of the heel center, that is, the line connecting the inner and outer edge points of the heel center is used as the reference to measure the degree of convexity at the heel center convexity position. A vernier caliper is used in conjunction with a steel ruler. The measuring points are M, M2, and M. When operating, fix the shoe last on your back and align the two measuring points M and M2 with the two measuring feet of the vernier caliper. Then place the small steel ruler on the heel center convexity point M and stick it vertically on the caliper to read the height value between the steel ruler and the caliper. After subtracting the height of the steel ruler from the height value of the measuring foot, the heel center convexity value can be obtained. The dotted line in the figure is the reference line for measurement. Note: The measurement of the heel center convexity has nothing to do with the heel center convexity point M. (2) Bottom center convexity: The reference points for measuring the bottom center concavity are the forefoot convexity point and the heel center convexity point, that is, the degree of concavity at the waist position is measured based on the line connecting the heel center convexity point and the forefoot convexity point. Use a vernier caliper in conjunction with a steel ruler. The measuring points are W, M and the waist width line, see the figure. When operating, fix the shoe last on your back, align the two measuring feet of the vernier caliper with the two points M and W, then place the small steel ruler at the waist width line and stick it vertically on the caliper, and read the height value between the steel ruler and the caliper. Subtract the height of the measuring foot from the height value of the steel ruler to get the bottom center concavity value. The manual measurement card is a standard sample made according to the last shape design. It is a fixture in the shoe last design, used to measure and compare the last contour, thereby completing the production of the standard sample last. The cardboard is divided into bottom arc card, last bottom horizontal arc card, rear arc card, side body card, and overall card. When comparing the cardboard, only one line of the shoe last can be compared. The shoe last is three-dimensional (surface structure) no matter which part it is, so it is unscientific to measure or determine a surface with only one line. Whether it is the national standard detection method or the manual detection method, it can only detect one line of the shoe last. The actual shoe last is a three-dimensional surface. It is unscientific and unreliable to control the surface with a line, or to judge the standard degree of the surface.

[0004] Therefore, it is necessary to provide a portable shoe last rear bridge position measurement method to solve the unscientific problem of using a line to measure and determine whether the entire surface of the shoe last rear bridge position is standard in the prior art. Summary of the invention

[0005] In view of this, the present invention proposes a portable shoe last rear bridge position measurement method, aiming to solve the unscientific problem of using a line to measure and determine whether the entire surface of the shoe last rear bridge position is standard in the prior art.

[0006] The present invention provides a portable method for measuring the back bridge position of a shoe last, comprising:

[0007] Collecting the back bridge position information of several shoe lasts with the same heel height but different heels, comparing the back bridge position information of the same heel height, taking the back bridge position information with the highest proportion as the back bridge position information of the mother last corresponding to the heel height, and making the mother last;

[0008] The curved reference surface of the rear body bridge position measuring device is made according to the curved surface of the rear body bottom plate of the mother last, the heel height of the rear body bridge position measuring device is made according to the heel height of the mother last, the rear body length according to the national standard is used as the bottom surface length of the rear body bridge position measuring device, and a plurality of pressure sensors are embedded on the bottom surface of the rear body bridge position measuring device to complete the production of the rear body bridge position measuring device;

[0009] Placing the mother last on the upper part of the rear bridge position measuring device, and collecting standard pressure distribution information through a pressure sensor;

[0010] The rear bridge position measuring device is placed on the bottom of the shoe last to be measured, and the fitting image information of the rear bridge position measuring device and the bottom of the shoe last and the pressure distribution information collected by the pressure sensor are collected. The fitting degree is calculated based on the fitting image information and the pressure distribution information, and the standard degree of the shoe last is obtained based on the fitting degree.

[0011] Furthermore, the collecting of the rear bridge position information of a plurality of shoe lasts with the same heel height but different heels, and comparing the rear bridge position information of the shoe lasts with the same heel height, includes:

[0012] Through 3D scanning technology, the surfaces of the back bridge of several shoe lasts with the same heel height but different heels are converted into the same mesh model, and each mesh node corresponds to a 3D coordinate.

[0013] Construct each shoe last back body bridge position information sequence Hij=(A1, A2, A3, ..., An) according to the three-dimensional coordinates, wherein Hij represents the j-th shoe last back body bridge position information sequence with heel height i, Ak=(Xk, Yk, Zk), Ak represents the k-th three-dimensional coordinate point in Hij, k=1, 2, 3, ..., n; Xk represents the x-axis coordinate of the k-th three-dimensional coordinate point in Hij, Yk represents the y-axis coordinate of the k-th three-dimensional coordinate point in Hij, and Zk represents the z-axis coordinate of the k-th three-dimensional coordinate point in Hij;

[0014] Among them, the parameters in the information sequence of the rear bridge position of each shoe last are recorded in Hij in sequence according to the same direction of the shoe last.

[0015] Furthermore, the method of using the rear bridge position information with the highest proportion as the rear bridge position information of the mother last corresponding to the heel height, and making the mother last, includes:

[0016] A similarity threshold value is set, and a clustering algorithm is used to divide all shoe last rear bridge position information sequences into a number of clusters, wherein the similarity between any two shoe last rear bridge position information sequences in each cluster is greater than or equal to the similarity threshold value;

[0017] Select the cluster with the largest number of information sequences of the bridge position of the back of the shoe last, and calculate the three-dimensional coordinates of each grid node corresponding to the mother last by the following formula:

[0018] Ck=((X1+X2+…+Xq) / q, (Y1+Y2+…+Yq) / q, (Z1+Z2+…+Zq) / q);

[0019] In the above formula, Ck represents the kth three-dimensional coordinate point of the back bridge position information of the mother last, q represents the number of three-dimensional coordinate points in the cluster with the largest number of back bridge position information sequences of the shoe last, Xq represents the X-axis coordinate of the qth three-dimensional coordinate point in the cluster with the largest number of back bridge position information sequences of the shoe last, Yq represents the Y-axis coordinate of the qth three-dimensional coordinate point in the cluster with the largest number of back bridge position information sequences of the shoe last, and Zq represents the Z-axis coordinate of the qth three-dimensional coordinate point in the cluster with the largest number of back bridge position information sequences of the shoe last.

[0020] Furthermore, when the similarity between any two shoe last rear bridge position information sequences in each cluster is greater than or equal to the similarity threshold value, it includes:

[0021] The similarity of the information sequences of any two shoe last back bridge positions in each cluster is calculated by the following formula:

[0022]

[0023] In the above formula, D represents the similarity of the information sequence of any two shoe last back bridge positions in each cluster, (Xb, Yb, Zb) represents one of the three-dimensional coordinate points in the cluster, and (Xc, Yc, Zc) represents another three-dimensional coordinate point in the cluster.

[0024] Furthermore, when the back body length according to the national standard is used as the bottom surface length of the back body bridge position measuring device, it includes:

[0025] The national standard rear body length is 138 mm, and 138 mm is used as the bottom surface length of the rear body bridge position measuring device.

[0026] Furthermore, the step of placing the mother last on the upper part of the rear bridge position measuring device and collecting standard pressure distribution information through a pressure sensor includes:

[0027] Collect pressure information from each pressure sensor, and construct a standard pressure distribution sequence Y=(y1, y2, y3, ..., yp) of the mother last according to the pressure information;

[0028] Wherein, yw represents the pressure information of the w-th pressure sensor, w=1, 2, 3, ..., p.

[0029] Furthermore, the step of placing the rear bridge position measuring device on the bottom of the shoe last to be measured and collecting the fitting image information of the rear bridge position measuring device and the bottom of the shoe last and the pressure distribution information collected by the pressure sensor includes:

[0030] Collect the pressure distribution information of each shoe last to be measured when it is placed on the rear bridge position measuring device, and construct the pressure distribution sequence Ya=(ya1, ya2, ya3, ..., yap) of each shoe last;

[0031] Wherein, Ya represents the pressure distribution sequence of the a-th shoe last, yaw represents the pressure information of the w-th pressure sensor of the a-th shoe last, w=1, 2, 3, ..., p;

[0032] Collecting images of each shoe last to be measured when it is placed on the back bridge position measuring device;

[0033] The edge detection algorithm is used to extract the contours of the shoe last and the back bridge position measuring device in the image;

[0034] According to the edge detection results and threshold segmentation, the image is divided into contact area and gap area, and the area of ​​the gap area is calculated.

[0035] Furthermore, the calculation of the degree of fit according to the fit image information and the pressure distribution information includes:

[0036] The similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the master last is calculated, and the fit is calculated according to the similarity and the area of ​​the gap region; wherein the fit is calculated according to the following formula:

[0037] When the similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the master last is set to 1 and the gap area is 0, the fit is full score, and the full fit score is equal to 100;

[0038] T = α*100+β*100;

[0039] In the above formula, T represents the degree of fit, α represents the influence coefficient of the similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the master last, and β represents the influence coefficient of the gap area, wherein the value ranges of α and β are both 0-0.5.

[0040] Furthermore, the calculating of the similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the master last includes:

[0041]

[0042] In the above formula, S represents the similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the mother last, yaw represents the pressure information of the w-th pressure sensor of the a-th shoe last, yw represents the pressure information of the w-th pressure sensor, w=1, 2, 3, ..., p; p represents the total number of pressure sensors of the rear bridge position measuring device.

[0043] Furthermore, obtaining the standard degree of the shoe last according to the fit degree includes:

[0044] Setting a first fit degree and a second fit degree, wherein the first fit degree is greater than the second fit degree;

[0045] If the fit is equal to 100, the shoe last is of first-class standard;

[0046] If the degree of fit is greater than the first degree of fit and less than 100, the shoe last is of secondary standard;

[0047] If the degree of fit is less than or equal to the first degree of fit, and greater than or equal to the second degree of fit, the shoe last is of the third-level standard;

[0048] If the degree of fit is less than the second degree of fit, the shoe last is of level 4 standard;

[0049] Among them, the standards of shoe lasts are ranked from high to low as level one, level two, level three and level four.

[0050] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention first collects the information of the back bridge position of several shoe lasts with the same heel height but different shoe lasts, and compares and selects the information of the back bridge position with the highest proportion as the standard data of the master last, so as to accurately represent the characteristics of the shoe last with a specific heel height, and ensure that the production of the master last is more in line with actual needs. This method based on big data analysis avoids the limitations of a single model and can reflect the common characteristics of different shoe last designs. Secondly, the design of the back bridge position measuring device is accurate, and it is made based on the back bottom plate curved surface, heel height and national standard back length of the master last, which ensures the high precision and standardization of the measuring instrument and provides a reliable benchmark for subsequent measurements. Furthermore, the integrated pressure sensor can collect the pressure distribution between the shoe last and the measuring device in real time, and calculate the fit degree in combination with the image information, providing a quantitative evaluation index for the shoe last design. This method not only improves the accuracy and efficiency of the measurement, but also better reflects the comfort and adaptability of the shoe last, and provides a scientific basis for footwear design and production. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0052] Figure 1 A flow chart of a portable shoe last rear bridge position measurement method provided by an embodiment of the present invention;

[0053] Figure 2 A schematic diagram of a shoe last provided by an embodiment of the present invention being placed above a rear body bridge position measuring device. DETAILED DESCRIPTION

[0054] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0055] In some embodiments of the present application, see Figure 1 As shown, this embodiment provides a portable method for measuring the bridge position of the back of a shoe last, comprising the following steps:

[0056] S100, collecting the back bridge position information of several shoe lasts with the same heel height but different heels, comparing the back bridge position information of the same heel height, taking the back bridge position information with the highest proportion as the back bridge position information of the mother last corresponding to the heel height, and making the mother last;

[0057] S200, manufacturing a curved reference surface of a rear body bridge position measuring device according to the curved surface of the rear body bottom plate of the mother last, manufacturing the heel height of the rear body bridge position measuring device according to the heel height of the mother last, using the national standard rear body length as the bottom surface length of the rear body bridge position measuring device, embedding a plurality of pressure sensors on the bottom surface of the rear body bridge position measuring device, and completing the manufacturing of the rear body bridge position measuring device;

[0058] S300, placing the mother last on the upper part of the rear bridge position measuring device, and collecting standard pressure distribution information through a pressure sensor;

[0059] S400, placing the back bridge position measuring device on the bottom of the shoe last to be measured, collecting fitting image information of the back bridge position measuring device and the bottom of the shoe last and pressure distribution information collected by the pressure sensor, calculating the fitting degree according to the fitting image information and the pressure distribution information, and obtaining the standard degree of the shoe last according to the fitting degree.

[0060] It can be understood that the present invention first collects the rear bridge position information of several shoe lasts with the same heel height but different heels, and compares and selects the rear bridge position information with the highest proportion as the standard data of the master last, which can accurately represent the characteristics of the shoe last with a specific heel height, ensuring that the production of the master last is more in line with actual needs. This method based on big data analysis avoids the limitations of a single model and can reflect the common characteristics of different shoe last designs. Secondly, the rear bridge position measuring device is precisely designed and is made based on the rear bottom plate curved surface, heel height and national standard rear length of the master last, ensuring the high precision and standardization of the measuring instrument, and providing a reliable benchmark for subsequent measurements. Furthermore, the integrated pressure sensor can collect the pressure distribution between the shoe last and the measuring device in real time, and calculate the fit degree in combination with the image information, providing a quantitative evaluation index for the shoe last design. This method not only improves the accuracy and efficiency of the measurement, but also better reflects the comfort and adaptability of the shoe last, providing a scientific basis for footwear design and production. Specifically, Figure 2 Schematic diagram of the shoe last placed on the rear bridge position measuring device.

[0061] In some embodiments of the present application, when collecting the rear bridge position information of a plurality of shoe lasts with the same heel height but different heels, and comparing the rear bridge position information of the same heel height, the method includes:

[0062] Through 3D scanning technology, the surfaces of the back bridge of several shoe lasts with the same heel height but different heels are converted into the same mesh model, and each mesh node corresponds to a 3D coordinate.

[0063] Construct each shoe last back body bridge position information sequence Hij=(A1, A2, A3, ..., An) according to the three-dimensional coordinates, wherein Hij represents the j-th shoe last back body bridge position information sequence with heel height i, Ak=(Xk, Yk, Zk), Ak represents the k-th three-dimensional coordinate point in Hij, k=1, 2, 3, ..., n; Xk represents the x-axis coordinate of the k-th three-dimensional coordinate point in Hij, Yk represents the y-axis coordinate of the k-th three-dimensional coordinate point in Hij, and Zk represents the z-axis coordinate of the k-th three-dimensional coordinate point in Hij;

[0064] Among them, the parameters in the information sequence of the rear bridge position of each shoe last are recorded in Hij in sequence according to the same direction of the shoe last.

[0065] In some embodiments of the present application, the rear bridge position information with the highest proportion is used as the rear bridge position information of the master last corresponding to the heel height, and when making the master last, the steps include:

[0066] A similarity threshold is set, and a clustering algorithm is used to divide all shoe last rear bridge position information sequences into several clusters, wherein the similarity between any two shoe last rear bridge position information sequences in each cluster is greater than or equal to the similarity threshold;

[0067] Select the cluster with the largest number of information sequences of the bridge position of the back of the shoe last, and calculate the three-dimensional coordinates of each grid node corresponding to the mother last by the following formula:

[0068] Ck=((X1+X2+…+Xq) / q, (Y1+Y2+…+Yq) / q, (Z1+Z2+…+Zq) / q);

[0069] In the above formula, Ck represents the kth three-dimensional coordinate point of the back bridge position information of the mother last, q represents the number of three-dimensional coordinate points in the cluster with the largest number of back bridge position information sequences of the shoe last, Xq represents the X-axis coordinate of the qth three-dimensional coordinate point in the cluster with the largest number of back bridge position information sequences of the shoe last, Yq represents the Y-axis coordinate of the qth three-dimensional coordinate point in the cluster with the largest number of back bridge position information sequences of the shoe last, and Zq represents the Z-axis coordinate of the qth three-dimensional coordinate point in the cluster with the largest number of back bridge position information sequences of the shoe last.

[0070] In some embodiments of the present application, when the similarity between any two shoe last rear bridge position information sequences in each cluster is greater than or equal to the similarity threshold value, it includes:

[0071] The similarity of the information sequences of any two shoe last back bridge positions in each cluster is calculated by the following formula:

[0072]

[0073] In the above formula, D represents the similarity of the information sequence of any two shoe last back bridge positions in each cluster, (Xb, Yb, Zb) represents one of the three-dimensional coordinate points in the cluster, and (Xc, Yc, Zc) represents another three-dimensional coordinate point in the cluster.

[0074] It can be understood that the present invention provides an accurate and scientific method to extract the bridge position information of the back of the shoe last and make the master last by combining three-dimensional scanning technology with clustering algorithm. First, the bridge position of the back of the shoe last is converted into a grid model using three-dimensional scanning technology, and each three-dimensional coordinate point is accurately recorded in an information sequence, which ensures the accuracy and consistency of the data. Secondly, by setting a similarity limit value, a clustering algorithm is used to divide the information sequences of the bridge position of the back of different shoe lasts into multiple clusters, and the cluster with the largest number is selected to determine the bridge position of the back of the master last. By calculating the average value of all three-dimensional coordinates in the cluster, the bridge position data of the back of the master last representing the characteristics of the high heel shoe last can be obtained, thereby ensuring that the master last has good representativeness in a variety of shoe last samples. This process not only avoids the deviation of the traditional manual selection method, but also improves the automation and accuracy of data processing through the algorithm. In addition, the combination of clustering algorithm and similarity calculation makes the selection of rear bridge position information more in line with actual usage needs, effectively improves the efficiency and accuracy of shoe last customization and production, and provides a more scientific basis for the research and development and optimization of footwear products.

[0075] In some embodiments of the present application, when the back body length according to the national standard is used as the bottom surface length of the back body bridge position measuring device, it includes:

[0076] The national standard rear body length is 138mm, and 138mm is used as the bottom length of the rear body bridge position measuring device.

[0077] In some embodiments of the present application, the mother last is placed on the upper part of the rear bridge position measuring device, and the standard pressure distribution information is collected by the pressure sensor, including:

[0078] Collect the pressure information of each pressure sensor, and construct the standard pressure distribution sequence Y=(y1, y2, y3, ..., yp) of the mother last according to the pressure information;

[0079] Wherein, yw represents the pressure information of the w-th pressure sensor, w=1, 2, 3, ..., p.

[0080] In some embodiments of the present application, the back bridge position measuring device is placed on the bottom of the shoe last to be measured, and the fitting image information of the back bridge position measuring device and the bottom of the shoe last and the pressure distribution information collected by the pressure sensor are collected, including:

[0081] Collect the pressure distribution information of each shoe last to be measured when it is placed on the rear bridge position measuring device, and construct the pressure distribution sequence Ya=(ya1, ya2, ya3, ..., yap) of each shoe last;

[0082] Wherein, Ya represents the pressure distribution sequence of the a-th shoe last, yaw represents the pressure information of the w-th pressure sensor of the a-th shoe last, w=1, 2, 3, ..., p;

[0083] Collecting images of each shoe last to be measured when it is placed on the back bridge position measuring device;

[0084] The edge detection algorithm is used to extract the contours of the shoe last and the back bridge position measuring device in the image;

[0085] According to the edge detection results and threshold segmentation, the image is divided into contact area and gap area, and the area of ​​the gap area is calculated.

[0086] In some embodiments of the present application, when calculating the degree of fit according to the fit image information and the pressure distribution information, it includes:

[0087] The similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the master last is calculated, and the fit is calculated according to the similarity and the area of ​​the gap region; wherein the fit is calculated according to the following formula:

[0088] When the similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the master last is set to 1 and the gap area is 0, the fit is full score, and the full fit score is equal to 100;

[0089] T = α*100+β*100;

[0090] In the above formula, T represents the fit, α represents the influence coefficient of the similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the master last, and β represents the influence coefficient of the gap area, where the value ranges of α and β are both 0-0.5.

[0091] In some embodiments of the present application, calculating the similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the master last includes:

[0092]

[0093] In the above formula, S represents the similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the mother last, yaw represents the pressure information of the w-th pressure sensor of the a-th shoe last, yw represents the pressure information of the w-th pressure sensor, w=1, 2, 3, …, p; p represents the total number of pressure sensors of the rear bridge position measuring device.

[0094] It is understandable that this embodiment significantly improves the accuracy and reliability of the measurement of the bridge position of the back body of the shoe last through standardized national back body length, accurate pressure sensor data acquisition and image processing technology. First, 138mm is used as the bottom surface length of the back body bridge position measuring device. This design based on national standards ensures the uniformity and standardization of the measuring device in various shoe last applications, and provides a reliable benchmark for the accurate testing and comparison of footwear products. Secondly, the pressure sensor is used to collect the pressure distribution information between the shoe last and the measuring device in real time. By constructing a pressure distribution sequence, the fit between the shoe last and the mother last can be quantified, providing a scientific basis for the comfort and adaptability of the shoe last design. Combined with the edge detection algorithm for image processing, the contact area and the gap area can be accurately divided, and the fit state between the bottom of the shoe last and the measuring device can be further analyzed, so as to carefully evaluate the overall design of the shoe last. By calculating the similarity of the pressure distribution sequence and the area of ​​the gap area, the fit score is comprehensively obtained, which effectively improves the comprehensiveness and accuracy of the measurement. This method can not only quantify the fit between the shoe last and the master last, but also reduce human errors and improve production efficiency through standardized and automated measurement processes. It also provides important support for the customization and optimized design of footwear products, helping to improve the quality and competitiveness of footwear products on the market.

[0095] In some embodiments of the present application, obtaining the standard degree of the shoe last according to the fit degree includes:

[0096] Setting a first fit degree and a second fit degree, wherein the first fit degree is greater than the second fit degree;

[0097] If the fit is equal to 100, the shoe last is of first-class standard;

[0098] If the fit is greater than the first fit and less than 100, the shoe last is of the second-level standard;

[0099] If the fit is less than or equal to the first fit, and greater than or equal to the second fit, the shoe last is of the third-level standard;

[0100] If the fit is less than the second fit, the shoe last is of the fourth level standard;

[0101] Among them, the standards of shoe lasts are ranked from high to low as level one, level two, level three and level four.

[0102] It can be understood that the present invention divides shoe lasts into four levels based on different ranges of fit: primary standard, secondary standard, tertiary standard and quaternary standard, which can accurately reflect the degree of matching between shoe lasts and mother lasts. The primary standard indicates perfect fit, with a fit of 100, ensuring that the shoe last has optimal comfort and adaptability. As the fit decreases, the standard grade of the shoe last gradually decreases, which allows producers to grade shoe lasts according to different needs, thereby improving the precision and adaptability of production. By introducing the settings of the first fit and the second fit, it is possible to respond to different fit levels more flexibly, accurately divide the quality levels of shoe lasts, and facilitate product screening, optimization and customization, thereby improving the standardized management of footwear products.

[0103] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0104] The present application is described with reference to flowcharts and / or block diagrams of methods, devices (systems) and computer program products according to embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0105] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0106] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0107] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A portable method for measuring the bridge position of the back of a shoe last, characterized in that: include: Collecting the back bridge position information of several shoe lasts with the same heel height but different heels, comparing the back bridge position information of the same heel height, taking the back bridge position information with the highest proportion as the back bridge position information of the mother last corresponding to the heel height, and making the mother last; The curved reference surface of the rear body bridge position measuring device is made according to the curved surface of the rear body bottom plate of the mother last, the heel height of the rear body bridge position measuring device is made according to the heel height of the mother last, the rear body length according to the national standard is used as the bottom surface length of the rear body bridge position measuring device, and a plurality of pressure sensors are embedded on the bottom surface of the rear body bridge position measuring device to complete the production of the rear body bridge position measuring device; Placing the mother last on the upper part of the rear bridge position measuring device, and collecting standard pressure distribution information through a pressure sensor; The rear bridge position measuring device is placed on the bottom of the shoe last to be measured, and the fitting image information of the rear bridge position measuring device and the bottom of the shoe last and the pressure distribution information collected by the pressure sensor are collected. The fitting degree is calculated based on the fitting image information and the pressure distribution information, and the standard degree of the shoe last is obtained based on the fitting degree.

2. The portable shoe last rear bridge position measurement method according to claim 1, characterized in that: The collecting of the back bridge position information of a plurality of shoe lasts with the same heel height but different heels, and comparing the back bridge position information of the shoe lasts with the same heel height, comprises: Through 3D scanning technology, the surfaces of the back bridge of several shoe lasts with the same heel height but different heels are converted into the same mesh model, and each mesh node corresponds to a 3D coordinate. Construct each shoe last back body bridge position information sequence Hij=(A1, A2, A3, ..., An) according to the three-dimensional coordinates, wherein Hij represents the j-th shoe last back body bridge position information sequence with heel height i, Ak=(Xk, Yk, Zk), Ak represents the k-th three-dimensional coordinate point in Hij, k=1, 2, 3, ..., n; Xk represents the x-axis coordinate of the k-th three-dimensional coordinate point in Hij, Yk represents the y-axis coordinate of the k-th three-dimensional coordinate point in Hij, and Zk represents the z-axis coordinate of the k-th three-dimensional coordinate point in Hij; Among them, the parameters in the information sequence of the rear bridge position of each shoe last are recorded in Hij in sequence according to the same direction of the shoe last.

3. The portable shoe last rear bridge position measurement method according to claim 2, characterized in that: The method of using the rear bridge position information with the highest proportion as the rear bridge position information of the master last corresponding to the heel height, and making the master last, includes: A similarity threshold value is set, and a clustering algorithm is used to divide all shoe last rear bridge position information sequences into a number of clusters, wherein the similarity between any two shoe last rear bridge position information sequences in each cluster is greater than or equal to the similarity threshold value; Select the cluster with the largest number of information sequences of the bridge position of the back of the shoe last, and calculate the three-dimensional coordinates of each grid node corresponding to the mother last by the following formula: Ck=((X1+X2+…+Xq) / q, (Y1+Y2+…+Yq) / q, (Z1+Z2+…+Zq) / q); In the above formula, Ck represents the kth three-dimensional coordinate point of the back bridge position information of the mother last, q represents the number of three-dimensional coordinate points in the cluster with the largest number of back bridge position information sequences of the shoe last, Xq represents the X-axis coordinate of the qth three-dimensional coordinate point in the cluster with the largest number of back bridge position information sequences of the shoe last, Yq represents the Y-axis coordinate of the qth three-dimensional coordinate point in the cluster with the largest number of back bridge position information sequences of the shoe last, and Zq represents the Z-axis coordinate of the qth three-dimensional coordinate point in the cluster with the largest number of back bridge position information sequences of the shoe last.

4. The portable shoe last rear bridge position measurement method according to claim 3, characterized in that: When the similarity of any two shoe last rear bridge position information sequences in each cluster is greater than or equal to the similarity threshold value, it includes: The similarity of the information sequences of any two shoe last back bridge positions in each cluster is calculated by the following formula: In the above formula, D represents the similarity of the information sequence of any two shoe last back bridge positions in each cluster, (Xb, Yb, Zb) represents one of the three-dimensional coordinate points in the cluster, and (Xc, Yc, Zc) represents another three-dimensional coordinate point in the cluster.

5. The portable shoe last rear bridge position measurement method according to claim 4, characterized in that: When the rear body length according to the national standard is used as the bottom surface length of the rear body bridge position measuring device, it includes: The national standard rear body length is 138 mm, and 138 mm is used as the bottom surface length of the rear body bridge position measuring device.

6. The portable shoe last rear bridge position measurement method according to claim 5, characterized in that: The method of placing the mother last on the upper part of the rear body bridge position measuring device and collecting standard pressure distribution information through the pressure sensor includes: Collect pressure information from each pressure sensor, and construct a standard pressure distribution sequence Y=(y1, y2, y3, ..., yp) of the mother last according to the pressure information; Wherein, yw represents the pressure information of the w-th pressure sensor, w=1, 2, 3, ..., p.

7. The portable shoe last rear bridge position measurement method according to claim 6, characterized in that: Placing the rear bridge position measuring device on the bottom of the shoe last to be measured, and collecting the fitting image information of the rear bridge position measuring device and the bottom of the shoe last and the pressure distribution information collected by the pressure sensor, comprises: Collect the pressure distribution information of each shoe last to be measured when it is placed on the rear bridge position measuring device, and construct the pressure distribution sequence Ya=(ya1, ya2, ya3, ..., yap) of each shoe last; Wherein, Ya represents the pressure distribution sequence of the a-th shoe last, yaw represents the pressure information of the w-th pressure sensor of the a-th shoe last, w=1, 2, 3, ..., p; Collecting images of each shoe last to be measured when it is placed on the back bridge position measuring device; The edge detection algorithm is used to extract the contours of the shoe last and the back bridge position measuring device in the image; According to the edge detection results and threshold segmentation, the image is divided into contact area and gap area, and the area of ​​the gap area is calculated.

8. The portable shoe last rear bridge position measurement method according to claim 7, characterized in that: The calculating of the degree of fit according to the fit image information and the pressure distribution information includes: The similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the master last is calculated, and the fit is calculated according to the similarity and the area of ​​the gap region; wherein the fit is calculated according to the following formula: When the similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the master last is set to 1 and the gap area is 0, the fit is full score, and the full fit score is equal to 100; T＝α*100+β*100； In the above formula, T represents the degree of fit, α represents the influence coefficient of the similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the master last, and β represents the influence coefficient of the gap area, wherein the value ranges of α and β are both 0-0.

5.

9. The portable shoe last rear bridge position measurement method according to claim 8, characterized in that: The calculating of the similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the master last comprises: In the above formula, S represents the similarity between the pressure distribution sequence of the shoe last and the standard pressure distribution sequence of the mother last, yaw represents the pressure information of the w-th pressure sensor of the a-th shoe last, yw represents the pressure information of the w-th pressure sensor, w=1, 2, 3, ..., p; p represents the total number of pressure sensors of the rear bridge position measuring device.

10. The portable shoe last rear bridge position measurement method according to claim 8, characterized in that: The step of obtaining the standard degree of the shoe last according to the fit degree includes: Setting a first fit degree and a second fit degree, wherein the first fit degree is greater than the second fit degree; If the fit is equal to 100, the shoe last is of first-class standard; If the degree of fit is greater than the first degree of fit and less than 100, the shoe last is of secondary standard; If the degree of fit is less than or equal to the first degree of fit, and greater than or equal to the second degree of fit, the shoe last is of the third-level standard; If the degree of fit is less than the second degree of fit, the shoe last is of level 4 standard; Among them, the standards of shoe lasts are ranked from high to low as level one, level two, level three and level four.

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