A multi-channel time-series control and early warning method for debris flow

Abstract

The present invention provides a multi-channel time-sequence control early warning method for debris flow. First, three debris flow ground sound early warning instruments are used to form a monitoring array, which is configured as master-slave and networked; the master-slave devices are configured to collect parameters, the collection period is 2t, the collection duration of each device is t, and the start time of data collection of the three devices in each period is separated by t / 2; data collection and data analysis and early warning are carried out according to the collection time sequence; if any device is determined to be in the debris flow early warning state, the master device records the debris flow early warning event; if the master device records the debris flow early warning event three times in a row, a debris flow early warning notice is sent to the monitoring center. This method conducts real-time early warning through the time-sequence control of the monitoring array, with comprehensive data collection, low power consumption, timely early warning, high accuracy, and can directly perform multi-device linkage decision-making and early warning at the front end, having the advantages of convenient installation and debugging.

Description

Technical Field

[0001] The present invention belongs to the technical field of geological disaster monitoring, and particularly relates to a multi-channel time-sequence control early warning method for debris flow. Background Art

[0002] It is known from public research that the ground sound frequencies of debris flows in different forms are different, basically ranging from 5 Hz to 300 Hz. Considering the technical limitations of the natural frequency of the ground sound sensor itself, it is difficult for the device to collect ultra-low frequency signals below 1 Hz. In the actual monitoring process, it is found that the low-frequency ground sound signal attenuates slowly and has a long propagation distance, while the high-frequency signal can only be monitored at the source of the debris flow gully.

[0003] The existing ground sound sensors are basically of a three-component architecture. If the signal acquisition range is between 0.2 Hz and 50 Hz, the sampling frequency of the ground sound early warning instrument should be set at least at 250 Hz to collect relatively accurate ground sound signals. According to 2 bytes per sampling point, the ground sound early warning instrument uploads about 1500 bytes per second. If the 4G real-time transmission method is adopted, the data volume and power consumption are too large for field data transmission equipment. In order to reduce power consumption, the ground sound sensor often adopts an intermittent acquisition method, but this method will lead to incomplete data acquisition and reduce the timeliness and accuracy of early warning. In addition, due to the fast attenuation of the ground sound signal, it is difficult to comprehensively capture the signal with a single ground sound sensor, which will also reduce the data accuracy.

[0004] In summary, in the prior art, there are often technical problems such as incomplete acquisition of raw data, high power consumption, untimely early warning, and low early warning accuracy rate in the debris flow ground sound early warning instrument. Summary of the Invention

[0005] The present invention provides a multi-channel time-sequence control early warning method for debris flow. By arranging three sets of debris flow ground sound early warning instruments on the flow path of the debris flow to form a monitoring array, and through array time-sequence control, the monitoring data of multiple sets of devices form a continuous data set, and real-time early warning is carried out through data analysis.

[0006] The technical solution adopted by the present invention to achieve the above object is as follows:

[0007] A multi-channel time-sequence control early warning method for debris flow, comprising the following steps

[0008] Use three debris flow ground sound early warning instruments to form a monitoring array, and configure one as the master device and the others as slave devices;

[0009] The master and slave devices are powered on, self-tested, time-synchronized, and networked;

[0010] Configure the master and slave devices to collect parameters. The data collection period of the master and slave devices is 2t, the data collection duration of each device is t, and the start time of data collection for the three devices in each cycle is separated by t / 2.

[0011] In each cycle, the master and slave devices collect data according to the collection time sequence, and enter data analysis and early warning after collection.

[0012] If any one of the devices is in the debris flow early warning state after data analysis and early warning judgment, the master device records a debris flow early warning event.

[0013] The master and slave devices collect data and perform data analysis in cycles.

[0014] If the master device records debris flow early warning events three times in a row, it issues a debris flow early warning notice to the monitoring center.

[0015] Furthermore, the data analysis and early warning include the following processing steps

[0016] Divide the data of t duration collected by the ground sound sensor into two data packets of t / 2 duration.

[0017] Calculate the time-domain energy in three directions of each data packet. If any one of the six time-domain energies is greater than the set energy threshold, proceed to the next step; otherwise, the device enters the standby mode.

[0018] Calculate the amplitude spectrum and energy spectrum of each data packet, select the energy value in the frequency range of 0.2 - 50Hz of the ground sound signal from the energy spectrum, and calculate the energy proportion factor of the energy value in the frequency range of 0.2 - 50Hz of the ground sound signal in three directions of the ground sound sensor.

[0019] If more than two of the energy proportion factors in the three directions exceed the energy proportion factor threshold, report a debris flow early warning state, and the device exits the data analysis and early warning mode; otherwise, the device directly exits the data analysis and early warning mode.

[0020] Furthermore, the calculation method of the energy proportion factor in three directions is as follows

[0021] K1 = (Wx1 + Wx2) / (Ex1 + Ex2)

[0022] K2 = (Wy1 + Wy2) / (Ey1 + Ey2)

[0023] K3 = (Wz1 + Wz2) / (Ez1 + Ez2)

[0024] Among them, Wx1, Wy1, and Wz1 are respectively the sum of the energy values of the ground sound signals in the three directions corresponding to the first t / 2 time period within the frequency range of 0.2 to 50 Hz; Wx2, Wy2, and Wz2 are respectively the sum of the energy values of the ground sound signals in the three directions corresponding to the second t / 2 time period within the frequency range of 0.2 to 50 Hz; Ex1, Ey1, and Ez1 are respectively the time-domain energies in the three directions corresponding to the first t / 2 time period; Ex2, Ey2, and Ez2 are respectively the time-domain energies in the three directions corresponding to the second t / 2 time period.

[0025] Further, the value range of t is 10S to 30S; the energy threshold is set to 2.5 to 5 times the background threshold.

[0026] Further, the three debris flow ground sound warning devices are arranged in a triangular array or a linear array, and the main device is placed at the center position of the array.

[0027] Further, the debris flow ground sound warning device includes a ground sound sensor and an integrated warning transmission unit, and the integrated warning transmission unit is connected to the ground sound sensor through a cable;

[0028] The integrated warning transmission unit includes an acquisition transmission warning sub-unit, a power supply sub-unit, and a support structure member. The acquisition transmission warning sub-unit and the power supply sub-unit are installed on the support structure member. The acquisition transmission warning sub-unit includes a microprocessor module, a storage module, a 4G communication module, a Beidou satellite communication module, a LoRA communication module, and a Bluetooth module, which are used to complete the signal acquisition, storage, data sending, and warning functions of the on-site ground sound sensor.

[0029] Further, the ground sound sensor is a three-component sensor with a natural frequency lower than 0.5 Hz; the interface between the ground sound sensor and the integrated warning transmission unit is a digital interface.

[0030] Further, the ground sound sensor is buried within the range of 0.5 meters to 1 meter from the ground.

[0031] Advantages of the present invention compared with the prior art:

[0032] A debris flow multi-channel timing control warning method provided by the present invention forms a monitoring array by arranging three sets of debris flow ground sound warning devices on the flowing path of the debris flow, and through array timing control, the monitoring data of multiple devices form a continuous data set, and real-time warning is carried out through data analysis, solving the problems of incomplete acquisition of original data, high power consumption, untimely warning, low warning accuracy, and insufficient real-time performance of platform comprehensive warning of existing conventional monitoring devices. This method can directly perform linkage decision warning on multiple front-end devices, and has the advantages of convenient installation, easy debugging, and high warning real-time performance. Description of the Drawings

[0033] The accompanying drawings included are used to provide a further understanding of the embodiments of the present invention, which form a part of the specification, illustrate the embodiments of the present invention, and, together with the written description, explain the principles of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can obtain other drawings based on these drawings without creative efforts.

[0034] Figure 1 Schematic diagram of the composition of the debris flow ground sound early warning instrument provided for specific embodiments of the present invention;

[0035] Figure 2 Array acquisition timing diagram of the debris flow ground sound early warning instrument provided for specific embodiments of the present invention. Specific embodiments

[0036] The following will detail the specific embodiments of the present invention. In the following description, for purposes of explanation rather than limitation, specific details are set forth to facilitate a comprehensive understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may also be practiced in other embodiments without these specific details.

[0037] It should be noted here that in order to avoid obscuring the present invention with unnecessary details, only the device structures and / or processing steps closely related to the solution of the present invention are shown in the drawings, while other details less related to the present invention are omitted.

[0038] A debris flow multi-channel timing control early warning method provided by the present invention includes the following steps

[0039] Use three debris flow ground sound early warning instruments to form a monitoring array, configure one as the master device and the others as slave devices;

[0040] Power on, self-check, time synchronization, and network formation for the master and slave devices;

[0041] Configure the acquisition parameters of the master and slave devices. The data acquisition period of the master and slave devices is 2t, the acquisition duration of each device is t, and the start time of data acquisition for the three devices in each cycle is separated by t / 2;

[0042] In each cycle, the master and slave devices perform data acquisition according to the acquisition timing, and enter the data analysis and early warning mode after acquisition;

[0043] If any device is determined to be in the debris flow early warning state after passing through the data analysis and early warning mode, the master device records a debris flow early warning event;

[0044] The master and slave devices perform cyclic acquisition and data analysis according to the cycle;

[0045] If the master device records debris flow warning events three times in a row, a debris flow warning notice will be issued to the monitoring center.

[0046] The warning method of the present invention forms a monitoring array by arranging three sets of debris flow ground sound warning instruments on the flow path of the debris flow, and through array timing control, the monitoring data of multiple devices form a continuous data set. Real-time warning is carried out through data analysis. The data collection is comprehensive, the power consumption is small, the warning is timely, and the warning accuracy is high. This method can directly make joint decisions and warnings for multiple devices at the front end, and has the advantages of convenient installation and debugging.

[0047] A debris flow multi-channel timing control warning method provided by the present invention has a debris flow ground sound warning instrument as the main carrier. The debris flow ground sound warning instrument mainly includes a ground sound sensor and an integrated warning transmission unit.

[0048] The ground sound sensor is an ultra-low frequency (natural frequency lower than 0.5 Hz) and high-sensitivity three-component sensor, which can be placed at a long distance to sense the vibration signal generated when a debris flow occurs. The digital interface between the ground sound sensor and the integrated warning transmission unit is more conducive to the long-distance distortion-free transmission of weak signals compared with the analog interface. Because the ground sound sensor is an ultra-low frequency sensor, it can be placed 0.5 kilometers away from the debris flow source. After the debris flow occurs, there is enough time for safe evacuation. The ground sound sensor is placed near the flow path of the debris flow. In order to reduce wind noise and mechanical interference on the ground, preferably, the ground sound sensor is buried 0.5 to 1 meter below the ground surface.

[0049] The integrated warning transmission unit includes an acquisition transmission warning sub-unit, a power supply sub-unit and a support structure member. The acquisition transmission warning sub-unit and the power supply sub-unit are installed on the support structure member. The integrated warning transmission unit is placed near the ground sound sensor and is connected to the ground sound sensor by a cable. The acquisition transmission warning sub-unit includes a microprocessor module, a storage module, a 4G communication module, a Beidou satellite communication module, a LoRA communication module, and a Bluetooth module, which mainly complete the signal acquisition, storage, data sending and warning functions of the on-site ground sound sensor. Among them, the microprocessor module is used as the overall control and coordination unit to schedule all devices to complete the set tasks; the storage module is used to store device parameter information, acquired ground sound data, etc.; 4G communication is the main communication method for emergencies. When the on-site 4G signal is poor, it will automatically switch to the Beidou communication method. The Beidou satellite communication module provides both timing and communication functions; LoRA communication is used for on-site networked joint warning; the Bluetooth module is used for on-site wireless debugging. The power supply sub-unit provides power input for each module in the debris flow ground sound warning instrument. In an array unit, one set can be selected as the master device, and the others as slave devices.

[0050] A multi-channel time-sequence control early warning method for debris flow provided by the present invention mainly uses three debris flow ground sound early warning instruments to form a monitoring array, which can be arranged in a triangular array or a linear array. The main device in the monitoring array is placed at the center of the array, and the distance between the main device and the slave devices is preferably about 50 meters. The devices in the monitoring array use LoRa for data transmission. Through the layout of the monitoring array, the problems of rapid attenuation of ground sound signals and incomplete signal capture by single-point ground sound sensors are effectively solved. Multiple points on the flow path of the debris flow are monitored, and the signals at multiple points are complementary to ensure the continuity of the signals.

[0051] A multi-channel time-sequence control early warning method for debris flow provided by the present invention uses three debris flow ground sound early warning instruments to form a monitoring array. Denote the three devices as A, B, and C respectively, where A is the main device and B and C are both slave devices. To ensure the continuity of on-site data collection and the optimization of device power consumption, the time sequences of A, B, and C adopt a method of overlapping part of the collection time periods (in each cycle, A, B, and C respectively collect data in three time periods, the three time periods cover the entire cycle, and there is partial data overlap between the three time periods). After the three devices collect and analyze the data, they are in a low-power standby mode. The multi-channel time-sequence control early warning method for debris flow includes the following steps:

[0052] (1) The main device and the slave devices are powered on to complete their respective initializations;

[0053] (2) The main device and the slave devices complete their respective device status self-checks;

[0054] (3) The main device and the slave devices complete time synchronization;

[0055] (4) The main device sends a handshake signal in a broadcast manner;

[0056] (5) The slave devices send response signals to the main device;

[0057] (6) The main device sends on-site parameters to slave device B and slave device C. The on-site parameters include the start collection time tA0, the sampling period 2t, and the collection sequences of slave device B and slave device C;

[0058] (7) Slave devices B and C store the on-site parameters and wait for collection according to the set collection sequences. For example, if slave device B is sequence 1, the start collection time of B is tA0 + t / 2; if slave device C is sequence 2, the collection time of C is tA0 + t;

[0059] (8) If the start time tA0 arrives, the main device A enters the collection mode and starts to collect data of the three components (X, Y, Z) of the ground sound sensor for a duration of t. After collection, it enters the data analysis and early warning mode;

[0060] If the startup time tA0 has not arrived or the data collection and transmission for this cycle have ended, the master device A is in the standby mode; the master device A repeats step 8 at intervals of cycle 2t;

[0061] (9) If the startup time tA0 + t / 2 arrives, the slave device B enters the collection mode, starts to collect data for a duration of t, and enters the data analysis and early warning mode after collection; if the startup time tA0 + t / 2 has not arrived or the data collection and transmission for this cycle have ended, the slave device B is in the standby mode; the slave device B repeats step 9 at intervals of cycle 2t;

[0062] (10) If the startup time tA0 + t arrives, the slave device C enters the collection mode, starts to collect data for a duration of t, and enters the data analysis and early warning mode after collection; if the startup time tA0 + t has not arrived or the data collection and transmission for this cycle have ended, the slave device C is in the standby mode; the slave device C repeats step 10 at intervals of cycle 2t;

[0063] (11) If any one of devices A, B, and C is determined to be in the debris flow early warning state after the data analysis and early warning mode, the master device A records a debris flow early warning event;

[0064] (12) Repeat steps 8 to 11;

[0065] (13) If the master device records three consecutive early warning events, the master device issues a debris flow early warning notice to the monitoring center.

[0066] A debris flow multi-channel timing control early warning method provided by the present invention, in which both the master device and the slave device have three working modes: 1) data collection mode, 2) transmission mode, 3) standby mode; the data collection mode refers to collecting data of three components of the ground acoustic sensor at a set sampling rate; the transmission mode of the master device includes LoRA network transmission and uploading of debris flow early warning notices, etc., and the transmission mode of the slave device is mainly to send it to the master device through LoRA when it is determined to be a debris flow early warning event; in the standby mode, except for the timer interrupt being turned on, all other power supplies of the device are in the off mode.

[0067] A debris flow multi-channel timing control early warning method provided by the present invention, wherein the data analysis and early warning mode of any three-component ground acoustic sensor includes the following processing steps:

[0068] (1) Divide the data of duration t collected by the three-component ground acoustic sensor into 2 data packets of duration t / 2; where t is generally 10S - 30S; dividing the duration t into 2 durations of t / 2 can perform a more accurate analysis of the frequency components in the time series.

[0069] (2) Calculate the time-domain energy of the data packets in two time periods of t / 2 respectively. The time-domain energy corresponding to the first t / 2 time period in three directions is Ex1, Ey1, and Ez1, and the time-domain energy corresponding to the second t / 2 time period in three directions is Ex2, Ey2, and Ez2. If the time-domain energy in one direction in the two t / 2 time periods is greater than the set energy threshold E 阈值 / 2, then proceed to step 3; otherwise, the device enters the standby mode; where the energy threshold E 阈值 is generally set to 5 to 10 times the background threshold;

[0070] (3) Perform FFT transformation on the data packets in two time periods of t / 2 respectively to obtain their amplitude spectra, and then calculate the energy spectra of the data in the two t / 2 time periods;

[0071] (4) Select the energy values within the frequency range of the subsurface acoustic signal (0.2 - 50) Hz from the energy spectra of each data packet. Calculate the sum of all energy values in three directions corresponding to the first t / 2 time period as Wx1, Wy1, and Wz1, calculate the sum of all energy values in three directions corresponding to the second t / 2 time period as Wx2, Wy2, and Wz2, and calculate the energy proportion factors of the device in three directions as K1 = (Wx1 + Wx2) / (Ex1 + Ex2), K2 = (Wy1 + Wy2) / (Ey1 + Ey2), K3 = (Wz1 + Wz2) / (Ez1 + Ez2);

[0072] (5) Calculate the number of K1, K2, and K3 that are greater than the energy proportion factor threshold K. If the number is greater than or equal to 2, report a debris flow warning status once, and at the same time, the device exits the data analysis and warning mode; otherwise, the device directly exits the data analysis and warning mode.

[0073] A debris flow multi-channel time-sequence control warning method provided by the present invention adopts a multi-channel acquisition method with partially overlapping acquisition time periods to reduce power consumption and meet the user's requirements for collecting original data and continuous acquisition of on-site data samples.

[0074] The features described and / or illustrated for one embodiment above can be used in the same or similar manner in one or more other embodiments, and / or combined with the features in other embodiments or replace the features in other embodiments.

[0075] It should be emphasized that the term "including / comprising" when used herein refers to the presence of features, whole things, steps or components, but does not exclude the presence or addition of one or more other features, whole things, steps, components or their combinations.

[0076] Many features and advantages of these embodiments will be apparent from this detailed description, and thus the appended claims are intended to cover all such features and advantages of these embodiments that fall within their true spirit and scope. Moreover, since many modifications and variations will readily occur to those skilled in the art, the embodiments of the invention are not to be limited to the exact construction and operation shown and described, but may cover all suitable modifications and equivalents that fall within their scope.

[0077] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, various changes and modifications can be made to the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

[0078] The parts not described in detail in the present invention are well-known technologies to those skilled in the art.

Claims

1. A multi-channel time-series control and early warning method for debris flow, characterized in that, It includes the following steps: Three debris flow ground sound warning devices form a monitoring array, with one configured as the master device and the others as slave devices; The master and slave devices are powered on, self-checked, time-synchronized, and networked; Configure the acquisition parameters of the master and slave devices. The data acquisition period of the master and slave devices is 2t, the acquisition duration of each device is t, and the start acquisition times of the three devices in each cycle are separated by t / 2; In each cycle, the master and slave devices perform data acquisition according to the acquisition timing sequence, and enter data analysis and warning after acquisition; If any one of the devices is determined to be in the debris flow warning state after data analysis and warning, the master device records a debris flow warning event; The master and slave devices perform cyclic acquisition and data analysis according to the cycle; If the master device records debris flow warning events three times in a row, it issues a debris flow warning notice to the monitoring center; The data analysis and warning includes the following processing steps: Divide the data of t duration collected by the ground sound sensor into two data packets of t / 2 duration; Calculate the time-domain energy in three directions of each data packet. If any one of the six time-domain energies is greater than the set energy threshold, proceed to the next step, otherwise the device enters the standby mode; Calculate the amplitude spectrum and energy spectrum of each data packet, select the energy value in the frequency range of 0.2~50Hz of the ground sound signal from the energy spectrum, and calculate the energy ratio factor of the energy value in the frequency range of 0.2~50Hz of the ground sound signal in three directions of the ground sound sensor; If more than two of the energy ratio factors in the three directions exceed the energy ratio factor threshold, report a debris flow warning state once, and the device exits the data analysis and warning mode; otherwise, the device directly exits the data analysis and warning mode.

2. The multi-channel time-series control and early warning method for debris flow according to claim 1, wherein The calculation method of the energy ratio factor in three directions is as follows K1 = (Wx1 + Wx2) / (Ex1 + Ex2) K2 = (Wy1 + Wy2) / (Ey1 + Ey2) K3 = (Wz1 + Wz2) / (Ez1 + Ez2) Where, Wx1, Wy1, and Wz1 are the sums of the energy values in the frequency range of 0.2~50Hz of the ground sound signals in the three corresponding directions of the first t / 2 duration; Wx2, Wy2, and Wz2 are the sums of the energy values in the frequency range of 0.2~50Hz of the ground sound signals in the three corresponding directions of the second t / 2 duration; Ex1, Ey1, and Ez1 are the time-domain energies in the three corresponding directions of the first t / 2 duration; Ex2, Ey2, and Ez2 are the time-domain energies in the three corresponding directions of the second t / 2 duration.

3. The multi-channel time-sequence control and early warning method for debris flow according to claim 1, wherein The value range of t is 10S~30S; the energy threshold is set to 2.5~5 times the background threshold.

4. The multi-channel time-sequence control and early warning method for debris flow according to claim 1, wherein The three debris flow ground sound warning devices are arranged in a triangular array or a linear array, and the master device is placed at the center position of the array.

5. The debris flow multi-channel time-sequence control and early warning method according to claim 1, characterized in that The debris flow ground sound warning device includes a ground sound sensor and an integrated warning transmission unit, and the integrated warning transmission unit is connected to the ground sound sensor through a cable; The integrated early warning transmission unit includes an acquisition and transmission early warning sub-unit, a power supply sub-unit, and a support structure member. The acquisition and transmission early warning sub-unit and the power supply sub-unit are installed on the support structure member. The acquisition and transmission early warning sub-unit includes a microprocessor module, a storage module, a 4G communication module, a Beidou satellite communication module, a LoRA communication module, and a Bluetooth module, which are used to complete the signal acquisition, storage, data transmission, and early warning functions of on-site ground acoustic sensors.

6. The multi-channel time-series control and early warning method for debris flow according to claim 5, characterized in that The ground acoustic sensor is a three-component sensor with a natural frequency lower than 0.5 Hz; the interface between the ground acoustic sensor and the integrated early warning transmission unit is a digital interface.

7. The debris flow multi-channel time-sequence control warning method according to claim 5, characterized in that The ground acoustic sensor is buried within the range of 0.5 to 1 meter from the ground surface.

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