Piezoelectric cantilever vibration sensing and super capacitor self-powered energy closed-loop operation method and system

Abstract

The invention relates to the field of buried facility monitoring, and discloses a piezoelectric cantilever vibration sensing and super capacitor self-powered energy closed-loop operation method and system, and the method comprises the steps: building a star array composed of a master pile and a slave pile, and configuring a TDMA time slot and an uplink message length; the slave pile collects a vibration signal through a piezoelectric cantilever, the vibration signal is rectified by a piezoelectric rectification energy taking module and then charges a super capacitor, and the voltage state of the two ends of the super capacitor is obtained; when the voltage state reaches a preset upper threshold, the boosting module supplies power to the processing circuit and the transmitting circuit of the slave pile, and the processing circuit generates a four-byte feature code; the slave piles send four-byte feature codes in a magnetic induction link according to TDMA time slots, the master pile receives and aggregates the four-byte feature codes sent by the multiple slave piles, completes positioning and fusion according to the arrival time difference, and returns the four-byte feature codes to the platform through LoRa and 4G, and the platform completes storage and output according to the four-byte feature codes and a positioning result. According to the invention, end-side cloud connection and replicable deployment can be realized, and low-frequency vibration acquisition and buried communication are adapted.

Description

Technical Field

[0001] This invention relates to the field of buried facility monitoring technology, and in particular to a piezoelectric cantilever vibration sensing and supercapacitor self-powered closed-loop operation method and system. Background Technology

[0002] Oil and gas pipelines face multiple risks during long-term service, including mechanical excavation, human-caused damage, and geological disasters such as landslides. In directly buried environments, power supply is difficult, soil significantly attenuates wireless signals, and power frequency electromagnetic interference is prevalent. This makes low-cost, scalable, and battery-free vibration monitoring units an urgent need. Existing solutions often require trade-offs between power supply, connectivity, and continuous monitoring, making it difficult to simultaneously achieve convenient deployment and long-term stability.

[0003] Existing technologies suffer from significant gaps in usability and cost-effectiveness: negative pressure wave monitoring struggles to reliably locate minute leaks; distributed fiber optic systems incur high costs and significant construction disruptions for sections without accompanying optical cables; video and drone monitoring are severely affected by obstructions, weather, and nighttime lighting, resulting in numerous blind spots and high maintenance costs; intelligent cathodic protection only reflects potential changes and is insensitive to mechanical damage and early-stage voids; internal detection methods such as magnetic flux leakage, eddy current, and ultrasound are primarily geared towards periodic inspections and cannot provide continuous real-time early warnings. Furthermore, the strong underground power frequency electromagnetic environment and soil attenuation lead to severe fading of wired and traditional wireless links, and the maintenance burden of power supply and battery replacement makes large-scale deployment unsustainable, creating a practical dilemma where monitoring is possible but widespread deployment is not feasible. Summary of the Invention

[0004] To address the aforementioned issues, the present invention aims to provide a closed-loop operation method and system for piezoelectric cantilever vibration sensing and supercapacitor self-powered energy. The system involves charging a supercapacitor via a PVDF-TrFE cantilever from a pile through rectification, followed by uplink processing and magnetic induction via a boost module. A four-byte feature code is generated for access in TDMA or Mesh. The main pile aggregates multiple slave piles, combining arrival time difference and small model identification, uplinking via LoRa and transmitting back to the platform through mobile communication. This enables GIS visualization and hierarchical alarms, achieving end-edge-cloud connectivity and replicable deployment. A one-main-eight-slave configuration is adopted, with a burial depth of approximately 1.5 meters. The pile body consists of three 6-centimeter sections with screw connections, a concave top surface, and an inner shielding layer using a metamaterial waveguide, making it suitable for low-frequency vibration acquisition and buried communication.

[0005] To achieve the above objectives, in a first aspect, the technical solution adopted by the present invention is as follows: a closed-loop operation method for piezoelectric cantilever vibration sensing and supercapacitor self-powered energy, comprising: establishing a star array composed of master piles and slave piles, configuring TDMA time slots and uplink message lengths; the slave piles collect vibration signals using piezoelectric cantilever, which are then rectified by a piezoelectric rectifier energy harvesting module and used to charge the supercapacitor to obtain the voltage state across the supercapacitor; when the voltage state reaches a preset upper threshold, a boost module supplies power to the processing circuit and transmitting circuit of the slave piles, and the processing circuit generates a four-byte feature code; the slave piles send the four-byte feature code in the magnetic induction link according to the TDMA time slots, the master pile receives and aggregates the four-byte feature codes sent by multiple slave piles, completes positioning and fusion based on the time difference of arrival, and transmits it back to the platform via LoRa and 4G, and the platform completes storage and output based on the four-byte feature code and positioning results.

[0006] Furthermore, vibration signals are collected from the pile using a piezoelectric cantilever, rectified by a piezoelectric rectifier energy harvesting module, and then used to charge a supercapacitor. Specifically: The energy harvesting and power supply link from the pile is formed by sequentially connecting a polyvinylidene fluoride-trifluoroethylene cantilever, an integrated rectifier energy harvesting chip, a supercapacitor, and a boost chip. The polyvinylidene fluoride-trifluoroethylene cantilever converts low-frequency soil vibration into accumulable DC energy, and completes the continuous energy accumulation and steady-state transition required in the battery-free scenario within the integrated rectifier energy harvesting chip, providing the energy baseline and timing baseline for subsequent supercapacitor energy storage and boost chip voltage boosting.

[0007] Furthermore, when the voltage reaches the preset upper threshold, the boost module supplies power to the processing circuit and transmitting circuit of the slave pile. Specifically, the voltage control of the supercapacitor adopts a dual threshold hysteresis strategy with upper and lower thresholds. When the voltage is not lower than the upper threshold, the boost function is activated and the system enters the reporting preparation stage. When the voltage is not higher than the lower threshold, the boost and reporting functions are turned off, and the power-on duration must cover the total processing and transmission time.

[0008] Furthermore, the four-byte feature code consists of a category index field, a frequency band summary field, an energy indicator field, and a check field in a fixed order; the master stake distributes the bit width and order through protocol configuration, and the slave stake generates and caches the four-byte feature code according to the configuration.

[0009] Furthermore, the slave piles send four-byte feature codes in the magnetic induction link according to the TDMA time slots. The master pile receives and aggregates the four-byte feature codes sent by multiple slave piles. Specifically, it performs uplink transmission or one-hop relay according to the configured time slots and addressing overhead, so as to realize the simultaneous completion of vibration sensing and data transmission under the condition of no external power supply. Among them, the magnetic induction uplink adopts a near-field link coupled with ferrite rods, the access adopts time division multiple access and sets preamble, guard interval and addressing overhead, the relay adopts a mesh topology and prioritizes the least number of hops, and if there is an equivalent path, the path with the higher end-to-end success rate is selected.

[0010] Furthermore, the star array composed of main piles and slave piles is arranged in a staggered scattering pattern with one main pile and eight slave piles. The slave piles are buried at a preset depth and maintain a set spacing with the main piles. The main piles are connected by a long-distance low-power wireless network, and the main piles and the platform are connected by mobile communication for backhaul.

[0011] Furthermore, the arrival times of four to eight secondary piles are aggregated within a single cycle of the main pile, and the arrival time difference is verified using a soil sound velocity calibration model. On the edge side, a one-dimensional convolutional small model is used to output the behavioral confidence. The platform fuses events from multiple main piles and multiple time slots according to preset rules.

[0012] Secondly, the technical solution adopted by this invention is as follows: a piezoelectric cantilever vibration sensing and supercapacitor self-powered energy closed-loop system, comprising: a parameter configuration module, which establishes a star array composed of master piles and slave piles, and configures TDMA time slots and uplink message lengths; a slave pile energy harvesting and power supply link, wherein the slave piles collect vibration signals with piezoelectric cantilever, and charge the supercapacitor after rectification by the piezoelectric rectifier energy harvesting module to obtain the voltage state at both ends of the supercapacitor; when the voltage state reaches a preset upper threshold, the boost module supplies power to the processing circuit and transmitting circuit of the slave pile, and the processing circuit generates a four-byte feature code; a cross-layer collaboration module, wherein the slave piles send the four-byte feature code in the magnetic induction link according to the TDMA time slot, the master pile receives and aggregates the four-byte feature codes sent by multiple slave piles, completes positioning and fusion according to the arrival time difference, and transmits it back to the platform via LoRa and 4G, and the platform completes storage and output according to the four-byte feature code and positioning result.

[0013] Thirdly, the technical solution adopted by the present invention is: a computer-readable storage medium for storing one or more programs, wherein the one or more programs include instructions, which, when executed by a computing device, cause the computing device to perform any of the methods described above.

[0014] Fourthly, the technical solution adopted by the present invention is: a computing device comprising: one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, and the one or more programs include instructions for performing any of the methods described above.

[0015] The present invention has the following advantages due to the adoption of the above technical solutions: 1. The master-slave pile star-shaped architecture of this invention, in conjunction with the steel rod shell, top concave surface, acoustic metamaterial waveguide, and μ-metal shield, enhances low-frequency vibration coupling and suppresses power frequency interference, supporting long-term stable operation at a burial depth of approximately 1.5 meters. The slave pile uses a PVDF-TrFE cantilever with LTC3588 rectification, 5F / 5.5V supercapacitor energy storage, and TPS61099 boost to convert discrete vibrations into manageable DC energy, avoiding undervoltage reset and reducing battery replacement maintenance.

[0016] 2. The CH32V003 used in this invention completes vibration feature extraction and outputs a four-byte feature code under energy gating, which significantly reduces the processing and transmission load, and enables timely reporting within the self-powered budget; magnetic induction transmission and relay combined with TDMA adaptive and Mesh ensure conflict-free access and fewer hops for multiple slave piles within a range of 60-85 meters, improving the reliability of direct buried links.

[0017] 3. The main pile of this invention uses triaxial MEMS and dual piezoelectric films to achieve rapid identification in about 200 milliseconds and converge multiple slave piles within a 120-meter radius to achieve point-to-area perimeter coverage; LoRa and 4G backhaul between main piles work together to quickly deliver small packets from the site to the platform, reducing reliance on high-bandwidth infrastructure and taking into account both in-service pipelines and farmland reclamation; the platform integrates 1D-CNN with TDOA and RAG+MCP+LLM to form hierarchical alarms and GIS heat maps for excavation, tunneling, and micro-leakage, and links with sound and light, APP, SMS and automatic reporting. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the closed-loop operation method of piezoelectric cantilever vibration sensing and supercapacitor self-powered energy in an embodiment of the present invention. Detailed Implementation

[0019] To address the challenges of providing continuous real-time early warnings using existing technologies, and the operational burden of power supply and battery replacement making large-scale deployment unsustainable and creating a practical dilemma of being able to monitor but not deploy, a low-cost, self-powered monitoring unit is needed that is designed for low-frequency vibrations in soil, can operate for extended periods in directly buried environments, and forms a closed-loop linkage between the edge and cloud with the upper-level platform to achieve multimodal perception, low-latency alarms, traceable visualization, and standardized reuse. Without laying external power supplies and accompanying optical cables, and without damaging existing pipelines and farmland, how can a scalable real-time alarm capability be built in an environment where direct burial at approximately 1.5 meters is possible, where strong power frequency interference and soil attenuation coexist? This involves location verification based on time difference of arrival and rapid identification using small edge models, followed by long-distance low-power networking and mobile communication to achieve planar splicing and platform backhaul. This ensures message integrity, location reliability, and alarm timeliness even under conditions of simultaneous multi-point triggering, limited bandwidth, and random energy supply. However, if a unified energy closed-loop and hierarchical communication coordination and scheduling mechanism cannot be established in this direct-buried scenario, it will lead to undervoltage reset, link congestion, and a coexistence of false alarms and missed alarms, ultimately causing real-time early warnings to fail and exacerbating environmental and safety risks.

[0020] Therefore, this invention provides a closed-loop operation method and system for piezoelectric cantilever vibration sensing and supercapacitor self-powered energy. Addressing the challenges of achieving real-time alarm, low-cost large-scale deployment, and reliable data transmission under conditions of no external power supply, strong power frequency interference, and soil attenuation, this invention proposes a self-powered energy closed-loop and hierarchical communication scheme using a master-slave pile star topology: The slave piles use a PVDF-TrFE cantilever to charge the supercapacitor via rectification, then a boost module drives processing and magnetic induction uplink, generating a four-byte feature code for access in TDMA or Mesh; the master pile aggregates multiple slave piles, combining arrival time difference and small model identification, uplinking via LoRa and transmitting back to the platform via mobile communication, completing GIS visualization and hierarchical alarms, achieving end-edge-cloud connectivity and replicable deployment. The system employs a one-master-eight-slave deployment, with a burial depth of approximately 1.5 meters, a 6-centimeter three-section screw-connected pile body, a concave top surface, and a metamaterial waveguide for inner shielding, adaptable to low-frequency vibration acquisition and buried communication.

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0022] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0023] In one embodiment of the present invention, a closed-loop operation method for piezoelectric cantilever vibration sensing and supercapacitor self-powered energy is provided. In this embodiment, as... Figure 1 As shown, the method includes the following steps: 1) Establish a star array consisting of master and slave nodes, and configure TDMA time slots and uplink message length; 2) Vibration signals are collected from the pile using a piezoelectric cantilever. After being rectified by the piezoelectric rectifier energy harvesting module, the signals are used to charge the supercapacitor and obtain the voltage state across the supercapacitor. When the voltage state reaches the preset upper threshold, the boost module supplies power to the processing circuit and the transmitting circuit of the pile, and the processing circuit generates a four-byte feature code. 3) The slave pile sends a four-byte feature code in the magnetic induction link according to the TDMA time slot, and forwards it through the slave pile relay if necessary; the master pile receives and aggregates the four-byte feature codes sent by multiple slave piles, completes the positioning and fusion according to the time difference of arrival, and transmits it back to the platform via LoRa and 4G. The platform completes the storage and output according to the four-byte feature code and the positioning result.

[0024] In step 1) above, the star array composed of main piles and slave piles is arranged in a staggered scattering pattern with one main pile and eight slave piles. The slave piles are buried at a preset depth and maintain a set spacing with the main piles. The main piles are connected by a long-distance low-power wireless network, and the main piles and the platform are connected by mobile communication.

[0025] In this embodiment, the arrival times of four to eight slave piles are aggregated within a single cycle of the main pile, and the arrival time difference is verified using a soil sound velocity calibration model. On the edge side, a one-dimensional convolutional small model is used to output the behavioral confidence. The platform fuses the events of multiple main piles and multiple time slots according to preset rules.

[0026] Among them, the soil sound velocity calibration model, for ease of time difference positioning, refers to a parameterized model constructed based on field geometry and arrival time observations. This model is used to estimate and update soil sound velocity and clock offset, and to perform online corrections when temperature, humidity, burial depth, or soil layer changes occur. Its basic relationship is as follows:

[0027] Wherein: Time difference of arrival : No. , Predicted time difference of arrival (TDOA) for the same event at each receiving point; geometric path difference The difference in the propagation path length from the event to the two receiving points; the speed of sound in the soil. : State vector with environment Effective propagation speed of changes (such as moisture content, temperature, burial depth / layered tags); clock offset The residual synchronization bias between the two receiving points.

[0028] The soil sound velocity calibration model generates samples from a calibration impact source with known coordinates or a locatable typical event. Simultaneous solution using least squares / robust estimation and The data is stored in a lookup table for "Sound Speed ​​- Working Condition" by layer or partition, and then used for subsequent TDOA calculation and consistency verification.

[0029] Furthermore, the pile body is a composite shell with a diameter of six centimeters and three-section threaded connection, and a wall thickness of one millimeter. The top is concave, the bottom is equipped with a conical resonator and connected to an acoustic metamaterial waveguide, the inner layer is coated with a high magnetic permeability shielding layer, and the outer shell meets IP68.

[0030] This embodiment employs a master-slave star array, typically with one master and eight slave piles. The slave piles are buried at a depth of approximately 1.5m, using a PVDF-TrFE cantilever as the piezoelectric transducer core and also serving as a vibration sensing element, requiring no external power source. The master pile is located at the geometric center or boundary convergence point of the array, housing a triaxial MEMS and dual piezoelectric thin films for local identification and multi-slave pile fusion. The array's geometric parameters, TDMA time slots, and reported load lengths are transmitted from the master pile and recorded on the platform.

[0031] The secondary pile is a 60mm diameter bullet-shaped column, driven into the soil using a three-section screw-in tail rod. The internal cavity, arranged from top to bottom, includes: a concave coupling end at the top, a metamaterial waveguide and conical resonator, a piezoelectric cantilever and energy management chamber, and a magnetic induction transmitter / relay chamber. The inner wall is equipped with a high-permeability shielding layer to suppress power frequency interference. The outer shell meets IP68 standards. The main pile shell and installation method are consistent with or reinforced with those of the secondary piles, facilitating unified construction and maintenance.

[0032] The PVDF-TrFE cantilever of the pile outputs AC current under the excitation of low-frequency vibration in the surrounding area. The front end uses LTC3588 to complete full-wave rectification and energy capture, guiding the AC energy to the energy storage bus. A high-impedance sampling branch is configured on the input side to facilitate reading the vibration window signal without affecting the rectification. A voltage limiting network is set between the rectification node and the energy storage bus to prevent transient overvoltage.

[0033] A 5F / 5.5V supercapacitor is connected to the energy storage bus as an energy sink; the subsequent stage uses a TPS61099 boost converter for low-power processing and magnetic induction transmission / relay power supply. Energy dispatch employs a dual-threshold hysteresis threshold and sustainability constraint: when the supercapacitor voltage reaches the upper threshold, boosting is allowed and reporting preparation begins; when the voltage falls below the lower threshold, boosting is shut down and the system enters sleep mode to recharge; the sustainability duration must cover the feature extraction time plus the transmission time. Threshold values, duty cycles, and time slot configurations are uniformly issued by the main pile / platform.

[0034] When energy permits, the CH32V003 microcontroller performs lightweight processing on the window signal from the pile, and the resulting feature is reported as a fixed-length 4-byte feature code.

[0035] The connection from the main pile to the master pile uses a magnetic induction near-field link with a ferrite rod antenna. Access employs TDMA adaptive switching. To avoid conflicts within the same group, the master pile transmits time slots, protection intervals, and addressing overhead. When the direct link is blocked, Mesh relay is activated, prioritizing the path with the fewest hops, and selecting the path with the higher end-to-end success rate when equivalence is involved. LoRa is used for inter-group splicing between master piles, and data is transmitted back from the master pile to the platform via mobile communication.

[0036] Within a single cycle, the main pile aggregates 4-8 slave pile messages and reads the results from the local triaxial MEMS and dual piezoelectric films. The positioning is verified using a calibration model with a time difference of arrival and a sound velocity in the soil of approximately 200 m / s. On the edge side, a one-dimensional convolutional small model is used to output behavioral confidence. On the platform side, the small packet data and edge results are aggregated into the GIS, and alarms are triggered by sound and light, APP, and SMS according to the hierarchical rules, and a perimeter activity report PDF is generated. The platform saves network parameters, thresholds, and link quality metadata for auditing and maintenance.

[0037] This invention clearly distinguishes between the parallel signal domain and the energy domain: within any window period, vibration disturbances are converted into two paths—a measured quantity and an energy quantity—by a piezoelectric cantilever. The former is sampled through high impedance and enters a lightweight characteristic operator and a fixed-length quantization mapping, while the latter is rectified by piezoelectric current and energy captured and accumulated to a supercapacitor, then supplied by a boost unit for processing and near-field emission. The two paths share the same transducer but are electrically decoupled from each other to ensure stable coordination between the sensing link and the energy harvesting link.

[0038] In this embodiment, specifically for long-term direct burial, energy-constrained, and strong power frequency interference environments, step 1) mainly involves integrating the mechanical structure, vibration sensing, edge processing, and hierarchical communication of the master pile-slave pile star array within a unified parameter domain. This ensures that subsequent energy harvesting, energy storage, and small packet reporting operate stably in a closed loop within predetermined time delay and coverage indicators, and ensures that the engineering chain of deployment, identification, and backhaul is reusable and verifiable. An integrated constraint and interface specification based on master piles and slave piles is constructed. The pile structure (Ø60mm three-section thread, 1.2mm wall thickness, μ metal shielding, IP68), vibration sensing (master pile triaxial MEMS + dual piezoelectric film, slave pile piezoelectric film), edge processing (CH32V003 output 4-byte feature code) and layered communication (short-range magnetic induction, long-range LoRa / 4G) are coupled in a unified geometry-timing-message three-domain, thereby meeting the scenario requirements of 200ms recognition, positioning error ≈5m, master pile radius ≈120m, 1 master with 8 slaves, r=60m, D=240m.

[0039] Along the pipeline trench and in high-consequence areas, the traditional approach of single-point sensing, centralized power supply, and unified communication is insufficient to simultaneously meet the comprehensive constraints of a burial depth of approximately 1.5m, strong 50Hz electromagnetic interference, agricultural restoration, and all-weather operation and maintenance. Therefore, it is necessary to define the structural low-frequency coupling enhancement (top concave surface + acoustic metamaterial waveguide), interference-resistant shielding (μ metal liner), star-shaped geometric coverage (1 master and 8 slaves), small packet messages (4-byte signature), short-range magnetic induction, and long-range LoRa / 4G as a continuous engineering closed loop. This ensures that the mechanical, signal, and communication chains are parameter-interlocked during the design phase, avoiding repeated trade-offs in energy and bandwidth later on.

[0040] Firstly, the determinism of the structural domain ensures the accessibility of the signal domain and the reachability of the communication domain. The main pile shell is a Ø60mm shell with a wall thickness of 1.2mm, constructed from segmented alloy and composite materials. A conical resonator is embedded at the bottom and superimposed with an acoustic metamaterial waveguide to enhance low-frequency vibration transmission, while the concave surface at the top improves the incident coupling of ground vibration. An inner layer is coated with a μ-metal shielding layer to suppress 50Hz power frequency interference. The entire pile achieves an IP68 (-40°C~85°C) rating, ensuring long-term stability of the structure-environment interface. This structural domain constraint enables the main pile vibration identification to close within 200ms, with a positioning error controlled to approximately 5m. Simultaneously, it provides a stable and low-noise base for multi-source fusion in the signal domain (main pile triaxial MEMS + dual piezoelectric thin film, slave pile piezoelectric thin film).

[0041] Then, a feasibility criterion for the star array is established in the geometric domain to ensure that coverage and both ends of the link are satisfied simultaneously. Based on a main pile radius of 120m, a conventional main pile spacing of 240m, and a magnetic induction communication and sensing range of 60–85m from the pile to the main pile, the following criterion is defined:

[0042] Among them, communication radius The maximum reachable distance of a short-range magnetic induction link. This is used to constrain accessibility from the pile to the main pile; the distance from the pile to the main pile. : No. The actual distance from the pile to its corresponding main pile. Used for point-to-point accessibility checks; main stake coverage radius The effective detection radius of the main pile for vibration events, typically approximately [value missing]. Used for area coverage verification; main pile spacing The geometric spacing between adjacent main piles, commonly used values ​​are approximately Used for seamless coverage verification of group splicing.

[0043] When comprehensive criteria At this time, the characteristics of reachability from one pile to another and seamless splicing between piles to another are simultaneously satisfied, thus ensuring geometric and link-end consistency and guaranteeing that the star array can effectively collect data and stably transmit it back. By using a single criterion, the two types of constraints, coverage and reachability, are converged to the same decision surface, reducing multi-objective conflicts during deployment.

[0044] Subsequently, edge processing and near-range access are unified in the message timing domain to ensure that energy-information coupling is not broken due to protocol switching. It is agreed that a 4-byte signature code is generated from the stub using CH32V003 when the energy threshold is met, and TDMA adaptive time slots are used for uplink. The reporting load density is defined as follows:

[0045] Among them, message length The characteristic load reported from the pile is fixed as follows: Used to characterize the minimum energy and latency requirements for a single report; TDMA time slot The dynamic allocation of time slot length for magnetic induction access. It is used to ensure conflict-free access of the same group of slave piles.

[0046] When load density When matched with magnetic induction access capabilities, the star array achieves stable injection of small packets into the main pile buffer without increasing energy consumption or protocol overhead. Subsequently, the main pile transmits the packets back to the platform via LoRa networking and 4G. The energy budget of small packet reporting is bound to the access capacity using low-dimensional parameters of message-time slot, avoiding congestion or wasted time slots under self-powered power consumption budget.

[0047] Ultimately, a coherent interface is formed in the sensing-processing-feedback process: the main pile completes vibration identification with triaxial MEMS and dual piezoelectric films and generates event markers within 200ms; the slave piles collect vibrations with piezoelectric films under the same star topology and form 4-byte feature codes; after the main pile integrates the data of 4-8 slave piles, it completes inter-group splicing with LoRa and aggregates to the cloud via 4G.

[0048] This process can be replicated and implemented within an engineering boundary with a Ø60mm shell, 1.2mm wall thickness, μ metal shielding, IP68 rating, 1 master and 8 slaves, r=60m, D=240m, and a burial depth of approximately 1.5m. It also achieves a >92% recognition rate for excavation behavior at a 60m spacing, meeting the real-time early warning requirements for both planar and perimeter scenarios.

[0049] The continuous link description ensures that the input (pile body and sensing structure), processing (feature generation and satellite fusion), and output (main pile back transmission) are interconnected, forming a verifiable integrated baseline.

[0050] In step 2) above, vibration signals are collected from the pile using a piezoelectric cantilever, rectified by the piezoelectric rectifier energy harvesting module, and then used to charge the supercapacitor. Specifically: The energy harvesting and power supply link from the pile is formed by sequentially connecting a polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) cantilever, an integrated rectifier energy harvesting chip, a supercapacitor, and a boost chip. The PVDF-TrFE cantilever converts low-frequency soil vibration into accumulable DC energy, and the integrated rectifier energy harvesting chip (e.g., LTC3588) completes the continuous energy accumulation and steady-state transition required for battery-free scenarios, providing energy and timing baselines for subsequent supercapacitor energy storage, boost chip (e.g., TPS61099) voltage boosting, and 4-byte signature reporting. The supercapacitor is a 5-farad, 5.5-volt rated supercapacitor, and the boost chip is a low-static-power boost chip; the processing circuit is a low-power microcontroller.

[0051] In this embodiment, under the boundary of 1 master and 8 slave piles, a burial depth of about 1.5m, a short-range magnetic induction of 60-85m, and a main pile radius of ≈120m, an integrated energy connection is constructed between the slave pile PVDF-TrFE cantilever and the LTC3588 rectifier capture, so that a single soil vibration can be stably converted into the available charge increment of the supercapacitor, and a definite coupling is formed with the subsequent TDMA small packet reporting time slot.

[0052] Since the top concave surface and acoustic metamaterial waveguide are locked to enhance low-frequency incidence, and μ-metal shielding suppresses 50Hz power frequency interference, the effective vibration incidence-piezoelectric conversion-rectification capture efficiency-supercapacitor voltage increment must be converged to a single evaluable quantity. This avoids a perceptible but unpowerable disconnect when there is no battery energy budget. To this end, this embodiment uses a PVDF-TrFE cantilever as a piezoelectric power generation unit, and its output is directly coupled to the rectification / energy capture input of the LTC3588. Through this front-end energy harvesting path, AC energy is stably injected into the subsequent supercapacitor (5F / 5.5V), thus forming a natural connection with energy storage-boost.

[0053] Specifically, the process unfolds as a single chain of acquisition window - energy integration - voltage increment - trigger criterion: First, an acquisition window matching the target event is selected from the pile side, so that the current and voltage output by the PVDF-TrFE cantilever are efficiently taken over by the LTC3588 within this window; then, the usable energy after rectification is obtained by energy integration; then, this energy is mapped into a definite increment of the supercapacitor voltage; finally, this voltage increment supports the timing organization of subsequent voltage boost and small packet reporting.

[0054] To ensure energy balance closure, the energy integral captured by rectification is defined as follows:

[0055] Among them, rectified capture efficiency Energy efficiency coefficient of LTC3588 rectification / capture link, value range Used to characterize the energy retention from AC to DC; piezoelectric terminal current PVDF-TrFE cantilever output current, the range of which is determined by the actual vibration amplitude, in amperes (A), used to represent the vibration intensity; piezoelectric terminal voltage. : Output voltage of PVDF-TrFE cantilever, in V, used to represent instantaneous energy potential; acquisition window : The energy convergence time window set for the target event, with a value of It is used to couple the TDMA reporting rhythm.

[0056] The randomness of vibrational incident is compressed into an integrable scalar. This ensures that downstream applications perceive only a definite energy increment rather than a complex waveform. The state evolution after rectified energy is injected into the supercapacitor can be written as a voltage increment mapping:

[0057] Among them, supercapacitor voltage : Voltage at the end of the acquisition window, in volts (V), used to measure the instantaneous level of available energy; initial voltage. : Voltage at the supercapacitor terminals at the start of the data acquisition window, in volts (V), reflecting the historical cumulative state; Supercapacitor capacitance value. Core capacitor for energy storage, typical fixed value It has a rated voltage of 5.5V and is used to map energy into voltage; rectification captures energy. The energy obtained from the above formula is expressed in J.

[0058] By projecting the rectified energy directly onto a measurable voltage using a closed-form analytical approach, a consistent interface is established with boost triggering and power management thresholds. To ensure deterministic coupling with subsequent TDMA small packet reporting, an energy triggering criterion is established:

[0059] Among them: TDMA time slot : The value is taken from the time slot length of the pile connection. Consistent with the access organization in step one; energy threshold : The minimum energy required for the pile to complete one power-on-sampling-buffering cycle, measured in J, to ensure that it will not reset due to insufficient power in the absence of a battery; rectified capture energy. : The rectified energy that can be accumulated in a single time slot, in J.

[0060] By using threshold relationships to link energy availability with communication rhythm, it is ensured that small packet reporting is only triggered within the sustainable energy budget, thus avoiding impact on downstream energy storage.

[0061] In terms of engineering implementation, the PVDF-TrFE cantilever is used as the energy harvesting core for the piles, and the LTC3588 is used at the front end to complete rectification / energy capture, and the back stage is a directional supercapacitor (5F / 5.5V); low frequency incident is enhanced by a top concave surface + acoustic metamaterial waveguide, and power frequency disturbance is suppressed by μ metal shielding; the whole is still operating within the layout and communication boundaries of 1 main pile and 8 slave piles, a burial depth of about 1.5m, a short-range magnetic induction of 60-85m, and a main pile radius of ≈120m.

[0062] Through the aforementioned energy integration, state mapping, and triggering criteria, vibration events are transcribed into measurable voltage increments and schedulable time-slot triggers, ultimately providing an energy interface with the same semantics for energy storage-boost in step three and small packet reporting in step four. This is achieved using a parameter family with minimal degrees of freedom. Complete cross-domain alignment from the physical layer to the protocol layer to avoid policy drift in battery-free systems.

[0063] In step 2) above, when the voltage reaches the preset upper threshold, the boost module supplies power to the processing circuit and transmission circuit of the slave pile. Specifically, the voltage control of the supercapacitor adopts a dual threshold hysteresis strategy with upper and lower thresholds; when the voltage is not lower than the upper threshold, the boost is turned on and the reporting preparation begins; when the voltage is not higher than the lower threshold, the boost and reporting are turned off, and the power-on duration must cover the total processing and transmission time.

[0064] In this embodiment, the four-byte feature code consists of a category index field, a frequency band summary field, an energy indicator field, and a check field in a fixed order; the master pile sends the bit width and order through the protocol configuration, and the slave pile generates and caches the four-byte feature code according to the configuration.

[0065] In this embodiment, which is geared towards battery-free slave piles, the goal is to stably deposit the output rectified energy through a supercapacitor (5F / 5.5V) without changing the devices and deployment, and then boost it by the TPS61099 to provide manageable DC power for the vibration sensing-edge processing-magnetic induction transmission link. This enables continuous energy harvesting, energy storage, and power supply in both the timing and energy domains, while meeting the reporting rhythm and reliability requirements of the star array.

[0066] An integrated energy dispatching system combining supercapacitor energy storage and TPS61099 boost power supply is constructed, enabling discrete energy pulses captured by LTC3588 rectification to be transcribed into a controllable continuous power-on duration, thereby achieving stable coupling with subsequent TDMA time slots and 4-byte feature code reporting.

[0067] Without battery constraints, vibration events are random and intermittent. Directly driving the load can easily lead to undervoltage reset and message loss. Therefore, supercapacitor energy storage is needed as an energy buffer. The rectified and captured energy is first deposited into a defined voltage increment, which is then boosted by the TPS61099 within a controlled threshold. This creates an accumulation-release rhythm in the energy domain and a start-stop-maintenance window in the time domain. Ultimately, this ensures that the minimum energy required for a single report is guaranteed and reserves a margin for the next time slot.

[0068] The process unfolds as a single chain based on available energy, power-on duration, threshold hysteresis, and duty cycle mapping, ensuring that each step can be directly invoked by the next step. First, available energy is used to unify rectified deposition with historical reserves.

[0069] In the formula, the supercapacitor can use energy The unit J is used to quantify the total energy currently available for release. The capacitance value of a supercapacitor Fixed at 5F, used for energy-voltage mapping. Supercapacitor voltage Voltage measured in volts (V) at the moment of data acquisition. Minimum allowable voltage : The lower limit threshold for maintaining boost input, in V. ; Rectification captures energy : From the time window energy integral, in J, By converting historical voltage and newly acquired energy into a single usable energy source, it is easier to coordinate and dispatch energy sources in the future without having to distinguish between them.

[0070] After obtaining usable energy, the duration of power-up during the boost phase is written as follows:

[0071] In the formula, the duration of power-on is... Unit: seconds (s), used to plan the maximum time window for a single continuous operation. Boost efficiency The TPS61099's energy efficiency coefficient from input to output. Average load power The combined average power of vibration sensing, edge processing, and magnetic emission, in W. Static power loss Static power consumption of the boost and energy storage link, in W. .

[0072] A direct energy-time mapping is provided based on energy conservation, and boost losses are incorporated into a unified denominator, allowing for precise estimation of power-up duration. To avoid frequent start-stop cycles near edge voltages, a threshold hysteresis-start-stop law is defined and aligned with the TDMA time slot.

[0073] Among them, boost enable state : Binary switch quantity, 1 indicates that boost power supply is allowed, 0 indicates that it is prohibited. Upper threshold voltage : The upper threshold for triggering boost, in units of V. Lower threshold voltage The lower threshold for stopping voltage boost, in units of V. The state at the previous moment : The on / off state of the previous decision cycle, dimensionless; duty cycle This cycle can occupy the time share of TDMA uplink. ; TDMA slots To standardize the time slot length, the unit is seconds (s). By constraining when the hysteresis switch is activated and by constraining how many time slots are available using duty cycle mapping, the energy domain and the access domain can be seamlessly stitched together.

[0074] Rectification and capture are handled by the LTC3588, energy storage is provided by a supercapacitor (5F / 5.5V), and boosting is provided by the TPS61099. The final output is characterized by a three-element diagram of sustainment duration, duty cycle, and start / stop status, and is transmitted to the small packet for scheduling. When available energy increases, it is processed... The linkage expands the reporting window; when energy is tight, hysteresis suppresses jitter and automatically shrinks the duty cycle, ensuring the integrity of a single message while reserving energy margin for the next cycle.

[0075] In this embodiment, the CH32V003 chip is used in the processing circuit on the slave pile side to perform low-power extraction of vibration characteristics and encoding of 4-byte payloads, and reliable injection is completed within the uplink time slot of the magnetic induction TDMA. The available energy-power-on duration-start / stop state-duty cycle are converted into a unified criterion of processing duration-transmission duration-enablement indication, ensuring that the small packet reporting under self-powered conditions is both complete and timely. The generation of vibration characteristics and small packet reporting of the slave pile are constrained by the same energy-timing interface, thereby forming a stable coupling with the supercapacitor-boost output and avoiding underpowered reset or time slot tearing.

[0076] Since the pile is located at a depth of approximately 1.5m and has no battery, it can only operate in the given start-stop state. Power-on duration Duty cycle Working within the window; therefore, the effective compression of vibration segments, the determination and mapping of characteristic quantities, and the fixed-length transmission of loads must be organized into a single chain, so that processing-encoding-transmission and energy-time slot-duty are aligned one by one; thus, the event prompt from pile to main pile is completed with minimal processing and transmission costs, leaving energy and time margin for the fusion of multiple slave piles on the main pile side and subsequent identification.

[0077] The process unfolds using a concatenated approach: window selection, robust features, fixed-length encoding, and time-slot mapping. First, starting from the pile, the piezoelectric film window signal is used as input. The CH32V003 executes only lightweight operators directly related to event differentiation, ensuring the processing time conforms to the energy window. The processing time formula from the pile edge is defined as follows:

[0078] In the formula, the pile treatment time : The time required to complete one feature extraction, in seconds, with a value of Used to align the power-on window; edge workload Total number of operations within the window (number of operators), dimensionless, range of values. Used to measure algorithm complexity; effective throughput The equivalent operational throughput (operators / second) of CH32V003 at the target frequency and in a low-power configuration is given by the following values. It is used to convert algorithmic quantities into time.

[0079] Characterizing the deterministic relationship between computing power and time with minimum degrees of freedom makes processing possible. Direct constraints. Subsequently, the window signal is mapped to a fixed-length load. Defined as a code relationship:

[0080] In the formula, the 4-byte feature code : Fixed-length load output from the pile, with a fixed bit width of 32 bits, used for rapid aggregation of main piles; Feature operator : Robust transformations for event differentiation (such as combinations of band energy clusters / envelope peak sequences) to resist environmental disturbances; Specific form of the characteristic operator F(·) (lightly calculated from the pile side); Preprocessing: for window signals Perform DC removal and bandpass (the frequency band is configured by the protocol table, such as low / medium / high / ultra-low bands).

[0081] Frequency domain statistics: Calculating the amplitude spectrum According to four configuration frequency bands Accumulated to obtain energy Proportional characteristics: Take two sets of dimensionless ratios. , (Values ​​in the range of 0–1), Energy scalar: derived from the analytic signal envelope. Get window energy scale Then, it is linearly normalized to 0–1 according to the upper and lower limits given by the platform; Category index: from four energy segments Take the main peak frequency band number And mapped to category slots 0–63 (leaving room for protocol-extendable categories); in summary, the definition is:

[0082] Quantization mapping : Compresses continuous features into a fixed-length bit string mapping, with a fixed output of 32 bits; Specific form of the quantization mapping Q(·) (fixed-length 4-byte packing); Quantizer: performs uniform quantization on real numbers 0–1. Field and bit width (32 bits in total): Category index C: 6 bits (0–63), by Provided directly; Band summaries R1 and R2: 5 bits each. , Energy indicator A: 8 bit CRC8 checksum: 8 bits, polynomial expression applied to the first 24 bits. Calculation, byte / bit layout (most significant bit first):

[0083] Output:

[0084] Here, `pack` is a packetization operation that concatenates the data into 4 bytes according to the above bit order. The frequency band boundaries, normalization upper and lower limits, and CRC polynomial are all configurable within the protocol configuration table; the bit width is fixed at 6+5+5+8+8, and the master stump can be parsed according to the same table. In this way, F(·) and Q(·) correspond one-to-one, allowing direct inclusion in the 4-byte reporting implementation, and the window signal... : The discrete sequence of piezoelectric thin films within the decision window.

[0085] A two-level mapping is used to compress arbitrary-dimensional features into a unified 4-byte interface, ensuring a constant message length and alignment with the protocol layer. Finally, the transmission timing of the payload in the magnetic induction uplink channel must simultaneously comply with power-on duration and duty cycle constraints. Transmission duration and time slot constraints are defined as follows:

[0086] In the formula, launch duration : Time required to send a 4-byte payload, in seconds. Message length Fixed-length payload bit depth, fixed at 32 bits, used to constrain minimum transmission time; physical layer rate. : Effective bit rate of magnetic induction uplink, value Duty cycle The given TDMA available share, with a value of [value missing]. TDMA time slot Uniform uplink timeslot length, with a set value. .

[0087] This ensures that the transmission time is contained within a defined time slot share, avoiding conflicts with slave stubs in the same group. To unify the triggering conditions, the three constraints of energy, time, and time slot are compressed into a single enable indication:

[0088] In the formula, the enable instruction is reported. : Binary quantity This indicates that reporting is permitted for this period. Indicates prohibition; start / stop status. Given the hysteresis switch, its value is... From the pile processing time Launch duration Power-on duration Used to ensure that processing and transmission are not interrupted; duty cycle TDMA time slots Indicator functions : Take 1 if the condition is true, otherwise take 0.

[0089] The three-domain constraints are merged using a single Boolean value, allowing direct calls from the protocol stack to form a closed-loop decision-making process encompassing prior energy, real-time time slots, and small packet coding. Slave nodes generate 4-byte signatures using a piezoelectric film and CH32V003, which are then transmitted via magnetic induction / relay to the master node, supporting TDMA adaptation and Mesh organization. The master node integrates data from 4–8 slave nodes, uplinks LoRa, and transmits back via 4G. Through this integrated approach, small packet reporting is no longer separated from energy management but is integrated with energy flow and access flow on the same clock plane.

[0090] In step 3) above, the slave pile sends a four-byte feature code in the magnetic induction link according to the TDMA time slot. The master pile receives and aggregates the four-byte feature codes sent by multiple slave piles. Specifically, it performs uplink transmission or one-hop relay according to the configured time slot and addressing overhead, so as to realize the simultaneous completion of vibration sensing and data transmission under the condition of no external power supply. Among them, the magnetic induction uplink adopts a near-field link coupled with ferrite rods, the access adopts time division multiple access and sets preamble, guard interval and addressing overhead, the relay adopts a mesh topology and prioritizes the least number of hops, and if there is an equivalent path, the path with the higher end-to-end success rate is selected.

[0091] In this embodiment, the access capability of the magnetic induction transmitter / relay (ferrite rod) on the pile side within a burial depth of approximately 1.5m and an reachable boundary of 60–85m is integrated with the LoRa network and 4G backhaul on the main pile side to form an energy-constrained but timing-determined hierarchical channel. This allows the 4-byte feature code to be stably injected and reliably transmitted to the platform within the TDMA adaptive time slot, consistent with the 1-master 8-slave star geometric constraint. A unified scheduling law is established for magnetic induction access-relay Mesh-LoRa aggregation-4G backhaul, and the start / stop status output in the previous step is used to control the connection between the magnetic induction access, relay mesh, LoRa aggregation, and 4G backhaul. Power-on duration Duty cycle Launch duration Report enable instructions The mapping is implemented as access admission, forwarding sequence and backhaul timing, thereby avoiding underpowered reset and group conflicts, and realizing energy-timing-multi-hop three-domain coordination.

[0092] Underground magnetic induction links can penetrate soil within a range of 60–85m, but their energy and bandwidth are limited. If duty cycles and time slots are not bound together, congestion and retransmissions will occur without a battery, amplifying energy consumption. Therefore, TDMA adaptively generates allocable time slots at the main pile side first, and then uses uplink enable indicators reported from the pile side. Precise triggering; when individual slave piles are obstructed by terrain, relay mesh is activated to transmit data within one or fewer hops; after the master piles complete batch aggregation, LoRa is used to splice a planar coverage between the master piles, and finally, 4G is used to backhaul to the platform. This bottom-up scheduling chain resolves the three bottlenecks of access conflict, spatial obstruction, and wide-area backhaul in turn.

[0093] Cross-layer collaboration is achieved through a single-chain architecture that models access capacity and achieves end-to-end reliability and latency convergence. First, the upper limit on the number of members that can be accessed and reported within the same group is given:

[0094] Among them, the upper limit of the number of reports that can be accessed : Upper limit of the number of reports allowed from piles within a single time slot; value is a non-negative integer; duty cycle TDMA available share TDMA time slot The length of the uplink time slot shared by the same group. Launch duration Time required to send a 4-byte signature. Channel overhead duration The sum of preamble, guard interval, and addressing overhead. .

[0095] By unifying duty cycle, time slot, and message duration using a closed upper bound, the master node makes admission decisions based on this, thereby ensuring energy and bandwidth matching. Then, the success rate and latency of access, forwarding, and backhaul are unified and converged.

[0096] Among them, end-to-end success rate The success rate of reporting to the platform during this period. Report enable instruction Synthetic energy-time-slot gating, relay hop count : Hop count for magnetic induction mesh forwarding Single hop success rate : No. Probability of successful magnetic link jump LoRa success rate : Success rate of LoRa link between main piles 4G success rate : Probability of successful 4G backhaul from the main pile to the platform ; End-to-end delay Total latency from sampling to arrival at the platform. From the pile processing time : Defined feature extraction time, Single-hop forwarding duration : No. Redirection time LoRa forwarding duration Time consumed for forwarding between main piles 4G backhaul time The time it takes to send the data back to the platform. .

[0097] By employing a product-summation structure to converge energy gating, Mesh forwarding, and LoRa / 4G backhaul to measurable success rates and latency, dynamic scheduling and relay selection at the master pile side are facilitated. Therefore, group scheduling is limited by the maximum access limit. Arrange the piles to meet the distance requirements from the main pile. (60–85m) direct connection afterwards; for individual For stakes that are close to the boundary or obstructed, use the minimum... The principle is to select a relay; LoRa is used on the main pile side. and The process ensures inter-group convergence during splicing, ultimately enabling 4G outbound communication. This procedure aligns with the engineering configuration of a five-pile star array buried at approximately 1.5m depth, avoiding the separation of energy and protocol, and providing bounded mechanisms for fusion discrimination. and .

[0098] In this embodiment, focusing on main pile fusion, cloud-based judgment, hierarchical alarm, and report output, the 4-byte feature code reported by the pile is fused with the local identification result of the main pile, TDOA positioning, and link quality within the same confidence domain. This triggers audio-visual and APP / SMS alarms on the B / S side, and generates an overlaid GIS vibration heat map and perimeter activity report, forming a closed-loop business exit. The end-to-end success rate of the output is then calculated. End-to-end delay With reporting enable instruction and 4-byte signature The unified mapping is a deterministic link that integrates confidence level, alarm level, and visualization output, so that edge-cloud collaboration can both comply with energy and access constraints and meet real-time early warning and archiving requirements.

[0099] Under conditions of approximately 1.5m burial depth, 60–85m short-range magnetic link, and LoRa / 4G remote backhaul, the data from the on-site star array exhibits characteristics of small packets, multiple points, and sparse temporal sequence. Triggering data using only a single-point probability threshold is highly sensitive to link fluctuations and TDOA errors. Therefore, it is necessary to first complete multi-slave pile aggregation and TDOA time difference verification at the main pile side, and then inject the edge-end 1D-CNN recognition probability and link quality into a unified confidence domain. Subsequently, the cloud uses RAG+MCP+LLM to re-determine, adapt to the environment, and classify and categorize cross-temporal events. Finally, at the B / S end, a regularized threshold triggers an audible and visual alarm for ≥10s, generating direction vectors and heat maps on the GIS, and automatically outputting a perimeter activity report. This transforms physical uncertainty into statistically controllable alarm actions and maintains strict alignment with the upstream energy-access window.

[0100] The main pile integrates the 4-byte signatures of 4–8 slave piles within a single cycle. The consistency of the TDOA geometric time difference was checked based on the soil sound velocity (approximately 200 m / s), resulting in the normalized TDOA mismatch. Edge-end 1D-CNN output behavior recognition probability And it will be integrated along with link quality. To simultaneously consider energy, access, latency, and geometric consistency, a fusion confidence level is defined:

[0101] In the formula, the fusion confidence level Comprehensive metrics used to drive tiered alarms. Report enable instruction Energy-time-slot gating When the value is 0, reporting is directly suppressed; end-to-end success rate : Defined success probability of submission Edge recognition probability : The confidence of the main pile 1D-CNN in the target behavior (the probability corresponding to an accuracy > 98.2%). End-to-end delay Total time delay defined, in seconds (s). Used to suppress delayed rewards; TDOA normalization mismatch The normalized average absolute deviation of the measured time of arrival is calculated by estimating the time difference based on the sound velocity in the soil and the geometric path. Used to penalize inconsistencies in positioning; latency penalty coefficient Delay sensitivity coefficient Geometric penalty coefficient TDOA sensitivity coefficient .

[0102] Energy gating, link quality, model confidence, latency, and geometric consistency are converged into a single confidence level, and exponential suppression is used to avoid the bias of traditional linear weighting. Then, alarm levels are generated using piecewise mapping and bound to the B / S-side actuator.

[0103] In the formula, the alarm level The classification results are as follows: 2 indicates a strong alarm (audio-visual + APP + SMS), 1 indicates a warning (visual board prompts and enhanced heat map), and 0 indicates observation; the threshold for a strong alarm is... The threshold for triggering the audio-visual interaction for 10 seconds. Warning threshold Thresholds for triggering dashboards and GIS enhancements .

[0104] Dual thresholds are used to suppress jitter and false triggers, and the system is aligned with an audio-visual triggering mechanism of ≥10s to ensure verifiable actions. Finally, the cloud uses RAG+MCP+LLM to perform spatiotemporal consistency verification on the propagation path of the same event in adjacent master piles and adjacent time slots, and then merges the confidence scores. Alarm Level Mapped to GIS heatmaps and direction vectors; simultaneously written to a time-series library and automatically compiled perimeter activity reports. Because The reporting enable instruction is already explicitly included. End-to-end success rate End-to-end delay Therefore, it can maintain stable graded action during energy-access fluctuations; when When the alert level rises, the system automatically lowers the alert level or switches to early warning observation to reduce false alarms. The above process is seamlessly integrated with the platform's functions, which include 1 master and 8 slave nodes, LoRa networking, 4G backhaul, GIS dashboards, and report output.

[0105] In one embodiment of the present invention, a piezoelectric cantilever vibration sensing and supercapacitor self-powered closed-loop energy system is provided, comprising: The parameter configuration module establishes a star array consisting of master and slave piles, and configures the TDMA time slots and uplink message length. The energy harvesting and power supply link from the pile is to collect vibration signals from the pile using a piezoelectric cantilever. After being rectified by the piezoelectric rectifier energy harvesting module, the signals are used to charge the supercapacitor and obtain the voltage state across the supercapacitor. When the voltage state reaches the preset upper threshold, the boost module supplies power to the processing circuit and transmitting circuit of the pile, and the processing circuit generates a four-byte feature code. The cross-layer collaborative module sends a four-byte feature code from the pile in the magnetic induction link according to the TDMA time slot. The main pile receives and aggregates the four-byte feature codes sent by multiple slave piles, completes the positioning and fusion based on the time difference of arrival, and transmits it back to the platform via LoRa and 4G. The platform completes the storage and output based on the four-byte feature code and the positioning result.

[0106] When in use, it can be deployed independently or connected to any upper-level monitoring system, with the mechanical interface, power interface and communication interface as the boundaries.

[0107] In the above embodiment, vibration signals are collected from the pile using a piezoelectric cantilever, rectified by a piezoelectric rectifier energy harvesting module, and then used to charge the supercapacitor. Specifically: The energy harvesting and power supply link from the pile is formed by sequentially connecting a polyvinylidene fluoride-trifluoroethylene cantilever, an integrated rectifier energy harvesting chip, a supercapacitor, and a boost chip. The polyvinylidene fluoride-trifluoroethylene cantilever converts low-frequency soil vibration into accumulable DC energy, and completes the continuous energy accumulation and steady-state transition required in the battery-free scenario within the integrated rectifier energy harvesting chip, providing the energy baseline and timing baseline for subsequent supercapacitor energy storage and boost chip voltage boosting.

[0108] In the above embodiments, when the voltage reaches the preset upper threshold, the boost module supplies power to the processing circuit and transmitting circuit of the slave pile. Specifically, the voltage control of the supercapacitor adopts a dual threshold hysteresis strategy with upper and lower thresholds. When the voltage is not lower than the upper threshold, the boost function is activated and the system enters the reporting preparation stage. When the voltage is not higher than the lower threshold, the boost and reporting functions are turned off, and the power-on duration must cover the total processing and transmission time.

[0109] In the above embodiments, the four-byte feature code consists of a category index field, a frequency band summary field, an energy indicator field, and a check field in a fixed order; the master pile sends the bit width and order through the protocol configuration, and the slave pile generates and caches the four-byte feature code according to the configuration.

[0110] In the above embodiment, the slave pile sends a four-byte feature code in the magnetic induction link according to the TDMA time slot. The master pile receives and aggregates the four-byte feature codes sent by multiple slave piles. Specifically, it performs uplink transmission or one-hop relay according to the configured time slot and addressing overhead, so as to realize the simultaneous completion of vibration sensing and data transmission under the condition of no external power supply. Among them, the magnetic induction uplink adopts a near-field link coupled with ferrite rods, the access adopts time division multiple access and sets preamble, guard interval and addressing overhead, the relay adopts a mesh topology and prioritizes the least number of hops, and if there is an equivalent path, the path with the higher end-to-end success rate is selected.

[0111] In the above embodiments, the star array composed of main piles and slave piles is arranged in a staggered scattering pattern with one main pile and eight slave piles. The slave piles are buried at a preset depth and maintain a set spacing with the main piles. The main piles are connected by a long-distance low-power wireless network, and the main piles and the platform are connected by mobile communication.

[0112] In the above embodiments, the arrival times of four to eight slave piles are aggregated in a single cycle and the arrival time difference is located and verified using a soil sound velocity calibration model. On the edge side, a one-dimensional convolutional small model is used to output the behavior confidence. The platform fuses the events of multiple master piles and multiple time slots according to preset rules.

[0113] In the above embodiments, the hardware composition and interface of this system are as follows: An integrated housing is used, with a concave top surface at the front end for enhanced low-frequency coupling via an acoustic metamaterial waveguide. Internally, a PVDF-TrFE cantilever, an energy harvesting and storage cavity, and a near-field communication cavity are arranged sequentially, with a high-permeability shielding layer on the inner wall. The circuitry, from front to back, consists of: piezoelectric terminal - rectification and energy harvesting front end - supercapacitor - boost output - microcontroller - near-field transmitter / relay unit. Three types of interfaces are publicly disclosed: Mechanical interface: Cylindrical housing and three-section screw-on tail rod, suitable for hammering into the soil or surface fixing; Power interface: Only the energy storage bus voltage reading pin (read-only) and boost output test pin (read-only) are exposed to the outside; Communication interface: Near-field link air interface protocol, supports fixed-length four-byte signature code, including three configurable items: time slot, protection interval and addressing overhead.

[0114] In the above embodiments, the workflow and state machine of this system adopt a five-state cycle of charging-preparation-sampling and coding-transmission-sleep, specifically as follows: Charging state: The piezoelectric terminal is rectified and charged to the supercapacitor; Ready state: When the energy storage bus voltage reaches the upper threshold, the boost output is turned on and the timing begins; Sampling and coding: The microcontroller reads the window signal within the energy budget and generates a four-byte feature code according to the preset feature operator and quantization mapping; Transmitting state: Complete near-field transmission or one-hop relay within the configured time slot; Dormant state: When the voltage of the energy storage bus drops to the lower threshold or the timer expires, the boost is turned off and the charging state is returned.

[0115] The upper threshold, lower threshold, window duration, and time slot length are uniformly distributed by the configuration table to ensure consistency between different batches of modules.

[0116] In the above embodiments, the feature and encoding interface of this system (publicly disclosed) is as follows: the feature operator is used to compress the window signal into a four-element feature, and the quantization mapping packages it into a four-byte payload. The field order is category index / band digest 1 / band digest 2 / energy indicator / CRC, the bit width is fixed, and the band boundary and quantization scale can be configured remotely. The main system or any host system can parse it using the same table.

[0117] Optional features include: magnetic induction one-hop relay to enhance reachability; a tapered resonant plate at the front end of the housing; voltage divider reading of the energy storage bus voltage for remote health reporting; replacement of field width without changing the four-byte length; and adjustment of bandpass preset and sampling window under different media environments.

[0118] In the above embodiments, this system can be connected to an existing monitoring system as a pluggable submodule. When interfacing with the main pile: the main pile is only responsible for near-field reception, feature aggregation, and necessary positioning and identification; when interfacing with bridge / track / perimeter systems: the four-byte feature code serves as the smallest message unit of the upper-layer link and can be encapsulated and transmitted back by any gateway; when interfacing with the platform / GIS: the platform does not need to understand the internal energy flow of this module, but only parses the four-byte code and performs visualization and alarm functions.

[0119] The system operates in a cycle of "charging - preparation - sampling and coding - near-field transmission - hibernation": External vibration disturbances first generate strain on the piezoelectric cantilever and form an instantaneous current between the electrodes, which is then rectified and fed into the supercapacitor. When the energy storage voltage reaches the upper threshold, the boost output is activated. Within the energy budget, the microcontroller performs windowing processing on the high-impedance sampling signal of the piezoelectric terminal, generates a four-byte feature code based on the preset feature operator and quantization mapping, and transmits it through the near-field link within the configured time slot. When the energy storage voltage drops to the lower threshold or the window expires, the boost output is turned off and the system returns to the charging state.

[0120] In the above embodiments, the system of the present invention also includes a self-powered near-field communication module for piezoelectric vibration sensing and supercapacitor energy storage. The self-powered near-field communication module uses a piezoelectric cantilever as the sole front-end sensing and transducer element. The same vibration disturbance induces mechanical strain on the cantilever and simultaneously generates polarization charge and instantaneous current. This current is rectified and captured by the supercapacitor to form usable DC energy. Simultaneously, the high-impedance measurement branch reads the piezoelectric terminal voltage / current without disturbance as the vibration signal input. The edge processing unit generates a fixed-length four-byte feature code, which is then transmitted uplinked by the near-field communication unit within a time slot. The boost and stabilization units are controlled by the energy storage voltage threshold to ensure that, under conditions without external power supply, the vibration → self-generation → energy storage → power-on → code generation → uplink sequence closes in a unified time sequence as a reusable submodule.

[0121] The system provided in this embodiment is used to execute the above-described method embodiments. For specific processes and details, please refer to the above embodiments, which will not be repeated here.

[0122] In one embodiment of the present invention, a computing device is provided. This computing device can be a terminal and may include a processor, a communication interface, memory, a display screen, and an input device. The processor, communication interface, and memory communicate with each other via a communication bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and computer programs. When the computer programs are executed by the processor, they implement the methods described in the above embodiments. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The communication interface is used for wired or wireless communication with external terminals. Wireless communication can be achieved through Wi-Fi, a management network, NFC (Near Field Communication), or other technologies. The display screen can be a liquid crystal display (LCD) or an e-ink display. The input device can be a touch layer covering the display screen, or buttons, a trackball, or a touchpad mounted on the casing of the computing device, or an external keyboard, touchpad, or mouse. The processor can call logical instructions stored in the memory.

[0123] Furthermore, the logical instructions in the aforementioned memory can be implemented as software functional units and sold or used as independent products, and can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0124] In one embodiment of the present invention, a computer program product is provided, the computer program product including a computer program stored on a non-transitory computer-readable storage medium, the computer program including program instructions, and when the program instructions are executed by a computer, the computer is able to perform the methods provided in the above-described method embodiments.

[0125] In one embodiment of the present invention, a non-transitory computer-readable storage medium is provided, which stores server instructions that cause a computer to perform the methods provided in the above embodiments.

[0126] The computer-readable storage medium provided in the above embodiments has a similar implementation principle and technical effect to the above method embodiments, and will not be described again here.

[0127] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0128] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0129] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0130] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A closed-loop operation method for piezoelectric cantilever vibration sensing and supercapacitor self-powered energy, characterized in that, include: Establish a star array consisting of master and slave nodes, and configure TDMA time slots and uplink message length; Vibration signals are collected from the pile using a piezoelectric cantilever. After being rectified by the piezoelectric rectifier energy harvesting module, the signals are used to charge the supercapacitor, thus obtaining the voltage state across the supercapacitor. When the voltage state reaches a preset upper threshold, the boost module supplies power to the processing and transmitting circuits of the pile, and the processing circuit generates a four-byte feature code. The slave pile sends a four-byte feature code in the magnetic induction link according to the TDMA time slot. The master pile receives and aggregates the four-byte feature codes sent by multiple slave piles, completes the positioning and fusion according to the time difference of arrival, and transmits it back to the platform via LoRa and 4G. The platform completes the storage and output according to the four-byte feature code and the positioning result.

2. The piezoelectric cantilever vibration sensing and supercapacitor self-powered closed-loop operation method as described in claim 1, characterized in that, Vibration signals are collected from the pile using a piezoelectric cantilever, rectified by a piezoelectric rectifier energy harvesting module, and then used to charge a supercapacitor. Specifically: The energy harvesting and power supply link from the pile is formed by sequentially connecting a polyvinylidene fluoride-trifluoroethylene cantilever, an integrated rectifier energy harvesting chip, a supercapacitor, and a boost chip. The polyvinylidene fluoride-trifluoroethylene cantilever converts low-frequency soil vibration into accumulable DC energy, and completes the continuous energy accumulation and steady-state transition required in the battery-free scenario within the integrated rectifier energy harvesting chip, providing the energy baseline and timing baseline for subsequent supercapacitor energy storage and boost chip voltage boosting.

3. The piezoelectric cantilever vibration sensing and supercapacitor self-powered closed-loop operation method as described in claim 2, characterized in that, When the voltage reaches the preset upper threshold, the boost module supplies power to the processing circuit and transmitting circuit of the slave pile. Specifically, the voltage control of the supercapacitor adopts a dual threshold hysteresis strategy with upper and lower thresholds. When the voltage is not lower than the upper threshold, the boost function is activated and the system enters the reporting preparation stage. When the voltage is not higher than the lower threshold, the boost and reporting functions are turned off, and the power-on duration must cover the total processing and transmission time.

4. The piezoelectric cantilever vibration sensing and supercapacitor self-powered closed-loop operation method as described in claim 1, characterized in that, The four-byte signature consists of a category index field, a frequency band summary field, an energy indicator field, and a check field in a fixed order; the master stake sends the bit width and order through the protocol configuration, and the slave stake generates and caches the four-byte signature according to the configuration.

5. The piezoelectric cantilever vibration sensing and supercapacitor self-powered closed-loop operation method as described in claim 1, characterized in that, The slave pile sends a four-byte feature code in the magnetic induction link according to the TDMA time slot. The master pile receives and aggregates the four-byte feature codes sent by multiple slave piles. Specifically, it performs uplink transmission or one-hop relay according to the configured time slot and addressing overhead, so as to realize the simultaneous completion of vibration sensing and data transmission under the condition of no external power supply. Among them, the magnetic induction uplink adopts a near-field link coupled with ferrite rods, the access adopts time division multiple access and sets preamble, guard interval and addressing overhead, the relay adopts a mesh topology and prioritizes the least number of hops, and if there is an equivalent path, the path with the higher end-to-end success rate is selected.

6. The piezoelectric cantilever vibration sensing and supercapacitor self-powered closed-loop operation method as described in claim 1, characterized in that, The star array consisting of main piles and slave piles is arranged in a staggered scattering pattern with one main pile and eight slave piles. The slave piles are buried at a preset depth and maintain a set spacing from the main piles. The main piles are connected by a long-distance low-power wireless network, and the main piles and the platform are connected by mobile communication.

7. The piezoelectric cantilever vibration sensing and supercapacitor self-powered closed-loop operation method as described in claim 6, characterized in that, Within a single cycle, the arrival times of four to eight slave piles are aggregated for the main pile, and the arrival time difference is used for location verification using a soil sound velocity calibration model. On the edge side, a one-dimensional convolutional small model is used to output the behavioral confidence. The platform fuses events from multiple main piles and multiple time slots according to preset rules.

8. A piezoelectric cantilever vibration sensing and supercapacitor self-powered closed-loop energy system, characterized in that, include: The parameter configuration module establishes a star array consisting of master and slave piles, and configures the TDMA time slots and uplink message length. The energy harvesting and power supply link from the pile is to collect vibration signals from the pile using a piezoelectric cantilever. After being rectified by the piezoelectric rectifier energy harvesting module, the signals are used to charge the supercapacitor and obtain the voltage state across the supercapacitor. When the voltage state reaches the preset upper threshold, the boost module supplies power to the processing circuit and transmitting circuit of the pile, and the processing circuit generates a four-byte feature code. The cross-layer collaborative module sends a four-byte feature code from the pile in the magnetic induction link according to the TDMA time slot. The main pile receives and aggregates the four-byte feature codes sent by multiple slave piles, completes the positioning and fusion based on the time difference of arrival, and transmits it back to the platform via LoRa and 4G. The platform completes the storage and output based on the four-byte feature code and the positioning result.

9. A computer-readable storage medium for storing one or more programs, characterized in that, The one or more programs include instructions that, when executed by a computing device, cause the computing device to perform any of the methods described in claims 1 to 7.

10. A computing device, characterized in that, include: One or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including instructions for performing any of the methods described in claims 1 to 7.

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