FR3072016A1 - SYSTEM FOR DIRECT MEASUREMENT OF A WEIGHT APPLIED BY A PATIENT ON HIS FOOT - Google Patents

Abstract

The present invention relates to a system (1) for direct measurement of a weight applied by a patient to his foot, the system (1) comprising: a sole (20) provided to receive the foot in support; at least one force sensor (30) integrated with the sole (20); a treatment unit (40) calculating a weight value applied by the patient to his foot from measurements made by the at least one force sensor (30); and a human-machine interface informing the live patient of the weight value calculated by the processing unit (40).

Description

Live measurement system of a weight applied by a patient on his foot

The present invention relates to a system for direct measurement of a weight applied by a patient to his foot.

The field of the invention is that of baropodometry systems, used in particular for the rehabilitation of patients following an injury to the lower limbs, or any neurological problem causing loss of sensitivity of the lower limbs.

In this field, an “Alter-G” system is known, comprising a treadmill and a gravity reduction chamber. This system is described in particular in document US2011098615A1. However, this system is complex and expensive, so that it is generally reserved for top athletes and is not accessible to the greatest number.

The object of the present invention is to provide a simple, practical and efficient system.

To this end, the subject of the invention is a system for direct measurement of a weight applied by a patient to his foot, the system comprising:

a sole provided to receive the foot in support;

at least one force sensor integrated into the sole;

a processing unit calculating a value of weight applied by the patient to his foot from measurements made by at least one force sensor; and a human-machine interface informing the patient directly of the weight value calculated by the treatment unit.

Thus, the invention makes it possible to measure the baropodometry of the patient directly, in a simple and practical manner. The system is inexpensive, while offering high measurement reactivity and low energy consumption.

According to other advantageous characteristics of the invention, taken individually or in combination:

- The system includes a device for adjusting the signals supplied by the man-machine interface according to the calculated weight value.

- At least one force sensor is a strain gauge.

- The system comprises three force sensors, including a first sensor disposed in a rear part of the sole, a second sensor disposed in a central part of the sole, and a third sensor disposed in a front part of the sole.

- At least one force sensor is connected to a Wheatstone bridge also integrated into the sole.

- The man-machine interface emits a visual signal by displaying the weight value on a screen.

- The human-machine interface emits a visual signal in the form of light signals.

- The man-machine interface beeps.

- The human-machine interface emits a tactile signal in the form of vibrations.

- At least two ranges of value are defined within the processing unit with respect to a set value. The signals provided by the human-machine interface depend on the value range where the calculated weight value is located.

- Two value ranges are defined, on either side of the setpoint.

- Three value ranges are defined in relation to the set value.

- Four value ranges are defined in relation to the setpoint.

- The adjustment device modifies the setpoint, and therefore the signals provided by the man-machine interface according to the calculated weight value.

- The adjustment device is offset away from the sole.

- The man-machine interface is remote from the sole.

- The adjustment device and the man-machine interface are integrated into the same device.

- The system includes a mobile terminal which is provided with a dedicated application and which integrates at least the human-machine interface.

- The mobile terminal integrates the man-machine interface and the adjustment device, within the dedicated application.

The invention will be better understood on reading the description which follows, given solely by way of nonlimiting example and made with reference to the appended drawings in which:

Figure 1 is a schematic representation of a patient equipped with a system according to the invention;

Figure 2 is a schematic representation of a femur bone with a transverse fracture;

Figures 3 and 4 are top views of a system according to the invention;

Figure 5 is a block diagram illustrating the operation of the system of Figures 3 and 4; and Figures 6, 7 and 8 are front views of a mobile terminal, showing different screens on an application dedicated to the system.

In Figure 1 is shown a patient 2 equipped with crutches 8, due to an injury of one or more lower limbs.

For example, as shown in Figure 2, patient 2 may have had a transverse fracture 5 of the femur 4.

Patient 2 has at least one foot 3 equipped with a system 1 according to the invention, designed to measure directly a weight P applied by patient 2 to this foot 3. In other words, system 1 makes it possible to measure patient baropodometry 2.

Depending on the needs, patient 2 can have a single foot 3 or each foot 3 equipped with a system 1.

The system 1 makes it possible in particular to detect whether the support on the foot 3 is satisfactory, or too great, when the patient 2 places this foot 3 on the ground. Thus, patient 2 can adapt his approach in order to promote his healing. In particular, practitioners have found that the support of foot 3 on the ground can be beneficial for healing, compared to the lack of support, to some extent.

In Figures 3 to 5 is shown an embodiment of the system 1 according to the invention, corresponds to a prototype. The system 1 can have different constructions without departing from the scope of the invention.

The system 1 comprises an article of footwear 10 provided with a sole 20, force sensors 30 integrated into the sole 20, a processing unit 40, a man-machine interface 50 and an adjustment device 60.

In the example of the figures, the footwear 10 is a sandal comprising a flexible upper part 12 secured to the sole 20. The part 12 is provided to cover the foot 3 equipped with the article 10. The part 12 comprises straps 14 for its opening and closing. A sandal has the advantage of being easy to put on and take off, especially for patient 2 during rehabilitation.

Alternatively, the footwear 10 can be of any type without departing from the scope of the invention.

The sole 20 has a rear part 21 at the heel, a central part 22 at the arch, and a front part 23 at the phalanxes. The sensors 30 are distributed in the different parts 21, 22 and 23, as detailed below.

The sole 20 has an upper layer 24 and a lower layer 25. The upper part 12 of article 10 is integral with the lower layer 25. The sensors 30 are housed in the lower layer 25. The upper layer 24 is removable with respect to to the lower layer 25, to cover or uncover the sensors 30. The upper layer 24 is thinner than the lower layer 25.

The force sensors 30 are designed to each measure a value of force, exerted by the foot 3 pressing on the sole 20.

The force sensors 30 are preferably strain gauges, housed in the lower layer 25 of the sole 20. Pressing the foot 3 on the sole 20 urges the gauges in compression, in a vertical direction. Strain gauges have many advantages: small deformations and therefore resistance over time, calibration accuracy, measurement accuracy, high compactness, reduced cost.

Alternatively, the force sensors 30 can be constructed differently without departing from the scope of the invention. The force sensors 30 are distinct from the pressure sensors, in particular with regard to the physical quantities measured and the technologies implemented for this purpose.

Advantageously, the system 1 comprises three force sensors 30, including a first sensor 31 disposed in the rear part 21 of the sole 20, a second sensor 32 disposed in the central part 22 of the sole 20, and a third sensor 33 disposed in the front part 23 of the sole 20. This improves the precision of calculation of the weight P exerted on the foot 3.

Alternatively, the system 1 may comprise a single sensor 30, preferably arranged in part 21, at the heel. According to other alternatives, the system 1 can comprise two sensors 30, or more than three sensors 30.

The processing unit 40 is designed to calculate a weight value P applied by the patient 2 to his foot 3, from the measurements made by the force sensors 30.

Unit 40 includes three Wheatstone bridges 41, 42 and 43, three operational amplifiers 44, 45 and 46, an analog-digital converter 47, a microcontroller 48 and a tare 49. Bridges 41, 42 and 43 are connected respectively sensors 31, 32 and 33 on the one hand, and amplifiers 44, 45 and 46 on the other.

Advantageously, the bridges 41-43 can be integrated into the sole 20, in the layer 25, each next to the corresponding gauge 31-33. Preferably, the layer 25 comprises a cavity for each of the elements 31-33 and 41-43. Electrical wires extend through layer 25, between the different cavities, and up to amplifiers 44-46.

Each bridge 41-43 makes it possible to measure the variations in electrical resistance in the corresponding gauge 31-33. These analog variations are amplified by amplifiers 44-46, converted to digital by converter 47, and analyzed by microcontroller 48 to calculate the weight value P applied by patient 2 on his foot 3.

The microcontroller 48 is configured to perform a comparison calculation of the weight value P calculated with a set value. This set value can be adjusted by the adjustment device 60, in this case a potentiometer 61. Depending on the results of the calculation, the microcontroller 48 activates the man-machine interface 50 in a certain way, as detailed below. after. The adjustment device 60 makes it possible to adapt the signals supplied by the interface 50 as a function of the weight value P calculated by the unit 40.

The tare 49 makes it possible to reset the unit 40, when no support is exerted on the sole 20.

By way of example, the scale for measuring the weight P exerted by the patient 2 on his foot 3 can be from 5 to 100 kg, with an accuracy of 1 to 2 kg.

The man-machine interface 50 constitutes an indicator device essential to the functioning of the invention. The interface 50 makes it possible to inform the patient 2 directly of the weight value P calculated by the processing unit 40. To this end, the interface 50 can emit visual, sound and / or tactile signals.

In the example of the figures, the interface 50 comprises two light-emitting diodes 51 and 52 of different colors, for example green and red, as well as an audible warning 53.

The potentiometer 61 makes it possible to set a setpoint not to be exceeded. Different predetermined value ranges are defined within the processing unit 40 with respect to this set value. The aim is that the signals supplied by the man-machine interface 50 vary directly as a function of the range of values in which the weight value P is calculated calculated by the unit 40.

For example, for a particular patient 2, a setpoint of 20 kg is set, with a range of 18 to 20 kg, a range of 16 to 18 kg, and a range of less than 16 kg. When the weight P calculated by the unit 40 is less than 16kg, the interface does not transmit any particular signal. When the weight P is between 16 and 18 kg, the green diode 51 lights up, indicating that the weight P is satisfactory. When the weight P is between 18 and 20 kg, the red diode 52 lights up, indicating that the weight P is slightly too high. When the weight P is greater than 20 kg, the alarm 53 emits a noise while the red diode 52 indicates that the weight P is too high at a level detrimental to healing.

Thus, patient 2 can adapt his approach in order to promote his healing.

The system 1 also includes energy supply means, not shown for the purpose of simplification. By way of nonlimiting example, these supply means can be constituted by a flat battery. System 1 has the advantage of low energy consumption.

In FIGS. 6 to 8 is shown a mobile terminal 70, of the smart phone type (“smartphone” in English), comprising an application dedicated to the system 1. This application makes it possible to implement a rehabilitation program adapted to the patient 2.

FIG. 6 shows the adjustment of a set value, directly on the screen of the terminal 70 constituting the adjustment device 60, as well as the adjustment of an exercise time

FIG. 7 shows a bar 54 having different colors (green, orange, red), corresponding to different ranges of weight values P calculated by the unit 40. The screen of the terminal 70 thus constitutes the man-machine interface 50, emitting a visual signal. In addition, a loudspeaker of the terminal 70 can emit an audible signal.

Figure 8 shows a session report including the number of cycles, the elapsed time, the maximum weight P calculated.

Furthermore, the system 1 can be shaped differently from Figures 1 to 8 without departing from the scope of the invention.

In a variant not shown, the man-machine interface 50 can emit a tactile signal, in the form of vibrations transmitted to the patient 2.

According to another variant not shown, the adjustment device 60 can be fixed to the wrist, to the belt, or to a crutch. The same is true for the man10 machine interface 50.

According to another variant, not shown, the application installed on the terminal 70 can implement other parameters.

In addition, the technical characteristics of the various embodiments and variants mentioned above may be, in whole or for some of them, combined with one another. Thus, the system 1 can be adapted in terms of cost, functionalities and performance.

Claims (11)

1. System (1) for direct measurement of a weight (P) applied by a patient (2) to his foot (3), the system (1) comprising: - a sole (20) provided to receive the foot (3) in support; - at least one force sensor (30) integrated into the sole (20); - a processing unit (40) calculating a weight value (P) applied by the patient (2) to his foot (3) from measurements made by the at least one force sensor (30); a man-machine interface (50) informing the patient (2) directly of the weight value (P) calculated by the processing unit (40). 2. System (1) according to the preceding claim, characterized in that it comprises a device (60) for adjusting the signals supplied by the man-machine interface (50) as a function of the calculated weight value (P). 3. System (1) according to one of the preceding claims, characterized in that it comprises three force sensors (30), including a first sensor (31) disposed in a rear part (21) of the sole (20) , a second sensor (32) arranged in a central part (22) of the sole (20), and a third sensor (33) disposed in a front part (23) of the sole (20). 4. System (1) according to one of the preceding claims, characterized in that the at least one force sensor (30) is connected to a Wheatstone bridge (41, 42, 43) also integrated into the sole (20 ). 5. System (1) according to one of the preceding claims, characterized in that the man-machine interface (50) is configured to emit a visual signal by displaying the weight value (P) on a screen. 6. System (1) according to one of the preceding claims, characterized in that the man-machine interface (50) is configured to emit a visual signal in the form of light signals. 7. System (1) according to one of the preceding claims, characterized in that the man-machine interface (50) is configured to emit an audible signal. 8. System (1) according to one of the preceding claims, characterized in that 5 the human-machine interface (50) is configured to emit a tactile signal in the form of vibrations. 9. System (1) according to one of the preceding claims, characterized in that at least two value ranges are defined within the processing unit (40) by 10 relative to a set value, and in that the signals supplied by the man-machine interface (50) depend on the range of values where the calculated weight value (P) is found. 10. System (1) according to one of the preceding claims, characterized in that it 15 comprises a mobile terminal (70) which is provided with a dedicated application and which integrates at least the man-machine interface (50). 1/4