WO2017025779A1

WO2017025779A1 - Method for selecting a shoe by comparing the measurements of a foot with the measurements of shoe lasts

Info

Publication number: WO2017025779A1
Application number: PCT/IB2015/056174
Authority: WO
Inventors: Giorgio Raccanelli
Original assignee: Trya S.R.L.
Priority date: 2015-08-13
Filing date: 2015-08-13
Publication date: 2017-02-16

Abstract

The present invention relates to a method for selecting a shoe wherein, by means of a computer, the measurements of a foot are compared with a plurality of comparison elements, wherein the measurements of the foot are linear measurements and wherein the comparison element is a shoe last and each comparison element is associated with a different shoe; for each comparison between the measurements of the foot and the plurality of shoe lasts a parameter of the distance between the linear measurements of the foot and the corresponding linear measurements of the shoe last is calculated and a shoe associated with the comparison element is selected as a function of the calculated distance parameters.

Description

METHOD FOR SELECTING A SHOE BY COMPARING THE MEASUREMENTS OF A FOOT WITH THE MEASUREMENTS OF SHOE LASTS"

DESCRIPTION

TECHNICAL FIELD

The present invention relates to the footwear industry and in particular to computerized methods for comparing a foot with a shoe.

More particularly, the invention relates to a method for selecting a shoe according to the preamble of claim 1.

PRIOR ART

Nowadays the production of footwear is generally implemented as mass production. Buyers must therefore try different styles of shoes to find those preferable to them, not only from an aesthetic point of view, but also, and above all, to find shoes that are comfortable. It is a well-known fact that wearing shoes that do not fit perfectly to the shape of the feet can lead to significant discomfort, such as posture problems, pain and abrasion.

To solve these problems, it is possible have footwear made to measure.

The making of made-to-measure footwear requires a preliminary step of measuring some parameters of the user's foot (such as, for example, the length, the circumference at the ball of the foot, the circumference at the arch and others), on the basis of which a model is made, called a "last", on the basis of which the sole, the upper and the other parts of the shoe are shaped.

Recently, with the ever increasing sophistication of scanning techniques and graphic modelling software, various automated methods for measuring the foot have been developed, for example methods that make use of laser scanning techniques or which derive the measurements of the foot from photographic images of the same. These techniques permit the realization of made-to-measure shoes without the user having to necessarily go to the shoemaker to have his foot measured.

The process of making made-to-measure shoes is, however, still long and laborious, which makes such shoes expensive; for this reason, some computer software l programs have been developed that permit the user to select, from among those available, shoes that best fit his or her foot.

For example, U.S. patent application number US2011055053A makes known the comparison of a three-dimensional scan of the internal volume of a shoe with a three- dimensional scan of the foot to obtain the " best fit" between the shoe and the foot, i.e. to find the footwear that best suits the shape of the foot in question. This solution, however, is not optimal, since the scanning of the internal volume of the shoe does not take account of the fact that the soft parts of the footwear itself deform when the foot enters it. Furthermore, since the comparison algorithms make use of three- dimensional reconstructions, which in practice are saved in files of large dimensions, these require a high computational effort from the computers that have to run the programs, which greatly limits its application.

For example, algorithms of the type described in US2011055053A could not be used in the selection of shoes online, for example on websites like Zalando® or Amazon®, unless considerable investments in computer networks are made.

There is therefore a need for computerized methods that allow automatic and efficient selection of the shoe(s) that best adapt(s) to the shape of a foot.

PURPOSE AND SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the drawbacks of the prior art. In particular it is an aim of the present invention to present a method which in a simple way allows a reduction of the computational resources of a computer necessary to make a comparison between the shape of a foot and a shoe.

It is also an aim of the present invention to present a computerized method that allows a more accurate selection of the shoe that best fits a foot.

These and other aims of the present invention are achieved by a method incorporating the features of the attached claims, which form an integral part of this description.

The idea underlying the present invention envisages a computerized comparison of the foot with the "lasts" of the shoes among which the one(s) which is/ are best suited to the foot must be selected. The foot and the "lasts" are treated by the computer as points of a M-dimensional space; the foot and the "lasts", therefore, are vectors whose M elements are linear measurements of the foot taken according to predefined curves and lines, such as the circumference of the arch of the foot, the length of the foot, etc. The selection of the optimal shoe is made by comparing the foot vector with vectors of the available shoe lasts. This comparison results, therefore, in a comparison between the individual elements of the vectors, and, therefore, between linear measurements that a computer can easily handle without great computational effort. Furthermore, compared to methods such as that known from US2011055053, the comparison between the foot and the "lasts" of the shoes improves the accuracy of the selection since the "last" is an element that takes into account the deformations of the structure and the materials from which the shoe is made that occur when worn by the foot.

In one embodiment, the method provides for the addition to the measurements of the foot (or equivalently the subtraction from the measurements of the last) of the tolerance values that take into account the fact that the shoe which best suits the foot is not necessarily the one that has the "last" with identical measurements to that of the foot, but the "last" related to the shoe in which the foot can be best fitted. These tolerances preferably vary from shoe to shoe, or model to model, and represent the know-how of the shoemaker.

The present invention also includes a computer program containing portions of code which, when executed, allow the realization of a method for the selection of shoes as described below and/ or claimed.

Further advantageous features of the present invention will become apparent from the following description and attached claims, which form an integral part of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described hereinafter with reference to non-limiting examples, provided by way of explanatory and non-limiting example in the attached drawings. These drawings illustrate different aspects and embodiments of the present invention and, where appropriate, reference numerals showing like structures, components, materials and/ or elements in different figures are denoted by like reference numerals. Figure 1 illustrates a flow diagram of the method according to one embodiment of the invention.

Figure 2 shows a block diagram of a system that implements the method of Figure 1. Figure 3 illustrates an electronic file containing the data of a foot used in the method of Figure 1.

Figure 4 illustrates a table containing data of shoe lasts.

Figure 5 shows the linear measurements of the foot that can be used in the method of Figure 1.

DETAILED DESCRIPTION OF THE INVENTION

While the invention is susceptible to various modifications and alternative constructions, some embodiments, supplied for non-limiting explanatory purposes only, are described below in detail.

It should be understood, however, that there is no intention to limit the invention to the specific illustrated embodiments, but, on the contrary, the invention intends to cover all modifications, alternative constructions, and equivalents that fall within the scope of the invention as defined in the claims.

In the following description, therefore, the use of "for example", "etc.", "or" indicates non-exclusive alternatives without any limitations, unless otherwise indicated; the use of "also" means "including, but not limited to" unless otherwise indicated; the use of "includes/comprises" means "includes/comprises, but not limited to" unless otherwise indicated.

The term "shoe last" or "Last" refers to an object, physical or electronic, used in the footwear industry in the production process of shoes, whose shapes and dimensions are associated with the internal volume of a shoe.

With reference to Figure 1, a method is described to select shoes in an electronic manner or by means of an appropriate computer program, such as a computer program whose code is stored in an area of a computer.

Solely for illustrative purposes, the method is hereinafter described with reference to a computer network 10, for example the Internet or a local network, illustrated in Figure 2, in which a number of client computers 2 communicate with a server computer 1 . The method starts at step 100 when the server 1 receives a data packet containing the linear measurements of a foot of a person, such as one or more of the following measurements, illustrated in Figure 5: the height from the sole in correspondence with the metatarsals (51), the height of the arch from the sole (52), the heel (53), the ankle (54), the distance between the heel and the ankle (55), the length of the foot (56) and the maximum width of the foot (57).

The linear measurements of the foot can be entered manually by a user of a client computer 2 via a user interface, or can be received by an electronic device connected to the client computer 2 or directly to the server, for example the measurements may be transmitted from a laser scanner. Alternatively, in one embodiment, the client computer 2 or the server 1 may be provided with appropriate computer programs that derive the linear measurements of the foot from 2D or 3D image files. For example, the server 1 may receive from the client 2 photographs of the foot and, in a manner known per se, to derive therefrom the measurements needed.

In one embodiment, the linear measurements of the foot are inserted in a data packet (transported in one or more files) containing M linear measurements p(i).. p(u), with M being a positive integer. The foot is therefore a vector P of an M-dimensional space which, electronically, can be represented as a data packet 300, shown in Figure 3, with a header 30 and a payload 40, in which the payload contains the linear measurements of the foot ₍₁₎ ... _(M).

Once in possession of the linear measurements of the foot, the server 1 proceeds to compare (step 110) the linear measurements of the foot with data relating to a plurality of shoe lasts.

For example, the server 1 compares the linear measurements of the foot with corresponding linear measurements of a plurality of shoe lasts, so as to select (step 120), a shoe as a function of this comparison.

In one embodiment, in addition or alternative to the direct comparison between the linear measurements of the foot and the Last, the server calculates one or more relationships between the linear measurements of the foot to classify the foot itself and select one or more shoes using these classification criteria, for example: - the ratio between the measurements of the length (56) and the maximum width (57) of the foot permits classification of the foot as being "wide-soled" (e.g. if the ratio is less than a given predetermined value, which can vary from footwear manufacturer to footwear manufacturer) or "narrow-soled" (e.g. if the ratio is higher than this set value);

- the ratio between the heel (53) and the length (56) of the foot permits classification of the foot as having a "high arch" (e.g. if the ratio is greater than a given predetermined value, which can vary from footwear manufacturer to footwear manufacturer) or a "low arch" (e.g. if the ratio is less than the predetermined value);

The selection of the Lasts can take place by using also the classification information for the foot which, as stated above, traduces into a value of a ratio between linear measurements of the Last that are greater or smaller than a specific predetermined value. The server 1, therefore, will select the shoe lasts suited to the type of foot, for example, there will be shoe lasts suitable for "narrow-soled" feet and others suitable for "wide-soled" feet and the server will select those suitable according to the ratios calculated and the classification of the foot obtained.

The linear measurements of the Lasts, as well as their classification with respect to the types of foot classified (e.g. wide- or narrow-soled), are preferably known and stored in memory areas accessible to the server 1, in the example of Figure 2, the data of the Lasts are stored in a database 4 connected to the network 10, but other solutions can be foreseen, for example with the Lasts' data stored within the server 1, or on a portable hard drive connected to the server itself.

With reference to the example in Figure 2, the database 4 contains a table, illustrated in Figure 4, wherein each of the FI-FN records contains M linear measurements fid) - fi(M) of the Lasts.

The M linear measurements of the Lasts correspond to the M linear measurements of the foot ₍₁₎ ... _(M) in such a way as to allow a comparison. For example, the first column of the table in Figure 4 contains the measurement of the arch of the foot corresponding to the measurement contained in the packet 300 in Figure 3, the second column of the table in Figure 4 contains the measurement fi{2) of the length of the foot corresponding to the measurement p₍₂₎ contained in the packet 300 in Figure 3, etc... in this way, each Last corresponds to a vector of the M- dimensional space to which the foot vector P belongs and it is possible to make a comparison between the two vectors in a simple way, as shown below.

The comparison between the Lasts Fi and the foot P, indicated with reference No. 110 in Figure 1, is designed to calculate the distance between the foot vector P and the Lasts Fi. This comparison can then be conducted in various modes, hereafter we will describe one of these modes without in any way wishing to limit the invention.

The method foresees setting to zero a counter k (step 111) which will serve to control the algorithm and understand when to end the comparisons.

The method then foresees incrementing the counter k by one (k=k+l), step 112, and calculating (step 113) the difference vector dk as the difference between the Last vector Fk and the foot vector P:

d„ = F„ - P =

The calculation of the difference vector, computationally, results in the calculation of the difference between the single components of the vectors Fk and P, i.e. by carrying out a comparison between the linear measurements of the foot P and those of the Last F_k.

The method then foresees (step 114) a verification that each of the components of the vector dk is greater than or equal to zero. In the event that at least one of the components is less than zero, the method excludes (step 115) the shoe last F from those selectable for the foot. In this case, therefore, the method verifies (step 116) whether the counter k has reached the value N (that is, if all of the Lasts have been compared with the foot) and, if this is not the case, repeats the steps by returning to step 112, where the counter is incremented and a new Last is compared with the foot. In the case in which all the components of dk are greater than or equal to zero, then the method foresees (step 117) the calculation of a relative distance parameter Dr.

Once Dk has been calculated a verification that all of the Lasts have been compared with the foot is made (step 116 described above) and if this is not the case the method returns to step 111 to compare a new shape with the foot.

When all the Lasts Fi have been compared with the foot P (that is, when k=N), the method then foresees (step 120) the selection of the shoe associated with the shoe last, according to the calculated distance parameters D_k. For example, the server 1 extracts the minimum parameter of the calculated parameters D_k and selects the shoe associated with the shoe last related to the minimum distance parameter.

From the description above it is clear how the method described permits the achievement of the proposed aims.

It is therefore clear to a person skilled in the art, that it is possible to make changes and variants to the solution described with reference to the Figures indicated above without thereby departing from the scope of the present patent as defined by the attached claims.

For example, the distance between the foot and the Lasts can be calculated according to criteria other than those described above.

The selection of the shoe is not necessarily bound to the minimum distance parameter, but may depend on other factors, for example, it is possible to decide to select a predetermined number of shoes or to exclude shoes whose Last is too close to the measurements of the foot, i.e. those shoes with a Dk lower than a predetermined value.

In an alternative embodiment to that of Figure 1, the method foresees the modification of the linear measurements p_m of the foot P before performing the comparison between the foot vector and each Last F_t, step 110 of the method.

In particular, to each linear foot measurement p_m, a corresponding value t_i(rn) is added, which value represents a tolerance of fit related to each shoe last j. The tolerance may be higher or lower depending on the type of Last, for example "pointed" shoes may present a considerable tolerance on the length measurement. This produces n foot vectors P^*:

-

Pi 2)> Vi(... ), Vi(M))

where p^* _Q) = p_(j) + t_iQ) with j=l..m.

The method then calculates n difference vectors d_k ^*, in accordance with the number of shoe lasts, as the difference between corresponding foot vectors P^* and Last vectors Ff. fk(i) - (P(i) + tfc(i)) /fc(l) - (P_fc(i))

fk(...) - (P(...) + £/£(...)) /fc(...) - ( P_fe(2))

fk(m) ^~ (P(m) + tfcOn)) fk(m) - ( P_fe(m))

Also in this case, therefore, each difference vector d_k ^* is composed of m components and the method verifies that each of the components thus calculated is greater than or equal to zero. In the event that at least one of the components is less than zero, the method excludes the shoe last F from those for which it is possible to select the optimal shoe for the foot P.

Similarly to the example in Figure 1, the method foresees calculating the distance parameters D_k for those forms whose difference vector has components which are all greater than or equal to zero:

where each of the distance parameters D_k is related to the shoe last with which the comparison was carried out.

Subsequently, then, the shoe associated with the shoe last is selected according to the distance parameters D_k ^* thus calculated.

While in the above examples the distance parameter was calculated from the linear measurements of a foot and the corresponding linear measurements of one shoe last, it is clear that, as stated above, the distance parameter can also be calculated as a distance between a ratio between two linear measurements of the foot (e.g. the ratio between the length and the width of the foot to classify it as a wide-soled or a narrow-soled foot) and a corresponding ratio between two linear measurements of one shoe last.

Claims

1. Method for selecting a shoe, comprising the steps of

- obtaining electronic data of a foot

- comparing the electronic data of a foot with comparative electronic data associated to a plurality of shoes,

- selecting a shoe as a function of the comparison,

characterized by the fact that

the electronic data of a foot include linear measurements of the foot, and the comparative electronic data include linear measurements of a plurality of shoe lasts, and by the fact that the comparison between the electronic data of a foot and the comparative electronic data includes the step of computing, for each shoe last of said plurality, a distance parameter between the linear measurements of the foot and the corresponding linear measurements of the shoe last , and

by the fact that the shoe is selected according to the calculated distance parameters.

2. Method according to claim 1, wherein the shoe associated with the shoe last which has the smallest distance parameter among the calculated distance parameters is selected.

3. Method according to claim 1 or 2, wherein the electronic data of a foot include linear measurements of the foot increased or reduced by a tolerance measure.

4. Method according to claim 3, wherein the tolerance measure depends on the shoe last.

5. Method according to claim 4, wherein for each shoe last the tolerance measure to be added to one or more linear measurements of the foot is selected from a database of tolerances.

6. Method according to any one of the preceding claims, further comprising the step of calculating a difference vector d_k, for each comparison between the measurements of the foot and the plurality of shoe lasts, according to the following relationship: d_k = F_i - P =

wherein F_t represents a vector of a shoe last of said plurality, the components f_{k M}) of said vector being linear measurements of the shoe last Fi, P represents a foot vector whose components are the linear measurements _M) of the foot,

and further comprising the step of verifying that each of the components of the difference vector dk is greater than or equal to zero, so as to calculate the distance parameter only for those shoe lasts in which the distance vector has all components greater than zero.

7. Method according to claim 6, wherein the distance parameter is calculated accordin to the following relationship:

wherein f_k^ represents the single components of the shoe last vector, _(M) represents the single components of the foot vector.

8. Method according to any one of the preceding claims, wherein the linear measurements of the foot are linear measurements included in the list comprising the height from the sole in correspondence with the metatarsals, the height of the arch from the sole, the heel, the ankle, the distance between the heel and the ankle, the length of the foot.

9. Method according to any one of the preceding claims, wherein the linear measurements of the foot are derived from one or more images or photographs of the foot.

10. Method according to any one of the preceding claims, in which the distance parameter is calculated as the distance between a ratio between two linear measurements of the foot and a corresponding ratio between two linear measurements of one shoe last.

11. A computer program comprising portions of code which, when executed on a computer, implement the method according to any one of claims 1 to 10.