阅读说明：本技术 一种隧道主动源地震波无线采集、终端、系统、方法及介质 (Tunnel active source seismic wave wireless acquisition terminal, system, method and medium ) 是由 庞岩 李尧 张宝利 刘丛林 田连辉 顾佳俊 唐华伟 黑爽 于 2021-08-06 设计创作，主要内容包括：本发明公开一种隧道主动源地震波无线采集方法、系统及终端,涉及隧道工程技术领域,实现过程包括：上位机通信连接无线接入主站,无线接入主站无线连接多台无线采集终端；开机,通过上位机设置采样参数；启动采样,主站进行AD采样,并向终端下发启动采样指令,终端开始进行AD采样；主站读取AD采样结果,在结果超过设定阈值时,主站同时向终端和上位机传送触发完成指令；上位机收到触发完成指令后开始计时,经设定采样时间后,终端完成采样；上位机向接入的终端下发上传数据指令,终端将存储的AD采样数据上传至上位机,上位机对收到的数据进行存储和解析,并显示各无线采集终端、各通道的波形。本方法的采样数据具有精度高、可回溯的特点。(The invention discloses a tunnel active source seismic wave wireless acquisition method, a system and a terminal, which relate to the technical field of tunnel engineering and comprise the following steps: the upper computer is in communication connection with a wireless access master station, and the wireless access master station is in wireless connection with a plurality of wireless acquisition terminals; starting up the computer, and setting sampling parameters through an upper computer; starting sampling, wherein the master station carries out AD sampling and issues a sampling starting instruction to the terminal, and the terminal starts AD sampling; the master station reads the AD sampling result, and when the result exceeds a set threshold value, the master station simultaneously transmits a trigger completion instruction to the terminal and the upper computer; the upper computer starts timing after receiving the trigger completion instruction, and the terminal completes sampling after the sampling time is set; the upper computer issues a data uploading instruction to the accessed terminal, the terminal uploads the stored AD sampling data to the upper computer, and the upper computer stores and analyzes the received data and displays the waveforms of each wireless acquisition terminal and each channel. The method has the characteristics of high precision and traceability of the sampled data.)

1. A tunnel active source seismic wave wireless acquisition terminal is characterized by comprising:

the control module is used for managing the wireless module, the sampling module, the delay eliminating module, the data storage module, the power supply module, the clock module and the CPLD module and reading the sampled data;

the wireless module is used for carrying out wireless communication with the wireless access master station and the upper computer, and comprises a function of receiving a sampling starting instruction or a triggering completion instruction sent by the wireless access master station or receiving a data uploading instruction sent by the upper computer and transmitting data to the upper computer;

the sampling module is used for carrying out AD sampling on the output of the detector after receiving a sampling starting instruction or a triggering completion instruction;

the time delay elimination module comprises a time recording module and a data processing module;

the time recording module is used for recording sampling time Ts and sampling backtracking time Tb, and subtracting the sampling backtracking time Tb from the sampling time Ts, namely Tc is Ts-Tb;

the data processing module comprises a storage area 1 and a storage area 2, and is used for storing the sampling data within the sampling backtracking time Tb after the wireless module receives the sampling starting instruction in the storage area 1 and storing the sampling data within the whole sampling time Ts of the wireless module in the storage area 2.

2. The wireless acquisition terminal for the seismic waves of the tunnel active source of claim 1, wherein:

after the wireless module receives a sampling starting instruction issued by a wireless access master station, the sampling module samples and stores sampling data into a storage area 1, after the wireless module receives a triggering completion instruction issued by the wireless access master station, the wireless module stops storing AD data into the storage area 1 and records the position of a pointer 1 at the moment, wherein the position of the pointer 1 at the moment is the byte number N1 of 4 bytes of data of all 4 channels and each channel corresponding to the current sampling rate Sr and sampling backtracking time Tb, namely N1 is Sr Tb 4; then, storing the AD conversion result in the storage area 2, where the storage area 2 is a byte number N2 of 4 bytes of data of all 4 channels and each channel corresponding to the current sampling rate Sr and the sampling time Ts, that is, N2 is Sr × Ts 4 × 4, the storage area 2 reserves a required space N1 for the trace-back data at the start, the data storage pointer 2 moves backward from N1 of the storage area 2, and when the data storage pointer moves to the end of the storage area 2, indicating that the sampling time Ts has been reached, the wireless acquisition terminal stops sampling, and at this time, the byte number N3 of the data stored in the storage area 2 is Sr × Tc 4;

rearranging the data with the length of N1 in the storage area 1 according to the time sequence and copying the data to the initial position of the storage area 2 according to the stop position of the pointer 1 when the trigger instruction is received; at this time, the data in the storage area 2 is the sum of the data N1 corresponding to the sampling backtracking time Tb and the data N3 corresponding to the triggered sampling time Tc, that is, the data N2 corresponding to the sampling time Ts.

3. A tunnel active source seismic wave wireless acquisition method is characterized by comprising the following steps:

receiving a sampling starting instruction issued by a wireless access master station, and performing AD sampling on the output of a detector after receiving the sampling starting instruction;

storing the sampled AD data in the storage area 1;

after receiving a trigger completion instruction issued by the wireless access master station, stopping storing the AD data into the storage area 1, recording the position of the pointer 1 at the moment, and then starting storing the AD conversion result into the storage area 2; where storage area 2 reserves the required space for the trace-back data at the beginning, N1, data store pointer 2 moves backward from storage area 2, N1;

stopping sampling after sampling time Ts;

rearranging the data with the length of N1 in the storage area 1 according to the time sequence and copying the data to the initial position of the storage area 2 according to the stop position of the pointer 1 when the trigger instruction is received;

receiving an uploading data instruction sent by an upper computer;

and uploading the sampling data of the storage area 2 to an upper computer.

4. A wireless acquisition system for seismic waves of a tunnel active source is characterized in that: the wireless acquisition system comprises an upper computer, a wireless access master station and a plurality of wireless acquisition terminals, wherein the upper computer is connected with the wireless access master station, the wireless access master station is in communication connection with at least one wireless acquisition terminal in a wireless mode, and the wireless acquisition terminals are the wireless acquisition terminals in the claims 1 or 2.

5. A wireless acquisition system of seismic waves of a tunnel active source according to claim 4, wherein the wireless acquisition terminal executes the wireless acquisition method of claim 3.

6. The system for wirelessly acquiring seismic waves of a tunnel active source according to any one of claims 4 to 5, wherein: the wireless acquisition terminal also comprises a detector externally arranged in the terminal protection box; the control module is respectively connected with the sampling module, the CPLD module, the wireless module, the power module and the clock module and is used for finishing AD sampling control and sampling data storage of the detector, sending and receiving of the wireless module and power management of the power module; the geophone is used for collecting seismic wave signals in the x/y/z directions and transmitting current signals to the AD module in an aerial plug mode; the sampling module converts a current signal into serial shift data, and the CPLD module converts the serial shift data into parallel data and transmits the parallel data to the control module for reading; the power supply module is used for providing power supply for the whole wireless acquisition terminal; the clock module is used for providing a high-precision external clock source for the control module and the sampling module.

7. The wireless acquisition system of seismic waves of a tunnel active source according to claim 6, wherein the sampling module comprises a signal conditioning circuit and an AD chip, the signal conditioning circuit converts a current signal output by the geophone into a voltage signal, and then sends the voltage signal to the AD chip; the AD chip is a four-channel synchronous sampling AD converter, a first channel is used for converting an x-axis seismic wave signal, a second channel is used for converting a y-axis seismic wave signal, a third channel is used for converting a z-axis seismic wave signal, a fourth channel is used for converting a noise signal, and the noise signal can eliminate interference introduced by the wireless acquisition terminal when processing data; the CPLD module is used for converting the four paths of serial shift data synchronously output by the sampling module into parallel data.

8. A computer readable storage medium, having stored thereon a computer program, characterized in that the program, when being executed by a processor, realizes the steps of the method for wireless acquisition of tunnel active source seismic waves according to claim 3.

Technical Field

The invention relates to the technical field of tunnel engineering, in particular to a method, a system and a terminal for wirelessly acquiring seismic waves of a tunnel active source.

Background

In the tunnel construction process, in order to guarantee the construction safety, whether unfavorable geologic bodies such as faults, water-bearing bodies, broken zones and the like exist in front of the tunnel face needs to be ascertained in advance, otherwise potential safety hazards can be caused. At present, tunnel geological advanced prediction is carried out by using a seismic wave advanced detection method, which is one of the most common and effective methods for detecting poor geologic bodies, and generally, an active source (also called an artificial seismic source, such as a sledge hammer, a hydraulic seismic source, a pneumatic seismic source and the like) is adopted to excite seismic waves on the side wall of a tunnel, a wave detector and a signal acquisition system are used for recording seismic wave signals, and then further analysis and inversion are carried out, so that the geological condition in front of the tunnel is reflected. The most front link of the method is how to accurately, efficiently and conveniently detect high-quality seismic signal data.

In the prior art, some detection systems are connected with a seismic signal detector and a collection host in a wired manner. Although the technology of wired connection is relatively mature, the output signal of the detector is a voltage type or current type analog signal, and is inevitably subjected to electromagnetic interference of equipment such as tunnel construction site electric welding machines and construction machinery when being transmitted on a long cable which is as long as tens of meters, so that the interference signal and a useful signal are superposed. In addition, a large number of constructors are needed to perform operations such as wiring, wire collection and the like, so that the construction efficiency is low; and the cable is subject to wear, resulting in increased cost.

Therefore, there is a need for a seismic acquisition system that uses wireless data transmission to accomplish the acquisition, storage, and transmission of data. However, the problems of the prior art seismic wave wireless acquisition system are as follows: firstly, the sampling precision and the sampling rate are low, and the seismic waveform cannot be accurately restored; secondly, seismic wave data in the x/y/z directions of the tunnel cannot be acquired only by adopting a single-component detector; and the problems of trigger delay and synchronization among a plurality of wireless acquisition terminals are not considered.

Disclosure of Invention

Aiming at the requirements and the defects of the prior art development, the invention provides a method, a system and a terminal for wirelessly acquiring seismic waves of a tunnel active source.

The invention discloses a wireless acquisition terminal for seismic waves of a tunnel active source, which comprises:

the control module is used for managing the wireless module, the sampling module, the delay eliminating module, the data storage module, the power supply module, the clock module and the CPLD module and reading the sampled data;

the wireless module is used for carrying out wireless communication with the wireless access master station and the upper computer, and comprises a function of receiving a sampling starting instruction or a triggering completion instruction sent by the wireless access master station or receiving a data uploading instruction sent by the upper computer and transmitting data to the upper computer;

the sampling module is used for carrying out AD sampling on the output of the detector after receiving a sampling starting instruction or a triggering completion instruction;

the time delay elimination module comprises a time recording module and a data processing module;

the time recording module is used for recording sampling time Ts and sampling backtracking time Tb, and subtracting the sampling backtracking time Tb from the sampling time Ts, namely Tc is Ts-Tb;

the data processing module comprises a storage area 1 and a storage area 2, and is used for storing the sampling data within the sampling backtracking time Tb after the wireless module receives the sampling starting instruction in the storage area 1 and storing the sampling data within the whole sampling time Ts of the wireless module in the storage area 2.

After the wireless module receives a sampling starting instruction issued by a wireless access master station, the sampling module samples and stores sampling data into a storage area 1, after the wireless module receives a triggering completion instruction issued by the wireless access master station, the wireless module stops storing AD data into the storage area 1 and records the position of a pointer 1 at the moment, wherein the position of the pointer 1 at the moment is the byte number N1 of 4 bytes of data of all 4 channels and each channel corresponding to the current sampling rate Sr and sampling backtracking time Tb, namely N1 is Sr Tb 4; then, storing the AD conversion result in the storage area 2, where the storage area 2 is a byte number N2 of 4 bytes of data of all 4 channels and each channel corresponding to the current sampling rate Sr and the sampling time Ts, that is, N2 is Sr × Ts 4 × 4, the storage area 2 reserves a required space N1 for the trace-back data at the start, the data storage pointer 2 moves backward from N1 of the storage area 2, and when the data storage pointer moves to the end of the storage area 2, indicating that the sampling time Ts has been reached, the wireless acquisition terminal stops sampling, and at this time, the byte number N3 of the data stored in the storage area 2 is Sr × Tc 4;

rearranging the data with the length of N1 in the storage area 1 according to the time sequence and copying the data to the initial position of the storage area 2 according to the stop position of the pointer 1 when the trigger instruction is received; at this time, the data in the storage area 2 is the sum of the data N1 corresponding to the sampling backtracking time Tb and the data N3 corresponding to the triggered sampling time Tc, that is, the data N2 corresponding to the sampling time Ts.

A wireless acquisition method for seismic waves of a tunnel active source comprises the following steps:

receiving a sampling starting instruction issued by a wireless access master station, and performing AD sampling on the output of a detector after receiving the sampling starting instruction;

storing the sampled AD data in the storage area 1;

after receiving a trigger completion instruction issued by the wireless access master station, stopping storing the AD data into the storage area 1, recording the position of the pointer 1 at the moment, and then starting storing the AD conversion result into the storage area 2; where storage area 2 reserves the required space for the trace-back data at the beginning, N1, data store pointer 2 moves backward from storage area 2, N1;

stopping sampling after sampling time Ts;

rearranging the data with the length of N1 in the storage area 1 according to the time sequence and copying the data to the initial position of the storage area 2 according to the stop position of the pointer 1 when the trigger instruction is received;

receiving an uploading data instruction sent by an upper computer;

and uploading the sampling data of the storage area 2 to an upper computer.

A wireless acquisition system for seismic waves of a tunnel active source comprises an upper computer, a wireless access master station and a plurality of wireless acquisition terminals, wherein the upper computer is connected with the wireless access master station, the wireless access master station is in communication connection with at least one wireless acquisition terminal in a wireless mode, and the wireless acquisition terminal is as claimed in claim 1 or claim 2.

The wireless acquisition terminal executes the wireless acquisition method.

The wireless acquisition terminal also comprises a detector externally arranged in the terminal protection box; the control module is respectively connected with the sampling module, the CPLD module, the wireless module, the power module and the clock module and is used for finishing AD sampling control and sampling data storage of the detector, sending and receiving of the wireless module and power management of the power module; the geophone is used for collecting seismic wave signals in the x/y/z directions and transmitting current signals to the AD module in an aerial plug mode; the sampling module converts a current signal into serial shift data, and the CPLD module converts the serial shift data into parallel data and transmits the parallel data to the control module for reading; the power supply module is used for providing power supply for the whole wireless acquisition terminal; the clock module is used for providing a high-precision external clock source for the control module and the sampling module.

The sampling module comprises a signal conditioning circuit and an AD chip, wherein the signal conditioning circuit converts a current signal output by the detector into a voltage signal and then sends the voltage signal to the AD chip; the AD chip is a four-channel synchronous sampling AD converter, a first channel is used for converting an x-axis seismic wave signal, a second channel is used for converting a y-axis seismic wave signal, a third channel is used for converting a z-axis seismic wave signal, a fourth channel is used for converting a noise signal, and the noise signal can eliminate interference introduced by the wireless acquisition terminal when processing data; the CPLD module is used for converting the four paths of serial shift data synchronously output by the sampling module into parallel data.

A computer readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out the steps of the method for wireless acquisition of seismic waves of a tunnel active source.

Further, a wireless acquisition method of seismic waves of a tunnel active source is realized based on an upper computer, a wireless access master station and a plurality of wireless acquisition terminals, and the realization process comprises the following steps:

s1, the upper computer is in communication connection with a wireless access master station in a USB mode, and the wireless access master station is in communication connection with at least one wireless acquisition terminal in a wireless mode;

step S2, setting sampling parameters through an upper computer according to actual engineering requirements, wherein the sampling parameters comprise a sampling rate Sr, sampling time Ts, sampling backtracking time Tb and triggering sensitivity, and the triggered sampling time Tc is obtained by subtracting the sampling backtracking time Tb from the sampling time Ts, namely Tc is Ts-Tb;

step S3, starting sampling, wherein the wireless access master station carries out AD sampling on the output of a trigger sensor fixed on an artificial seismic source and issues a sampling starting instruction to all the accessed wireless acquisition terminals, and all the wireless acquisition terminals carry out AD sampling on the output of a detector after receiving the sampling starting instruction so as to ensure the synchronism of the sampling starting of all the wireless acquisition terminals;

step S4, after the artificial seismic source is excited, the wireless access master station reads the AD sampling result of the trigger sensor, when the AD sampling result exceeds a set trigger threshold value, the wireless access master station sends trigger completion instructions to all wireless acquisition terminals, and meanwhile, the wireless access master station uploads the trigger completion instructions to an upper computer;

step S5, timing is started after the upper computer receives the trigger completion instruction, and the wireless acquisition terminal completes sampling after sampling time Ts;

and S6, the upper computer sequentially sends data uploading instructions to the accessed wireless acquisition terminals, the wireless acquisition terminals upload the stored AD sampling data to the upper computer, and the upper computer stores and analyzes the received data and displays the waveforms of the wireless acquisition terminals and the channels.

In the process of executing step S3-step S5, after the sampling is started and before the triggering is completed, the wireless acquisition terminal stores the AD data in the storage area 1, where the size of the storage area 1 is N1, which is the number of bytes of 4-byte data of each channel, corresponding to all 4 channels and the sampling backtracking time Tb at the current sampling rate Sr, that is, N1 is Sr Tb 4; the data storage pointer 1 moves backwards from the beginning of the storage area 1, and jumps to the beginning after moving to the end of the storage area 1, namely, the data is circularly covered in the storage area 1.

In the process of executing the step S4, the radio access master station issues a trigger completion instruction to all the radio acquisition terminals, and then all the radio acquisition terminals receive the trigger completion instruction, stop storing the AD data in the storage area 1, record the position of the pointer 1 at this time, and then start storing the AD conversion result in the storage area 2, where the storage area 2 is the byte number N2 of 4 bytes of data of all 4 channels and each channel corresponding to the current sampling rate Sr and the sampling time Ts, that is, N2 is Sr Ts 4;

the storage area 2 reserves a required space N1 for backtracking data at the beginning, the data storage pointer 2 moves backwards from N1 of the storage area 2, when the data storage pointer moves to the end of the storage area 2, which indicates that the sampling time Ts is reached, the wireless acquisition terminal stops sampling, and at this time, the byte number N3 of the data stored in the storage area 2 is Sr Tc 4;

after the wireless acquisition terminal stops sampling, rearranging and copying data with the length of N1 in the storage area 1 to the start of the storage area 2 according to the time sequence according to the stop position of the pointer 1 when the trigger instruction is received; at this time, the data in the storage area 2 is the sum of the data N1 corresponding to the sampling backtracking time Tb and the data N3 corresponding to the triggered sampling time Tc, that is, the data N2 corresponding to the sampling time Ts.

Optionally, the related wireless access master station comprises a master station protection box, a first MCU module, a first signal conditioning module, a first wireless module, a first USB module, a first power module, a first clock module and a trigger sensor, wherein the first MCU module, the first signal conditioning module, the first wireless module, the first USB module, the first power module and the first clock module are arranged in the master station protection box, and the trigger sensor is arranged outside the master station protection box; the MCU module is respectively connected with the signal conditioning module, the wireless module I, the USB module, the power module I and the clock module I and is used for finishing AD sampling control and sampling data storage of the trigger sensor, sending and receiving of the wireless module I, sending and receiving of the USB module and power management of the power module I; the trigger sensor is used for being fixed on the artificial seismic source and sending a current signal to the signal conditioning module; the signal conditioning module is used for converting the current signal into a voltage signal and then sending the voltage signal to the MCU module I; the MCU module carries out AD conversion on the voltage signals and judges whether the AD data exceed a set threshold value or not, when the AD data exceed the set threshold value, the MCU module issues a trigger completion instruction to a plurality of wireless acquisition terminals one by one through the wireless module, and sends the trigger completion instruction to an upper computer through the USB module; the power supply module I is used for providing power supply for the whole wireless access master station; the clock module I is used for providing a high-precision external clock source for the MCU module I;

the wireless access master station further comprises a first SRAM module, the first SRAM module is used for expanding the memory space of the first MCU module to store the sampling data of the trigger sensor before and after the triggering of the artificial seismic source, and the first SRAM module is also used for operating the memory of the first MCU module.

Further optionally, the related wireless acquisition terminal comprises a terminal protection box, a second MCU module, an AD module, a CPLD module, a second wireless module, a second power module, a second clock module, and a detector externally disposed on the terminal protection box, wherein the second MCU module, the AD module, the CPLD module, the second wireless module, the second power module, and the second clock module are disposed in the terminal protection box; the MCU module II is respectively connected with the AD module, the CPLD module, the wireless module II, the power module II and the clock module II and is used for finishing AD sampling control and sampling data storage of the detector, sending and receiving of the wireless module II and power management of the power module II; the geophone is used for collecting seismic wave signals in the x/y/z directions and transmitting current signals to the AD module in an aerial plug mode; the AD module converts the current signal into serial shift data, and the CPLD module converts the serial shift data into parallel data and transmits the parallel data to the MCU module II for reading; the power supply module II is used for providing power supply for the whole wireless acquisition terminal; the clock module II is used for providing a high-precision external clock source for the MCU module II and the AD module;

the wireless acquisition terminal further comprises a second SRAM module, the second SRAM module comprises a storage area 1 and a storage area 2, the second SRAM module is used for expanding the memory space of the second MCU module to store the AD data of the detectors and the noise channels before and after the triggering of the artificial seismic source, and the second SRAM module is also used for operating the memory of the second MCU module.

Further optionally, the related AD module includes a signal conditioning circuit and an AD chip, and the signal conditioning circuit converts the current signal output by the detector into a voltage signal and then sends the voltage signal to the AD chip; the AD chip is a 24-bit four-channel synchronous sampling AD converter, a first channel is used for converting an x-axis seismic wave signal, a second channel is used for converting a y-axis seismic wave signal, a third channel is used for converting a z-axis seismic wave signal, a fourth channel is used for converting a noise signal, and the noise signal can eliminate interference introduced by the wireless acquisition terminal when processing data; each channel has 8-bit data check besides the 24-bit AD conversion result, that is, each channel outputs 32-bit serial shift data in each conversion;

the CPLD module is used for converting the four paths of 32-bit serial shift data synchronously output by the AD module into parallel data.

Preferably, the power supply module comprises a 3.3V power supply used by a digital circuit, a 5V power supply used by an analog circuit and a 24V power supply used by a trigger sensor;

the power supply module comprises a 3.3V power supply used by a digital circuit, a 5V power supply used by an analog circuit and a 24V power supply used by a detector; the power supply module II is powered by a built-in rechargeable lithium battery pack, the battery voltage of the rechargeable lithium battery pack is divided and then sent to the MCU module II, and the MCU module II reads the battery voltage in real time and uploads the battery voltage to the upper computer; and when sampling is not needed temporarily, the second MCU module controls to close the 5V power supply and the 24V power supply so as to prolong the standby time of the wireless acquisition terminal.

Preferably, the first wireless module and the second wireless module respectively adopt 2.4G radio frequency wireless transceiver chips;

the first wireless module is used for carrying out two-way communication with the wireless acquisition terminal so as to realize control instruction sending, instruction response receiving and seismic wave sampling data;

and the second wireless module is used for carrying out bidirectional communication with the wireless access master station so as to receive control instructions, send instruction responses and seismic wave sampling data.

Preferably, the first wireless module and the second wireless module respectively comprise a radio frequency transmission power amplifying circuit, a reception power amplifying circuit and an external antenna.

Compared with the prior art, the tunnel active source seismic wave wireless acquisition method has the beneficial effects that:

(1) the invention adopts a wireless mode to transmit control instructions and seismic wave sampling data, does not need to lay cables, can freely arrange the number and the positions of wireless acquisition terminals, can synchronously start sampling and synchronous triggering of all the wireless acquisition terminals, ensures the time consistency of each wireless acquisition terminal, has the characteristics of convenient carrying and installation, high sampling precision and sampling rate, adaptability to different artificial sources, good synchronism, capability of backtracking the sampling data before triggering and the like, and can meet the requirements of tunnel construction environment;

(2) the invention can collect seismic wave signals in three directions of x/y/z and a path of noise signals, the sampling precision is 24 bits, the highest sampling rate supports 64kSPS, high-quality seismic wave original signals can be collected, and the noise signals can be used for eliminating the interference introduced by the wireless collection terminal;

(3) the method can backtrack the sampling data before the triggering of the wireless acquisition terminal, eliminate the time delay caused by signal transmission from the actual triggering of the artificial seismic source to the receiving of the triggering completion instruction by the wireless acquisition terminal, and prevent the data from being lost.

Drawings

FIG. 1 is a connection block diagram of the method implementation of the present invention;

FIG. 2 is a block diagram of the structural connection of the wireless access master station in the present invention;

FIG. 3 is a block diagram of the structural connection of the wireless acquisition terminal of the present invention;

FIG. 4 is a schematic diagram of a second SRAM module of the present invention for storing data.

The reference information in the drawings indicates:

1. the system comprises an upper computer 2, a wireless access master station 3 and a wireless acquisition terminal;

2-1, a first MCU module, 2-2, a trigger sensor, 2-3, a signal conditioning module, 2-4 and a first SRAM module,

2-5 parts of a first wireless module, 2-6 parts of a USB module, 2-7 parts of a first power supply module, 2-8 parts of a first clock module;

3-1, a second MCU module, 3-2, a detector, 3-3, an AD module, 3-4 and a CPLD module,

3-5 parts of SRAM module II, 3-6 parts of SRAM module II, 3-7 parts of wireless module II, 3-8 parts of power module II and clock module II.

Detailed Description

In order to make the technical scheme, the technical problems to be solved and the technical effects of the present invention more clearly apparent, the following technical scheme of the present invention is clearly and completely described with reference to the specific embodiments.

The first embodiment is as follows:

with reference to fig. 1-4, the present embodiment provides a method for wirelessly acquiring seismic waves of a tunnel active source, where the implementation is based on an upper computer 1, a wireless access master station 2, and multiple wireless acquisition terminals 3, the upper computer 1 and the wireless access master station 2 are connected through a USB interface and communicate, and the wireless access master station 2 and each wireless acquisition terminal 3 communicate in a wireless manner. In this embodiment, the number of the wireless acquisition terminals 3 is not more than 12.

The upper computer 1 is a general name of a computer (usually a notebook computer or an industrial personal computer) and software, and has the main functions of: sending control instructions to the wireless access master station 2 and the wireless acquisition terminal 3, receiving and processing the response of the control instructions, receiving and storing seismic wave sampling data and displaying seismic waveforms.

The implementation process of the wireless acquisition method for seismic waves of the tunnel active source in the embodiment comprises the following steps:

step S1, the upper computer 1 is in communication connection with the wireless access master station 2 in a USB mode, and the wireless access master station 2 is in communication connection with at least one wireless acquisition terminal 3 in a wireless mode;

step S2, setting sampling parameters through the upper computer 1 according to actual engineering requirements, wherein the sampling parameters comprise a sampling rate Sr, a sampling time Ts, a sampling backtracking time Tb and a trigger sensitivity, generally speaking, the sampling rate Sr supports 1k, 2k, 4k, 8k, 16k, 32k and 64k, and the corresponding sampling intervals are 1ms, 0.5ms, 0.25ms, 0.125ms, 62.5us, 31.25us and 15.625us respectively; the maximum settable sampling time Ts is inversely proportional to the sampling rate Sr, and at 8k sampling rate, the settable sampling time ranges from 1ms to 16384ms, and is usually set to n-th power ms of 2, such as 512ms, 1024ms, and the like; sampling backtracking time Tb, namely the time for caching the sampling data before the wireless acquisition terminal 3 receives the trigger signal, wherein the settable range is 0-16 ms, and the sampling time Tc after triggering is the sampling time Ts minus the sampling backtracking time Tb, namely Tc is Ts-Tb; the trigger sensitivity can be set to be five gears of ultra-high, medium, low and ultra-low according to different types of artificial seismic sources or different use environments, so that the trigger sensor 2-2 can be triggered only when the artificial seismic sources are actually excited, and false triggering can be effectively avoided;

step S3, starting sampling, wherein the wireless access master station 2 carries out AD sampling on the output of a trigger sensor 2-2 fixed on an artificial seismic source and issues a sampling starting instruction to all the wireless acquisition terminals 3 which are accessed, and all the wireless acquisition terminals 3 carry out AD sampling on the output of a detector 3-2 after receiving the sampling starting instruction so as to ensure the synchronization of the sampling starting of all the wireless acquisition terminals 3;

step S4, after the artificial seismic source is excited, the wireless access master station 2 reads the AD sampling result of the trigger sensor 2-2, when the AD sampling result exceeds a set trigger threshold, the wireless access master station 2 issues trigger completion instructions to all the wireless acquisition terminals 3, and meanwhile, the wireless access master station 2 uploads the trigger completion instructions to the upper computer 1;

step S5, the upper computer 1 starts timing after receiving the trigger completion instruction, and the wireless acquisition terminal 3 completes sampling after sampling time Ts;

step S6, the upper computer 1 sequentially sends data uploading instructions to the accessed wireless acquisition terminals 3, the wireless acquisition terminals 3 upload the stored AD sampling data to the upper computer 1, and the upper computer 1 stores and analyzes the received data and displays the waveforms of the wireless acquisition terminals 3 and the channels.

In the process of executing step S3-step S5, after the sampling is started and before the triggering is completed, the wireless acquisition terminal 3 stores the AD data in the storage area 1, where the size of the storage area 1 is N1, which is the number of bytes of 4-byte data of each channel, corresponding to all 4 channels and the sampling backtracking time Tb at the current sampling rate Sr, that is, N1 is Sr Tb 4 × 4; the data storage pointer 1 moves backwards from the beginning of the storage area 1, and jumps to the beginning after moving to the end of the storage area 1, namely, the data is circularly covered in the storage area 1.

In the process of executing step S4, the primary radio access station 2 issues a trigger completion instruction to all the wireless acquisition terminals 3, and then all the wireless acquisition terminals 3 receive the trigger completion instruction, stop storing the AD data in the storage area 1, record the position of the pointer 1 at this time, and then start storing the AD conversion result in the storage area 2, where the storage area 2 is the byte number N2 of 4 bytes of data of all 4 channels and each channel corresponding to the current sampling rate Sr and the sampling time Ts, that is, N2 is Sr Ts 4;

the storage area 2 reserves a required space N1 for backtracking data at the beginning, the data storage pointer 2 moves backwards from N1 of the storage area 2, when the data storage pointer moves to the end of the storage area 2, which indicates that the sampling time Ts is reached, the wireless acquisition terminal stops sampling, and at this time, the byte number N3 of the data stored in the storage area 2 is Sr Tc 4;

after the wireless acquisition terminal 3 stops sampling, rearranging and copying the data with the length of N1 in the storage area 1 to the start of the storage area 2 according to the time sequence according to the stop position of the pointer 1 when the trigger instruction is received; at this time, the data in the storage area 2 is the sum of the data N1 corresponding to the sampling backtracking time Tb and the data N3 corresponding to the triggered sampling time Tc, that is, the data N2 corresponding to the sampling time Ts.

In the embodiment, the wireless access master station 2 comprises a master station protection box, a first MCU module 2-1, a signal conditioning module 2-3, a first wireless module 2-5, a USB module 2-6, a first power module 2-7, a first clock module 2-8 and a trigger sensor 2-2, wherein the first MCU module, the signal conditioning module, the first wireless module, the USB module 2-6, the first power module 2-7 and the first clock module are arranged in the master station protection box. The MCU module I2-1 is respectively connected with the signal conditioning module I2-3, the wireless module I2-5, the USB module I2-6, the power module I2-7 and the clock module I2-8 and is used for finishing AD sampling control and sampling data storage of the trigger sensor 2-2, sending and receiving of the wireless module I2-5, sending and receiving of the USB module I2-6 and power management of the power module I2-7. The trigger sensor 2-2 is a single-axis acceleration sensor, is fixed on the artificial seismic source, is connected to the signal conditioning module 2-3 through an external cable and an aviation plug, and sends a current signal to the signal conditioning module 2-3. The signal conditioning module 2-3 is used for converting the current signal into a voltage signal and then sending the voltage signal to the MCU module I2-1. The MCU module I2-1 carries out AD conversion on the voltage signal and judges whether the AD data exceed a set threshold value or not, and when the AD data exceed the set threshold value, the MCU module I2-1 sends a trigger completion instruction to the wireless acquisition terminals 3 through the wireless modules I2-5 on one hand, and sends the trigger completion instruction to the upper computer 1 through the USB modules 2-6 on the other hand. The power supply module I2-7 is used for supplying power to the whole wireless access master station 2, and the power supply module I2-7 comprises a 3.3V power supply used by a digital circuit, a 5V power supply used by an analog circuit and a 24V power supply used by the trigger sensor 2-2. The clock module I2-8 adopts a temperature compensation active crystal oscillator, the frequency precision is better than 0.1ppm, and the clock module I2-8 is used for providing a high-precision external clock source for the MCU module I2-1.

In this embodiment, the wireless access master station 2 further includes a SRAM module one 2-4, the SRAM module one 2-4 is used to expand a memory space of the MCU module one 2-1 to store sampling data of the trigger sensor 2-2 before and after triggering of the artificial seismic source, and the SRAM module one 2-4 is also used to operate a memory of the MCU module one 2-1.

In the embodiment, the wireless acquisition terminal 3 comprises a terminal protection box, a second MCU module 3-1, a second AD module 3-3, a CPLD module 3-4, a second wireless module 3-6, a second power module 3-7, a second clock module 3-8 and a second detector 3-2 which is arranged outside the terminal protection box, wherein the second MCU module, the second AD module, the second CPLD module, the second wireless module, the second power module and the second clock module are arranged inside the terminal protection box. The MCU module II 3-1 is respectively connected with the AD module 3-3, the CPLD module 3-4, the wireless module II 3-6, the power module II 3-7 and the clock module II 3-8 and is used for finishing AD sampling control and sampling data storage of the detector 3-2, sending and receiving of the wireless module II 3-6 and power management of the power module II 3-7. The geophone 3-2 adopts a three-axis acceleration sensor for collecting seismic wave signals in the x/y/z directions, is connected to the AD module 3-3 through an external cable and an aviation plug, and transmits current signals to the AD module 3-3. The AD module 3-3 comprises a signal conditioning circuit and an AD chip, wherein the signal conditioning circuit converts a current signal output by the wave detector 3-2 into a voltage signal and then sends the voltage signal to the AD chip; the AD chip is a 24-bit four-channel synchronous sampling AD converter, a first channel is used for converting an x-axis seismic wave signal, a second channel is used for converting a y-axis seismic wave signal, a third channel is used for converting a z-axis seismic wave signal, a fourth channel is used for converting a noise signal, and the noise signal can eliminate interference introduced by the wireless acquisition terminal 3 when processing data; each channel has 8-bit data check in addition to the 24-bit AD conversion result, i.e., each channel outputs 32-bit serial shift data per conversion. The CPLD module 3-4 is used for converting four paths of 32-bit serial shift data synchronously output by the AD module 3-3 into parallel data and transmitting the parallel data to the MCU module II 3-1 for reading. The power supply module II 3-7 is used for providing power supply for the whole wireless acquisition terminal 3, and comprises a 3.3V power supply used by a digital circuit, a 5V power supply used by an analog circuit and a 24V power supply used by the detector 3-2; the power supply module II 3-7 adopts a built-in rechargeable lithium battery pack to supply power, the battery voltage of the rechargeable lithium battery pack is divided and then sent to the MCU module II 3-1, and the MCU module II 3-1 reads the battery voltage in real time and uploads the battery voltage to the upper computer 1; and when sampling is not needed temporarily, the MCU module II 3-1 controls to close the 5V power supply and the 24V power supply so as to prolong the standby time of the wireless acquisition terminal 3. The clock module II 3-8 adopts a temperature compensation active crystal oscillator, the frequency precision is better than 0.1ppm, and the clock module II 3-8 is used for providing a high-precision external clock source for the MCU module II 3-1 and the AD module 3-3 so as to avoid sampling data asynchronization caused by clock accumulated errors to the maximum extent during the sampling period of the AD module 3-3.

In this embodiment, the wireless acquisition terminal 3 further includes a second SRAM module 3-5, the second SRAM module 3-5 further includes a storage area 1 and a storage area 2, and the sizes of the storage area 1 and the storage area 2 are dynamically allocated by the second MCU module 3-1. The SRAM module II 3-5 is used for expanding the memory space of the MCU module II 3-1 to store AD data of the wave detector 3-2 and the noise channel before and after triggering of the artificial seismic source, and the SRAM module II 3-5 is also used for operating the memory of the MCU module II 3-1.

In the wireless access master station 2 and the wireless acquisition terminal 3 of this embodiment, the first wireless modules 2 to 5 and the second wireless modules 3 to 6 respectively adopt 2.4G radio frequency wireless transceiver chips, wherein: the wireless modules I2-5 are used for carrying out bidirectional communication with the wireless acquisition terminal 3 so as to realize control instruction sending, instruction response receiving and seismic wave sampling data; and the second wireless module 3-6 is used for carrying out bidirectional communication with the wireless access master station 2 so as to receive control instructions, send instruction responses and seismic wave sampling data. Certainly, the first wireless modules 2 to 5 and the second wireless modules 3 to 6 further include a radio frequency transmission power amplifying circuit, a reception power amplifying circuit and an external antenna respectively, and are used for improving radio frequency transmission and reception power and increasing communication distance of wireless communication.

It is to be supplemented that the AD chips of the MCU module two 3-1, the CPLD module 3-4, the SRAM module two 3-5, the wireless module two 3-6, and the AD module 3-3 are integrated on one circuit board, and the signal conditioning circuit of the AD module 3-3 and the power module two 3-7 are integrated on another circuit board, which can effectively reduce the interference between the analog circuit and the digital circuit, and can also achieve a miniaturized design, reducing the design size of the terminal protection box of the wireless acquisition terminal 3.

A computer readable storage medium, on which a computer program is stored, which program, when being executed by a processor, carries out the steps of the method for wireless acquisition of seismic waves of a tunnel active source.

In summary, the tunnel active source seismic wave wireless acquisition method has the characteristics of convenience in carrying and installation, high sampling precision and sampling rate, adaptability to different artificial seismic sources, good synchronism, capability of backtracking sampling data before triggering and the like, and can meet the requirements of tunnel construction environments.

The principles and embodiments of the present invention have been described in detail using specific examples, which are provided only to aid in understanding the core technical content of the present invention. Based on the above embodiments of the present invention, those skilled in the art should make any improvements and modifications to the present invention without departing from the principle of the present invention, and therefore, the present invention should fall into the protection scope of the present invention.