FR3077725A1 - DEVICE FOR DETERMINING FOOT SUPPORT - Google Patents

Abstract

The invention relates to a device for determining the type of plantar support of a person in a standing position comprising: - a horizontal base covered with a cover (2) formed of an upper plate (3) on which are arranged two locations (5, 6) surface planes adapted to lay the feet thereon, - sensors capable of providing an electrical response proportional to the pressure undergone, arranged on the upper face of said base in two parallel bands underlying the two locations, the geometric position is marked on the strip, and - an electronic module, comprising: - means for collecting the electrical signals generated by said sensors and record the value of the pressure undergone associated with the position of said sensor, - means for determining the hold (7) of each foot on its location (5, 6) and to define three ranges of said right-of-way corresponding to three underlying sensor zones; determine the pressure exerted on a given zone, and the contribution of said pressure to the total pressure exerted on the right-of-way (7), - means for comparing the contribution of the pressure exerted in each zone with a theoretical contribution calculated according to a key predefined distribution, in order to determine the type of foot support of said person. Figure to be published with the abstract: Fig. 2

Description

Title of the invention: DEVICE FOR DETERMINING THE FOOT SUPPORTS The present invention belongs to the field of devices used to assess the morphological characteristics of an individual and more particularly of his feet.

It relates to a device for determining the type of plantar support of a person in a standing position. It also relates to a method in which said device is implemented.

The practice of running, on a track, on the road or in a natural environment has grown considerably over the past twenty years. The ease with which one can indulge in this sport anywhere, without bulky equipment and without organizational constraints, attracts people of all physical condition and of all ages. It is enough to have a pair of shoes to put on, often badly named tennis shoes, to go running to relax or to train.

If running is generally beneficial for health, it can in the long run cause pain or even tendon or muscle damage. The joints are also highly stressed. This is why, it is recommended to wear shoes specifically intended for running.

Many models of shoes are offered to runners, depending on the type of practice desired, occasional or regular, for leisure or in competition, .... Manufacturers targeting an audience increasingly aware and concerned about find suitable shoes, offer models whose displayed characteristics take into account the distances that will be covered during training and races, more or less flexible or uneven types of terrain. Certain models are also presented as adapted to a particular type of support of the foot.

Indeed, the proper morphology of the foot also plays an important role in the choice of footwear, particularly the shape of the arch of the foot, because each of the strides produced rests on this small surface which supports the entire weight of the body, distributed over seven support zones: mainly the heel and the metatarsus, and alternatively the pulp of the five toes. There are commonly three types of support:

[0007] - universal support, which concerns around 45% of the population and corresponds to a stable base, with flat support;

- pronator support, the most widespread with 50% of people who have marked internal support (slight pronation being normal);

- And finally, the supinator support, that is to say which is carried out on the outer part of the foot, for about 5% of people.

It is essential that the runner knows what is his type of support when he acquires a pair of shoes dedicated to running so that he can make a wise choice, because a bad position of the foot, and with it poor posture during the race, may cause premature wear of the joints, bones, tendons.

However, this data is often ignored by the person in front of the sports shoe department, who is unable to make his choice even though the manufacturers offer various models, bearing the mention of the type of support to which they are adapted.

The nature of the supports is commonly determined by podiatrists and other specialists who have equipment to analyze the morphology of each. For example, an impression of the sole of the foot can be performed for orthopedic correction, either by means of an inking mat (pedometer), or by means of a mat provided with pressure sensors commonly called electronic pedometer. . These impressions are intended to reveal the support areas of the foot to determine, after interpretation, the corrections to be made to compensate for certain anatomical features of the patient's arch.

We also know devices called podoscopes used by doctors, podiatrists and surgeons to perform clinical observation of the foot in order to correct any malformations. These devices generally include a case, the upper face of which consists of a transparent window on which the patient stands, and in which a reflecting mirror is placed at an inclination intended to allow the practitioner to observe the sole of the patient's foot. . These devices, which have been known for a long time, are today associated with optoelectronic systems for recording and processing images producing a cartography of each foot, colored zones being represented as a function of the pressure exerted at different points by the sole of the foot. Devices called podoscan or podoscanner offer the possibility of a 2D or 3D analysis of the footprint, for the automated design of corrective orthopedic insoles.

These devices are sophisticated and complex. They must be handled by qualified professionals capable of analyzing the results, generally for therapeutic purposes, or in the service of high performance sport. They must be adjusted for each patient according to their size and carefully configured to provide usable results. They are also heavy, fragile and non-transportable, which forces patients to travel to a specialist. The calculations are made using external computer systems, which consume a lot of energy. Therefore, they are not suitable for use by the public, in a place open to all such as commercial premises.

There is therefore an unmet need to date to have a device allowing everyone to know what type of plantar support belongs the morphology of his foot. The present invention meets this need by offering a space-saving device, which can for example be installed in front of a rack in a sports store and used on site in a very simple manner by an uninformed user, to provide him in a few moments with this useful information the choice of shoes.

An objective of the present invention is thus to offer a device making it possible to define the type of support for a person's feet in a simple and rapid manner and to deliver the expected result almost instantaneously by direct indication and unequivocal of the category to which it belongs (universal, pronator or supinator). Another objective of the invention is to use a single device, whatever the size and especially whatever the size of the user. According to another objective of the invention is that it is not necessary to manipulate the device to adapt it to the size of the user. Another object of the invention is to provide an apparatus which can operate autonomously for long hours. Finally, an objective of the invention is to offer a robust and affordable device.

The invention meets this need and remedies the drawbacks of known systems by proposing a device for determining the type of plantar support of a person in a standing position, which comprises:

a base extending along a horizontal main plane, covered with a cover formed by a flat upper plate extending by lateral flanges holding it to the base, plate on which two flat locations are formed in the form of parallel strips, l '' one left, the other right, with a surface suitable for placing the left foot and the right foot respectively,

- sensors capable of providing an electrical response proportional to the pressure undergone, said sensors being distributed in two assemblies arranged on the upper face of said base in two parallel strips underlying the two locations that the tray comprises, said sensors being arranged in at at least two networks occupying all or part of the surface of said strips, and the position of each sensor being identified by its geometric coordinates on the strip, and

- an electronic module housed in a compartment in the base, comprising:

means for collecting the electrical signals generated by said sensors and recording for each sensor the value of the pressure undergone associated with the position of said sensor,

means for determining the footprint of each foot on the dedicated location of the platform and for defining three ranges of said footprint corresponding to three areas of underlying sensors,

means for determining the pressure exerted on a given area, and the contribution of said pressure to the total pressure exerted on the right of way, and

- Means for comparing the contribution of the pressure exerted in each zone with a theoretical contribution calculated according to a predefined distribution key, in order to determine the type of plantar support of said person.

The device according to the invention is externally presented as a platform extending along a horizontal main plane when installed in the operating position, that is to say placed on a floor, itself horizontal. It is specified here that, more generally, in the description which follows, the terms above, below, upper, lower, etc. refer to this operating position of the device.

The cover is only visible, with its upper plate intended to receive the feet of the user and its lateral edges tightly enveloping the base so as to keep it fixed to it. The tray is substantially flat and has two locations on which the user will place his feet. These dedicated locations conveniently adopt (but without obligation) the form of strips, that is to say rectangles clearly longer than wide, of sufficient size to receive feet of all sizes. The device is lateralized, so that the right foot will be placed on the right strip and the left foot on the left strip. In this way, the front (or distal) part occupied by the front part of the foot and the toes and the rear (or proximal) part corresponding to the heel are also identified. Colored or luminous markings are provided on the tray to allow the user to orient himself correctly when he installs himself on the device.

The base constitutes the structural armature of the device. It can be made of a solid block in which cavities are made to place the electronic components, or of a rigid case provided with adequate compartments. This last option is easily implemented by known plastics techniques.

The base has an upper face on which are arranged sensors which will deliver an electrical response proportional to the pressure which will be applied to them. The sensors are divided into two sets occupying two right and left bands, which are underlying, that is to say located below, the two bands of the plate. It is therefore understandable that when a person is installed on the platform, the soles of his feet exert a more or less strong pressure at different points depending on his morphology and the plantar supports which are specific to him. The pressures exerted on the dedicated locations are transmitted to the underlying sensors. We note that it is equivalent to speak of pressure exerted at a point on the plateau and pressure undergone by the underlying point.

Each set of sensors (in general, right and left) can be designed as a single network connected to the electronic module, or else be divided into sub-assemblies forming several networks. This last option may prove to be advantageous for optimizing the arrangement of the connections with the electronic module in order to limit the bulk and improve the signal transmission. In any event, each sensor occupies a position identified on its strip by its geometric coordinates, in a previously defined coordinate system.

The device according to the invention also comprises an electronic module housed and protected in the thickness of the base. It includes the necessary connections to receive the electrical signals coming from the sensors. It also includes a microcontroller configured to process the electrical signals received from each sensor. It is in particular able to express the value of the pressure corresponding to the electrical signal and to record this value associated with the position coordinates of the sensor concerned. The electronic module is also configured to process the data thus recorded in order to determine the type of plantar support of said person, as will be explained in detail below.

However, it is important to emphasize now that the data processing includes a step where we define the grip of the sole, that is to say all the points of contact between the sole and the surface of the plateau, generating a non-zero electrical signal. This hold on the plateau has its counterpart at the level of the underlying sensors. Then, we search for three maximum pressure values in three sensor zones in relation to three areas of the right-of-way.

These maximum values are the mark of the main plantar supports of the user, whose position is representative of the dimension of the foot to be analyzed. In this way, the system will continue processing the data based on the individual dimensions of the user, without the need to make any adjustments. The pressure experienced by each area of the foot can then be compared to a reference pressure which is a fraction of the total pressure taken into account for the foot. The result of the comparison makes it possible to conclude as to the type of plantar support of the person standing on the device which is the subject of the invention.

The number of measurement points is an important criterion for obtaining a reliable result for all sizes and all plantar conformations. This is why, according to a preferred characteristic of the present invention, each set of sensors comprises from 50 to 100 sensors, all connected to a microcontroller capable of processing the signals transmitted. There is thus a device counting a total of 100 to 200 sensors arranged under the dedicated locations of the plate, occupying all or part of the surface of the strips.

According to a particular embodiment of the invention, each sensor assembly comprises two networks of sensors occupying at least the distal part and the proximal part of the strip on which they are arranged. We understand that these two parts have a variable relative situation depending on the length of the foot. This problem can be remedied by providing that the distal part is wide enough to accept sizes ranging for example from 35 to 47 (according to French standards), or even more. The proximal part can be more localized on condition of encouraging the user to place his heel at a predefined location in the dedicated location. One can for example provide a visual cue, such as an indicator light or a screen-printed pattern attracting his attention to guide it simply without imposing a strict position on it. In general, the most sensitive parts (especially the richest in sensors) can be identified by colored patterns, promoting optimal spontaneous placement.

Different types of sensors can be used for the implementation of the device object of the invention. Preferably, the sensors are chosen from capacitive force sensors, piezoelectric force sensors or force detection resistors. Force detection resistors, also called ESR for Eorce Sensing Resistor, are particularly suitable. These are components made up of a thick layer of polymer whose resistance decreases as the force applied perpendicular to its surface increases. They are insensitive to vibrations and noise, and have a wide impedance range allowing the use of simplified electronics, unlike piezoelectric polymers. In addition, if their accuracy is not very high, they are robust enough to operate during millions of cycles and they are economical. They consume much less current than the other components. Those skilled in the art know these components, which they will be able to assemble from elementary cells or matrix networks (sensors pre-assembled on a common support).

The sensors are subject to the upper face of the base which is located a short distance from the lower face of the plate. According to an advantageous characteristic of the invention, the plate and the upper surface of the base are placed at a spacing of 0.5 mm to 1 mm. The weight of a user installed on the device will slightly bend the plate in certain places which will come into more or less pronounced contact with the sensors. The plate is designed as a flat plate of a synthetic material whose thickness can be for example between 0.2 mm and 1 mm. Those skilled in the art will be able to choose from the various known materials, for example PVC (polyvinyl chloride), polyethylene, polypropylene or the like, that which meets the criteria sought in terms of rigidity and thickness.

According to a particularly interesting embodiment, the device according to the invention can also be covered with a shell of semi-rigid material compressing in a more or less accentuated manner under the effect of the weight, depending on the relief plantar. This shell first covers the locations dedicated to the feet. In this way, the contact surface of the sole of the foot is increased, without the total pressure exerted being modified. On the other hand, the distribution of pressures at the different points is more gradual and takes into account new parts of the arch. This eliminates, or at least compensates for, specific features in order to focus on the intensity of the supports, which improves the reliability of determining the type of support. This arrangement is particularly useful when the user has a slightly marked arch (flat feet).

Thus, according to an optional feature of the invention, the cover may include a shell of a material capable of deforming under the effect of plantar pressure to match the relief. This shell can take the form of a carpet applied to the tray as a whole or only on the locations dedicated to the feet. Conveniently, it is removable and envelops the tray and the side edges of said cover. It can be made of silicone of average hardness of the order of about 30 Shore A units, with a thickness of between 5 mm and 10 mm. It can thus be easily removed and washed. It also provides a welcome shock protection function given the environment in which the device is used.

As already indicated, the device object of the invention must be simple to use and accessible to all. This is why, it includes various functionalities favoring its use without learning phase, and the delivery of fast and unequivocal information. In particular, it includes one or more of the following means:

- means to indicate that a step of activating the measurement functions is in progress,

- means to invite the person to place their feet on the dedicated sites,

means for viewing the course of the determination, and

- Means for displaying the result of the determination.

The means in question are generally very simple visual (rather than audible) signals, for example in the form of indicator lights provided with LEDs (light-emitting diodes). These indicators can be configured to flash while a step is in progress, then adopt a fixed on or off state when it is finished. For example, during the determination process a flashing occurs, then a fixed state immediately indicates the result.

These provisions make it possible to guide the user and provide him with the relevant information, with great sobriety of energy. In this context, in a particularly preferred manner, the device according to the invention comprises autonomous means for supplying electrical energy. A housing is provided in the base for placing an accumulator there.

The device which has just been described makes it possible to carry out pressure measurements of the footprint and to analyze the data instantaneously. It provides in a few fractions of a second a static statement of the plantar supports of an individual, and defines its type of support (universal, pronator or supinator), without resorting to the interpretation of a professional or complex computer processing. It is completely autonomous from the point of view of its electrical supply, as well as that of data processing which is carried out by the device itself, without external computer relay. It is robust and light, so it can be moved manually, to be installed and work everywhere, without risk of damage.

The present invention also relates to a method implementing the device described above. Thus, the subject of the invention is a method of determining the type of plantar support of a person using a device as described above, said person standing upright, the left foot and the right foot placed respectively. on the two dedicated slots on the tray. This process includes the steps of:

a) - activate the measuring functions of the device,

b) - collecting the electrical signals delivered by the sensors and recording for each sensor the value of the pressure undergone associated with the position of said sensor,

c) - for each leg, determine the footprint on the dedicated location of the platform and define three areas of said footprint corresponding to three areas of underlying sensors,

d) - for each sensor zone, determine the pressure exerted on said zone and the contribution of said pressure to the total pressure exerted by the right-of-way,

e) - for each zone, compare the contribution of the pressure determined in d) with a theoretical contribution calculated according to a predefined distribution key, and

f) use the result of said comparison to determine the type of plantar support of said person.

Alternatively, the method comprises in step a) the display of an invitation to stand on the tray by locating each of the feet on the dedicated locations. This invitation can take the form of a solid lit LED.

At the end of step b) there are pressure-position pairs for all the sensors, which constitute a mapping of the plantar pressure, each sensor being more or less stressed, or even not at all if no pressing n 'is saved at a given point. It goes without saying that we record and process this data separately for each foot, in a similar but independent manner.

According to a characteristic of the method according to the invention, in step c), the non-zero values of the pressure are selected with the geometric coordinates of the requested sensors, all of these coordinates defining the plantar area of the individual. The sensors used are those for which the pressure is not zero.

Still in step c), the plantar area is divided into three areas, namely two front areas, one of which is external PI and the other internal P2, and a rear area P3, corresponding respectively to three zones of underlying sensors Z1, Z2, Z3. This division can be done on the basis of dimensional or analytical criteria, or by combining the two approaches. For example, we can define a rear shelf as occupying 1/3 for example of the length of the right-of-way, then divide the remaining part into two halves along a straight line passing through the center of the heel and the front toe. It is also possible to take more account of the natural shape of the foot, and to separate the front parts with a curved line along the curve of the outer edge of the foot. An analytical approach can also be used, according to which three maximum pressure values associated with sensors distant from each other are sought and the limits of the ranges are defined as a function of their position. Whatever approach is chosen, it is based on the fact that the human foot has three main supports located in well defined regions (heel and internal and external forefoot), with of course differences from person to person. '' which justify the use of this support determination process.

The division of the footprint into beaches allows to bring out three master sensors representative of these three anatomical supports. Thus, according to a preferred characteristic of the method according to the invention, in step d), one searches in each of the zones Z1, Z2, Z3, the sensor subjected to the maximum pressure to which the status of master sensor C1, C2 is assigned. and C3; a support area A1, A2, A3, including said master sensor and a series of peripheral sensors is defined in the vicinity of each master sensor, and the sum of the pressures undergone by the sensors belonging to said support area is calculated. The extent of the support zones in the vicinity of the master sensors can be defined in different ways. However, it must be large enough to involve several peripheral sensors, ideally at least five sensors.

Thus, according to a variant of the method according to the invention, each of the support zones A1, A2, A3 comprises the sensors located within a predefined radius around the master sensor C1, C2, C3. The radius can be fixed once and for all, for example equal to 30 mm, or it can be defined by the system taking into account the size of the foot, for example 1/4 of the width of the forefoot. A non-overlapping condition can be added so that a sensor is not within the perimeter of two support zones. The sensors located inside a support zone thus defined are retained for the following stages of the process.

According to a characteristic of the method according to the invention, in step d), the contribution of each support zone is calculated relative to the sum of the pressures undergone by the sensors solicited by the footprint. This is to define what is the pressure supported by each support zone, and calculate the part that this pressure represents in relation to the total pressure exerted on the right of way. The reader's attention is drawn to the fact that the absolute values of the different pressures are not significant in themselves or taken separately, since the analysis is based on comparisons of values between them.

In the following step e), a theoretical contribution of each support zone is calculated using a pressure distribution key. According to a preferred embodiment of the method according to the invention, the pressure distribution key used to calculate the theoretical contribution of the pressure on each support area is defined as affecting 2/3 of the total pressure in the area of rear support A3, and 1/6 to each of the front external Al and internal A2 support zones. This distribution key is based on the results of anatomical studies of the population. It appeared unexpectedly that the distribution key defined here, based on general anatomical balances, could be applied to limited fractions of the arch, namely the judiciously chosen support zones.

At this stage, information is available on the distribution between the three support zones of the total pressure recorded by the requested sensors. There is also a theoretical distribution between the three support zones of the total pressure recorded by the requested sensors. The theoretical contributions are taken as references in the comparison with the measured contributions (actual), respectively for each zone.

The final determination of the type of support can now be made, based on the difference E observed between the measured and theoretical contributions, according to the following approach. When the plantar support is universal, the pressure exerted on the two front support zones A1 and A2 is identical to the theoretical reference contribution. When the pressure recorded on the external support zone is greater than the theoretical contribution, the support is of the supinator type; and conversely when the pressure recorded on the internal support zone is greater than the theoretical contribution, the support is of the pronator type.

In practice, it is considered that the support is universal even if there is a certain difference E to the theoretical contribution or, more precisely up to a certain degree of difference E% to the theoretical contribution. By expressing the difference in percentage relative to the theoretical reference pressure, that is to say as a pressure ratio, the weight of the user is taken into account at the same time, since the pressures are proportional to the weight of the person. The degree of deviation E% tolerated is fixed beforehand, in a range generally between 8% and 20%, according to the choice of the manufacturer. For example, we can consider that support remains universal up to a deviation from the theoretical contribution, of the order of 10%.

This is why, according to an embodiment of the method according to the invention, in step f) the difference E observed between the measured and theoretical contributions is calculated and said difference is used to determine the type of plantar support of said person as follows:

- if the pressure recorded on the external front support zone is more than E% greater than the value of the theoretical contribution, the support is of the supinator type,

- if the pressure recorded on the internal front zone is more than E% greater than the value of the theoretical contribution, the support is of the pronator type,

- if neither of these two conditions is met, the support is of universal type.

It is emphasized here that the device described here is not a medical device, which in fact makes it useful. It provides an indication which reflects a type of stride of its user based on a morphological tendency (pronator, universal, supinator).

It is further noted that the type of support is for each individual more or less marked. A morphology deviating little from the universal support can be supported by certain models of shoes designed to better support the arch. In an alternative embodiment, the device according to the invention makes it possible to use the quantitative result obtained (the value of the difference between the measured and theoretical contributions) and to compare it with the technical information provided by the shoe manufacturers. of sports, in order to put them in adequacy and to propose a model of shoe or a specific range in the display of the results. A person skilled in the art can easily develop such an algorithm. The result can be displayed by designating which of the three types of support has been found, or by more quantitative and nuanced signage, by displaying a cursor on a slide or other display mode.

When the device is initialized, its operation is then extremely rapid. To avoid errors due to a poorly established posture of the person, it is recommended to repeat several cycles of data acquisition and exploitation. Several contribution values are then obtained for each support area, which can be averaged before concluding with the determination of the type of support. Thus, advantageously, in the method according to the invention, steps b) to d) are repeated at least N times, N being at least equal to 5, preferably at least 10, and more preferably at least 30, to determining N values of the pressure exerted on said zone, and the average of the N values is used to determine the contribution of said pressure to the total pressure exerted by the right-of-way.

The present invention will be better understood, and details will become apparent therefrom, in the light of the description which will be made of different alternative embodiments, in relation to the appended figures, in which:

[Fig.l] is a perspective representation of a device according to the invention.

[Fig.2] is a schematic representation seen from above of the device according to the invention.

[Fig.3] is a bottom view of the base of a device according to the invention showing the electronic assembly.

[Fig.4] is a representation of the support zones determined according to the invention.

EXAMPLE 1 - Structure of the determination device [0057] The device shown in FIG. 1 comprises a cover 2 formed by a flat upper plate 3, extended by lateral flanges 4. The plate takes the form of a flat plate whose thickness is approximately 1 mm, which gives it a slight flexibility . The plate 3 and the flanges 4 completely cover the rigid base 1 and keep it fixed. The plate 3 and the upper surface of the base 1 are mounted at a spacing of 0.5 mm to 1 mm. The assembly is presented as a platform, horizontal when it is placed in the operating position on a floor, of sufficient dimensions to accommodate the feet of large sizes, with for example a length of 40 cm for a width of 35 cm.

The plate 3 has two locations 5, 6 on which the user will place his feet, in the form of bands placed parallel on either side of the plate 3. The surface of the bands is identified by a light frame, ( here by cross bars), while a more pronounced pattern indicates to the user which way to place his feet. The device is thus oriented and lateralized.

Two sets of FSR sensors (not shown) are installed on the upper face of the base 1, in two sets occupying two strips underlying the two strips of the plate. Each set of sensors is divided into two subsets forming two networks. The sensors are connected to a microcontroller 8 via four printed circuits 18. Two networks (right and left) are arranged so that the sensors are at the level of the user's heels. The user is encouraged to place his heels directly above these sensors thanks to an indicator light 9 provided on the plate 3 at the appropriate place, reinforced by a screen-printed pattern 10. Two other networks of sensors are arranged towards the front to detect the pressure of the users' forefoot.

The device is designed to guide the user. In particular, it includes various visual signals that are easy to interpret, in particular using three indicator lights 12 fitted with LEDs (light-emitting diodes) which are placed on the central part of the plate 3 and indicator lights 9 provided at the heels. A switch 11 enables the electronic system to be started. During the activation phase, all the LEDs light up cyclically, creating a rapid sweeping effect. Once the device is ready, only lights 9 remain on so that the user installs his feet. During the measurement phase, the three central LEDs 12 flash, then after a few seconds one of them remains on alone, announcing the result of the determination. A label 13 mentions the type of support of the user. Other guide schemes can of course be imagined without difficulty by a person skilled in the art.

The device is equipped with a battery 14, the autonomy of which allows operation for several days, taking into account the low consumption of the selected components.

EXAMPLE 2 Silicone Cover The device can be used with a cover (not shown) enveloping the plate 3 and the side edges 4 of the cover 1. This cover is here made of transparent silicone 6 mm thick, molded to the shape of the cover 1. Under the effect of the pressure, it deforms and adapts to the plantar relief, compensating for the specifics of plantar morphology to refine the determination of the type of support. The elasticity of the cover allows it to be removed and cleaned.

EXAMPLE 3 - Methods for determining the plantar supports [0064] After the apparatus has been started up and the user installed on the plate 3, the determination process begins. The pressures exerted on the dedicated locations 5, 6 are transmitted to the underlying sensors of the base 1. The electrical signals delivered by the sensors are collected and recorded by the electronic module and processed by the microcontroller 8. For each sensor, the signal is converted into the value of the pressure undergone and is associated with the position of said sensor identified by its geometric coordinates in a predefined frame of reference.

We define the footprint 7 by selecting the sensors for which the value of the pressure is not zero and noting their geometric coordinates. This footprint 7 is divided into three areas P1, P2, P3, corresponding to three areas of underlying sensors Z1, Z2, Z3, as shown in FIG. 4. The division of the zones was carried out here by allocating 1/3 of the length of the right-of-way 7 to the rear zone Z3, and by drawing a middle line in the remaining front part to obtain an external front zone Zl and a zone internal front Z2.

Then is sought in each of these areas, the sensor subjected to the maximum pressure, said master sensor, respectively Cl, C2 and C3. From there we define a support area A1, A2, A3, centered on each of the master sensors, which here is a 2.5 cm radius disk. The contribution of each support zone is calculated in terms of pressure, with regard to the total pressure undergone by the requested sensors. Then, a new measurement cycle is initialized and the value of the contribution of each support zone is calculated again. After five cycles, the average values are established. It is specified that the same approach is adopted for the other foot noted B (see fig. 4, support zones Bl, B2, B3).

In parallel, a theoretical contribution of each support zone is calculated for the total pressure of the right-of-way. The distribution key used here is 2/3 for the rear support area A3, and 1/6 for the front support areas A1 and A2.

The observed and theoretical contributions can then be compared to conclude. If the pressure recorded on the support zone A1 is more than 10% greater than the theoretical contribution, the support is of the supinator type. If the pressure recorded on the support area A2 is more than 10% greater than the theoretical contribution, the support is of the pronator type. In other cases, support is universal. The corresponding indicator light is on on tray 3 indicating the result to the user.

Claims (1)

Device for determining the type of plantar support of a person in a standing position, characterized in that it comprises: - a base (1) extending along a horizontal main plane, covered with a cover (2) formed by a plate (3) upper plane extending by lateral flanges (4) holding it to the base (1), tray on which are arranged two locations (5, 6) planes in the form of parallel strips, one left, the other right, with a surface suitable for placing the left foot and the right foot respectively, - sensors capable of providing an electrical response proportional to the pressure undergone, said sensors being distributed in two assemblies arranged on the upper face of said base in two parallel strips underlying the two locations that the plate (3) comprises, said sensors being arranged in at least two networks occupying all or part of the surface of said strips, and the position of each sensor being identified by its geometric coordinates on the strip, and - an electronic module housed in a compartment of the base (1), comprising: means for collecting the electrical signals generated by said sensors and recording for each sensor the value of the pressure undergone associated with the position of said sensor, means for determining the area (7) of each foot on the dedicated location (5, 6) of the platform (3) and for defining three ranges of said area corresponding to three areas of underlying sensors, means for determining the pressure exerted on a given area, and the contribution of said pressure to the total pressure exerted on the right-of-way (7), and - Means for comparing the contribution of the pressure exerted in each zone with a theoretical contribution calculated according to a predefined distribution key, in order to determine the type of plantar support of said person. Device according to claim 1, characterized in that each set of sensors comprises from 50 to 100 sensors, each set being arranged in two networks occupying at least the distal part and the proximal part of the strip on which they are arranged. Device according to either of Claims 1 and 2, characterized in that the sensors are chosen from capacitive type force sensors, [Claim 4] [Claim 5] [Claim 6] [Claim 7] [Claim 8] [ Claim 9] piezoelectric type force sensors or force sensing resistors. Device according to one of the preceding claims, characterized in that the plate (3) of the cover (2) and the upper surface of the base (1) are placed at a spacing of 0.5 mm to 1 mm. Device according to one of the preceding claims, characterized in that the cover (1) is covered with a shell of a material capable of being deformed under the effect of plantar pressure to conform to the relief. Device according to the preceding claim, characterized in that said shell with a thickness of between 5 mm and 10 mm, is removable and envelops the plate (3) and the lateral flanges (4) of said cover. Device according to one of the preceding claims, characterized in that it comprises one or more of the following means: - means to indicate that a step of activating the measurement functions is in progress, - means to invite the person to place their feet on the dedicated locations (5,6), means for viewing the course of the determination, and - Means for displaying the result of the determination. Device according to one of the preceding claims, characterized in that it comprises autonomous means for supplying electrical energy. Method for determining the type of plantar support of a person using a device according to one of the preceding claims, said person standing, left foot and right foot placed respectively on the two locations (5 , 6) dedicated that comprises the plate (3), characterized in that it comprises the steps consisting in: a) - activate the measuring functions of the device, b) - collecting the electrical signals delivered by the sensors and recording for each sensor the value of the pressure undergone associated with the position of said sensor, c) - for each leg, determine the area (7) on the dedicated location of the plate (3) and define three areas of said area corresponding to three areas of underlying sensors, d) - for each sensor zone, determine the pressure exerted on said zone and the contribution of said pressure to the total pressure exerted by the right-of-way, e) - for each zone, compare the contribution of the pressure of 17 [Claim 10] [Claim 11] [Claim 12] [Claim 13] [Claim 14] [Claim 15] [Claim 16] completed in d) with a theoretical contribution calculated according to a predefined distribution key, and f) use the result of said comparison to determine the type of plantar support of said person. Method according to the preceding claim, characterized in that, in step c), the non-zero values of the pressure are selected with the geometric coordinates of the requested sensors, the set of these coordinates defining the foot area of the individual. Method according to the preceding claim, characterized in that, in step c), the plantar area is divided into three areas, namely two front areas, one of which is external PI and the other internal is P2, and a rear area P3, corresponding respectively to three zones of underlying sensors Z1, Z2, Z3. Method according to the preceding claim, characterized in that, in step d), one searches in each of the zones Z1, Z2, Z3, for the sensor subjected to the maximum pressure to which the status of master sensor C1, C2, C3 is assigned; a support area A1, A2, A3 including said master sensor and a series of peripheral sensors is defined in the vicinity of each master sensor, and the sum of the pressures undergone by the sensors belonging to said support area is calculated. Method according to claim 12, characterized in that each of the support zones A1, A2, A3 comprises the sensors situated within a predefined radius around the master sensor C1, C2, C3. Method according to one of claims 12 or 13, characterized in that, in step d), the contribution of each support zone Al, A2, A3 is calculated relative to the sum of the pressures undergone by the sensors applied by the right-of-way (7). Method according to one of claims 12 to 15, characterized in that, in step e), the pressure distribution key used to calculate the theoretical contribution of the pressure on each support zone A1, A2, A3 is defined as affecting 2/3 of the total pressure at the rear support zone A3, and 1/6 at each of the external front support zones A1 and internal A2. Method according to claim 14 or 15, characterized in that, in step f), the difference E% observed between the measured and theoretical contributions is calculated and said difference is used to determine the type of plantar support of said person as follows: - if the pressure recorded on the external front support zone is greater [Claim 17] by more than E% than the value of the theoretical contribution, the support is of the supinator type, - if the pressure recorded on the internal front support zone is more than E% greater than the value of the theoretical contribution, the support is of the pronator type, - if neither of these two conditions is met, the support is of the universal type. Method according to the preceding claim, characterized in that steps b) to d) are repeated at least N times, N being at least equal to 5, preferably at least 10, and more preferably at least 30, to determine N values of the pressure exerted on said support zone, and the average of the N values is used to determine the contribution of said pressure to the total pressure exerted by the right-of-way (7).