An esophageal strain sensing system and reconstruction method based on nodal stress analysis and impedance plane measurement

Abstract

This invention relates to an esophageal strain sensing system and reconstruction method based on nodal stress analysis and impedance plane measurement, belonging to the field of tissue biomechanical detection technology. The invention aims to non-invasively detect esophageal motility disorders using an innovative flexible liquid-filled balloon sensor system. The core components of the system include a flexible balloon, a hollow catheter, and a composite impedance-piezoelectric sensor array. This array integrates piezoelectric sensors and equidistant impedance electrodes, enabling real-time capture of dynamic strain information and local stress changes during esophageal swallowing. The key technology of this invention lies in the design of a specialized strain feature reconstruction algorithm. This algorithm utilizes a multi-layer coupled physical field analysis method to achieve accurate dynamic reconstruction of the mechanical properties of key esophageal nodes and the spatial distribution characteristics of the lumen diameter from data collected under simulated peristalsis, normal swallowing, and various pathological conditions. This provides an important quantitative analysis tool for the early identification and treatment of esophageal motility disorders.

Description

Technical Field

[0001] This invention belongs to the field of tissue biomechanical detection technology, and relates to an esophageal strain sensing system and reconstruction method based on nodal stress analysis and impedance plane measurement. Background Technology

[0002] The esophagus has three narrow regions in its physiological structure. This not only increases the likelihood of friction and irritation during food passage, inducing or exacerbating the risk of esophageal diseases, but also adds difficulty to the smooth passage of medical diagnostic instruments and the accurate assessment of the internal condition of the esophagus. Existing detection technologies for esophageal motility disorders, such as high-resolution manometry (HRM) and functional endoluminal imaging probes (FLIP), while having clinical application value, still face some challenges: HRM technology is costly, has demanding implementation conditions, and cannot fully reveal subtle elastic changes in the esophageal lining; while FLIP is limited by its inability to directly quantify the complex interactions between the balloon, fluid, and catheter, and cannot accurately measure the strain response of different parts of the balloon under different mechanical conditions. Summary of the Invention

[0003] In view of this, the purpose of this invention is to provide an esophageal strain sensing system and reconstruction method based on nodal stress analysis and impedance plane measurement. It provides an aspirable insulated balloon-catheter flexible pressure ejection device capable of repeatedly detecting dynamic mechanical characteristics of different regions of the esophagus, and a corresponding mechanical information analysis algorithm is designed to capture dynamic strain information and local stress changes of the esophagus in real time during swallowing.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] An esophageal strain sensing system based on nodal stress analysis and impedance plane measurement includes a triaxial monorail coded robotic arm, an esophageal balloon stent equipped with a digital tensile tester, an esophageal sample, a balloon catheter based on a sensor array, a signal processing system, and a host computer.

[0006] The esophageal sample was divided into the first esophageal constriction, the second esophageal constriction, and the third esophageal constriction.

[0007] The esophageal balloon stent equipped with a digital tension gauge is mounted on a three-axis monorail coded robotic arm, and the first esophageal stenosis, the second esophageal stenosis and the third esophageal stenosis are respectively fixed on the esophageal balloon stent equipped with a digital tension gauge.

[0008] The balloon catheter based on the sensor array is placed in the esophageal sample. The balloon catheter based on the sensor array is connected to the signal processing system through the sensor interface. The signal processing system is connected to the host computer.

[0009] The signal processing system includes a piezoelectric signal acquisition module, an impedance excitation and acquisition module, a microcontroller core, a signal transmission module, and a power supply module.

[0010] The power module's power interface and power conversion module transmit external power to the piezoelectric signal acquisition module, impedance excitation and acquisition module, microcontroller core, and signal transmission module.

[0011] The core of the microcontroller includes an AD conversion circuit, a data storage module, a data processing module, a data transceiver module, an I / O control module, a crystal oscillator and decoupling module, and an MCU / CPU module, which are connected in sequence. The data processing module is also connected to the crystal oscillator and decoupling module. The AD conversion circuit receives multimode piezoelectric analog signals from the balloon catheter based on the sensor array. The I / O control module exchanges control commands with the balloon catheter based on the sensor array.

[0012] The piezoelectric signal acquisition module includes a multiplexed charge impedance matching circuit, a multiplexed voltage secondary amplifier circuit, a Bessel second-order low-pass filter circuit, and a 50Hz power frequency notch filter circuit connected in sequence; the multiplexed charge impedance matching circuit receives signals from a balloon catheter based on a sensor array through a piezoelectric array wire group; the 50Hz power frequency notch filter circuit outputs a multimode piezoelectric analog signal to the AD conversion circuit.

[0013] The impedance excitation and acquisition module includes an impedance excitation source emitting circuit, an equally spaced impedance loop signal gating circuit, and a difference calculation and filtering circuit connected in sequence. The impedance excitation source emitting circuit outputs a signal to the first and last electrodes of the balloon catheter based on the sensor array. The equally spaced impedance loop signal gating circuit receives signals from all the electrodes in the balloon catheter based on the sensor array through the impedance electrode wire group. The difference calculation and filtering circuit outputs control commands to the I / O control module.

[0014] The signal transmission module includes a USB conversion interface, a cascade interface, and a USB communication module; the USB conversion interface and the cascade interface receive signals from the data processing module, and the USB communication module receives signals from the USB conversion interface and then sends them to the host computer.

[0015] The sensor array-based balloon catheter is connected to a syringe for adjusting balloon inflation.

[0016] The three-axis monorail coded robotic arm can move along the XYZ three-axis coordinate direction to adjust the tension and height at the narrow part of the esophagus;

[0017] The balloon catheter based on the sensor array includes a linearly distributed composite impedance-piezoelectric sensor array, which includes piezoelectric sensors and equally spaced impedance electrodes, for real-time capture of dynamic strain information and stress changes at the esophageal stricture during swallowing.

[0018] Furthermore, the power conversion module is also connected to a voltage divider output module.

[0019] The esophageal strain reconstruction method based on the system of nodal stress analysis and impedance plane measurement includes key nodal stress reconstruction and cavity diameter reconstruction.

[0020] The dynamic fluid pressure on the surface of the piezoelectric sensor in the composite impedance-piezoelectric sensor array was obtained through finite element simulation. and the correction factor for elastic stress of the conduit The analytical function relationship between the compressive stresses in the four pressure loading regions of the balloon is shown in the following equation:

[0021]

[0022] Among them, fluid dynamic pressure Depend on and composition;

[0023] Defined by pressure applied by the simulated esophagus Solve for sensor output The process is a positive problem calculation denoted as The reverse process is denoted as ,in," This indicates a complex mathematical process of obtaining the right-hand parameter from the left-hand parameter;

[0024] As shown in the following formula:

[0025]

[0026] During the process, the pressure directly acts on the fluid domain and the pressure that causes elastic correction stress in the catheter Together they form a simulated esophageal pressure input load ;pass and Solve and The simulation and fitting process is denoted as and Similarly, the reconstruction process is denoted as follows: and ;

[0027] The luminal radius of different esophageal segments is detected using a flexible balloon based on a functional intracavitary imaging probe (FLIP). The balloon is filled with a conductive solution, and an array of impedance electrodes is installed at equal intervals along its axial direction on its surface. A reverse excitation current source is transmitted through the impedance electrodes located at both ends of the conductive solution within the balloon, forming a uniform current field within the balloon. When the balloon undergoes uneven deformation due to stress in different esophageal segments, the distance between the conductive solution surface and the electrodes varies, resulting in a stepped distribution of solution impedance detected by each impedance electrode that is inversely proportional to the radius of the liquid surface where the electrode is located. The sensor's back-end circuitry is equipped with an inverting amplification module to ensure that, according to the following mathematical relationship, the potential difference between adjacent electrodes is directly proportional to the luminal radius of the corresponding balloon segment:

[0028]

[0029] in, For the first The radius of the conductive liquid surface, The cavity diameter versus adjacent potential difference conversion constant, For the first The ground potential of each impedance electrode For the first The ground potential of each impedance electrode For the first Equivalent calculated voltage of each impedance electrode.

[0030] The beneficial effects of this invention are as follows: This invention acquires local strain information and stress data of the esophagus in real time through a piezoelectric-impedance composite array, and uses a multi-layer coupled physical field analysis method to achieve accurate dynamic reconstruction of the mechanical properties and spatial distribution characteristics of key nodes of the esophagus, thereby providing a quantitative analysis method with practical clinical value for the early identification and refined treatment of esophageal motility disorders.

[0031] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0032] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0033] Figure 1 This is a schematic diagram of the balloon structure;

[0034] Figure 2 This is a block diagram of a signal acquisition and processing terminal model.

[0035] Figure 3 A flowchart of the system clinical trial workflow;

[0036] Figure 4 This is a preliminary research model for esophageal function assessment under a composite array. Detailed Implementation

[0037] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0038] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0039] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0040] Please see Figures 1-4 . Figure 1This is a 3D model of the sensor front-end structure of the piezoelectric-impedance composite array. The balloon structure is made of medical-grade non-elastic flexible polyvinyl chloride (PVC) film. Its unique front-end design combines a curved hemispherical wall with a central cylindrical wall to ensure morphological stability and avoid significant deformation under various physiological loads such as fluid dynamic pressure, shear stress, and catheter traction. Inside this high-toughness film balloon, four linearly arranged composite impedance-piezoelectric sensor arrays are uniformly distributed on the catheter surface, while a front-end hydraulic sensor is added at the catheter tip as a detection inlet. Notably, the fluid volume inside the balloon can be flexibly adjusted according to actual detection requirements, allowing the balloon cavity to flexibly conform to and closely adhere to the dynamic changes of the esophageal lining tissue for detection. In the experiment, the piezoelectric sensor array captured the coupling stress at four nodes within the balloon in real time, while the uniformly arranged impedance electrode array, driven by the head and tail units, simultaneously detected the changes in the cavity diameter of seven different regions of the balloon. The front-end hydraulic sensor monitors the hydraulic status of the balloon inflation section near steady state. Figure 1 middle This represents the fluid filling degree within the closed balloon, specifically the percentage ratio of the current inflated fluid volume to its volume when fully inflated. The fluid level positions at different filling degrees are shown below. Figure 1 The liquid levels 1 to 6 are shown in the diagram. All collected signals are transmitted to the signal processing circuit via a conduit. After filtering, they are converted into a piezoelectric-impedance hybrid signal matrix and sent to the host computer. The system reads and further processes these signal matrices via serial port through embedded interface software, incorporating them into Algorithm 1: Node Pressure Reconstruction Algorithm and Algorithm 2: Cavity Diameter Distribution Reconstruction Algorithm, thereby achieving overall dynamic reconstruction of esophageal lumen diameter, stress, and strain.

[0041] like Figure 2 The circuit shown is a composite array signal acquisition and processing circuit, an integrated system designed for piezoelectric-impedance composite sensors. It is primarily used for real-time and accurate acquisition and processing of various physiological parameters within a balloon catheter. In the circuit, the piezoelectric sensor array monitors the dynamic stress changes at four key nodes of the balloon, while the impedance electrode array acquires lumen diameter information from seven different regions of the balloon through alternating current generated by an excitation source. The system utilizes multiplexed charge impedance matching, voltage amplification, and filtering techniques to convert the raw signal into a standardized analog voltage signal, which is then converted into a digital signal via an analog-to-digital converter (AD converter) and temporarily stored in a microcontroller (STM32F103C8T6). After processing, the signal is sent to a host computer via a communication module. Pre-designed algorithm models (such as node pressure reconstruction models and lumen diameter distribution reconstruction models) are used for analysis and processing, thereby achieving accurate reconstruction of esophageal strain and lumen diameter changes, providing crucial data support for the diagnosis of esophageal motility disorders. The entire circuit is compact and fully functional, ensuring the stability and accuracy of signal acquisition.

[0042] When the detection system is working, to ensure that the voltage between any two adjacent impedance electrodes is only related to the corresponding cavity radius of the liquid surface, a head-and-tail excitation mode should be adopted. That is, a pair of reverse excitation sources should be output at the first and last electrodes of the impedance array, as shown in the following formula:

[0043]

[0044] in Head impedance electrodes The output excitation current source, Tail impedance electrode The output excitation current sources, both have amplitudes. The power supply frequency is The initial phase is .

[0045] Because the fluid inside the capsule has good conductivity and fluidity, the excitation source will generate a uniform current field in the fluid domain within the closed capsule cavity. Therefore, the current amplitude of all impedance electrodes in the fluid domain is... According to Ohm's law, the dynamic voltage difference between any two adjacent electrode rings can be derived. for:

[0046]

[0047] in, The fluid domain current under the action of the excitation source, This represents the actual resistance difference between adjacent electrode rings.

[0048] Furthermore, the planar impedance value of a conductive solution at the same height as the impedance electrode is shown in the following formula:

[0049]

[0050] in, This is the solution plane impedance value. The distance between adjacent electrodes. The conductivity of the solution, This represents the radius of the cavity corresponding to the electrode center (referred to as the electrode cavity diameter). Furthermore, the difference between adjacent dynamic voltages can also be expressed as...

[0051]

[0052] When the impedance detection system is operating stably , , Both are constants, therefore the electrode cavity diameter and the adjacent dynamic voltage difference are... It is inversely proportional.

[0053] Therefore, to obtain a direct ratio that is easy to calculate, a reciprocal generator needs to be configured in the system circuit. Meanwhile, to ensure the stability of the piezoelectric-impedance composite array sensor system and the effectiveness of signal detection, the frequency of the impedance excitation current source needs to be consistent with the operating frequency of the piezoelectric sensor array, both set to 20Hz. Before the experiment, the balloon system needs to be tested for sealing and insulation. If the output voltage at the impedance voltage acquisition port shows a large jump, the experiment should be stopped immediately and the balloon system checked for leaks or insulation failures.

[0054] This invention uses a simulation parametric relationship fitting method to obtain an analytically reconstructable computational model for reconstructing the pressure load at key points in the esophagus during a simulated swallowing peristaltic wave experiment. In the theoretical analysis of the coupled physical field of the balloon system, the calculation equations for the elastic strain of the balloon catheter connector and the electromechanical coupling output of the piezoelectric sensor are analytically and reversibly valid. The dynamic fluid pressure on the sensor surface is obtained through finite element simulation. (Depend on and (Composition) and catheter elastic stress correction factor Pressure was applied to four pressure loading zones of the balloon (e.g.) Figure 1 The analytical function relationship between the compressive stresses in regions P1~P4 (as shown in the equation) is as follows:

[0055]

[0056] Defined by pressure applied by the simulated esophagus Solve for sensor output The process is a positive problem calculation denoted as The reverse process is denoted as As shown in the following formula:

[0057]

[0058] During the process, the pressure directly acts on the fluid domain and the pressure that causes elastic correction stress in the catheter Together they constitute the simulated esophageal pressure input load. .pass and Solve and The simulation and fitting process is denoted as and Similarly, the reconstruction process is denoted as follows: and .

[0059] The luminal radius of different esophageal segments is detected using a flexible balloon based on a FLIP architecture. The balloon is filled with a conductive solution, and an array of impedance electrodes is installed at equal intervals along its axial direction on its surface. A reverse excitation current source is transmitted through the impedance electrodes located at both ends of the conductive solution within the balloon, forming a uniform current field within the balloon. When the balloon undergoes uneven deformation due to stress in different esophageal segments, the distance between the conductive solution surface and the electrodes varies, resulting in a stepped distribution of the solution impedance detected by each impedance electrode that is inversely proportional to the radius of the liquid surface where the electrode is located. The sensor's back-end circuit is equipped with an inverting amplification module to ensure that, according to the following mathematical relationship, the potential difference between adjacent electrodes is directly proportional to the luminal radius of the corresponding balloon segment:

[0060]

[0061] in, For the first The radius of the conductive liquid surface, The cavity diameter versus adjacent potential difference conversion constant, For the first The ground potential of each impedance electrode For the first Equivalent calculated voltage of each impedance electrode.

[0062] By real-time detection of six equivalent voltages in the working current field, the dynamic vectors of the lumen radius of six uniform sections of the balloon can be directly obtained. The equivalent voltage matrix obtained within the standard working time is linearly related to the lumen radius matrix used for esophageal lumen diameter reconstruction, thereby realizing the reconstruction of lumen diameter distribution.

[0063] The entire implementation process is as follows: First, a sterilized, vacuum-sealed balloon and the distal end of the catheter in its location are introduced into the esophagus. After the physiological state stabilizes, the balloon is slowly and uniformly inflated to allow the esophageal muscular tissue to flexibly conform to the balloon cavity. Then, the external catheter is gently and uniformly pulled outside the body to ensure the balloon stably passes through the esophageal segment, including the narrow section. During the experiment, a piezoelectric sensor array dynamically senses the stress at the four coupled nodes within the balloon system. A uniformly distributed impedance electrode array, after being excited by its first and last units, dynamically senses the diameter of the seven balloon cavities in different regions. The hydraulic sensor at the distal end of the catheter senses the hydraulic pressure at the balloon inflation point under quasi-steady-state conditions. The signals collected by the sensor array are transmitted through the catheter to the signal processing system circuit. The filtered composite voltage signal forms a piezoelectric-impedance output matrix and is transmitted to the host computer. The embedded interface program reads the pre-processed output matrix through the system serial port and further incorporates it into the node pressure reconstruction model (Algorithm 1) and the cavity diameter distribution reconstruction model (Algorithm 2) to achieve cavity diameter-stress combined with esophageal strain reconstruction.

[0064] Esophageal function assessment using a composite array:

[0065] By incorporating sensing data acquired from a piezoelectric-impedance composite array in a simulated esophageal peristaltic wave experimental platform into the esophageal strain reconstruction method, a systematic analysis of the dynamic strain of a flexible balloon under a given load can be performed. To further promote the application of the esophageal strain detection system and reconstruction method designed in this invention in clinical medicine and to explore the potential of this device in esophageal disease detection, a preliminary model for research on esophageal function assessment methods based on composite arrays needs to be constructed. The overall analytical framework is as follows: Figure 4 As shown.

[0066] This invention aims to select three typical esophageal dysfunction conditions—achalasia, localized ulceration of the esophageal mucosa, and esophageal stricture caused by tissue cysts—as research controls for a feasibility analysis of simulated detection. First, the typical esophageal peristaltic waves of patients with these three conditions under HRM and FLIP detection will be equated as loading functions, and these three loading functions will be used as input conditions in simulated esophageal peristalsis experiments. Further, the piezoelectric array signal and impedance array obtained from the physical simulation experiment will be introduced into the balloon node load reconstruction model and the balloon lumen plane measurement model, respectively, to obtain the esophageal lumen strain characteristics. Finally, the strain reconstruction results under the three conditions will be compared with the peristaltic wave equivalent loading function and the strain reconstruction results of normal swallowing, and the detection effect of the three typical conditions will be preliminarily evaluated.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. An esophageal strain sensing system based on nodal stress analysis and impedance plane measurement, characterized in that: The system includes a three-axis monorail coded robotic arm, an esophageal balloon stent equipped with a digital force gauge, an esophageal sample, a balloon catheter based on a sensor array, a signal processing system, and a host computer; The esophageal sample was divided into the first esophageal constriction, the second esophageal constriction, and the third esophageal constriction. The esophageal balloon stent equipped with a digital tension gauge is mounted on a three-axis monorail coded robotic arm, and the first esophageal stenosis, the second esophageal stenosis and the third esophageal stenosis are respectively fixed on the esophageal balloon stent equipped with a digital tension gauge. The balloon catheter based on the sensor array is placed in the esophageal sample. The balloon catheter based on the sensor array is connected to the signal processing system through the sensor interface. The signal processing system is connected to the host computer. The sensor array-based balloon catheter is connected to a syringe for adjusting balloon inflation. The three-axis monorail coded robotic arm can move along the XYZ three-axis coordinate direction to adjust the tension and height at the narrow part of the esophagus; The balloon catheter based on the sensor array includes a linearly distributed composite impedance-piezoelectric sensor array, which includes piezoelectric sensors and equally spaced impedance electrodes, for real-time capture of dynamic strain information and stress changes at the esophageal stricture during swallowing. The system is used to perform an esophageal strain sensing method based on nodal stress analysis and impedance plane measurement, which includes key nodal stress reconstruction and cavity diameter reconstruction. This method includes key node stress reconstruction and cavity diameter reconstruction; The dynamic fluid pressure on the surface of the piezoelectric sensor in the composite impedance-piezoelectric sensor array was obtained through finite element simulation. and the correction factor for elastic stress of the conduit The analytical function relationship between the compressive stresses in the four pressure loading regions of the balloon is shown in the following equation: Among them, fluid dynamic pressure Depend on and composition; Defined by pressure applied by the simulated esophagus Solve for sensor output The process is a positive problem calculation denoted as The reverse process is denoted as ,in," This indicates a complex mathematical process of obtaining the right-hand parameter from the left-hand parameter; As shown in the following formula: During the process, the pressure directly acts on the fluid domain and the pressure that causes elastic correction stress in the catheter Together they form the simulated esophageal pressure input load ;pass and Solve and The simulation and fitting process is denoted as and Similarly, the reconstruction process is denoted as follows: and ; The luminal radius of different esophageal segments is detected using a flexible balloon based on a functional intracavitary imaging probe (FLIP). The balloon is filled with a conductive solution, and an array of impedance electrodes is installed at equal intervals along its axial direction on its surface. A reverse excitation current source is transmitted through the impedance electrodes located at both ends of the conductive solution within the balloon, forming a uniform current field within the balloon. When the balloon undergoes uneven deformation due to stress in different esophageal segments, the distance between the conductive solution surface and the electrodes varies, resulting in a stepped distribution of solution impedance detected by each impedance electrode that is inversely proportional to the radius of the liquid surface where the electrode is located. The sensor's back-end circuitry is equipped with an inverting amplification module to ensure that, according to the following mathematical relationship, the potential difference between adjacent electrodes is directly proportional to the luminal radius of the corresponding balloon segment: in, For the first The radius of the conductive liquid surface, The cavity diameter versus adjacent potential difference conversion constant, For the first The ground potential of each impedance electrode For the first The ground potential of each impedance electrode For the first Equivalent calculated voltage of each impedance electrode.

2. The esophageal strain sensing system based on nodal stress analysis and impedance plane measurement according to claim 1, characterized in that: The signal processing system includes a piezoelectric signal acquisition module, an impedance excitation and acquisition module, a microcontroller core, a signal transmission module, and a power supply module. The power module's power interface and power conversion module transmit external power to the piezoelectric signal acquisition module, impedance excitation and acquisition module, microcontroller core, and signal transmission module; the power conversion module is also connected to a voltage divider output module. The core of the microcontroller includes an AD conversion circuit, a data storage module, a data processing module, a data transceiver module, an I / O control module, a crystal oscillator and decoupling module, and an MCU / CPU module, which are connected in sequence. The data processing module is also connected to the crystal oscillator and decoupling module. The AD conversion circuit receives multimode piezoelectric analog signals from the balloon catheter based on the sensor array. The I / O control module exchanges control commands with the balloon catheter based on the sensor array. The piezoelectric signal acquisition module includes a multiplexed charge impedance matching circuit, a multiplexed voltage secondary amplifier circuit, a Bessel second-order low-pass filter circuit, and a 50Hz power frequency notch filter circuit connected in sequence; the multiplexed charge impedance matching circuit receives signals from a balloon catheter based on a sensor array through a piezoelectric array wire group; the 50Hz power frequency notch filter circuit outputs a multimode piezoelectric analog signal to the AD conversion circuit. The impedance excitation and acquisition module includes an impedance excitation source emitting circuit, an equally spaced impedance loop signal gating circuit, and a difference calculation and filtering circuit connected in sequence. The impedance excitation source emitting circuit outputs a signal to the first and last electrodes of the balloon catheter based on the sensor array. The equally spaced impedance loop signal gating circuit receives signals from all the electrodes in the balloon catheter based on the sensor array through the impedance electrode wire group. The difference calculation and filtering circuit outputs control commands to the I / O control module. The signal transmission module includes a USB conversion interface, a cascade interface, and a USB communication module; the USB conversion interface and the cascade interface receive signals from the data processing module, and the USB communication module receives signals from the USB conversion interface and then sends them to the host computer.

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