EP2120711A1

EP2120711A1 - Method and arrangement for the three-dimensional detection of the spatial shape of a foot

Info

Publication number: EP2120711A1
Application number: EP07856919A
Authority: EP
Inventors: Dirk Rutschmann; Christian Lott
Original assignee: corpuse AG
Current assignee: corpuse AG
Priority date: 2007-01-01
Filing date: 2007-12-19
Publication date: 2009-11-25
Also published as: US20100106061A1; WO2008080562A1; DE102007001402A1

Abstract

The invention relates to the optical detection of the spatial shape of spatially positioned feet, more particularly a method for the three-dimensional digitized detection of the spatial shape of at least one foot or both feet of a person in order to select or individually manufacture footwear. Said method encompasses the following steps: a desired position is established for the foot/feet, said desired position being predefined by the footwear that is to be selected or manufactured; the foot/feet is/are brought into the desired position with the help of a device that is preferably adjustable using a motor; the three-dimensional shape of the foot/feet is optically detected and digitized in the desired position. Also disclosed is an arrangement, by means of which one foot or both feet of a person is/are brought into a desired position in which the three-dimensional shape of the foot/feet is digitized in a primarily contactless manner. Said arrangement comprises a bottom plate, a first support, and a second support. The first and the second support are movable, preferably using a motor, parallel and perpendicular to the bottom plate in order to bring the foot/feet into the desired position.

Description

Method and arrangement for the three-dimensional detection of the spatial form of a

foot

The invention relates to a method for three-dimensional digitized detection of the spatial form of at least one foot or both feet of a person for a selection or individual production of footwear. The invention further relates to an arrangement with which a foot or both feet of a person is brought into a desired position in which the spatial shape of the foot / feet is then predominantly digitized without contact.

The detection of the spatial form, i. The 3-dimensional coordinates of the surface of feet for selecting suitable products or for dimensionally accurate production of these products, for obtaining anatomically and medically interesting data and similar applications today is preferably done with optical 3D scanners based on laser triangulation, the projection of structured light or close-range photogrammetry work. A particularly cost-effective arrangement of such a scanner is the so-called "lightbeam® 3D scanner" from corpus.e AG, Stuttgart (www.corpus-e.com), in which the foot to be digitized is provided with a specially marked elastic, tight-fitting The photogrammetric registration, ie the assignment of corresponding marks from the individual images, takes place on the basis of the specific coding of these marks as well as a likewise photogrammetrically marked base plate on which the customer to be digitized stands upright This method is described in a number of granted patents and patent applications, for example in the basic patent EP 0 760 622: Method and arrangement for the three-dimensional digitized detection of the spatial form of bodies or body parts (Inventor: Robert Massen).

Another commercially available from Shoemaster under the name

"INFOOT®" offered foot scanner (see www.shoemaster.co.uk) uses the laser light section procedure, whereby in each case only one foot, which on one Glass plate is scanned by means of an arrangement of three movable camera / laser line projector arrangements.

According to the state of the art, in the case of three-dimensional digitization of the fundamentally substantially shape-unstable feet, an only slightly controlled actual state of the foot shape is measured: the customer stands upright on an i. AIIg. flat bottom plate (for example a glass plate in laser triangulation scanners, which also digitize the sole of the foot or a photogrammetrically marked surface in the lightbeam® scanner).

Under the influence of body weight and body posture, the digitized foot assumes a spatial form which differs considerably from the later foot shape inside a well-fitting shoe: the sole of the foot is pressed more or less flat, depending on the body balance posture, the circumference measurements and the length measurements are distinctly different from those of a foot in walking motion.

In particular, in women's shoes with high heel foot shape is in normal use by the steep spatial position significantly different from the foot shape, which is determined in an optical scanner according to the described prior art in flat basic position. The data extracted from a 3D model of a foot digitized in this position is therefore not suitable for selecting a suitable model or producing an individual shoe. These difficulties have u. a. led to the fact that in the so-called mass-customization business practically no women shoes selected with the help of 3D scan data or individually manufactured are offered.

However, there is a great deal of interest in the various applications of foot digitization both in the field of prosthetic restoration, in the area of so-called mass customization and in special shoes such as sports shoes, protective shoes, etc. before the measurement in an anatomically desired foot digitizing Position to then digitize the so-fixed foot in a defined target state. In this case, this target position can be defined not only by a certain geometrical spatial position, for example, by a certain angle between the sole of the foot and toe plateau, but also by the achievement of certain physical characteristics such as a specific pressure distribution of sole pressure from heel to ball.

Especially with prosthetic shoes, which in addition to the actual

Footwear is also an adjunct to correcting non-foot-related conditions such as pelvic obliquity, it is very important to derive this shoe from a foot model which is in the correct

Correction position is digitized.

There is therefore a considerable economic and technical interest in a method for obtaining the three-dimensional shape of feet with contactless 3D scanners, in which the resulting foot model is adapted to the footwear to be selected or produced.

This is inventively achieved by a method with the steps of claim 1. It is further achieved by an arrangement having the features of claim 11, with which the foot to be digitized is brought into a desired position adapted to the footwear.

By digitizing the foot in a desired spatial position, the 3D model of the foot created by 3D digitization provides much more precise data than is needed to select a best-fit shoe from an existing collection or to produce an individual custom shoe the 3D model of a foot, for example, a lady's foot, which stands up flat and deformed accordingly different, is possible. Since also derived usual length and circumference measurements can change by up to several shoe sizes due to the foot deformation associated with the changed spatial position, it is immediately clear that digitizing a foot in such an optimal spatial position leads to much better matching shoes.

This argument is likewise decisive in the digitization for the purpose of producing orthopedic shoes, so that the method according to the invention also provides 3D models which fit better and also length and circumference measurements derived therefrom much better than in the case of

Foot scanners according to the prior art happens. Advantageously, the foot or feet are successively brought into different desired positions and determines the three-dimensional spatial form in each of these positions. Thus, deformations of the foot can be considered, for example, while walking. Preferably, the supports that bring the foot in the desired position, adjusted by motor.

In the preferred embodiment, the arrangement with which the foot is brought into the desired position, pressure sensors and the desired position is determined at least by a predetermined pressure distribution. Thus, e.g. From the anatomical point of view desired target positions are evaluated by the customer and the customer is advised accordingly.

The concept of the invention is illustrated by way of example but not limited to the digitization of a female foot, using a two-part motorized device for raising the arch of the foot and the heel, and the contact pressure at the three locations: forefoot, arch and heel via pressure sensors incorporated in the device is determined. Please refer to the following pictures:

Figure 1 shows an inventive arrangement in the digitization of a first foot; and

Figure 2 shows the erfihdungsgemäße arrangement of Figure 1 in the digitization of a second foot.

The inventive arrangement in Figure 1 comprises a bottom plate 10, a first support 12 and a second support 14. The supports and the bottom plate are preferably made of transparent material, so that they have the least possible interference in the optical detection of the spatial form and the digitizer not or only slightly restrict. Depending on the digitization method used, the bottom plate has photogrammetric marks. The idea of the invention is independent of the predominantly non-contact optical digitizing method used, whether on the basis of laser triangulation, pattern projection, photogrammetry, silhouette detection or other methods known to those skilled in the art of 3D digitization. The foot 16 to be digitized rests with the forefoot on a bearing surface 17, with the arch of the foot 20 on the first support 12 and with the heel 22 on the second support 14. The supports are preferably to be changed pneumatically or hydraulically or by motor control. In the exemplary embodiment, the supports 12 and 14 are marked (not shown) so that they can be identified by the digitizing system. This can be done for example by an optical coding with a barcode, with an RFID chip or a similar marking method, but also by a shape recognition of the digitized supports themselves.

It is also conceivable to bring the foot by mechanical positioning devices in the desired position, which do not consist of discrete vertical axes as shown in Figure 1, but flat position the sole of the foot in the room. Such positioning devices may consist, for example, of inflatable flexible hollow bodies. Also, simplified embodiments of the devices, e.g. in the form of a collection of different footrests, which correspond to the different spatial positions, are conceivable.

In the exemplary embodiment, a pressure sensor 24 is provided in the support surface 16, a pressure sensor 26 is provided in the first support 12, and a pressure sensor 28 is provided in the second support 14. The supports 12 and 14 are vertically movable. They are set in Figure 1 so that the lady's foot is brought into a soli position, which corresponds both to the desired fashionable shoe style corresponding foot position, as well as anatomically desired pressure conditions between the contact pressure of the forefoot 18 (for example, at the location of the bale), the arch of the foot 20 and the heel 22 are present. Advantageously, it is also possible to provide sensors for static and / or dynamic pressure values and / or temperature values and / or electrodynamic values at different points of the sole of the foot. The supports 12 and 14 are moved vertically by motor but also a mechanical adjustment is conceivable to come to the desired position.

Preferably, each of the struts 12 and 14 comprises two adjacent, separately movable devices whereby tilting of the foot about its longitudinal axis is achieved by different heights of the left and right devices. Such foot positions are for example in the Production of orthopedic footwear desired, which should correct a pelvic tilt.

FIG. 1 likewise shows schematically an evaluation unit 30, wherein the evaluation unit contains a database in which nominal ranges for the measured values of the pressure sensors are stored as a function of different SoII positions. The evaluation unit may be, for example, a computer.

The arrangement further comprises a graphical output device, preferably coupled to the evaluation unit, on which proposals for a best-matching depending on the measurements of the sensors, the data of the spatial shape of the foot / feet and anatomical and / or medical data of the customer

Shoe and / or be made for a custom-made shoe.

The sensor measured values can either be transmitted to the evaluation unit directly via a connection or entered by the user via a human / machine interface.

According to the invention, a desired position is initially determined with the customer, which is predetermined by the footwear to be selected or produced. In the exemplary embodiment, therefore, the customer is presented with a series of suggestions based on a first database which contains information about the shoe shapes that can be supplied or produced and the pressure distributions which are desirable depending on the individual anatomy of the customer. According to the invention, the access via this database takes place via all or a selection of the following criteria:

the gender of the customer

a preselection of the desired shoe shapes by the customer

possible use restrictions named by the customer such as

Running shoe, dance shoe, street shoe, sports shoe, etc

anatomical measurements such as total body weight, general foot geometry,

the latter being entered via an input medium such as a keyboard or touchpad, or automatically determined from a 3D digitization of the foot itself in a home position. After so the desired position or the target positions is / are determined, the foot of the customer is then placed in the determined from the database matching (s) position (s) and required for the selection of a best-fit shoe or the manufacture of an individual shoe digitization of the foot in This digitized from the shoe style and anatomy optimal position.

The desired position can be predetermined by geometric specifications or by sensor measured values. Preferably, both specifications are observed. As a rule, it will often not be possible to achieve anatomically desired pressure ratios for all possible fashionable shoe styles. Therefore, if the given sensor readings are not achieved at a certain geometric position, the customer is offered another footwear which is better adapted to the individual anatomical conditions.

In one embodiment, the foot is brought into different spatial positions during the digitization and in each case a section of the spatial form is determined for the respective foot position. As a result, e.g. the foot can be detected in a left and right side view in different spatial position and thus, for example, the change in the foot length are determined as a function of spatial position from a single digitizing process, which means a gain of time.

FIG. 2 shows the arrangement according to FIG

Damenfuß 16 'is adjusted. For this purpose, the supports 12 and 14 as indicated by arrows 32 and 34 were moved parallel to the bottom plate 10. Preferably, this displacement is motorized.

The description of the invention was based on a preferred embodiment. This application of the digitization of a lady's foot is to be understood as merely exemplary and does not limit the

Inventive idea. A use of more than two vertical supports, a different mechanical design of the device for changing the

Foot position, applications in the fields of orthopedic shoes and boots, athletic footwear and medical diagnostics and

Research in the field of foot medicine is included in the concept of the invention. Essential to the inventive idea compared to the state of the art of optical 3D digitization of feet is that the foot in front of the

Digitization is brought into a desired spatial position, which results from the desired geometric position and / or physical measurements, in particular pressure values.

A further idea of the invention is, in particular for the individual production or best-fit selection of orthopedic footwear, to select from a series of spatial positions determined in different desired positions that represents an optimal compromise between anatomically / therapeutically desirable form, availability and production costs.

Claims

claims

Method for the three-dimensional digitized detection of the spatial form of at least one foot (16, 16 ') or both feet of a person for a selection or individual production of footwear, the method comprising the following steps:

- Specifying a desired position for the foot / feet (16, 16 '), which is determined by the footwear to be selected or produced;

- bringing the foot / feet by means of a preferably motorized adjustable device in the desired position;

- Optical detection and digitization of the three-dimensional spatial form of the foot / feet in the desired position.

A method according to claim 1, wherein the foot (s) (16, 16 ') is sequentially brought into different desired positions and the three-dimensional spatial form is determined in each of these positions.

3. The method of claim 1 or 2, wherein the desired position is predetermined by geometric specifications.

4. The method according to any one of claims 1 to 3, wherein in the device at least one physical sensor (24, 26, 28) is installed and for the SoII position a sensor reading is predetermined.

5. The method of claim 4, wherein a plurality of sensors (24, 26, 28) are provided and the sensors provide static and / or dynamic pressure values and / or temperature values and / or electrodynamic values at different locations of the sole of the foot.

6. The method of claim 4 or 5, wherein the sensors (24, 26, 28) provide readings about the posture of the person.

A method according to any one of the preceding claims, wherein the foot (s) is placed in a desired position in which the heel (22) is higher than the toe plateau (18).

8. The method according to any one of the preceding claims, wherein the foot (16, 16 ') is tilted to reach a desired position along its longitudinal axis.

9. The method according to any one of the preceding claims, wherein the desired position / positions of a first database are taken in response to at least one of the following:

- Gender of the person

- Preselection of the desired shoe shape

- Possible restrictions of use such as running shoe, dance shoe, street shoe, sports shoe, etc. - anatomical measurements such as total body weight, general

Foot geometry.

10. The method according to any one of the preceding claims, wherein a selection of the shoe clothing is done using a second database, in which rules for the selection or production of a best fitting shoe depending on the determined spatial form and / or data derived therefrom, the customer's wishes, the customer anatomy , medical rules and shoe production conditions.

11. Arrangement for bringing a foot (16, 16 ') or both feet of a person into a desired position, in which the spatial form of the foot (s) is primarily digitized without contact, the arrangement comprising:

- A bottom plate (10) having a support surface on which the forefoot (18) rests;

- A first support (12) on which the arch (20) rests; - A second support (14) on which the heel (22) rests; wherein the first and the second support (12, 14) parallel to and preferably perpendicular to the bottom plate (10) are preferably movable by motor to bring the foot / feet (16, 16 ') in the desired position.

12. Arrangement according to claim 11, wherein both supports (12, 14) each comprise two separately movable parts, which are arranged to each other such that the foot (16, 16 ') is tilted at different heights of each two parts about its longitudinal axis.

13. Arrangement according to one of claims 11 or 12, wherein the first and second supports (12, 14) are realized by pneumatically and / or hydraulically deformable hollow body.

14. Arrangement according to claim 11 to 13, wherein in the bearing surface (17) of the bottom plate (10) has a first pressure sensor (24), in the first support (12) at least a second pressure sensor (26) and in the second support (14) at least a third pressure sensor (28) are provided, wherein the pressure sensors are adapted to measure the contact pressure of the forefoot, the arch of the foot or the heel.

15. Arrangement according to claim 14, further comprising an evaluation unit (30), wherein the evaluation unit contains a database in which, depending on the desired position, target ranges for the measured values of the pressure sensors (24, 26, 28) are stored.

16. Arrangement according to one of claims 13 to 15, further comprising a graphical output device, on the basis of the measurements of the sensors, the data of the spatial form of the foot / feet and anatomical and / or medical data of the customer proposals for a best-matching Shoe and / or be made for a custom-made shoe.

17. Arrangement according to one of claims 11 to 16, wherein the bottom plate (10), the first support (12) and the second support (14) are made at least substantially of transparent material.