FOOT SHAPE MEASUREMENT SYSTEM AND FOOT SHAPE MEASUREMENT METHOD

A foot shape measurement system includes an input reception unit configured to receive an input of 3D data representing a three-dimensional shape of a foot, and a feature parameter calculation unit configured to calculate a feature parameter of the foot based on the 3D data. The feature parameter calculation unit includes a distance calculation unit that calculates, for a rear portion of the foot viewed from a lateral direction, a distance between a protrusion point that protrudes most within a heel range and a retraction point that retracts most within an Achilles tendon range in a foot length direction.

TECHNICAL FIELD

The present disclosure relates to a foot shape measurement system and a foot shape measurement method, and more particularly to a foot shape measurement system and a foot shape measurement method capable of calculating an index for selecting a ready-made shoe.

BACKGROUND ART

A technique for selecting a ready-made shoe that matches a three-dimensional shape of a foot using 3D data obtained by measuring the three-dimensional shape of the foot is known (see, for example, Patent Literature 1).

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Technical Problem

FIG.7is a schematic view of a foot6.FIG.8is a schematic view of a shoe8. When a shape of a heel upper portion7above a most protruding portion6aof a rear portion of the foot6illustrated inFIG.7and a shape of a heel portion9of the shoe8illustrated inFIG.8correspond well to each other, the heel upper portion7of the foot6is caught by the heel portion9of the shoe8when walking while wearing the shoe8, and the shoe8is not removed. When the shape of the heel upper portion7of the foot6and the shape of the heel portion9of the shoe8do not correspond well each other, the rear portion of the foot6rises when walking, and the shoe8is easily removed.

When ready-made shoes having different shapes of the heel portion9of the shoe8corresponding to the difference in the shape of the heel upper portion7of the foot6are manufactured, it is possible to select a ready-made shoe that matches the shape of the heel upper portion7of the foot6.

However, with respect to a size of a ready-made shoe, a foot length, a foot circumference, a foot width, and the like are defined in the JIS standard and the like, but a shape of a rear portion of the foot6is not defined. Therefore, it is difficult to select a ready-made shoe that matches the shape of the rear portion of the foot6.

The present disclosure describes a foot shape measurement system and a foot shape measurement method that facilitate selection of a ready-made shoe that matches the shape of the rear portion of the foot.

Solution to Problem

In order to solve the above problem, the present disclosure provides a foot shape measurement system configured as follows.

A foot shape measurement system includes (a) an input reception unit configured to receive an input of 3D data representing a three-dimensional shape of a foot, and (b) a feature parameter calculation unit configured to calculate a feature parameter of the foot based on the 3D data. The feature parameter calculation unit includes (i) a distance calculation unit configured to calculate, for a rear portion of the foot viewed from a lateral direction, a distance between a protrusion point that protrudes most within a heel range and a retraction point that retracts most within an Achilles tendon range in a foot length direction.

According to the above configuration, the distance calculated by the distance calculation unit can be used as an index for selecting a ready-made shoe. By arranging ready-made shoes according to the distance, it is easy to select a ready-made shoe that matches the shape of the rear portion of the foot.

Preferably, the feature parameter calculation unit further includes (ii) a foot length calculation unit configured to calculate a foot length of the foot, and (iii) a heel index calculation unit configured to calculate a heel index that is a ratio of the distance to the foot length.

In this case, the heel index calculated by the heel index calculation unit can be used as an index for selecting a ready-made shoe. By arranging ready-made shoes according to the heel index, it is easy to select a ready-made shoe that matches a shape of a rear portion of the foot. When a ready-made shoe is designed so that, even when a foot length is different, when a heel index is the same, a shape of a heel portion of the shoe is the same, it is easy to manufacture and select a ready-made shoe.

Preferably, the feature parameter calculation unit further includes (iv) a classification determination unit configured to determine a classification to which the heel index belongs.

In this case, the classification to which the heel index belongs can be used as an index for selecting a ready-made shoe. By arranging ready-made shoes having different shapes of the heel portion for each classification to which the heel index belongs, it is easy to manufacture and select a ready-made shoe.

Preferably, the distance calculation unit calculates the heel range and the Achilles tendon range based on the foot length, and calculates the distance between the protrusion point that protrudes most within the calculated heel range and the retraction point that retracts most within the calculated Achilles tendon range.

In this case, the heel range and the Achilles tendon range can be appropriately set according to the foot length.

The foot shape measurement system further includes (c) a measurement unit configured to measure a three-dimensional shape of the foot, and (d) a 3D data generation unit configured to generate 3D data representing the three-dimensional shape of the foot based on the data measured by the measurement unit. The input reception unit receives an input of the 3D data generated by the 3D data generation unit.

In this case, a function of calculating an index related to the shape of the rear portion of the foot can be incorporated in a foot measurement system that measures the three-dimensional shape of the foot and calculates a representative index such as a foot length and a foot circumference.

Further, in order to solve the above problems, the present disclosure provides a foot shape measurement method configured as follows.

A foot shape measurement method for acquiring a shape feature of a foot, the foot shape measurement method including (i) a protrusion point specifying step of specifying a protrusion point that protrudes most within a heel range for a rear portion of the foot viewed from a lateral direction, (ii) a retraction point specifying step of specifying a retraction point that retracts most within an Achilles tendon range for the rear portion of the foot viewed from the lateral direction, and (iii) a distance measuring step of measuring a distance between the protrusion point and the retraction point in a foot length direction.

According to the above method, by arranging ready-made shoes according to the distance measured in the distance measuring step, it is easy to select a ready-made shoe that matches the shape of the rear portion of the foot.

Preferably, the foot shape measurement method further includes (iv) a foot length calculating step of calculating a foot length of the foot, and (v) a heel index calculating step of calculating a heel index that is a ratio of the distance to the foot length.

In this case, the classification to which the heel index belongs can be used as an index for selecting a ready-made shoe. By arranging ready-made shoes having different shapes of the heel portion for each classification to which the heel index belongs, it is easy to manufacture and select a ready-made shoe.

Advantageous Effects of Invention

According to the present disclosure, it is possible to calculate a feature parameter related to a shape of a rear portion of a foot. By arranging ready-made shoes using the feature parameter related to the shape of the rear portion of the foot as an index, it is easy to select a ready-made shoe that matches the shape of the rear portion of the foot.

DESCRIPTION OF EMBODIMENTS

Hereinafter, a foot shape measurement system and a foot shape measurement method of the present disclosure will be described with reference to the drawings.

<First Embodiment> A foot shape measurement system10according to the first embodiment will be described with reference toFIGS.1to4. The foot shape measurement system10executes a foot shape measurement method that is a measurement method for acquiring a shape feature of a foot.

FIG.1is a block diagram illustrating an overall configuration of the foot shape measurement system10. As illustrated inFIG.1, the foot shape measurement system10includes a measurement unit12, a terminal16, and a data processing unit20. The measurement unit12and the terminal16are coupled to the data processing unit20directly or via a communication network such as the Internet. For example, the data processing unit20is configured using one or a plurality of servers. For example, the data processing unit20is configured as a computer device including a processor such as a CPU, a memory such as a ROM and a RAM, a storage, a communication device, and the like. For example, the terminal16is a smartphone, a tablet terminal, a personal computer, or the like. The data processing unit20and the terminal16may be configured using one common personal computer.

The measurement unit12measures a three-dimensional shape of a foot6. For example, the measurement unit12is configured to measure a shape of the foot6placed on a transparent plate14by a light cutting method. Data13measured by the measurement unit12is transmitted to the data processing unit20.

The data processing unit20includes a 3D data generation unit22, an input reception unit24, a feature parameter calculation unit26, a communication unit28, and a data storage unit21.

The 3D data generation unit22generates 3D data23representing the three-dimensional shape of the foot6based on the data13transmitted from the measurement unit12to the data processing unit20.

The input reception unit24receives an input of the 3D data23generated by the 3D data generation unit22, and sends 3D data25having received the input to the feature parameter calculation unit26and the communication unit28.

The feature parameter calculation unit26calculates various feature parameters27of the foot6based on the 3D data25sent from the input reception unit24, and transmits the feature parameters to the communication unit28.

The communication unit28receives data17from the terminal16and transmits data29to the terminal16. For example, based on the data17transmitted in response to the operation on the terminal16, the communication unit28generates the data29for displaying a three-dimensional image of the 3D data25sent from the input reception unit24, the feature parameter27sent from the feature parameter calculation unit26, or the like on the screen of the terminal16or outputting the same to a printer (not illustrated) coupled to the terminal16. The communication unit28transmits the generated data29to the terminal16.

The data storage unit21appropriately stores the 3D data23generated by the 3D data generation unit22, the feature parameter27calculated by the feature parameter calculation unit26, and the like as necessary.

The feature parameter related to the shape of the rear portion of the foot6will be described with reference toFIGS.3(a) and3(b).FIG.3(a)is a schematic view of the foot6of which a sole6cis in contact with a plane4as viewed from a lateral direction (left-right direction of the foot6).FIG.3(b)is a schematic view of the foot6viewed from above the plane4.

As illustrated inFIGS.3(a) and3(b), a direction of a center line6xof the foot passing through a second toe end6aof the foot6is defined as a first direction1(front-rear direction1), and a distance from a heel rear end of the foot6to a longest toe (for example,6b) in the first direction1is defined as a foot length L1. A direction parallel to the plane4and intersecting (typically orthogonal to) the first direction1is defined as a second direction2(left-right direction2), and a direction intersecting (typically orthogonal to) the plane4is defined as a third direction3(height direction3).

The first direction1and foot length L1may be defined differently from the above. For example, a direction of a boundary line between left and right feet when the left and right feet are arranged to be in contact with each other may be defined as the first direction1, and a maximum length of each of the left and right feet in the first direction1may be defined as the foot length L1.

The foot length calculation unit26a(seeFIG.2) executes a step of the foot shape measurement method, that is, a foot length calculating step of calculating the foot length L1of the foot6.

As illustrated inFIG.3(a), when the rear portion of the foot6is viewed from the second direction2, a point that protrudes most within a heel range H1is defined as a protrusion point P1, a point that retracts most within an Achilles tendon range H2is defined as a retraction point P2, and a distance between the protrusion point P1and the retraction point P2is defined as L2in the foot length direction (first direction1). An upper limit of the heel range H1and a lower limit of the Achilles tendon range H2may coincide with each other, or the heel range H1and the Achilles tendon range H2may overlap each other.

A ratio (%) of the distance L2to the foot length L1is defined as a heel index. When the heel index is H,

The distance calculation unit30calculates the distance L2between the protrusion point P1and the retraction point P2for the rear portion of the foot6viewed from the lateral direction (second direction2) based on the 3D data25of which the input has been received by the input reception unit24. For example, the distance calculation unit30sequentially calculates coordinate values of the rear end (the end opposite to the toe in the first direction1) of a contour line of the foot6in the first direction1in each cross section while changing a cross-sectional position in the third direction3(height direction3) with respect to the cross section of the foot6parallel to the plane4. The distance calculation unit30extracts coordinate values of the rearmost side (side opposite to the toe) within the heel range H1and coordinate values of the foremost side (toe side) within the Achilles tendon range H2with respect to the coordinate values of the rear end in the first direction1in each cross section. The distance calculation unit30calculates an absolute value of the difference between the extracted coordinate values as the distance L2.

The distance calculation unit30executes steps of the foot shape measurement method, that is, (i) a protrusion point specifying step of specifying a protrusion point P1that protrudes most within the heel range H1for the rear portion of the foot6viewed from the lateral direction (second direction2), (ii) a retraction point specifying step of specifying a retraction point P2that retracts most within the Achilles tendon range H2for the rear portion of the foot6viewed from the lateral direction, and (iii) a distance measuring step of measuring a distance L2between the protrusion point P1and the retraction point P2in the foot length direction (first direction1).

The heel range H1and the Achilles tendon range H2may be a predetermined fixation range or may be individually determined based on the foot length L1calculated by the foot length calculation unit26a. For example, the foot length L1calculated by the foot length calculation unit26amay be multiplied by a predetermined coefficient to determine a range of the heel range H1and the Achilles tendon range H2, that is, a cross-sectional height (coordinate values in the third direction3).

The Achilles tendon range H2may be determined by multiplying the height of the protrusion point P1by a coefficient in a predetermined range, or may be determined by adding a dimension in a predetermined range to the height of the protrusion point P1.

In addition, an upper limit value and a lower limit value of the Achilles tendon range H2may be the same. For example, the height of the Achilles tendon range H2may be one height obtained by multiplying the height of the protrusion point P1by a constant coefficient, or may be one height obtained by adding a constant dimension to the height of the protrusion point P1.

The heel index calculation unit32calculates a heel index H indicating a ratio of the distance L2to the foot length L1, from the foot length L1calculated by the foot length calculation unit26aand the distance L2calculated by the distance calculation unit30using (Formula 1).

The heel index calculation unit32executes a step of the foot shape measurement method, that is, a heel index calculating step of calculating a heel index H which is a ratio of the distance L2to the foot length L1.

The classification determination unit34determines a classification to which the heel index H calculated by the heel index calculation unit32belongs, and calculates classification data corresponding to the classification. For example, when the heel index H is less than 3%, it is determined that the classification is A. When the heel index H is 3% or more and less than 5%, it is determined that the classification is B. When the heel index H is 5% or more, it is determined that the classification is C.

At least one of the distance, the heel index, and the classification to which the heel index belongs is displayed on a screen of the terminal16together with the foot length or the like, is displayed on a screen of a display device (not illustrated) that is disposed adjacent to the measurement unit12and that displays a measurement method or the like, or is output from a printer (not illustrated) disposed adjacent to the measurement unit12or a printer (not illustrated) coupled to the terminal16.

Note that the feature parameter calculation unit26may or may not include a protrusion point height calculation unit36that calculates a height (coordinate values in the third direction3) of the protrusion point P1of the foot6.

Next, an outline of data processing executed by the foot shape measurement system10will be described.

Data13measured by the measurement unit12is transmitted to the data processing unit20. In the data processing unit20, the 3D data generation unit22generates 3D data23based on the data13from the measurement unit12, and the input reception unit24receives an input of the generated 3D data23. 3D data25of which the input has been received by the input reception unit24is sent to the feature parameter calculation unit26and the communication unit28. The feature parameter calculation unit26calculates a foot length L1, a distance L2, a heel index H, and the like based on the 3D data25of which the input has been received by the input reception unit24, determines a classification to which the heel index H belongs, and calculates classification data assigned to the classification to which the heel index belongs. These feature parameters27calculated by the feature parameter calculation unit26are sent to the communication unit28. The communication unit28transmits data29for displaying or printing the feature parameters27in an appropriate format to the terminal16or the like.

FIG.4is an example of an image output from a printer (not illustrated) based on the data29transmitted from the communication unit28. As illustrated inFIG.4, the heel index and the classification to which the heel index belongs are printed below the foot length of each of the left and right feet.

The distance L2, the heel index H, and the classification to which the heel index H belongs obtained by the foot shape measurement system10can be used as indices for selecting a ready-made shoe.

When a ready-made shoe is designed so that, even when the foot length L1is different, when the heel index H is the same, the shape of the heel portion of the shoe is the same, it is easy to manufacture and select a ready-made shoe.

By manufacturing ready-made shoes having different shapes of the heel portion for each classification to which the heel index H belongs, it is easy to manufacture and select a ready-made shoe.

The foot shape measurement system10can incorporate a function of calculating an index related to the shape of the rear portion of the foot into a foot measurement system that measures the three-dimensional shape of the foot and calculates a representative index such as a foot length.

A foot shape measurement method executed by the foot shape measurement system10includes (i) a protrusion point specifying step of specifying a protrusion point that protrudes most within a heel range for a rear portion of the foot viewed from a lateral direction, (ii) a retraction point specifying step of specifying a retraction point that retracts most within an Achilles tendon range for the rear portion of the foot viewed from the lateral direction, and (iii) a distance measuring step of measuring a distance between the protrusion point and the retraction point in a foot length direction, and further, (iv) a foot length calculating step of calculating a foot length of the foot, and (v) a heel index calculating step of calculating a heel index that is a ratio of the distance to the foot length.

<Second Embodiment> A foot shape measurement system11according to a second embodiment will be described with reference toFIGS.5and6. The foot shape measurement system11according to the second embodiment has the same configuration as a part of the foot shape measurement system10according to the first embodiment, and calculates a feature parameter by using 3D data of the foot already measured and generated. The foot shape measurement system11executes a foot shape measurement method similarly to the foot shape measurement system10according to the first embodiment. Hereinafter, differences from the first embodiment will be mainly described.

FIG.5is a block diagram of the foot shape measurement system11according to the second embodiment. As illustrated inFIG.5, the foot shape measurement system11includes a display device40that displays an image on a liquid crystal panel or the like, an operation device42such as a touch pad or a mouse, and an information processing device44. The foot shape measurement system11is configured using a server, a personal computer, or the like. The display device40, the operation device42, and the information processing device44can be integrally configured using a notebook computer.

The information processing device44includes an input reception unit46, a feature parameter calculation unit48, and an output unit50. The information processing device44may be configured to be distributed to a plurality of servers or the like.

The input reception unit46receives an input of 3D data representing a three-dimensional shape of a foot. For example, 3D data generated by measuring the three-dimensional shape of the foot and stored in a database (not illustrated), a USB memory, or the like is input to the input reception unit46.

The output unit50generates data to be displayed on the screen of the display device40or data to be printed by a printer (not illustrated) based on the various feature parameters49calculated by the feature parameter calculation unit48according to the operation of the operation device42, and outputs the generated data to the display device40or the like.

FIG.6is an example of an image displayed on the screen of the display device40. As illustrated inFIG.6, the screen of the display device40displays an input reception unit60that receives an input of 3D data (for example, STL data), a range setting unit62for setting an upper limit value and a lower limit value of a heel range and an Achilles tendon range, a specified value setting button64for setting the upper limit value and the lower limit value of the heel range and the Achilles tendon range to specified values, a data output unit66that displays a file name, and an output button68.

The foot shape measurement system11executes data processing by operating the operation device42while viewing the screen of the display device40. For example, when the upper limit value and the lower limit value of the heel range and the Achilles tendon range displayed in the range setting unit62are set to desired values and the 3D data is dropped or pasted to the input reception unit60, the foot shape measurement system11automatically calculates feature parameters (distance, heel index, classification to which heel belongs) related to the shape of the rear portion of the foot together with a representative index such as a foot length, and displays a file name of output data including the calculated data in CSV format on the data output unit66. When the output button68is clicked, the foot shape measurement system11downloads the output data to a predetermined file, a storage medium, or the like.

The foot shape measurement system11according to the second embodiment calculates a feature parameter that can be used as an index for selecting a ready-made shoe that matches the shape of the rear portion of the foot from the 3D data of the foot already measured and generated.

<Conclusion> As described above, the foot shape measurement system calculates a feature parameter that can be used as an index for selecting a ready-made shoe. By arranging the ready-made shoes according to the index, it is easy to select a ready-made shoe that matches the shape of the rear portion of the foot.

Note that the present invention is not limited to the above embodiment, and can be implemented with various modifications.

For example, the feature parameter related to the shape of the rear portion of the foot calculated by the foot shape measurement system may be used for designing an order shoe. Further, in the above embodiment, the three-dimensional shape is measured by the measurement unit12, but instead of the data13measured by the measurement unit12, 3D data may be generated from data obtained by image capturing and image analysis. Furthermore, in the foot shape measurement method, the foot length L1and the distance L2between the protrusion point P1and the retraction point P2may be simultaneously or individually measured using a measuring instrument without using the 3D data generated by measuring the three-dimensional shape of the foot, the heel index may be calculated, and the classification to which the heel index belongs may be determined by a control table.

INDUSTRIAL APPLICABILITY

According to some aspects of the present disclosure, feature parameters related to the shape of the rear portion of the foot can be calculated. By arranging ready-made shoes using the feature parameter related to the shape of the rear portion of the foot as an index, it is easy to select a ready-made shoe that matches the shape of the rear portion of the foot.

REFERENCE SIGNS LIST