Electrostatic induction pendulum for earthquake monitoring and early warning based on electrostatic induction

Abstract

The invention discloses an earthquake monitoring and early warning device based on electrostatic induction, namely an electrostatic induction pendulum. The device comprises a pendulum and an electrostatic induction sensor, and tiny potential changes can be detected in the swinging process. As a core component, the electrostatic induction sensor consists of the following key parts: a weight module, a connecting layer I, an electrode layer, a connecting layer II and an electrostatic interaction layer. Wherein the weight module provides necessary mass so as to ensure the dynamic characteristics of the pendulum; the first connecting layer is used for fixing the connection between the weight module and the electrode layer; the electrode layer is responsible for detecting electrostatic induction signals generated by pendulum motion and converting the signals into measurable potential change; the second connecting layer is used for fixing the electrode layer and the electrostatic interaction layer; the material of the electrostatic interaction layer carries charges, and the electrostatic induction signal of the electrode layer is enhanced in the earthquake monitoring and early warning process. Through the design, the device can realize high-sensitivity monitoring of earthquake precursor, and can capture fine ground movement caused by earthquake waves. In combination with a data acquisition system and a machine learning algorithm, the device can analyze the signals in real time and automatically send early warning information to related departments and individuals when an abnormal vibration mode is detected, so that precious time is won for taking preventive measures.

Description

Technical Field

[0001] The invention relates to the field of earthquake early warning and flexible electronic sensors, and in particular to an electrostatic induction type simple pendulum for earthquake monitoring and early warning based on electrostatic induction. Background Art

[0002] The invention patent "Earthquake Monitoring Device and System" (application number: CN202410584297.4, application publication number: CN118483734A) applied by China State Railway Group Co., Ltd. provides an earthquake monitoring device and system. The device includes a solar power supply unit, a data acquisition unit and a communication unit, wherein the solar power supply unit is electrically connected to the data acquisition unit and the communication unit respectively, and the solar power supply unit is used to supply power to the data acquisition unit and the communication unit; the data acquisition unit includes a MEMS sensor and a positioning module, the MEMS sensor is used to collect earthquake information, and the positioning module is used to obtain the location information of the earthquake monitoring device; the communication unit is electrically connected to the data acquisition unit, and the communication unit is used to wirelessly transmit the earthquake information and the location information to the cloud server. The device has high monitoring accuracy and does not require frequent battery replacement. However, the energy supply of the device depends on solar energy, and in areas with insufficient light, it may encounter the problem of unstable energy supply, so it is greatly affected by the environment. The invention patent "Self-organized earthquake monitoring and early warning method based on emergency information release system" (application number: CN202311147435.4, application publication number: CN117152917A) applied by Taiji Computer Co., Ltd. of China Railway Eryuan Engineering Group Co., Ltd. discloses a self-organized earthquake monitoring and early warning method based on emergency information release system. Its invention arranges multiple monitoring terminals in the monitored earthquake area and selects the main monitoring terminal, determines the main monitoring terminal by election, and merges the seismic wave data detected by the remaining monitoring terminals with the seismic wave data detected by the main monitoring terminal to obtain an intermediate result; the intermediate result is merged with the seismic wave data detected by the monitoring terminal of the upper-level monitored earthquake area to obtain the final result data and transmit it to the emergency information release system to determine whether to trigger an earthquake early warning. Although its invention reduces the communication link between the network center and the emergency information release system, it can further shorten the early warning time. It solves the problem that the existing earthquake monitoring method cannot issue an early warning in a short time due to the long distance between the seismic stations. However, in practical application, it relies on the distribution and collaboration of multiple monitoring terminals, which requires a large investment in infrastructure; when determining the epicenter, it may be affected by the distribution of monitoring terminals and data quality. In order to reduce dependence on infrastructure and improve data quality and the accuracy of epicenter positioning, the invention patent "Real-time co-seismic displacement velocity solution method and system based on Beidou PPP-B2b service" (application number: CN202310699165.1, application publication number: CN116973974A) applied by China University of Petroleum (East China) discloses a real-time co-seismic displacement velocity solution method based on Beidou PPP-B2b service.This method uses the orbit, clock and code deviation corrections broadcast by the BeiDou PPP-B2b service, combined with GNSS observation data, to provide real-time displacement, velocity and acceleration calculations for earthquake monitoring stations without network communication, reducing dependence on widely distributed monitoring terminals. Through precise ephemeris calculation and error correction, the quality of observation data and the accuracy of epicenter positioning are improved, providing a stable and reliable real-time displacement, velocity and acceleration calculation method for GNSS earthquake monitoring stations without network communication in the near field of strong earthquakes. Although its method provides observation data for earthquake monitoring and early warning research, there are still some problems in practical application. Its invention requires specific receivers and processing equipment, which increases the deployment cost and maintenance difficulty of the system, and it relies on the BeiDou PPP-B2b service, which means that if the service fails or is unavailable, it may affect the operation of the entire system.

[0003] Although existing earthquake monitoring methods have made some progress in the detection and early warning of earthquake activities, they still face many challenges and limitations. First, the cost issue is a significant obstacle. The deployment of existing earthquake monitoring systems requires a large amount of hardware equipment, and the purchase, installation and maintenance of these equipment require huge investments. In addition, the operation of the system requires continuous energy supply and technical support, which will also bring additional operating costs. The high cost may limit the popularity of earthquake monitoring systems, especially in economically underdeveloped areas, which may be the areas that most need earthquake early warning capabilities; secondly, the long distance between seismic stations may cause information transmission delays, affecting the timeliness of early warnings; thirdly, existing monitoring technologies may be interfered by environmental noise, affecting the accuracy and reliability of data; finally, the complexity of geological conditions will also affect the propagation of seismic waves, making the interpretation of monitoring data more difficult. In view of these challenges, it has become particularly urgent to develop new earthquake monitoring technologies. Summary of the invention

[0004] In view of the problems of high cost, incomplete coverage and difficulty in deployment in remote areas in the above-mentioned technologies, the present invention proposes an earthquake monitoring and early warning device based on electrostatic induction - an electrostatic induction pendulum.

[0005] The present invention solves the technical problem by adopting a technical solution: an electrostatic induction pendulum for earthquake monitoring and early warning based on electrostatic induction, comprising a conductive cycloid and a pendulum, wherein one end of the conductive cycloid is fixedly connected to the pendulum, wherein the pendulum is cylindrical, the center of the pendulum is a weight module (1), and the outside of the weight module (1) is sequentially connected to a connection layer 1 (2), an electrode layer (3), a connection layer 2 (4), and an electrostatic interaction layer (5); when the conductive cycloid is fixedly connected to the pendulum, a portion of the conductive cycloid is simultaneously connected to the electrode layer (3), and the conductive cycloid is long enough so as not to affect the movement of the pendulum.

[0006] Preferably, the cylindrical model of the weight module (1) is made by 3D printing technology, and its material is polylactic acid.

[0007] Preferably, the effective projection area of ​​the weight module (1) is between 10 and 100 cm 2 The mass is between 10-150 g.

[0008] Preferably, the first connecting layer (2) and the second connecting layer (4) are made of VHB tape, which respectively firmly bonds the weight module (1) and the electrode layer (3), and the electrode layer (3) and the electrostatic interaction layer (5) together.

[0009] Preferably, the electrode layer (3) is made of copper and is used to detect and convert electrostatic induction signals. When external vibrations such as earthquake waves cause the pendulum to move, the relative position between the electrode layer (3) and the spatially distributed charges changes, which causes the electric field distribution to change, thereby generating a potential difference on the electrode layer. This potential difference change is detected by the electrode layer and converted into electrical signals, which are then transmitted to a Keithley 6517B electrometer and a DMM6500 desktop digital touch screen multimeter via wires connected to the electrode layer (3) for further processing and analysis.

[0010] Preferably, the electrostatic interaction layer (5) is made of thermoplastic polyurethane by electrostatic spinning technology. As one of the key materials, thermoplastic polyurethane itself carries static charge, which can effectively enhance the electrostatic induction signal of the electrode layer (3) during earthquake monitoring, thereby providing a reliable signal for subsequent earthquake warning.

[0011] An earthquake monitoring and early warning device, including any of the above-mentioned electrostatic induction pendulums, and also including an electrostatic induction pendulum for earthquake monitoring and early warning based on electrostatic induction, further integrating a data acquisition module and a decision support system. This decision support system is driven by six machine learning algorithms, including K-Nearest Neighbors (KNN), Support Vector Machine (SVM), Decision Tree (DT), Random Forest (RF), Extreme Gradient Boosting (XGB), and Multi-layer Perceptron (MPL). These algorithms work together to realize the real-time acquisition, analysis, and processing of the potential difference signal generated during the movement of the pendulum.

[0012] Compared with the prior art, the present invention has the following beneficial effects: Low cost: The present invention uses cost-effective components and materials, such as using 3D printing technology to make weight modules. This method not only reduces material waste, but also shortens the production cycle and reduces processing costs; it uses widely available copper materials as electrode layers. This material not only has excellent conductivity but also has low cost, further reducing the cost of the entire system. In addition, the present invention also reduces the need for complex electronic components through optimized design, avoids expensive custom components, and makes the entire electrostatic induction pendulum system more economical and practical. This low-cost feature allows the earthquake monitoring equipment of the present invention to be deployed on a large scale, especially in areas with limited economic conditions or earthquake-prone areas, and can provide an efficient and easy-to-popular earthquake early warning solution.

[0013] Simple structure: The electrostatic induction pendulum of the present invention has a simple mechanical structure, is easy to maintain and operate, and reduces failure points and maintenance requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 An overall schematic diagram of the electrostatic induction pendulum device of the present invention.

[0015] Figure 2 Schematic diagram of the layers of the electrostatic induction sensor device, from the inside to the outside, the weight module (1), the connection layer 1 (2), the electrode layer (3), the connection layer 2 (4), and the electrostatic interaction layer (5).

[0016] Figure 3 Schematic diagram of the decomposition of the electrostatic interaction layer (5) in the sensor device.

[0017] Figure 4 Flow chart of earthquake monitoring and early warning based on electrostatic induction. DETAILED DESCRIPTION

[0018] The working principle of the electrostatic induction pendulum device of the present invention is based on the ground movement caused by seismic waves. These tiny movements are captured by the electrostatic induction sensor of the device and converted into electrical signals. When the seismic wave arrives, the weight module of the device will swing due to the vibration of the ground, causing the relative position between the spatially distributed charge and the charge on the electrode layer to change. This position change will produce a changing potential difference on the electrode layer. The copper electrode layer sensitively detects these potential differences and converts them into electrical signals. The electrical signal is then transmitted to the Keithley 6517B electrometer and DMM6500 desktop digital touch screen multimeter data acquisition system through a conductive line, and the data acquisition system is responsible for collecting and preliminarily processing these signals. The processed signal is fed into an integrated machine learning model that is trained to recognize the characteristic patterns of seismic waves. Once a signal pattern related to an earthquake is detected, the system automatically sends an early warning message to a preset recipient, thereby achieving early warning of an earthquake.

[0019] In order to better understand the technical solution of the present invention, it will be described in detail with reference to the accompanying drawings.

[0020] Implementation Example 1: An electrostatic induction pendulum for earthquake monitoring and early warning based on electrostatic induction, comprising a weight module (1), a first connection layer (2), an electrode layer (3), a second connection layer (4) and an electrostatic interaction layer (5). The weight module (1) is made of polylactic acid; the first connection layer (2) and the second connection layer (4) are made of VHB tape; the electrode layer is made of copper; and the electrostatic interaction layer (5) is made of thermoplastic polyurethane.

[0021] Implementation Example 2: The electrostatic interaction layer (5) and the electrode layer (3) in the device are firmly bonded together by the second connecting layer (4), ensuring that the two key layers will not loosen or fall off during long-term use. This design not only ensures the durability of the device, but also ensures that the electrostatic induction signal can be transmitted with high sensitivity and accuracy, thereby improving the response speed and accuracy of the earthquake monitoring and early warning system.

[0022] The implementation principle of the technical solution is further explained as follows: In each part of the sensor, the material constituting the electrostatic interaction layer (5) itself carries an electric charge, which enhances the electrostatic induction signal of the electrode layer (3) during earthquake monitoring and early warning. The selected thermoplastic polyurethane not only has excellent flexibility, wear resistance and oil resistance, but also exhibits good conductivity, making it an ideal choice for making a flexible electrostatic interaction layer. The preparation process first involves dissolving polyurethane particles of appropriate particle size and mass in a specific solvent to form a uniform solution under suitable temperature and stirring conditions. Next, the solution is loaded into a syringe or spinner and electrospun using a voltage of 12 kV, with a flow rate controlled at 0.8 ml / h and the needle tip maintained at a distance of 18 cm from the collector. During the electrospinning process, the thermoplastic polyurethane solution is stretched into fibers, which float in the air and accumulate on the collector to form a flexible nanofiber layer. Finally, the thermoplastic polyurethane film on the collector is gently removed and dried to successfully prepare thermoplastic polyurethane nanofibers.

[0023] The electrostatic induction pendulum consists of an electrostatic induction sensor and a conductive pendulum wire. The first step of assembly is to use a mass of 10.41 g and a projected area of ​​1.5 cm 2 Then, according to different research needs, three groups of models were manufactured by 3D printing technology: the first group of models had an effective projection area of ​​10-100 cm 2The first group of models kept one of the three mass values ​​selected in the first group unchanged, and selected three different values ​​for the effective projected area between 10-100 cm² to study the damping and resonance characteristics of the electrostatic induction pendulum. The sensor was assembled using a 3D printed model as a weight module, VHB tape as an adhesive layer, a conductive copper tape as an electrode layer, and thermal polyurethane nanofibers as a charge supply layer. Finally, the assembled sensor was connected to the conductive pendulum to complete the assembly process of the entire electrostatic induction pendulum.

[0024] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

[0025] Preferably, the cylindrical model of the weight module (1) is made by 3D printing technology. The mass of the weight module affects the inertia of the pendulum, thereby determining the length of time for the oscillation to decay. A larger mass will increase the inertia of the pendulum, prolong the decay time, and provide a longer time window for capturing seismic waves, but will also affect the system's response speed to continuous seismic waves; the projected area of ​​the weight module affects the air resistance, thereby changing the damping coefficient of the pendulum. A larger projected area will increase the air resistance, shorten the decay time, help to quickly stop useless oscillations and prepare to capture the next seismic wave, but may not be conducive to quickly responding to continuous seismic events. By adjusting these parameters, we can optimize the natural frequency of the pendulum to match it with seismic waves of a specific frequency, improve the capture capability, and ensure that the pendulum can quickly return to the equilibrium position after the seismic wave passes, ready to capture subsequent waves. Therefore, three models with different filling densities were made through 3D printing. The effective projection area of ​​each group of models was selected to be a fixed value between 10-100 cm2, and the mass was selected to be three groups of values ​​between 10-150 g. Furthermore, three models with different projection areas were made through 3D printing. Their masses kept one of the three groups of mass values ​​selected in the first group unchanged, and at the same time, the effective projection area was selected to be three different groups of values ​​between 10-100 cm², which met the research requirements of studying the damping and resonance characteristics of the electrostatic induction pendulum.

Claims

1. An electrostatic induction pendulum for earthquake monitoring and early warning based on electrostatic induction, comprising a conductive cycloid and a pendulum, wherein one end of the conductive cycloid is fixedly connected to the pendulum, and characterized in that: The pendulum is cylindrical, the center of the pendulum is a weight module (1), and the outer sides of the weight module (1) are connected layer 1 (2), electrode layer (3), connection layer 2 (4), and electrostatic interaction layer (5) in sequence; when the conductive pendulum is connected and fixed to the pendulum, a portion of the conductive pendulum is also connected to the electrode layer (3), and the conductive pendulum is long enough so as not to affect the movement of the pendulum.

2. The electrostatic induction pendulum for earthquake monitoring and early warning based on electrostatic induction according to claim 1, characterized in that: The cylindrical model of the weight module (1) is made by 3D printing technology, and its material is polylactic acid (PLA), which is a biodegradable thermoplastic polymer with good mechanical properties.

3. The electrostatic induction pendulum for earthquake monitoring and early warning based on electrostatic induction according to claim 2, characterized in that: The effective projection area of ​​the weight module (1) is between 10 and 100 cm 2 The mass is between 10-150 g.

4. The electrostatic induction pendulum for earthquake monitoring and early warning based on electrostatic induction according to claim 3 is characterized in that: The materials of the connecting layer 1 (2) and the connecting layer 2 (4) are Very High Bond (VHB) tapes, which respectively bond the weight module (1) and the electrode layer (3), and the electrode layer (3) and the electrostatic interaction layer (5) together.

5. The electrostatic induction pendulum for earthquake monitoring and early warning based on electrostatic induction according to claim 4, characterized in that: The electrode layer (3) is made of copper.

6. The electrostatic induction pendulum for earthquake monitoring and early warning based on electrostatic induction according to claim 5, characterized in that: The electrostatic interaction layer (5) is made of thermoplastic polyurethane by means of electrostatic spinning technology.

7. An earthquake monitoring and early warning device, comprising the electrostatic induction pendulum according to any one of claims 1 to 6, characterized in that: The electrostatic induction pendulum for earthquake monitoring and early warning based on electrostatic induction further integrates data acquisition modules and decision support systems. This decision support system is driven by six machine learning algorithms, including K-Nearest Neighbors (KNN), Support Vector Machine (SVM), Decision Tree (DT), Random Forest (RF), Extreme Gradient Boosting (XGB), and Multi-layer Perceptron (MPL). These algorithms work together to realize the real-time acquisition, analysis, and processing of the potential difference signal generated during the movement of the pendulum.

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