CN111248914B - Plantar pressure acquisition system - Google Patents

Abstract

The application relates to a plantar pressure collection system, which comprises: the film pressure sensor is used for acquiring a current sole pressure signal; the signal processing unit is used for converting the current sole pressure signal into a current sole voltage signal; and the controller is used for acquiring the current sole pressure value according to the current sole voltage signal. The application provides a technical scheme, not only can be accurate acquire the sole pressure value, small dress is convenient moreover, and the cost is with low costs.

Description

A plantar pressure collection system

Technical Field

The present application belongs to the technical field of wearable intelligent devices, and specifically relates to a plantar pressure collection system.

Background Art

When people walk, the pressure distribution on the soles of the feet is time-varying. Studying the pressure distribution on the soles of the feet is of great significance for walking gait analysis, especially for patients with leg and foot motor dysfunction (such as lameness, limb disability). By statistically analyzing the changes in the pressure distribution on the soles of these patients, on the one hand, it can help doctors understand the patients' condition and rehabilitation process, and on the other hand, it can be applied to the control of medical devices (such as prostheses).

Related technologies include a dot matrix contact force sensing type human foot pressure distribution measurement system developed using a new type of conductive rubber as the sensor material and a sensor array composed of multiple miniature pressure sensors. However, related technologies generally have the problem of large product size, inconvenience in wearing or high cost.

Summary of the invention

In order to at least to some extent overcome the problems in the related art that products are large in size, inconvenient to wear or expensive to manufacture, the present application provides a plantar pressure collection system.

According to a first aspect of an embodiment of the present application, a plantar pressure acquisition system is provided, the system comprising:

Thin film pressure sensor, used to collect current plantar pressure signal;

A signal processing unit, used for converting the current plantar pressure signal into a current plantar voltage signal;

The controller is used to obtain a current plantar pressure value according to the current plantar voltage signal.

Preferably, the signal processing unit comprises: a plurality of reference resistors and a plurality of analog-to-digital conversion modules;

The plurality of analog-to-digital conversion modules are used to convert the current plantar pressure signal into a current plantar voltage signal.

Furthermore, the number of the reference resistors is the same as the number of the analog-to-digital conversion modules;

The resistance values of all the reference resistors are the same.

Furthermore,

One end of each of the reference resistors is connected to an output end of the thin film pressure sensor, and the other end is connected to the controller;

Each connection point between the reference resistor and the output end of the thin film pressure sensor is connected to the input end of an analog-to-digital conversion module;

The output end of the analog-to-digital conversion module is connected to the controller;

The output end of the thin film pressure sensor which is not connected to the reference resistor is connected to the controller.

Preferably, the controller comprises:

A first acquisition module, configured to acquire the resistance value of the pressure sensitive area in the current thin film pressure sensor by using a polling method according to the current sole voltage signal;

The second acquisition module is used to use the resistance value of the pressure sensitive area in the current thin film pressure sensor as the input of a preset function to acquire the current plantar pressure value corresponding to the pressure sensitive area in the current thin film pressure sensor.

Furthermore, the first acquisition module includes:

A first determining submodule, configured to set a connection point between the reference resistor and the controller to be _Pa ;

Let the connection point between the output end of the thin film pressure sensor and the controller be P _b ;

Wherein, a∈[1,A], A is the total number of connection points between the reference resistor and the controller; b∈[1,B], B is the total number of connection points between the reference resistor and the controller;

A first selection submodule is used to select a connection point _Pd between the output end of the thin film pressure sensor and the controller as an output port and input a high level;

Select a connection point P _c between the reference resistor and the controller as an output port and input a low level;

Among them, d∈[1,B] and d≠b, c∈[1,A] and c≠a;

A second selection submodule, used for selecting a connection point _Pa between the other reference resistor and the controller as a high impedance state;

Selecting the connection point P _b between the output end of the other thin film pressure sensor and the controller to be in high impedance state;

A first acquisition submodule is used to acquire the resistance value of the effective pressure sensitive area connected to the analog-to-digital conversion module in the thin film pressure sensor, so that the resistance value of the effective pressure sensitive area connected to the analog-to-digital conversion module in the thin film pressure sensor is the resistance value of the pressure sensitive area in the current thin film pressure sensor;

A judgment submodule, used to judge whether the resistance values of all pressure-sensitive areas in the current thin-film pressure sensor are all obtained, and if so, output the resistance values of all pressure-sensitive areas in the current thin-film pressure sensor;

If not, then reselect a connection point _Pd between the output end of the thin film pressure sensor and the controller as the output port, and input a high level; reselect a connection point _Pc between the reference resistor and the controller as the output port, and input a low level; until the resistance values of all pressure sensitive areas in the current thin film pressure sensor are fully obtained.

Furthermore, the first acquisition submodule is specifically used to determine the resistance value R _j of the j-th effective pressure sensitive area connected to the analog-to-digital conversion module in the thin film pressure sensor according to the following formula:

In the above formula, i∈[1,N], N is the total number of analog-to-digital conversion modules; j∈[1,M], M is the total number of pressure-sensitive areas in the thin film pressure sensor; _UV is the voltage value of the high level, _Ui is the resistance between the i-th analog-to-digital conversion module and the thin film pressure sensor; _Ug is the resistance between the connection point _Pd and the thin film pressure sensor; _Rk is the resistance of the reference resistor corresponding to the connection point _Pc .

Furthermore, the second acquisition module includes:

A second acquisition submodule is used to acquire a preset function by using a data fitting method according to the historical resistance value of the pressure sensitive area in the thin film pressure sensor and the corresponding plantar pressure value of the pressure sensitive area in the thin film pressure sensor;

The third acquisition submodule is used to use the resistance value of the pressure sensitive area in the current thin film pressure sensor as the input of a preset function to acquire the current plantar pressure value corresponding to the pressure sensitive area in the current thin film pressure sensor.

Preferably, the system further comprises: a power supply unit for supplying power to the plantar pressure acquisition system.

Preferably, the system further comprises: a communication unit, configured to transmit the current plantar pressure value acquired by the controller to a receiving terminal.

The technical solution provided by the embodiments of the present application may have the following beneficial effects:

The plantar pressure collection system constructed by thin film pressure sensor, signal processing unit and controller can not only accurately obtain the plantar pressure value, but also has small size, easy to wear, low cost, and is conducive to the development of medical industry.

It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

FIG1 is a schematic structural diagram of a plantar pressure acquisition system according to an exemplary embodiment;

FIG2 is a schematic structural diagram of another plantar pressure acquisition system according to an exemplary embodiment;

FIG3 is a schematic structural diagram of another plantar pressure collection system according to an exemplary embodiment;

FIG4 is a schematic diagram showing the distribution of pressure sensitive areas in a thin film pressure sensor in another plantar pressure collection system according to an exemplary embodiment;

FIG5 is a schematic diagram of the structure of a thin film pressure sensor of another plantar pressure collection system according to an exemplary embodiment;

FIG6 is a schematic diagram of an equivalent resistor network in another plantar pressure acquisition system according to an exemplary embodiment;

Fig. 7 is a schematic structural diagram of another plantar pressure acquisition system according to an exemplary embodiment.

DETAILED DESCRIPTION

Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

FIG. 1 is a schematic structural diagram of a plantar pressure acquisition system according to an exemplary embodiment. As shown in FIG. 1 , the system includes:

Thin film pressure sensor, used to collect current plantar pressure signal;

A signal processing unit, used for converting a current plantar pressure signal into a current plantar voltage signal;

The controller is used to obtain the current plantar pressure value according to the current plantar voltage signal.

The plantar pressure collection system provided in this embodiment can not only accurately measure the plantar pressure value, but also has a small size, is easy to wear, and has a low cost, which is conducive to the development of the medical industry.

As an improvement of the above embodiment, the present invention provides another structural schematic diagram of a plantar pressure collection system, as shown in FIG2 , including:

Thin film pressure sensor, used to collect current plantar pressure signal;

A signal processing unit, used for converting a current plantar pressure signal into a current plantar voltage signal;

The controller is used to obtain the current plantar pressure value according to the current plantar voltage signal.

It is easy to understand that the thin film pressure sensor includes several pressure sensitive areas, and each pressure sensitive area is equivalent to a variable resistor.

It should be noted that those skilled in the art may set the number of pressure sensitive areas in the thin film pressure sensor according to experience or engineering needs.

It is easy to understand that the plantar pressure collection system provided in the present application is arranged in the shoe, and can be arranged below the insole, above the insole or inside the insole.

Further optionally, the signal processing unit includes: a plurality of reference resistors and a plurality of analog-to-digital conversion modules;

A plurality of analog-to-digital conversion modules are used to convert the current plantar pressure signal into the current plantar voltage signal.

It is easy to understand that the analog-to-digital conversion module converts the current plantar pressure signal from an analog quantity to a digital quantity so that the controller can identify the current plantar pressure signal.

It should be noted that a reference is required when measuring the plantar pressure value, and the reference resistor is used as a comparison value; those skilled in the art can set the resistance value of the reference resistor according to engineering needs or experimental data.

It should be noted that the “analog-to-digital conversion module” involved in this embodiment is well known to those skilled in the art, and therefore, its specific implementation will not be described in detail.

Further optionally, the number of reference resistors is the same as the number of analog-to-digital conversion modules;

All reference resistors have the same resistance value.

For example, the resistance of the reference resistor is 300KΩ.

Further optionally, one end of each reference resistor is connected to an output end of the thin film pressure sensor, and the other end is connected to the controller;

The connection point between each reference resistor and the output end of the thin film pressure sensor is connected to the input end of an analog-to-digital conversion module;

The output end of the analog-to-digital conversion module is connected to the controller;

The output end of the thin film pressure sensor which is not connected to the reference resistor is connected to the controller.

Further optionally, the controller comprises:

A first acquisition module is used to obtain the resistance value of the pressure sensitive area in the current thin film pressure sensor by using a polling method according to the current plantar voltage signal;

A second acquisition module is used to use the resistance value of the pressure sensitive area in the current thin film pressure sensor as an input of a preset function to acquire the current plantar pressure value corresponding to the pressure sensitive area in the current thin film pressure sensor;

It should be noted that the “polling method” involved in this embodiment is well known to those skilled in the art, and therefore, its specific implementation will not be described in detail.

Further optionally, the first acquisition module includes:

A first determining submodule, used to set the connection point between the reference resistor and the controller to be _Pa ;

Let the connection point between the output end of the thin film pressure sensor and the controller be P _b ;

Wherein, a∈[1,A], A is the total number of connection points between the reference resistor and the controller; b∈[1,B], B is the total number of connection points between the reference resistor and the controller;

The first selection submodule is used to select a connection point _Pd between the output end of a thin film pressure sensor and the controller as an output port and input a high level;

Select a connection point P _c between a reference resistor and the controller as the output port and input a low level;

Among them, d∈[1,B] and d≠b, c∈[1,A] and c≠a;

The second selection submodule is used to select the connection point P _a between other reference resistors and the controller as a high impedance state;

Select the connection point P _b between the output end of other thin film pressure sensors and the controller as high impedance state;

The first acquisition submodule is used to acquire the resistance value of the effective pressure sensitive area connected to the analog-to-digital conversion module in the thin film pressure sensor, so that the resistance value of the effective pressure sensitive area connected to the analog-to-digital conversion module in the thin film pressure sensor is the resistance value of the pressure sensitive area in the current thin film pressure sensor;

A judgment submodule, used to judge whether the resistance values of all pressure-sensitive areas in the current thin-film pressure sensor are all obtained, and if so, output the resistance values of all pressure-sensitive areas in the current thin-film pressure sensor;

If not, then reselect a connection point _Pd between the output end of the thin film pressure sensor and the controller as the output port, and input a high level; reselect a connection point _Pc between the reference resistor and the controller as the output port, and input a low level; until the resistance values of all pressure sensitive areas in the current thin film pressure sensor are obtained.

Further optionally, the first acquisition submodule is specifically used to determine the resistance value R _j of the j-th effective pressure sensitive area connected to the analog-to-digital conversion module in the thin film pressure sensor according to the following formula:

In the above formula, i∈[1,N], N is the total number of analog-to-digital conversion modules; j∈[1,M], M is the total number of pressure-sensitive areas in the thin film pressure sensor; _UV is the voltage value of the high level, _Ui is the resistance value between the i-th analog-to-digital conversion module and the thin film pressure sensor; _Ug is the resistance value between the connection point _Pd and the thin film pressure sensor; _Rk is the resistance value of the reference resistor corresponding to the connection point _Pc .

Further optionally, the second acquisition module includes:

A second acquisition submodule is used to acquire a preset function by using a data fitting method according to the historical resistance value of the pressure sensitive area in the thin film pressure sensor and the corresponding plantar pressure value of the pressure sensitive area in the thin film pressure sensor;

The third acquisition submodule is used to use the resistance value of the pressure sensitive area in the current thin film pressure sensor as the input of a preset function to acquire the current plantar pressure value corresponding to the pressure sensitive area in the current thin film pressure sensor.

Further optionally, the system also includes: a power supply unit for supplying power to the plantar pressure acquisition system.

It should be noted that those skilled in the art can set the type of power supply unit according to engineering needs or actual needs. For example, a 1S lithium battery (3.7V) with a capacity of 300mAH can be selected.

Further optionally, the system further includes: a communication unit, configured to transmit the current plantar pressure value acquired by the controller to a receiving terminal;

The controller is also used to send the acquired current plantar pressure value to the communication unit.

In some embodiments, the communication unit may transmit the current plantar pressure value acquired by the controller to the receiving terminal through, but not limited to, ZigBee communication technology.

The plantar pressure collection system provided in this embodiment can detect plantar pressure in real time, effectively improving the accuracy of pressure detection; it has low cost, low power consumption, wide applicability, and is small in size and easy to wear.

In order to further illustrate the above-mentioned plantar pressure collection system, the present application provides a specific plantar pressure collection system, see FIG3 , comprising: a thin film pressure sensor, 4 reference resistors and a CC2530 processor;

Furthermore, the thin film pressure sensor is a piezoresistive thin film pressure sensor.

It should be noted that the thin film pressure sensor is configured to be in the shape of an insole so as to be easily placed in a shoe.

Furthermore, as shown in FIG. 4 and FIG. 5 , the thin film pressure sensor includes 16 pressure sensitive areas; the thin film pressure sensor includes, from top to bottom, a first conductive layer, a pressure sensitive material and a second conductive layer.

It should be noted that each pressure sensitive area is equivalent to a variable resistor, and when the pressure acting on each area changes, the corresponding resistance value will also change.

Further, as shown in FIG3 , 16 pressure sensitive areas in the thin film pressure sensor and 4 reference resistors form a resistor network, and the resistor network includes 10 IO interfaces, namely P1.0 to P1.7, P2.1 and P2.2, and the 10 IO interfaces are all connected to the GPIO of the CC2530 processor;

The connection point between each reference resistor and the thin film pressure sensor is an ADC node, and each ADC node is respectively connected to an ADC channel of the CC2530 processor; wherein the four ADC nodes are N1 to N4; and the four ADC channels of the CC2530 processor are P0.4 to P0.7.

Specifically, the resistance of each reference resistor is 300KΩ, and the four reference resistors are Ref1 to Ref4.

Furthermore, the four ADC channels of the CC2530 processor are used to obtain the voltage values of the four ADC nodes respectively.

Further, the CC2530 processor is used to analyze the circuit network using the polling method and Kirchhoff's current law to obtain the resistance value of each pressure sensitive area (variable resistor);

The corresponding plantar pressure value of each pressure sensitive area (variable resistor) is obtained by using the resistance value of each pressure sensitive area (variable resistor) and a preset function.

It should be noted that the “polling method and Kirchhoff's current law” involved in this embodiment are well known to those skilled in the art, and therefore, their specific implementation methods are not described in detail.

Furthermore, the circuit network is analyzed using the polling method and Kirchhoff's current law to obtain the resistance value of each pressure sensitive area (variable resistor), including:

Step 1: Select P1.0 among IO interfaces P1.0~P1.3, P2.1 and P2.2 as the output port, and input a high level; select P1.4 among IO interfaces P1.4~P1.7 as the output port, and output a low level, and set the other IO interfaces to high impedance; in this way, the resistor network is equivalent to the resistor network shown in Figure 6;

The inflow current of the resistor network in the dotted box in Figure 6 is equal to the outflow current, that is:

i _in1 +i _in2 +i _in3 +i _in4 ＝i _o1 +i _o2 +i _o3 +i _o4 (1)

And since i _o2 =i _o3 =i _o4 =0, equation (1) can be converted into the following equation:

In the above formula, _U1 ~ _U4 are the voltage values of the four ADC nodes obtained by the ADC channel in the CC2530 processor, and _UV is the high-level voltage at the IO interface P1.0;

Step 2: Select P1.0 among IO interfaces P1.0~P1.3, P2.1 and P2.2 as the output port, and input a high level; select P1.5 among IO interfaces P1.4~P1.7 as the output port, and output a low level. Set the other IO interfaces to high impedance state;

Similarly, according to the principle in step 1, we get the following formula:

In the above formula, U′ _t (t＝1,2,3,4) is the voltage value of the 4 ADC nodes re-acquired by the ADC channel in the CC2530 processor;

Step 3: Select P1.0 among IO interfaces P1.0~P1.3, P2.1 and P2.2 as the output port, and input high level; select P1.6 among IO interfaces P1.4~P1.7 as the output port, and output low level; set other IO interfaces to high impedance state;

Similarly, according to the principle in step 1, we get the following formula:

In the above formula, U″ _t (t＝1,2,3,4) is the voltage value of the 4 ADC nodes re-acquired by the ADC channel in the CC2530 processor;

Step 4: Select P1.0 among IO interfaces P1.0~P1.3, P2.1 and P2.2 as the output port, and input high level; select P1.7 among IO interfaces P1.4~P1.7 as the output port, and output low level; set other IO interfaces to high impedance state;

Similarly, according to the principle in step 1, we get the following formula:

In the above formula, U″′ _t (t＝1,2,3,4) is the voltage value of the 4 ADC nodes re-acquired by the ADC channel in the CC2530 processor;

Step 5: According to formulas (2) to (5), the following formula can be obtained:

In the above formula, C is a 4×4 matrix, D is a column vector, and solving formula (5) obtains the reciprocal values of the variable resistors R1 to R4;

Step 6: Reselect one of the IO interfaces P1.0 to P1.3, P2.1 and P2.2 as the output port, and input a high level; select one of the IO interfaces P1.4 to P1.7 as the output port, and output a low level; similarly, according to the principles in steps (1) to (5), obtain the inverse values of all variable resistors.

Furthermore, using the resistance value of each pressure sensitive area (variable resistor) and a preset function, the corresponding plantar pressure value of each pressure sensitive area (variable resistor) is obtained, including:

According to the historical resistance value of the pressure sensitive area in the thin film pressure sensor and the corresponding plantar pressure value of the pressure sensitive area in the thin film pressure sensor, the preset function is obtained by using the data fitting method:

y＝0.0058x+0.0022

In the above formula, x is the reciprocal of the variable resistance, the unit is KΩ; y is the pressure value, the unit is N.

Furthermore, the CC2530 processor also includes: a ZigBee wireless communication unit, which is used to transmit the plantar pressure value obtained by the CC2530 processor to a receiving end;

The receiving end may include but is not limited to: a computer or a mobile phone;

For example, the interface of the receiving end is shown in FIG7 .

Furthermore, the system also includes: a power supply unit, which is used to supply power to the plantar pressure collection system.

The power supply unit may be, but is not limited to, a lithium battery (3.7V) with a capacity of 300mAH.

The plantar pressure collection system provided in this embodiment can detect plantar pressure in real time; it adopts the CC2530 processor, and utilizes its built-in 8-way 14-bit AD channels and wireless communication functions to effectively improve the accuracy of pressure detection; it adopts a relatively cheap thin film pressure sensor, whose shape matches the structure of the foot, and the material is relatively soft, and easy to be placed in different shoes; the plantar pressure collection system provided in this embodiment has low cost, low power consumption, wide applicability, and small size (30*30mm) and is easy to wear; at the same time, it can also contribute to the medical industry.

It can be understood that the same or similar parts of the above embodiments can be referenced to each other, and the contents not described in detail in some embodiments can refer to the same or similar contents in other embodiments.

It should be noted that, in the description of this application, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of this application, unless otherwise specified, the meaning of "plurality" refers to at least two.

Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

The storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk, etc.

In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims (9)

1. A plantar pressure acquisition system, comprising:

the film pressure sensor is used for acquiring a current sole pressure signal;

the signal processing unit is used for converting the current sole pressure signal into a current sole voltage signal;

the controller is used for acquiring a current sole pressure value according to the current sole voltage signal;

wherein the signal processing unit includes: the device comprises a plurality of reference resistors and a plurality of analog-to-digital conversion modules, wherein one end of each reference resistor is connected with one output end of a film pressure sensor, and the other end of each reference resistor is connected with a controller; the connection point between each reference resistor and the output end of the film pressure sensor is connected with the input end of one analog-to-digital conversion module;

the controller includes: a first acquisition module and a second acquisition module; the first acquisition module is used for acquiring the resistance value of a pressure sensitive area in the current film pressure sensor; the second acquisition module is used for acquiring a current plantar pressure value corresponding to a pressure sensitive area in the current film pressure sensor;

the first obtaining module includes:

a first determination submodule for making a connection point between the reference resistance and the controller be P _a ；

The connection point between the output end of the film pressure sensor and the controller is P _b ；

Wherein a ∈ [1, A ], A is the total number of connection points between the reference resistance and the controller; b ∈ [1, B ], B being the total number of connection points between the reference resistance and the controller;

a first selection submodule for selecting a connection point P between the output of the membrane pressure sensor and the controller _d Inputting high level for output port;

selecting a connection point P between the reference resistor and the controller _c Inputting low level for output port;

wherein d belongs to [1, B ] and d is not equal to b, c belongs to [1, A ] and c is not equal to a;

second selection submodelA block for selecting a connection point P between the other reference resistors and the controller _a Is in a high resistance state;

selecting a connection point P between the output ends of the other film pressure sensors and the controller _b Is in a high resistance state;

the first acquisition submodule is used for acquiring the resistance value of an effective pressure sensitive area connected with the analog-to-digital conversion module in the film pressure sensor, and the resistance value of the effective pressure sensitive area connected with the analog-to-digital conversion module in the film pressure sensor is made to be the resistance value of the pressure sensitive area in the current film pressure sensor;

the judging submodule is used for judging whether the resistance values of all the pressure sensitive areas in the current film pressure sensor are completely acquired, and if so, outputting the resistance values of all the pressure sensitive areas in the current film pressure sensor;

if not, reselecting a connection point P between the output end of the film pressure sensor and the controller _d Inputting high level for output port; reselecting a connection point P between the reference resistor and the controller _c Inputting low level for output port; until the resistance values of all pressure sensitive areas in the current film pressure sensor are all obtained.

2. The system according to claim 1, wherein said analog-to-digital conversion modules are configured to convert said current plantar pressure signal into a current plantar voltage signal.

3. The system of claim 2, wherein the number of reference resistors is the same as the number of analog-to-digital conversion modules;

all the reference resistors have the same resistance value.

4. The system of claim 2, wherein the output of the analog-to-digital conversion module is connected to a controller;

the output end of the film pressure sensor which is not connected with the reference resistor is connected with the controller.

5. The system according to claim 4, wherein the first obtaining module is configured to obtain the current resistance value of the pressure sensitive area in the thin film pressure sensor by using a polling method according to the current sole voltage signal;

and the second acquisition module is used for inputting the resistance value of the pressure sensitive area in the current film pressure sensor into a preset function and acquiring the current sole pressure value corresponding to the pressure sensitive area in the current film pressure sensor.

6. The system of claim 1, wherein the first obtaining submodule is specifically configured to determine a resistance value R of a jth effective pressure sensitive area of the thin film pressure sensor coupled to the analog-to-digital conversion module according to the following formula _j ：

In the above formula, i is E [1, N]N is the total number of the analog-to-digital conversion modules; j belongs to [1,M ]]M is the total number of pressure sensitive areas in the film pressure sensor; u shape _V Is a voltage value of the high level, U _i The resistance value between the ith analog-to-digital conversion module and the film pressure sensor is obtained; u shape _g Is the connection point P _d A resistance value with the thin film pressure sensor; r _k Is a connection point P _c The corresponding resistance value of the reference resistor.

7. The system of claim 5, wherein the second obtaining module comprises:

the second acquisition submodule is used for acquiring a preset function by using a data fitting method according to the resistance value of a pressure sensitive area in the historical film pressure sensor and the corresponding plantar pressure value of the pressure sensitive area in the historical film pressure sensor;

and the third obtaining submodule is used for inputting the resistance value of the pressure sensitive area in the current film pressure sensor into a preset function and obtaining the current sole pressure value corresponding to the pressure sensitive area in the current film pressure sensor.

8. The system according to any one of claims 1-7, further comprising: and the power supply unit is used for supplying power to the plantar pressure acquisition system.

9. The system according to any one of claims 1-7, further comprising: and the communication unit is used for transmitting the current sole pressure value acquired by the controller to a receiving terminal.

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