Wearable respiration monitoring device based on flexible piezoelectric film material

Abstract

The utility model discloses a wearable respiration monitoring device based on a flexible piezoelectric film material, and belongs to the field of wearable monitoring instruments. Comprising a signal receiving module (1), a signal processing module (2) and a data conversion module (3), the signal receiving module is electrically connected with the signal processing module, the signal processing module is electrically connected with the data conversion module, mechanical energy generated by human respiration is converted into an electric signal through a flexible piezoelectric material, and after rear-end signal processing, the electric signal is transmitted to the data conversion module (3). Information is transmitted to a mobile terminal through the Bluetooth module, so that accurate and real-time human body breathing state detection is realized, the human body life health condition is evaluated, and guardians are helped to know the respiratory system health condition and the life health condition of a user. The device has high-sensitivity and high-comfort human respiration monitoring capability, and provides an important promotion effect for the fields of sensing technology and wearable monitoring instruments.

Description

Technical Field

[0001] This utility model belongs to the fields of new materials, sensing technology, and wearable monitoring instruments, and specifically relates to the design and fabrication of a flexible piezoelectric sensor. Background Technology

[0002] With the rapid development of flexible material fabrication technology and Internet of Things (IoT) technology, the design of wearable vital sign monitoring devices based on flexible materials for monitoring human movement and health status has become a current research hotspot. The capture and recording of physiological signals is crucial for health management and disease treatment. However, traditional physiological signal detection sensors lack comfort and sensitivity. With the steady development of piezoelectric sensors, known for their higher sensitivity, faster response, corrosion resistance, and higher efficiency, piezoelectric sensors have emerged as a preferred choice among various sensors. Organic piezoelectric materials, represented by polydimethylsiloxane (PDMS), surpass inorganic piezoelectric materials, possessing numerous advantages such as biocompatibility and fragility, making them the preferred sensor material for monitoring vital signs. The barium calcium zirconate titanate (BCZT) / PDMS flexible piezoelectric composite material utilizes the piezoelectric properties provided by the nano-piezoelectric ceramic BCZT; PDMS has a Young's modulus of 1.24 MPa, close to that of human skin. The composite material prepared by dielectrophoresis can yield a piezoelectric material that combines electromechanical conversion properties with flexibility.

[0003] Currently, the methods for building a wearable vital signs monitoring system are relatively mature. However, it still suffers from problems such as large size, inconvenience in carrying, and poor remote monitoring capabilities. Therefore, eliminating unnecessary wires and external power supplies to reduce the weight and size of the product structure, making it easier to carry and miniaturizing it, and using Bluetooth modules to remotely transmit intelligently processed information wirelessly, represents the future development direction for wearable vital signs monitoring devices. Utility Model Content

[0004] The purpose of this invention is to provide a wearable respiratory monitoring device based on a flexible piezoelectric thin film material. This device converts the mechanical energy generated by human respiration into electrical signals using the flexible piezoelectric material. After signal processing, the information is transmitted to a mobile terminal via a Bluetooth module. This system can accurately and in real-time detect information about the human respiratory state, helping others understand the user's respiratory health and overall health status.

[0005] The technical solution to achieve the purpose of this utility model is as follows:

[0006] A wearable respiratory monitoring device based on flexible piezoelectric thin film material, which includes three modules, specifically: a signal receiving module (1), a signal processing module (2), and a data conversion module (3). The signal receiving module is electrically connected to the signal processing module, and the signal processing module is electrically connected to the data conversion module;

[0007] The signal receiving module is composed of a flexible BCZT / PDMS composite piezoelectric thin film material array, which is used to receive the signals generated by breathing; in the signal receiving module, the array units are connected by electrode wires to form an array mode of 2 strings in series and 4 in parallel. The sizes of the eight BCZT / PDMS piezoelectric composite material units in the signal receiving module are all 0.5 cm × 1.0 cm, and the thickness is 0.15 - 0.20 mm.

[0008] The array mode of 2 strings in series and 4 in parallel means that eight BCZT / PDMS piezoelectric composite material units are arranged in two columns, with 4 units in each column. One column is connected by wires with the positive electrode, and the other column is connected by wires with the negative electrode. At the same time, one unit of the positive electrode is electrically connected to one unit of the negative electrode one by one; the signal receiving module is located at the chest part of the human body, and the whole device can be made into a vest structure, and then the signal receiving module is located at the chest part of the human body;

[0009] Both the upper and lower surfaces of the flexible BCZT / PDMS piezoelectric composite material in the signal receiving module are coated with silver layers to conduct current and transmit the received vital sign signals to the signal processing module in the form of electrical signals.

[0010] The outside of the signal receiving module is encapsulated with insulating glue to reduce the interference of external electrical signals on the sensing array.

[0011] The lead-free piezoelectric material BCZT / PDMS in the signal receiving module is prepared by dielectrophoresis technology.

[0012] The signal processing module can process the signals received by the signal receiving module; it includes components such as a preamplifier, a filter, and an analog-to-digital converter (ADC);

[0013] Each component of the signal processing module requires an external power supply for power supply. ">

[0014] The data conversion module consists of a Bluetooth module and a mobile terminal, and transmits the data processed by the signal processing module to the mobile terminal through Bluetooth for data presentation on the mobile terminal.

[0015] Compared with the prior art, the remarkable advantages of this utility model are:

[0016] (1) Compared with traditional lead-containing piezoelectric materials, the selection of lead-free piezoelectric material BCZT / PDMS as the material unit of the sensor helps to promote the application of environmentally friendly materials; the fabricated unit array has good piezoelectric properties and good flexibility when placed on the chest, and can be used as a new generation of flexible piezoelectric materials for wearable applications; the array mode composed of 2 strings in series and 4 in parallel can sensitively reflect the breathing characteristics.

[0017] (2) Through module combination and mastering the combination of software and hardware, after the device module receives the processed data, the system outputs the signal and gives an immediate feedback display on its own. Brief Description of the Drawings

[0018] Figure 1 It is a diagram of a wearable breathing monitoring device made of flexible BCZT / PDMS piezoelectric composite film material

[0019] Figure 2 It is a schematic diagram of a flexible BCZT / PDMS sensor;

[0020] Figure 3 It is a structural diagram of a breathing sensing array of flexible BCZT / PDMS piezoelectric composite material

[0021] Figure 4 It is the display of the measurement results on the display interface of the mobile device.

[0022] (1) Signal receiving module, (2) Signal processing module, (3) Data conversion module, (11) FPC wire, (12) BCZT / PDMS piezoelectric composite material array, (13) Encapsulation component, (14) Flexible material PDMS vest material. Detailed Implementation Modes

[0023] Next, in combination with the drawings in the content of the present utility model, the specific implementation schemes will be described in detail to further clarify the purpose, advantages and features of the utility model. The specific implementations described below are only used to explain the present utility model, and all technical solutions adopted in a similar manner fall within the scope claimed by the present utility model.

[0024] Example 1

[0025] The signal processing module is specifically composed of components such as chip capacitors, chip inductors, chip resistors, operational amplifiers, TVS diodes, etc., and can perform processing such as amplifying, filtering, and AD conversion on the collected data.

[0026] In the data conversion module, the Bluetooth MCU is nrf52832 for data transmission.

[0027] The Bluetooth MCU in the data conversion module is developed based on Keil software to enable it to have the function of data transmission.

[0028] A wearable respiratory monitoring device based on flexible barium calcium zirconate titanate / polydimethylsiloxane (BCZT / PDMS) piezoelectric material is disclosed. The device has a vest-like structure with a signal receiving module located on the chest. This module is composed of an array of flexible BCZT / PDMS composite piezoelectric thin films and is used to receive respiratory signals. The array units in the signal receiving module are connected by electrode wires to form a 2-series, 4-parallel array configuration. Each of the eight BCZT / PDMS piezoelectric composite material units in the signal receiving module is 0.5cm × 1.0cm in size and 0.15–0.20mm thick, connected by wires.

[0029] The signal processing module processes the signals generated by the sensor through amplification, filtering, and other methods. It includes components such as amplifiers, filters, and analog-to-digital converters (ADCs). Through this processing, the respiratory signals acquired by the sensor (including respiratory fluctuation images and frequencies) can be converted into digital signals, allowing for precise information extraction.

[0030] The data conversion module consists of a Bluetooth module and a mobile terminal. It transmits the data processed by the signal processing module to the mobile terminal via Bluetooth, where the data is presented. This module can display the respiratory fluctuation image, respiratory rate, and other data processed by the signal processing module on the screen of the mobile terminal, and provide information feedback through the display screen, sound prompts, vibration, and other means, showing users some basic vital signs information.

[0031] This invention provides a wearable respiratory monitoring device based on BCZT / PDMS piezoelectric composite flexible thin film material. The composition principle of the entire device is as follows: Figure 1 As shown. The flexible respiratory monitoring sensor's core component is an array of flexible BCZT / PDMS composite piezoelectric film material. During human respiration, the movement of the chest cavity causes deformation of the BCZT / PDMS composite piezoelectric film material. This deformation creates a potential difference, and the energy generated by this potential difference is transmitted to the back-end signal processing module via FPC wires. Each unit of the BCZT / PDMS piezoelectric composite material array that monitors human respiration has an electrode wire, and the units are connected in series and parallel. The subsequent signal processing module amplifies, filters, and performs AD conversion on the collected data, mainly including preamplifiers, filters, and analog-to-digital converters (ADCs). After processing by the signal processing module, the signal collected by the sensor is converted into a digital signal, accurately extracting the collected information. The processed information is then transmitted wirelessly through a Bluetooth module (the recommended Bluetooth MCU is the nrf52832, developed using Keil software to enable data transmission). Figure 4 The measurement results are displayed on the mobile device's screen.

[0032] Figure 2 It is a flexible BCZT / PDMS sensor. When a human breathes, the abdomen slightly contracts and relaxes, causing the BCZT / PDMS piezoelectric composite material to deform, thereby generating an electrical signal. The thickness of the piezoelectric composite material BCZT / PDMS is 0.15 - 0.20 mm, and all the BCZT / PDMS in this signal receiving module are connected in parallel. Figure 2 In it, 11 is an FPC wire directly connected to the sensor, leading out the positive electrode above and the negative electrode below. Figure 2 In it, 12 is an array attached with the flexible BCZT / PDMS piezoelectric composite material. It is the component for receiving vital sign signals and also the core component of this device. Silver layers are coated on both the upper and lower sides of this component, which can transmit the received vital sign signals to the backend in the form of electrical signals. Figure 2 In it, 13 is an insulating encapsulation component. It is recommended to use insulating glue to encapsulate the device to reduce the interference of external electrical signals on the sensing array and make the received signals more accurate.

[0033] Figure 3 It is a structural diagram of a breathing sensing array containing the flexible BCZT / PDMS piezoelectric composite material. Figure 3 In it, 12 is a 0.5 cm × 1.0 cm flexible BCZT / PDMS piezoelectric composite material array, which is composed of eight such rectangular BCZT / PDMS piezoelectric composite materials. Its main function is to receive vital sign signals. Figure 3 In it, 14 is a flexible material PDMS vest material. This component does not have piezoelectricity. Its main function is to attach the flexible BCZT / PDMS piezoelectric composite material on it to form an array and realize the function of preliminary signal amplification. This array is a 4-row and 2-column rectangular array, and electrode wires are led out from each unit of the array. Among them, the electrode wires connect each flexible material unit to form an array mode of 2 strings in series and 4 in parallel. The series structure makes the output voltage twice that of the unit voltage, while the parallel structure is beneficial to reducing the internal resistance of the sensor, increasing the output voltage of the sensor, and effectively improving the sensitivity of the sensor.

[0034] Figure 4 It is the display of the measurement results on the display interface of the mobile device. This mobile terminal program can receive the signals collected by the sensor in real time and display the real-time breathing condition of the user. The user can understand their respiratory system health condition and vital health condition through this mobile terminal program.

Claims

1. A wearable breath monitoring device based on a flexible piezoelectric thin film material, characterized by, It comprises three modules, specifically, a signal receiving module (1), a signal processing module (2) and a data conversion module (3), the signal receiving module is electrically connected with the signal processing module, and the signal processing module is electrically connected with the data conversion module. The signal receiving module is composed of an array of flexible BCZT / PDMS composite piezoelectric film material, which is used to receive the signal generated by breathing; the array unit in the signal receiving module is connected by electrode wires to form a 2-string 4-parallel combined array mode.

2. A wearable breath monitoring device based on flexible piezoelectric thin film material according to claim 1, characterized in that, The 2-string 4-parallel combined array mode is that eight BCZT / PDMS piezoelectric composite material units are arranged in two columns, four units in each column, one column is connected by wires as positive electrode, and the other column is connected by wires as negative electrode, and one unit of positive electrode is electrically connected with one unit of negative electrode in one-to-one mode; the signal receiving module is located at the chest of the human body, and the whole device can be made into a vest structure, and then the signal receiving module is located at the chest of the human body.

3. A wearable breath monitoring device based on flexible piezoelectric thin film material according to claim 2, characterized in that, The size of the eight BCZT / PDMS piezoelectric composite material units in the signal receiving module is 0.5 cm×1.0 cm, and the thickness is 0.15-0.20 mm.

4. The wearable breath monitoring device based on flexible piezoelectric thin film material according to claim 1, wherein, The upper and lower surfaces of the flexible BCZT / PDMS piezoelectric composite material in the signal receiving module are coated with a silver layer to conduct current and transmit the received vital sign signals to the signal processing module in the form of electrical signals.

5. The wearable breath monitoring device based on flexible piezoelectric thin film material according to claim 1, wherein, The outside of the signal receiving module is packaged by insulating glue to reduce the interference of external electrical signals on the sensing array.

6. The wearable breath monitoring device based on flexible piezoelectric thin film material according to claim 1, wherein, The signal processing module can process the signals received by the signal receiving module. It comprises a preamplifier, a filter, and an analog-to-digital converter (ADC) component.

7. The wearable breath monitoring device based on flexible piezoelectric thin film material according to claim 1, wherein, The data conversion module is composed of a Bluetooth module and a mobile terminal, and transmits the data processed by the signal processing module to the mobile terminal through Bluetooth for data presentation in the mobile terminal.

8. The wearable breath monitoring device based on flexible piezoelectric thin film material according to claim 1, wherein, The Bluetooth MCU is nrf52832, which is developed based on Keil software.

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