WO2024117589A1 - Pressure sensor mounted inside femoral prosthesis socket and manufacturing method for pressure sensor, and walking intention estimation device and walking intention estimation method using same - Google Patents

Abstract

According to the present invention, a walking intention estimation device using a pressure sensor mounted inside a femoral prosthesis socket comprises: a pressure value acquisition unit for acquiring respective pressure values from a plurality of pressure sensors provided inside the socket; a pressure change analysis unit for analyzing a pressure change by comparing the pressure value acquired at the current point of time and an initial pressure value; and an estimation unit for estimating the walking intention of a user by using a pressure change pattern of the plurality of pressure values, if it is determined that a pressure change has occurred. According to the present invention, a film-type sensor is used, and thus is suitable for the physical characteristics of a cut portion, is not affected by temperature and humidity conditions inside the socket, and is easily manufactured in various sizes.

Description

A pressure sensor mounted inside a femoral prosthesis socket and a method of manufacturing the pressure sensor, a walking intention estimation device and a walking intention estimation method using the same

The present invention relates to a pressure sensor mounted inside a femoral prosthesis socket, a method of manufacturing the pressure sensor, a walking intention estimation device and a walking intention estimation method using the same, and more specifically, it is not vulnerable to noise due to body impedance and the film The present invention relates to a pressure sensor mounted inside a femoral prosthesis socket that is flexible in shape and capable of responding to body bending patterns, and a method of manufacturing the pressure sensor, as well as a walking intention estimation device and a walking intention estimation method using the same.

In general, a femoral prosthesis is an assistive device that replaces the function of the lower extremity above the knee joint that has been lost due to accidents or diseases.

Femoral prosthetics started out as a passive prosthesis in the past and has developed into an active prosthesis that generates and provides the necessary walking trajectory through an actuator.

Active prosthetics support various walking functions, such as walking on level ground, walking on stairs, sitting, and standing.

However, each functional movement provided by the prosthetic leg has no similarity to the walking sequence.

Therefore, prosthetics must be changed to an appropriate control method to suit each walking environment.

In the past, a manual method was used in which the prosthetic leg user directly judged when a change was necessary and made the change.

However, prosthetic leg users feel unnatural during the manual change process, and demand prosthetic legs that allow for more natural changes.

In response to these demands, research is being conducted to change the walking method by determining the user's intention to change control within the prosthetic limb.

Conventionally, the purpose was to detect the user's walking intention by measuring the pressure inside the socket that is in direct contact with the femoral amputation site.

The pressure change inside the socket is a biomechanical characteristic that occurs when the distributed weight of the prosthetic leg is concentrated at a specific point due to the movement of the lower extremity, causing the location of the load application point to change.

The location and aspect of the load application point detected by measuring the pressure change within the socket indicate the user's intentional hip joint movement.

Therefore, prior technologies attempted to determine the location of the load application point inside the socket by measuring the pressure change within the socket using a capacitance-type pressure sensor or a resistance change-type pressure sensor.

However, capacitive pressure sensors are vulnerable to noise caused by skin impedance that changes as the temperature inside the socket rises and sweat occurs.

Additionally, in the case of commercial sensors, the reproducibility of sensor data is low due to the shape and attachment that do not take into account the curvature of the body, and there is a problem of causing injury to the skin inside the socket.

In addition, since 1990, electronically controlled prosthetics have been researched and developed to more closely imitate the walking movements of non-amputees, and are currently capable of imitating not only simple walking functions but also various daily life movements.

However, in response to the discontinuous walking environment, there was a problem in that it was difficult for the prosthetic limb to respond flexibly on its own when it was necessary to change to a walking method suitable for the environment.

Therefore, conventionally, in order to change the walking mode, a method of changing the walking mode through external operating equipment or an application is trusted. However, prosthetic leg wearers complain of discomfort due to the burden of carrying an external device and the unnaturalness that occurs in the process of taking out and operating the external device.

In response to these demands, research has recently been conducted to detect the intention to change walking mode using electromyography sensors. The electromyography sensor is a sensor that detects electrical signals that change according to muscle movement, and was able to achieve the effect of changing the walking mode through muscle movement without external manipulation equipment.

However, there was a problem in that a clear EMG signal could not be detected when skin extension surgery or artificial skin was implanted at the amputation site where the EMG sensor was attached, or when muscle fatigue was accumulated due to long-term activity.

For prior art, please refer to Republic of Korea Patent Publication No. 10-2021-0064975 (2021.06.03) and Republic of Korea Patent Publication No. 10-2020-0006833 (2020.01.21).

The present invention is relatively resistant to noise caused by the increase in temperature inside the socket and the skin impedance that changes with sweat, and has a flexible form that does not cause injury to the area where the femoral prosthesis socket is worn, and does not cause injury to the body or the femoral prosthetic socket. A pressure sensor mounted inside the femoral prosthesis socket that provides a pressure sensor that does not cause lifting due to bending as it responds to the internal bending pattern, and estimates the intention to change the walking mode using the pressure change obtained from the pressure sensor, and The purpose is to provide a manufacturing method for the pressure sensor, a walking intention estimation device and a walking intention estimation method using the same.

The pressure sensor mounted inside the femoral prosthetic leg socket according to the present invention relates to a pressure sensor mounted inside the femoral prosthetic leg socket. The sensor body includes a first electrode plate on a rectangular plate; A Velostat film laminated on the upper side of the first electrode plate in the form of a square plate; A second electrode plate, in the form of a rectangular plate, laminated on the upper side of the velostat film; a first insulating film laminated on the lower side of the first electrode plate to insulate the lower side of the sensor body; and a second insulating film laminated on the upper side of the second electrode plate to insulate the upper side of the sensor body.

At this time, the incision according to the present invention is preferably formed in a triangular shape.

And the cutout according to the present invention is preferably formed at the center of the outer periphery of the sensor body on a rectangular plate.

In addition, the incisions according to the present invention are formed on the front, rear, left, and right outer peripheries of the sensor body on the rectangular plate, forming four incisions.

The method of manufacturing a pressure sensor mounted inside a femoral prosthetic leg socket according to the present invention includes the steps of a) determining the internal curvature of the area where the pressure sensor is to be provided among the interior of the femoral prosthetic leg socket; b) preparing a first electrode plate and a second electrode plate on a rectangular plate having the same area; c) Preparing a Velostat film; d) manufacturing a sensor body by laminating a first electrode plate and a second electrode plate on the upper and lower sides of the Velostat film, respectively, with the Velostat film interposed therebetween; e) It includes the step of cutting so that an incision of the corresponding size is formed in the sensor body in response to the internal bending pattern of the corresponding prosthetic femoral leg socket.

A walking intention estimation device using a pressure sensor mounted inside a femoral prosthetic leg socket according to the present invention includes a pressure value acquisition unit that acquires respective pressure values from a plurality of pressure sensors installed inside the femoral prosthetic leg socket; a pressure change analysis unit that analyzes the pressure change by comparing the pressure value obtained at the current time and the initial pressure value; and an estimation unit that, when it is determined that a pressure change has occurred, estimates the user's walking intention using a pressure change pattern of a plurality of pressure values.

At this time, the pressure sensor according to the present invention is preferably installed inside the femoral prosthesis socket so as to correspond to the front part of the user's thigh, the rear part of the thigh, and the bottom of the cut part.

Here, a plurality of pressure sensors according to the present invention may be installed vertically on the inner front part of the femoral prosthetic leg socket, and one each may be installed on the inner bottom and inner rear of the femoral prosthetic leg socket.

In addition, the pressure change analysis unit according to the present invention sets each pressure value measured immediately before the user performs a specific operation as an initial pressure value and analyzes whether there is a change from the set initial pressure value.

Additionally, the estimation unit according to the present invention estimates at least one walking intention among walking on level ground, climbing or descending stairs, stopping, sitting, and standing.

A method of estimating walking intention using a walking intention estimating device according to the present invention includes obtaining respective pressure values from a plurality of pressure sensors installed inside a prosthetic femoral leg socket; analyzing pressure changes by comparing the pressure value obtained at the current point in time with the initial pressure value; and, when it is determined that a pressure change has occurred, estimating the user's walking intention using the pressure change pattern of a plurality of pressure values.

At this time, the pressure sensor according to the present invention is preferably installed inside the femoral prosthesis socket so as to correspond to the front part of the user's thigh, the rear part of the thigh, and the bottom of the cut part.

Here, a plurality of pressure sensors according to the present invention are installed vertically on the inner front part of the femoral prosthetic leg socket, and one each is installed on the inner bottom and inner rear of the femoral prosthetic leg socket.

In the step of analyzing the pressure change according to the present invention, each pressure value measured immediately before the user performs a specific action is set as an initial pressure value, and whether there is a change from the set initial pressure value is analyzed.

Additionally, the step of estimating the walking intention according to the present invention estimates at least one walking intention among walking on level ground, going up or down stairs, stopping, sitting, and standing.

The effects of the pressure sensor mounted inside the femoral prosthesis socket and the manufacturing method of the pressure sensor according to the present invention, and the walking intention estimation device and walking intention estimation method using the same are as follows.

Inside the femoral prosthetic socket, it is relatively resistant to noise caused by the increase in temperature inside the socket and skin impedance that changes with sweating, and its flexible form does not cause injury to the area where the femoral prosthetic socket is worn, and the bending pattern inside the femoral prosthetic socket or the body As it responds to , the phenomenon of lifting due to bending does not occur.

Since it uses a film-type sensor, it is suitable for the physical characteristics of the cut area, is not affected by the temperature and humidity conditions inside the socket, and has the effect of being easy to manufacture in various sizes.

Figure 1 is an exemplary diagram showing the stacking process of a pressure sensor mounted inside a femoral prosthesis socket according to an embodiment of the present invention.

Figure 2 is an exemplary diagram showing a pressure sensor mounted inside a femoral prosthesis socket according to an embodiment of the present invention.

Figure 3 is an exemplary diagram showing a state in which a pressure sensor according to an embodiment of the present invention is mounted inside a femoral prosthetic leg socket.

Figure 4

Figure 5 is a graph showing the initial output values of five pressure sensors according to an embodiment of the present invention.

Figure 6 is a graph showing pressure measurement characteristics according to the difference in cutting amount of the pressure sensor according to an embodiment of the present invention.

Figure 7 is an exemplary diagram showing a walking intention estimation device using a pressure sensor according to an embodiment of the present invention.

Figure 8 is a graph showing output distribution according to pressure application for each sensor size.

Figure 9 is an example diagram for explaining the location of a pressure sensor installed in a femoral prosthesis socket.

Figure 10 is a configuration diagram for explaining a walking intention estimation device according to an embodiment of the present invention.

Figure 11 is a flowchart for explaining a method of estimating walking intention using a walking intention estimating device according to an embodiment of the present invention.

Figure 12 is an exemplary diagram showing the force of pressure acting inside the femoral prosthesis socket.

Figure 13 is an example diagram showing changes in the user's walking in step S520 shown in Figure 11.

Figures 14 to 18 are graphs showing pressure values measured according to changes in walking shown in Figure 13.

The present invention relates to a pressure sensor mounted inside a femoral prosthesis socket, wherein the sensor body includes a first electrode plate on a square plate; A Velostat film laminated on the upper side of the first electrode plate in the form of a square plate; A second electrode plate, in the form of a rectangular plate, laminated on the upper side of the velostat film; a first insulating film laminated on the lower side of the first electrode plate to insulate the lower side of the sensor body; and a second insulating film laminated on the upper side of the second electrode plate to insulate the upper side of the sensor body.

The present invention includes the steps of a) determining the internal curvature of the area where the pressure sensor is to be provided among the interior of the prosthetic leg socket; b) preparing a first electrode plate and a second electrode plate on a rectangular plate having the same area; c) Preparing a Velostat film; d) manufacturing a sensor body by laminating a first electrode plate and a second electrode plate on the upper and lower sides of the Velostat film, respectively, with the Velostat film interposed therebetween; e) A method of manufacturing a pressure sensor mounted inside a femoral prosthetic leg socket is provided, including the step of cutting the sensor body so that an incision of the corresponding size is formed in response to the internal curvature of the prosthetic leg socket.

The present invention includes a pressure value acquisition unit that acquires each pressure value from a plurality of pressure sensors installed inside the socket; a pressure change analysis unit that analyzes the pressure change by comparing the pressure value obtained at the current time and the initial pressure value; and an estimation unit that estimates the user's walking intention using a pressure change pattern of a plurality of pressure values when it is determined that a pressure change has occurred. A walking intention estimation device using a pressure sensor mounted inside a femoral prosthesis socket is provided. .

The present invention includes the steps of obtaining each pressure value from a plurality of pressure sensors installed inside the socket; analyzing pressure changes by comparing the pressure value obtained at the current point in time with the initial pressure value; and, when it is determined that a pressure change has occurred, estimating the user's walking intention using a pressure change pattern of a plurality of pressure values.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the attached drawings. Prior to this, the terms or words used in this specification and claims should not be construed as limited to their usual or dictionary meanings, and the inventor should appropriately define the concept of terms in order to explain his or her invention in the best way. Based on the principle of definability, it must be interpreted with meaning and concept consistent with the technical idea of the present invention.

Therefore, the embodiments described in this specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention, and do not represent the entire technical idea of the present invention, so at the time of filing this application, they can be replaced by equivalent equivalents. It should be understood that variations may exist.

The present invention consists of a pressure sensor mounted inside the femoral prosthetic leg socket as a film-type resistance change type pressure sensor, which is relatively resistant to noise caused by the temperature rise inside the socket and the skin impedance that changes with sweat. The strong, flexible form does not cause injury to the socket wearing area, making it advantageous for application inside the socket. A pressure sensor mounted inside a femoral prosthetic socket capable of responding to the curvature of the body or inside the femoral prosthetic socket, and a method of manufacturing the pressure sensor. Regarding this, if you look at it with reference to the drawings, it is as follows.

The pressure sensor 100 mounted inside the femoral prosthetic leg socket 1 according to an embodiment of the present invention with reference to FIGS. 1 to 3 is mounted inside the femoral prosthetic leg socket 1, and the sensor body 10 is It includes a first electrode plate (11), a Velostat film (12), a second electrode plate (13), a first insulating film (14), and a second insulating film (15).

The first electrode plate 11 is preferably made of a conductive metal such as copper, gold, silver, or aluminum and has a square plate shape with the horizontal and vertical sides being the same length.

At this time, it is preferable that the first electrode plate 11 and the second electrode plate 13 have the same material, shape, and area.

And the Velostat film 12 is also laminated on the upper side of the first electrode plate 11 in the form of a square plate.

At this time, the Velostat film 12 is not vulnerable to noise due to body impedance, has a variable resistance type in which the electrical resistance changes depending on the pressure applied to the plane, and is flexible in the form of a thin film.

Therefore, the Velostat film 12 can be easily manufactured in various sizes and shapes, so it can be molded taking into account the curvature of the body and the socket 1, thereby preventing lifting.

The area of the Velostat film 12 is preferably relatively larger than that of the first electrode plate 11 and the second electrode plate 13, which have the same area, and the first electrode plate 12 After applying adhesive to the upper side of the Velostat film (11), it is integrally joined so that the first electrode plate (11) is located at the center of the lower area of the Velostat film (12).

And a second electrode plate 13 is laminated on the upper side of the velostat film 12. The second electrode plate 13 is also made of copper, gold, and silver, which are conductors, like the first electrode plate 11. , A rectangular plate shape is made of a metal material such as aluminum, and adhesive is applied to the lower side of the second electrode plate 13, and then the second electrode is placed at the center of the upper area of the Velostat film 12. It is integrally joined so that the plate 13 is positioned.

Therefore, by the above-described structure, the Velostat film 12 is placed at the center, and the first electrode plate 11 and the second electrode are placed on the upper and lower sides of the Velostat film 12. It forms a sandwich structure in which the plates 13 are each stacked.

In addition, a first insulating film 14 is bonded to the lower side of the first electrode plate 11 to insulate the lower side of the sensor body 10, and a first insulating film 14 is attached to the upper side of the second electrode plate 12. 2. The insulating film 15 is bonded to insulate the upper side of the sensor body 10.

At this time, the first insulating film 14 and the second insulating film 15 are formed to have an area equal to that of the Velostat film 12, or are formed to have an area larger than the area of the Velostat film 12. It is desirable to form it to have a relatively large area.

Here, the pressure sensor 100 mounted inside the femoral prosthesis socket 1 according to an embodiment of the present invention is the Velostat (Velostat) to enable confirmation of the amount of pressure application through measurement of the electrical resistance that changes when pressure is applied. ) The first electrode plate 11 and the second electrode plate 12 are stacked on both the upper and lower sides of the film 12 to form a sandwich shape, and the circuit of the pressure sensor 100 is composed of a Wheatstone bridge. , the lead wires of the first electrode plate 11 and the second electrode plate 12 are configured as a circuit arranged in a position close to the applied power source, so that the amount of pressure can be measured in the form of a rising voltage when pressure is applied.

The internal reference resistance of the circuit described above is specified to generate an initial output of 500 mV in a pressure-free state, and the amount of applied pressure can be measured through the increasing output voltage value.

A plurality of incisions 20 are formed on the outside of the sensor body 10 of the above-described configuration to correspond to the inner curved surface of the prosthetic femoral leg socket 1.

Since the femoral prosthetic leg socket (1) is structured to surround the amputated lower extremity, there is a bend, and the pressure sensor (100) attached inside the femoral prosthetic leg socket (1) does not adhere closely to the surface of the femoral prosthetic leg socket (1), causing a lifting phenomenon. In addition, the lifting of the pressure sensor causes deformation of the sensor shape such as crumpling, lowering the reproducibility of sensor data.

Therefore, the pressure sensor 100 mounted inside the femoral prosthesis socket 1 according to an embodiment of the present invention can solve this problem by forming a plurality of incisions 20 in the sensor body 10. .

The incision 20 is formed in a triangular shape, preferably an isosceles triangle with a base at the outer periphery of the sensor body 10 and a height toward the center of the sensor body 10.

At this time, the incisions 20 are formed around the outer periphery of the sensor body 10 on a square plate in the front, rear, left, and right directions, forming four incisions 20, and each incision 20 is preferably formed at the center of the outer periphery of the sensor body 10, which has a rectangular plate shape.

In addition, the amount of cutting of the sensor body 10 to form the incision 20 can be adjusted by varying the ratio of the base and height of the triangle, provided that no lifting occurs at the inner bending portion of the femoral prosthetic leg socket 1. In order to minimize the cutting area at the same time, various sensors were prepared and confirmed as shown in Figure 4 below.

The excitation phenomenon of each pressure sensor according to FIG. 4 can be confirmed through the initial output value of the pressure sensor. The initial output value when pressure is not applied is 500 mV set through the internal reference resistance, and the initial output value exceeding 500 mV is the resistance of the sensor. This is the result of a decrease in ingredients. Therefore, if the initial output value exceeds 500mV, it can be seen that the sensor is bent and crumpled due to the lifting phenomenon.

Figure 3 shows the state of installing the pressure sensor inside the femoral prosthetic leg socket (1). The attachment position is located at a large bend inside the femoral prosthetic leg socket (1) in order to check the degree of lifting of the pressure sensor (100) according to the amount of cutting. It was designated as the lower part where this exists.

FIG. 5 is a graph showing the initial output values of the five pressure sensors shown in FIG. 4. Referring to FIG. 5, the degree of lifting of the pressure sensor according to the amount of cutting is confirmed by comparing the output values before and after attachment to the inside of the femoral prosthesis socket (1). It is possible, and pressure sensor number 1, which was not cut, measured the highest initial output value after applying the femoral prosthesis socket (1) compared to the other four pressure sensors.

In comparison, the initial output values of the remaining four pressure sensors tend to decrease as the cutting amount increases, and among these, sensor number 5, which has the largest cutting amount, is measured with an output value close to 500mV, making it an ideal pressure sensor that improves the lifting problem. Therefore, the lifting problem of the pressure sensor can be improved by adjusting the cutting amount.

Pressure sensor number 2 is a sensor cut into a simple straight line without a triangular base. Sensor No. 2 showed a high initial output value even though it was cut at a high level of 30% of the length, and this shows that the length of the base of the cutting triangle is essential to eliminate the lifting phenomenon.

However, if the bottom is cut excessively, the loss of the pressure sensor increases, so as shown in [Table 1], the bottom of the cut was fixed to 3 mm, which is 5% of the 60 mm on one side of the pressure sensor, and the cut size was adjusted by only changing the cut height. .

Referring to FIG. 6, pressure sensor No. 1, on which cutting was not performed, shows the highest initial output value compared to the three pressure sensors on which cutting was performed. Because of this, pressure sensor No. 1 has a narrow pressure measurement range, making precise pressure measurement difficult.

The three sensors where cutting was performed show a tendency for the lifting phenomenon to decrease and the pressure measurement range to widen as the amount of cutting increases.

Through this, it can be confirmed that the foundation outside the sensor can solve the lifting phenomenon.

Pressure sensors 2 and 3 show higher initial output values and narrower measurement ranges compared to pressure sensor 4, but have the advantage of less sensor area being lost due to cutting.

Therefore, it is judged that good use is possible in areas with little curvature, and the cutting of the pressure sensor can be selectively applied as needed, taking into account the curvature pattern of the femoral prosthesis socket (1) and the area of pressure sensor loss.

A method of manufacturing a pressure sensor mounted inside a femoral prosthetic leg socket according to an embodiment of the present invention includes a) determining the internal curvature of the area where the pressure sensor is to be provided among the inside of the femoral prosthetic leg socket, and b) measuring the same area. preparing a first and second electrode plates on a rectangular plate, c) preparing a Velostat film, and d) preparing a first electrode plate with the Velostat film in between. and manufacturing a sensor body by laminating a second electrode plate on the upper and lower sides of the Velostat film, respectively, and e) making an incision of the corresponding size in the sensor body corresponding to the internal bending pattern of the corresponding femoral prosthesis socket. It includes the step of cutting to form a portion.

First, in step a), the internal curvature pattern of the area where the pressure sensor is to be provided among the interior of the femoral prosthesis socket 1 is determined.

At this time, the internal bending pattern of the femoral prosthetic leg socket 1 is 3D modeled by measuring the outer shape of the amputated limb of the wearer inserted into the femoral prosthetic leg socket 1, and the sensor body ( 10) and the size of the incision 20 to be formed in the sensor body 10 are selected.

Next, in step b), prepare the first electrode plate 11 and the second electrode plate 13 on a rectangular plate with the same area.

At this time, prepare the first electrode plate 11 and the second electrode plate 13 having an area corresponding to the size of the sensor body 10 selected in step a).

Next, in step c), prepare the Velostat film (12).

At this time, the Velostat film 12 is prepared with a relatively larger area than the areas of the first electrode plate 11 and the second electrode plate 13. (The Velostat film 12 is Approximately 10-20% larger area.)

Next is step d), where the first electrode plate 11 and the second electrode plate 13 are connected to the upper side of the Velostat film 12 with the Velostat film 12 in between. The sensor body 10 is manufactured by stacking each on the lower side.

At this time, after applying adhesive to each of the first electrode plate 11 and the second electrode plate 13, they are laminated so as to be integrated on the upper and lower sides of the Velostat film 12, respectively, and the first electrode plate 11 When the stacking of the electrode plate 11 and the second electrode plate 13 is completed, the first insulating film 14 and the first insulating film 14 are applied to the upper and lower surfaces of the first electrode plate 11 and the second electrode plate 13, respectively. 2 Laminate the insulating film (15).

Therefore, the sensor body 10 has the Velostat film 12 at its center, and the first electrode plate 11 and the second electrode plate 13 are positioned on the Velostat film 12. They are laminated in a sandwich structure on the upper and lower sides, respectively.

Next, in step e), the sensor body 10 is cut so that an incision 20 of a corresponding size is formed in response to the internal curvature of the femoral prosthesis socket 1.

At this time, it is preferable that the cutouts 20 are formed on the outer periphery of the sensor body 10 on the square plate in the front, rear, left, and right directions, forming four cutouts 20.

The pressure sensor 100 manufactured in this way is used by being mounted on the corresponding part inside the femoral prosthesis socket 1.

As shown in FIG. 7, the walking intention estimation device 1000 using the pressure sensor 100 according to an embodiment of the present invention obtains a pressure value from the pressure sensor 100 installed in the femoral prosthesis socket 1, The user's walking intention is estimated using the obtained pressure value.

First, explaining the pressure sensor 100, the pressure sensor 100 is an electrically conductive material mainly used as a packaging material to protect products vulnerable to static electricity and discharge. As the size of the pressure sensor 100 increases, the initial resistance value decreases, and because of this, the amount of resistance change when pressure is applied also has different characteristics depending on the size.

Figure 8 is a graph showing the output distribution according to pressure application for each pressure sensor size.

As shown in FIG. 8, when each pressure is applied to 10 pressure sensors 100 of different sizes, the pressure sensors 100 with sizes of 800㎟, 900㎟, and 1600㎟ among the 10 sensors show a linear A negative output appears.

However, for the 900 mm2 and 1600 mm2 sensors, the maximum pressure output is low at 2.7 V and reaches early saturation at 140 kPa.

In comparison, the sensor with an area of 800㎟ has a relatively high maximum pressure output of 3V, and it can be seen that it reaches saturation around 170kPa.

Therefore, if the internal pressure range of the femoral prosthesis socket 1 is 200 kPa, a sensor with a width of 20 mm, a height of 40 mm, and an area of 800 mm2 is suitable.

Once the size of the pressure sensor 100 is determined in the manner described above, the pressure sensor 100 of the determined size is cut so that it can be installed in the femoral prosthesis socket 1.

Figure 9 is an example diagram for explaining the location of a pressure sensor installed in a femoral prosthesis socket.

As shown in Figure 9, the pressure sensor 100 is installed inside the socket to correspond to the front part of the user's thigh, the rear part of the user's thigh, and the bottom of the cut part.

However, since the pressure applied to the front is greater than the pressure applied to the rear, the first pressure sensor 101 and the second pressure sensor 102 are installed on the inner front part of the femoral prosthesis socket 1.

Additionally, a third pressure sensor 103 is installed on the inner bottom of the femoral prosthesis socket 1, and a fourth pressure sensor 104 is installed on the inner rear surface.

As described above, the first pressure sensor 101, the second pressure sensor 102, the third pressure sensor 103, and the fourth pressure sensor 104 installed in the femoral prosthesis socket 1 measure the applied pressure, The measured pressure is transmitted to the walking intention estimation device 1000.

Figure 10 is a configuration diagram for explaining a walking intention estimation device according to an embodiment of the present invention.

As shown in FIG. 10, the walking intention estimation device 1000 according to an embodiment of the present invention includes a pressure value acquisition unit 1100, a pressure change analysis unit 1200, and an estimation unit 1300.

First, the pressure value acquisition unit 1100 acquires the pressure value from the pressure sensor installed in the socket.

To elaborate, the pressure value acquisition unit 1100 acquires each pressure value from the first pressure sensor 101, the second pressure sensor 102, the third pressure sensor 203, and the fourth pressure sensor 204. .

The pressure change analysis unit 1200 analyzes whether a pressure change has occurred by comparing the initial pressure value with the pressure value obtained at the current time.

To elaborate, the pressure change analysis unit 1200 sets the pressure value obtained immediately before the user assumes a specific posture as the initial pressure value, and analyzes whether a change occurs between the set initial pressure value and the pressure value obtained at the current time. .

If it is analyzed that a pressure change has occurred, the estimation unit 1300 estimates the user's walking intention using the pressure change pattern of a plurality of pressure values.

Hereinafter, a method for estimating walking intention using the walking intention estimating device 1000 according to an embodiment of the present invention will be described in more detail using FIGS. 11 to 18.

Figure 11 is a flowchart for explaining a method of estimating walking intention using a walking intention estimating device according to an embodiment of the present invention.

As shown in FIG. 11, the walking intention estimation device 1000 according to an embodiment of the present invention obtains pressure values from a plurality of pressure sensors 101, 102, 103, and 104 installed in the femoral prosthesis socket 1. (S510).

To elaborate, the pressure value acquisition unit 1100 acquires each pressure value from the first pressure sensor 101, the second pressure sensor 102, the third pressure sensor 103, and the fourth pressure sensor 104.

Next, the pressure change analysis unit 1200 analyzes the change in the obtained pressure value (S520).

First, the pressure output from the front sensor, that is, the first pressure sensor 101 and the second pressure sensor 102, and the fourth pressure sensor 104 depending on whether pressure is applied within the femoral prosthesis socket 1 according to the user's weight. ), the pressure output is different.

Figure 12 is an exemplary diagram showing the force of pressure acting inside the femoral prosthesis socket.

As shown in Figure 12, when the user stands up and the foot contacts the ground, pressure within the femoral prosthesis socket 1 is applied evenly to the front, bottom, and back.

On the other hand, as shown in FIG. 12, when the user bends the knee, that is, when the knee joint is flexed, the foot is not in contact with the ground, so the pressure within the femoral prosthesis socket 1 is concentrated on the front side.

Therefore, the pressure change analysis unit 1200 sets each pressure value measured immediately before the user performs a specific operation as the initial pressure value, and compares the pressure value measured at the current time with the initial pressure value to determine the pressure. Analyze whether there is a change.

FIG. 13 is an example diagram showing changes in the user's walking in step S520 shown in FIG. 11, and FIGS. 14 to 18 are graphs showing pressure values measured according to changes in walking shown in FIG. 13.

As shown in FIG. 13, gait changes can be classified into a standing state, a walking state on level ground, a state going up stairs, a state going down stairs, a state converted from standing to sitting, and a state converted from sitting to standing.

At this time, assuming that the user changes the walking motion from the standing state to the level walking state, the pressure change analysis unit 1200 compares the initial pressure value with the pressure value measured at the start of walking.

As a result of comparison, as shown in FIG. 14, the pressure value measured by the first pressure sensor 101 decreased by 100%, and the pressure value measured by the second pressure sensor 102 increased by 100%. Additionally, the pressure value measured by the third pressure sensor 103 decreased by 100%, and the pressure value measured by the fourth pressure sensor 104 increased by 50%.

Expressing this as a color change, the first pressure sensor 101 and the third pressure sensor 103 are expressed in blue, the second pressure sensor 102 and the fourth pressure sensor 104 are expressed in red, and the first pressure sensor 101 and the third pressure sensor 103 are expressed in red. 2 The pressure change of the input sensor 102 is higher than the pressure change of the fourth pressure sensor 104, so it is expressed in a darker color.

Additionally, assuming that the user changes the walking motion from the standing state to the stair climbing state, the pressure change analysis unit 1200 compares the initial pressure value with the pressure value measured in the stair climbing state.

As a result of comparison, as shown in FIG. 15, the pressure value measured by the first pressure sensor 101 decreased by 100%, and the pressure value measured by the second pressure sensor 102 increased by 100%. Additionally, the pressure value measured by the third pressure sensor 103 decreased by 50%, and there was no difference in the pressure change of the fourth pressure sensor 104.

Expressing this as a color change, the first pressure sensor 101 and the third pressure sensor 101 are expressed in blue, the second pressure sensor 102 is expressed in red, and the fourth pressure sensor 104 is colorless. It was expressed as However, since the pressure change of the first pressure sensor 101 is higher than the pressure change of the third pressure sensor 103, it is expressed in a darker color.

Additionally, assuming that the user changes his walking motion from a standing state to a state of going down stairs, the pressure change analysis unit 1200 compares the initial pressure value with the pressure value measured in the state of going down stairs.

As a result of comparison, as shown in FIG. 16, the pressure values measured at the first pressure sensor 101, the second pressure sensor 102, the third pressure sensor 103, and the fourth pressure sensor 104 are all 100. % increased.

If this is expressed as a color change, the first pressure sensor 101, the second pressure sensor 102, the third pressure sensor 103, and the fourth pressure sensor 104 are all displayed in red.

Additionally, assuming that the user changes the walking motion from the standing state to the seated state, the pressure change analysis unit 1200 compares the initial pressure value with the pressure value measured in the seated state.

As a result of comparison, as shown in FIG. 17, the pressure value measured by the first pressure sensor 101 decreased by 100%, and the pressure value measured by the second pressure sensor 102 increased by 100%. Additionally, the pressure value measured by the third pressure sensor 103 increased by 50%, and there was no difference in the pressure value measured by the fourth pressure sensor 104.

Expressing this as a color change, the first pressure sensor 101 is expressed in blue, the second pressure sensor 102 and the third pressure sensor 103 are expressed in red, and the fourth pressure sensor 104 is colorless. It was expressed as However, since the pressure change of the second input sensor 102 is higher than the pressure change of the third pressure sensor 103, it is expressed in a darker color.

Additionally, assuming that the user changes the walking motion from the sitting state to the standing state, the pressure change analysis unit 1200 compares the pressure value measured in the sitting state with the pressure value in the standing state.

As a result of comparison, as shown in FIG. 18, the pressure values measured by the first pressure sensor 101, the second pressure sensor 102, and the third pressure sensor 103 maintain the pressure values measured in the seated state. and the pressure value measured by the fourth pressure sensor 104 increased by 50%.

Expressing this as a color change, the first pressure sensor 101, the second pressure sensor 102, and the third pressure sensor 103 were expressed in blue, and the fourth pressure sensor 104 was expressed in colorless.

Meanwhile, the pressure value measured by the fourth pressure sensor 104 is preferably increased by 50% and displayed in red, but this is the same as the initial pressure value, that is, the value measured by the fourth pressure sensor 104 in the upright state. It is expressed as colorless.

When step S520 is completed, the estimation unit 1300 estimates the user's walking intention according to the analysis result (S530).

The estimation unit 1300 compares the pressure change of each of the first pressure sensor 101, the second pressure sensor 102, the third pressure sensor 103, and the fourth pressure sensor 104 with a preset pressure change pattern. Estimate the user's walking intention.

At this time, the user's walking intention includes at least one of walking on level ground, going up or down stairs, stopping, sitting, and standing.

As explained in step S220, when the pressure value measured in the standing state is set as the initial pressure value, the change in pressure measured from the first pressure sensor 101 to the fourth pressure sensor 104 has a certain pattern. do.

Therefore, as described above, each pressure change pattern is set according to the walking motion, and if it is determined that the pressure value measured at the current time matches the preset pressure change pattern, the estimation unit 1300 determines the pressure change pattern according to the pressure change pattern. The user's walking intention can be estimated.

The present invention has been described with reference to the embodiments shown in the drawings, but these are merely illustrative, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true scope of technical protection of the present invention should be determined by the technical spirit of the attached patent claims.

Claims (15)

It relates to a pressure sensor mounted inside a femoral prosthesis socket, The sensor body is A first electrode plate on a square plate; A Velostat film laminated on the upper side of the first electrode plate in the form of a square plate; A second electrode plate, in the form of a rectangular plate, laminated on the upper side of the velostat film; a first insulating film laminated on the lower side of the first electrode plate to insulate the lower side of the sensor body; and A second insulating film is laminated on the upper side of the second electrode plate and insulates the upper side of the sensor body. A pressure sensor mounted inside a femoral prosthetic leg socket, characterized in that a plurality of incisions are formed on the outside of the sensor body corresponding to the inner curved surface of the prosthetic leg socket. In claim 1, The incision is A pressure sensor mounted inside a femoral prosthesis socket, characterized in that it is formed in a triangle. In claim 2, The incision is A pressure sensor mounted inside a femoral prosthesis socket, characterized in that it is formed at the center of the outer periphery of the sensor body on a square plate. In claim 3, The incision is A pressure sensor formed on the front, back, left, and right outer periphery of the sensor body on a square plate, respectively, and installed inside the femoral prosthesis socket forming four incisions. a) determining the internal curvature of the area where the pressure sensor is to be provided among the inside of the prosthetic leg socket; b) preparing a first electrode plate and a second electrode plate on a rectangular plate having the same area; c) Preparing a Velostat film; d) manufacturing a sensor body by stacking a first electrode plate and a second electrode plate on the upper and lower sides of the Velostat film, respectively, with the Velostat film interposed therebetween; e) cutting the sensor body so that an incision of the corresponding size is formed in response to the internal curvature of the prosthetic leg socket; a method of manufacturing a pressure sensor mounted inside a femoral prosthetic leg socket, including the step of cutting. In the walking intention estimation device using pressure changes, A pressure value acquisition unit that acquires each pressure value from a plurality of pressure sensors installed inside the femoral prosthesis socket; a pressure change analysis unit that analyzes the pressure change by comparing the pressure value obtained at the current time and the initial pressure value; and When it is determined that a pressure change has occurred, a walking intention estimation device using a pressure sensor mounted inside a femoral prosthesis socket including an estimation unit that estimates the user's walking intention using a pressure change pattern of a plurality of pressure values. In claim 6, The pressure sensor is A walking intention estimation device using a pressure sensor installed inside the femoral prosthesis socket to correspond to the front of the user's thigh, the back of the thigh, and the bottom of the cut portion. In claim 7, The pressure sensor is, A plurality of pieces are installed vertically on the inner front part of the femoral prosthesis socket, A walking intention estimation device using a pressure sensor mounted inside a femoral prosthetic leg socket, where one is installed on the inner bottom and inner rear of the femoral prosthetic leg socket. In claim 7, The pressure change analysis unit, Each pressure value measured immediately before the user performs a specific action is set as the initial pressure value, A walking intention estimation device using a pressure sensor mounted inside a prosthetic thigh socket that analyzes whether there is a change from the set initial pressure value. In claim 9, The estimation part is, A walking intention estimation device using a pressure sensor mounted inside a prosthetic femoral leg socket that estimates at least one walking intention among walking on level ground, going up or down stairs, stopping, sitting, and standing. In the walking intention estimation method using a walking intention estimation device, Obtaining each pressure value from a plurality of pressure sensors installed inside the femoral prosthesis socket; analyzing pressure changes by comparing the pressure value obtained at the current point in time with the initial pressure value; and When it is determined that a pressure change has occurred, a walking intention estimation method comprising the step of estimating the user's walking intention using a pressure change pattern of a plurality of pressure values. In claim 11, The pressure sensor is, A walking intention estimation method installed inside a femoral prosthesis socket so as to correspond to the front of the user's thigh, the back of the thigh, and the bottom of the cut portion. In claim 12, The pressure sensor is, A plurality of pieces are installed vertically on the inner front part of the femoral prosthesis socket, A walking intention estimation method where one is installed on the inner bottom and inner back of the femoral prosthesis socket. In claim 11, The step of analyzing the pressure change is, Each pressure value measured immediately before the user performs a specific action is set as the initial pressure value, A walking intention estimation method that analyzes whether there is a change from the set initial pressure value. In claim 14, The step of estimating the walking intention is, A walking intention estimation method that estimates at least one walking intention among walking on level ground, going up or down stairs, stopping, sitting, and standing.

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