A monitor

Abstract

The application discloses a kind of monitoring instruments, including outer probe rod, pressure-resistant cabin, baffle, differential pressure sensor and temperature sensor;Baffle is arranged in the inside of the outer probe rod, baffle is used to divide the internal cavity of outer probe rod into first cavity and second cavity, and outer probe rod is used to insert seabed deposit;Pressure-resistant cabin is arranged at the top of outer probe rod, and circuit board is arranged in the inside of pressure-resistant cabin, differential pressure sensor is arranged in first cavity and is connected with circuit board, temperature sensor is arranged in second cavity and is connected with circuit board, differential pressure sensor is used to output differential pressure signal, and temperature sensor is used to output temperature signal;Circuit board is used to monitor seabed deposit according to differential pressure signal and temperature signal.The monitoring instrument provided by the application can realize differential pressure monitoring.

Description

Technical Field

[0001] This invention relates to the field of deep-sea monitoring technology, and in particular to a monitoring instrument. Background Technology

[0002] Submarine cold seep monitoring is a key method for understanding and utilizing deep-sea resources. Cold seeps refer to low-temperature fluids that flow into a basin from below the seafloor sedimentary interface through gushing and seepage. Areas with active cold seeps typically indicate the enrichment of natural gas hydrates (a new energy resource with enormous potential). Natural gas hydrates form in low-temperature, high-pressure environments, and sediment temperature and pressure conditions significantly influence their distribution within strata. The stable zone of natural gas hydrates refers to the stratigraphic depth range that meets the necessary physical (temperature, pressure) conditions for their existence. Determining the distribution of stable zones is beneficial for macroscopically understanding potential production areas. In the assessment of natural gas hydrate resources, the thickness of the stable zone is an essential parameter.

[0003] Currently, in hydrate research, the seabed is typically considered the upper limit of the hydrate stability zone. This allows for the determination of hydrate stability by studying seabed temperature and pressure conditions, thereby defining the stable range of hydrates on a plane. When determining the lower boundary of the hydrate stability zone, given the seabed temperature and water depth, the temperature is extrapolated using the geothermal gradient and then compared with the hydrate stability phase diagram to arrive at the lower boundary. For cold seep areas, existing instruments for measuring the temperature and pressure of seabed sediments generally use an extension rod inserted into the sediment. Temperature and pressure are detected by temperature and pressure probes. A sealed electronic chamber houses an inclinometer, accelerometer, communication module, data acquisition module, and power supply. The data acquisition module transmits data from the inclinometer, accelerometer, and temperature and pressure probes to data processing equipment on a winch via the communication module. However, using these instruments to monitor temperature and pressure data can lead to significant measurement errors due to the complex seabed environment. Summary of the Invention

[0004] This invention provides a monitoring instrument to solve the problem of large measurement errors in existing measuring instruments.

[0005] According to one aspect of the present invention, a monitoring instrument is provided, comprising an external probe, a pressure chamber, a partition, a differential pressure sensor, and a temperature sensor;

[0006] The partition is disposed inside the outer probe rod, and the partition is used to divide the internal cavity of the outer probe rod into a first cavity and a second cavity. The outer probe rod is used to insert into seabed sediments.

[0007] The pressure chamber is located at the top of the outer probe. A circuit board is installed inside the pressure chamber. The differential pressure sensor is located in the first cavity and connected to the circuit board. The temperature sensor is located in the second cavity and connected to the circuit board. The differential pressure sensor is used to output a differential pressure signal, and the temperature sensor is used to output a temperature signal. The circuit board is used to monitor the seabed sediments based on the differential pressure signal and the temperature signal.

[0008] Optionally, an insulating rod is also provided inside the second cavity, and the temperature sensor includes a thermistor, which is disposed on the insulating rod.

[0009] Optionally, the monitoring device further includes an attitude sensor mounted on top of the insulation rod, which is used to measure the attitude of the monitoring device.

[0010] Optionally, the circuit board includes an analog measurement module, a main control module, and a power supply module. The analog measurement module is connected to the differential pressure sensor and the temperature sensor. The main control module is connected to the analog measurement module. The power supply module is connected to both the main control module and the analog measurement module. The analog measurement module performs analog-to-digital conversion on the differential pressure signal and the temperature signal respectively and outputs digital signals. The main control module performs data processing based on the digital signals. The power supply module provides power to both the analog measurement module and the main control module.

[0011] Optionally, the analog measurement module includes a first bridge circuit, a second bridge circuit, a first noise reduction matching unit, a second noise reduction matching unit, a first analog-to-digital conversion unit, and a second analog-to-digital conversion unit. The first bridge circuit, the first noise reduction matching unit, and the first analog-to-digital conversion unit are connected in series between the differential pressure sensor and the main control module. The second bridge circuit, the second noise reduction matching unit, and the second analog-to-digital conversion unit are connected in series between the temperature sensor and the main control module.

[0012] Optionally, the power module includes a charge / discharge control unit, a lithium battery, and a reference voltage output unit. The charge / discharge control unit is connected between the lithium battery and the reference voltage output unit, and the reference voltage output unit is connected to the analog measurement module. The charge / discharge control unit is used to control the lithium battery to supply power to the reference voltage output unit, and the reference voltage output unit is used to provide a reference voltage to the analog measurement module.

[0013] Optionally, the monitoring device further includes a water inlet and a permeable mesh, wherein the water inlet is located at the top of the first cavity and the permeable mesh is located on the outer wall of the first cavity.

[0014] Optionally, the monitoring instrument also includes a cone, which is disposed at the bottom of the outer probe and is used to guide insertion into the seabed sediment.

[0015] Optionally, the monitoring instrument also includes a sealed welded pipe for connecting the outer probe and the pressure chamber.

[0016] Optionally, the monitoring instrument also includes a probe retaining ring and an anode post, the probe retaining ring being fixed to the outer probe, and the anode post being disposed on the upper surface of the pressure chamber.

[0017] The technical solution of this invention provides a monitoring instrument, including an outer probe, a pressure chamber, a partition, a differential pressure sensor, and a temperature sensor. The partition is disposed inside the outer probe, dividing the internal cavity of the outer probe into a first cavity and a second cavity. The outer probe is used to insert into seabed sediment. The pressure chamber is disposed at the top of the outer probe, and a circuit board is disposed inside the pressure chamber. The differential pressure sensor is disposed in the first cavity and connected to the circuit board, and the temperature sensor is disposed in the second cavity and connected to the circuit board. The differential pressure sensor outputs a differential pressure signal, and the temperature sensor outputs a temperature signal. The circuit board is used to monitor the seabed sediment based on the differential pressure signal and the temperature signal. The differential pressure signal output by the differential pressure sensor refers to the difference between the pore water pressure of the measured sediment and the hydrostatic pressure of the seabed, which can eliminate the influence of seabed current activity and tidal changes on pressure, and solve the problem of large measurement errors in existing measuring instruments.

[0018] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a structural diagram of a temperature and pressure measuring instrument in related technologies;

[0021] Figure 2 This is a schematic diagram of the structure of a monitoring instrument provided in an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of another monitoring instrument provided in an embodiment of the present invention;

[0023] Figure 4This is a schematic diagram of the circuit board structure provided in an embodiment of the present invention. Detailed Implementation

[0024] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0025] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0026] Submarine cold seep monitoring is a key method for understanding and utilizing deep-sea resources. Cold seeps refer to low-temperature fluids that emerge from below the seafloor sedimentary interface and flow into the basin via gushing and seeping, producing a series of physical, chemical, and biological processes. These phenomena and their products are called cold seeps. Submarine cold seeps are mainly composed of water, hydrocarbons (natural gas and oil), hydrogen sulfide, and fine-grained sediments. Their temperature is similar to that of seawater, and they are widely developed on the seafloor of active and passive continental margins and slopes. Submarine cold seep systems represent another new area of ​​fluid sedimentation following the discovery and study of mid-ocean ridge hydrothermal vents. Cold seep activity areas typically indicate the enrichment of natural gas hydrates (a new energy resource with great potential). Natural gas hydrates form in low-temperature, high-pressure environments, and sediment temperature and pressure conditions significantly influence the distribution of hydrates within the strata. The stable zone of natural gas hydrates refers to the stratigraphic depth range that meets the necessary physical (temperature, pressure) conditions for the existence of natural gas hydrates; determining the distribution of the stable zone of natural gas hydrates is beneficial for macroscopically understanding the potential production areas of natural gas hydrates. In the assessment of natural gas hydrate resources, the thickness of the hydrate stability zone is an essential parameter. Currently, in hydrate research, the seabed is typically considered as the upper limit of the hydrate stability zone. Thus, studying the temperature and pressure conditions on the seabed can determine whether the hydrate is stable, thereby delineating the stable range of the hydrate on a plane. When determining the lower boundary of the hydrate stability zone, given the seabed temperature and water depth, the temperature is usually extrapolated using the geothermal gradient and then compared with the hydrate stability phase diagram to determine the lower boundary of the hydrate stability zone.

[0027] Figure 1 This is a structural diagram of a temperature and pressure measuring instrument in related technologies, such as... Figure 1 As shown, the instrument includes a flow deflector 1, a variable-weight counterweight 2, a sealed electronic chamber 3, a variable-length extension rod 4, and a needle-shaped temperature and pressure probe 5. These components are connected sequentially from top to bottom. The flow deflector 1 connects to the load-bearing head of a winch located on the sea surface. The sealed electronic chamber 3 houses an inclinometer, accelerometer, communication module, data acquisition module, and power supply. The data acquisition module transmits data from the inclinometer, accelerometer, and temperature and pressure probe to the data processing equipment on the winch via the communication module. The extension rod is used to partially or completely penetrate the seabed sediment. However, the aforementioned measuring instrument uses a pressure sensor to measure pressure parameters. Due to the complex seabed environment and the fact that pressure sensors typically have only one probe and can only measure absolute pressure, this can lead to significant measurement errors.

[0028] To address the above problems, embodiments of the present invention provide a monitoring instrument. Figure 2 This is a schematic diagram of the structure of a monitoring instrument provided in an embodiment of the present invention, as shown below. Figure 2As shown, the monitoring instrument includes an outer probe 110, a pressure chamber 120, a partition 130, a differential pressure sensor 140, and a temperature sensor 150. The partition 130 is disposed inside the outer probe 110, dividing the internal cavity of the outer probe 110 into a first cavity and a second cavity. The outer probe 110 is used to insert into seabed sediments. The pressure chamber 120 is disposed on top of the outer probe 110, and a circuit board is disposed inside the pressure chamber 120. The differential pressure sensor 140 is disposed in the first cavity and connected to the circuit board, and the temperature sensor 150 is disposed in the second cavity and connected to the circuit board. The differential pressure sensor 140 is used to output a differential pressure signal, and the temperature sensor 150 is used to output a temperature signal. The circuit board is used to monitor the seabed sediments based on the differential pressure signal and the temperature signal.

[0029] In this embodiment, the outer probe 110 is a measuring tool. The length of the probe can be set according to actual needs. The outer probe 110 can be made of corrosion-resistant metals such as stainless steel. The pressure chamber 120 refers to equipment capable of withstanding huge water pressure, which can protect the internal structure from the influence of water pressure. The partition 130 is a component that divides the internal cavity of the outer probe 110 into a first cavity and a second cavity. The differential pressure sensor 140 is a sensor used to measure the difference between two pressures and directly outputs a differential pressure signal. The temperature sensor 150 is a sensor that can sense temperature and convert it into a usable output signal.

[0030] In this embodiment, after the external probe 110 of the monitoring instrument is inserted into the seabed sediment, the differential pressure sensor 140 transmits the output differential pressure signal to the circuit board, and the temperature sensor 150 transmits the output temperature signal to the circuit board. The circuit board monitors the temperature and differential pressure of the seabed sediment based on the differential pressure signal and the temperature signal. The differential pressure signal refers to the difference between the pore water pressure of the measured sediment and the hydrostatic pressure of the seabed.

[0031] This embodiment provides a monitoring instrument, including an outer probe, a pressure chamber, a partition, a differential pressure sensor, and a temperature sensor. The partition is disposed inside the outer probe, dividing its internal cavity into a first cavity and a second cavity. The outer probe is used to insert into seabed sediment. The pressure chamber is located at the top of the outer probe, and a circuit board is disposed inside the pressure chamber. The differential pressure sensor is disposed in the first cavity and connected to the circuit board, and the temperature sensor is disposed in the second cavity and connected to the circuit board. The differential pressure sensor outputs a differential pressure signal, and the temperature sensor outputs a temperature signal. The circuit board is used to monitor the seabed sediment based on the differential pressure and temperature signals. The differential pressure signal output by the differential pressure sensor refers to the difference between the pore water pressure of the measured sediment and the hydrostatic pressure of the seabed, which can eliminate the influence of seabed currents and tidal changes on pressure, solving the problem of large measurement errors in existing instruments.

[0032] Based on the above embodiments, Figure 3This is a schematic diagram of another monitoring instrument provided in an embodiment of the present invention, as shown below. Figure 3 As shown, an insulating rod 210 is also provided inside the second cavity, and a temperature sensor 150 includes a thermistor, which is disposed on the insulating rod 210. The monitoring instrument also includes an attitude sensor 280, which is mounted on the top of the insulating rod 210 and is used to measure the attitude of the monitoring instrument.

[0033] In this embodiment, the insulating rod 210 is made of a heat-insulating material, which does not exchange heat with the surrounding environment, thus reducing heat transfer and improving the accuracy of temperature detection. An attitude sensor is a device that measures the attitude and trajectory of an object in space. For example, an attitude sensor may employ an electronic compass or a MEMS (Micro-Electro-Mechanical Systems) accelerometer. Exemplarily, the insulating rod 210 has a groove in which five thermistors are equidistantly installed. The data obtained from the five thermistors and the attitude sensor can be used to calculate the geothermal gradient through univariate linear simulation. The attitude sensor can also be used to correct the geothermal gradient, where the geothermal gradient refers to the rate of increase in the Earth's surface temperature with depth, unaffected by atmospheric temperature, representing a parameter indicating the degree of uneven temperature distribution within the Earth.

[0034] Figure 4 This is a schematic diagram of the circuit board structure provided in an embodiment of the present invention, such as... Figure 4 As shown, the circuit board includes an analog measurement module 310, a main control module 320, and a power supply module 330. The analog measurement module 310 is connected to the differential pressure sensor 140 and the temperature sensor 150. The main control module 320 is connected to the analog measurement module 310. The power supply module 330 is connected to both the main control module 320 and the analog measurement module 310. The analog measurement module 310 is used to convert the differential pressure signal and the temperature signal from analog to digital and output digital signals. The main control module 320 is used to process data based on the digital signals. The power supply module 330 is used to supply power to the analog measurement module 310 and the main control module 320.

[0035] In this embodiment, the analog measurement module 310 is a module that performs high-precision measurement of differential pressure signals and temperature signals and performs analog-to-digital conversion. The main control module 320 is a module that realizes functions such as data collection, data compression, data storage, system control, and upper computer communication interface control. The power supply module 330 can output constant current and voltage and has high stability.

[0036] Specifically, the analog measurement module 310 includes a first bridge circuit 311, a second bridge circuit 312, a first noise reduction matching unit 313, a second noise reduction matching unit 314, a first analog-to-digital converter 315, and a second analog-to-digital converter 316. The first bridge circuit 311, the first noise reduction matching unit 313, and the first analog-to-digital converter 315 are connected in series between the differential pressure sensor 140 and the main control module 320. The second bridge circuit 312, the second noise reduction matching unit 314, and the second analog-to-digital converter 316 are connected in series between the temperature sensor 150 and the main control module 320.

[0037] For example, temperature signal acquisition uses 5 channels, and differential pressure signal acquisition uses 2 channels. The first bridge circuit 311 is a pressure measuring bridge circuit, and the second bridge circuit 312 is a temperature measuring bridge circuit. The core principle of bridge measurement is to use the bridge balance condition to measure the value of unknown resistance, inductance, or capacitance. For example, the second bridge circuit 312 can measure the change in resistance of the thermistor in the temperature sensor with temperature. The first bridge circuit can convert the weak signal output by the differential pressure sensor into a voltage signal, and the second bridge circuit can convert the temperature signal output by the temperature sensor and output an electrical signal. The first and second noise reduction matching units can accurately extract weak signals and have noise suppression and signal matching functions. Both the first and second analog-to-digital conversion units use 24-bit analog-to-digital converters to digitize the electrical signal and transmit the digital signal to the main control module 320. The main control module 320 consists of a microcontroller (MCU), a large-capacity data memory, and a time base circuit. The core component uses a high-performance, multi-channel, low-power MCU, which integrates a high-resolution A / D converter. The high-capacity data storage uses FLASH memory, which is characterized by its small size, large capacity, random access capability, and ability to retain stored data for decades without loss, ensuring stability and reliability. The MCU has an integrated clock function, eliminating the need for an external clock chip. It features multiple alarm functions, timer functions, clock output functions, and interrupt output functions, enabling it to perform various complex timing services. The MCU is equipped with a hardware watchdog timer, allowing for automatic system reset in the event of a fault.

[0038] Continue to refer to Figure 4 The power module 330 includes a charge / discharge control unit 331, a lithium battery 332, and a reference voltage output unit 333. The charge / discharge control unit 331 is connected between the lithium battery 332 and the reference voltage output unit 333. The reference voltage output unit 333 is connected to the analog measurement module 310. The charge / discharge control unit 331 is used to control the lithium battery 332 to supply power to the reference voltage output unit 333. The reference voltage output unit 333 is used to provide a reference voltage to the analog measurement module 310.

[0039] In this embodiment, the power module 330 is the internal power supply module of the monitor. The monitor can be powered by either external or internal power. External power supply refers to the external power supply module supplying power to the monitor via cables, and the external power supply module supplies power to the analog measurement module through the reference voltage output unit. When the external power supply is disconnected, the lithium battery 332 provides power to the system in place of the external power supply. The charge / discharge control unit 331 is connected to the lithium battery 332 and can control the charging or discharging state of the lithium battery 332. By setting multiple rechargeable lithium batteries, the system can be provided with a longer power supply duration, overcoming the problem that existing monitors cannot monitor for extended periods. Referring to the above embodiment, due to changes in external temperature and differential pressure, the resistance of the thermistor and the pressure-sensitive element of the differential pressure sensor change. Different resistance values ​​and pressure-sensitive element changes correspond to different voltages. The reference voltage output unit provides a standard corresponding voltage reference for subtle changes in the thermistor resistance and the pressure-sensitive element of the differential pressure sensor, thereby obtaining high-precision, high-resolution temperature and differential pressure data.

[0040] Based on the above embodiments, the main control module 320 can also monitor the power supply voltage and attitude sensor. The attitude sensor uses an electronic compass and a MEMS accelerometer to obtain tilt angle data in three-dimensional space. For example, if the main control module 320 detects that the monitor is upside down or not inserted into the seabed sediment, it will control the temperature sensor and differential pressure sensor to stop working. The main control module 320 records the received temperature signal data, differential pressure signal data, and attitude sensor detection data into the FLASH memory. Without disassembling the pressure chamber, the system can be controlled and communicated externally via the RS232 serial port protocol, including setting internal system parameters and performing timed sampling control of subsystems. Externally, real-time or timed data and monitoring data stored in the Flash memory can be downloaded via the USB protocol, facilitating data retrieval and solving the problem of high operating costs caused by the need for photoelectric composite cables for real-time signal transmission in existing technologies.

[0041] Based on the above embodiments, continue to refer to Figure 3 The monitoring instrument also includes an inlet 220, a permeable mesh (not shown in the figure), a pointed cone 230, a sealed welded pipe (not shown in the figure), a probe retaining ring 240, an anode column 250, a lifting ring 260, and a frame 270. The inlet 220 is located at the top of the first cavity, and the permeable mesh is located on the outer wall of the first cavity. The pointed cone is located at the bottom of the outer probe 110 and is used to guide the insertion into the seabed sediment. The sealed welded pipe is used to connect the outer probe 110 and the pressure chamber 120. The probe retaining ring 240 is fixed to the outer probe 110, and the anode column 250 is located on the upper surface of the pressure chamber 120. The lifting ring 260 is fixed to the frame 270 and then installed on the pressure chamber.

[0042] In this embodiment, two differential pressure sensors are installed in the middle and bottom of the differential pressure measurement area (i.e., the first cavity). One side of the differential pressure sensor is at the permeable mesh of the outer probe rod, and the other side is at the partition. Correspondingly, two permeable meshes are provided on the outer wall of the first cavity. The differential pressure sensors detect the difference between the pore water pressure of the seabed sediment (flowing in through the permeable mesh) and the seabed hydrostatic pressure (flowing in through the inlet 220). This embodiment uses differential pressure sensors to measure the pressure change pattern of the cold seep activity area. Compared with the pressure sensors in the prior art, it can eliminate the errors caused by swells and tides, making the measurement data more accurate. The pointed cone 230 can guide the insertion into the seabed sediment, and can be inserted into the preset position more accurately than the prior art, solving the problem that the prior art cannot accurately insert into the designed position. The probe rod retaining ring 240 can be fixed to the outer probe rod with screws to ensure that the probe rod is inserted to the appropriate depth. Three sacrificial anodes are added to the pressure chamber. Since the equipment works on the seabed for a long time, seawater corrosion will preferentially corrode the sacrificial anodes, which can prevent the equipment from being corroded by seawater. In this embodiment, the monitoring device can be placed on the seabed by an ROV (Remote-Operated Vehicle) manipulator (the ROV manipulator is connected to the lifting ring). Compared with the prior art, the monitoring device provided in this embodiment is smaller in size and lower in cost. The ROV manipulator can deploy multiple monitoring devices to achieve network monitoring, which solves the problems of large size and weight of monitoring devices, inconvenient deck release operation, and inability to achieve network monitoring when deploying a single device with a cable in the prior art.

[0043] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0044] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A monitoring instrument, characterized in that, Includes external probes, pressure chambers, bulkheads, differential pressure sensors, temperature sensors, and attitude sensors; The partition is disposed inside the outer probe rod, and the partition is used to divide the internal cavity of the outer probe rod into a first cavity and a second cavity. The outer probe rod is used to insert into seabed sediments. The pressure chamber is located at the top of the outer probe, and a circuit board is installed inside the pressure chamber. The circuit board is used to monitor the seabed sediments based on differential pressure signals and temperature signals. The differential pressure sensor is disposed in the first cavity and connected to the circuit board, and the temperature sensor is disposed in the second cavity and connected to the circuit board. The differential pressure sensor is used to output a differential pressure signal, and the temperature sensor is used to output a temperature signal. The second cavity is also provided with an insulation rod, and the temperature sensor includes a thermistor, which is disposed on the insulation rod. The insulation rod is made of a material with good thermal insulation properties. The attitude sensor is installed on the top of the insulation rod. The attitude sensor is used to measure the attitude of the monitoring instrument. The temperature data obtained by the thermistor is used to calculate the ground temperature gradient through univariate linear simulation. The attitude sensor is also used to correct the ground temperature gradient. The circuit board includes an analog measurement module, a main control module, and a power supply module. The analog measurement module is connected to the differential pressure sensor and the temperature sensor. The main control module is connected to the analog measurement module. The power supply module is connected to both the main control module and the analog measurement module. The analog measurement module performs analog-to-digital conversion on the differential pressure signal and the temperature signal respectively and outputs digital signals. The main control module performs data processing based on the digital signals. The power supply module provides power to both the analog measurement module and the main control module.

2. The monitoring instrument according to claim 1, characterized in that, The analog measurement module includes a first bridge circuit, a second bridge circuit, a first noise reduction matching unit, a second noise reduction matching unit, a first analog-to-digital conversion unit, and a second analog-to-digital conversion unit. The first bridge circuit, the first noise reduction matching unit, and the first analog-to-digital conversion unit are connected in series between the differential pressure sensor and the main control module. The second bridge circuit, the second noise reduction matching unit, and the second analog-to-digital conversion unit are connected in series between the temperature sensor and the main control module.

3. The monitoring instrument according to claim 1, characterized in that, The power module includes a charge / discharge control unit, a lithium battery, and a reference voltage output unit. The charge / discharge control unit is connected between the lithium battery and the reference voltage output unit. The reference voltage output unit is connected to the analog measurement module. The charge / discharge control unit is used to control the lithium battery to supply power to the reference voltage output unit. The reference voltage output unit is used to provide a reference voltage to the analog measurement module.

4. The monitoring instrument according to claim 1, characterized in that, It also includes a water inlet and a permeable mesh, wherein the water inlet is located at the top of the first cavity and the permeable mesh is located on the outer wall of the first cavity.

5. The monitoring instrument according to claim 1, characterized in that, It also includes a cone, which is disposed at the bottom of the outer probe and is used to guide insertion into the seabed sediment.

6. The monitoring instrument according to claim 1, characterized in that, It also includes a sealed welded pipe for connecting the outer probe and the pressure chamber.

7. The monitoring instrument according to claim 1, characterized in that, It also includes a probe retaining ring and an anode post, the probe retaining ring being fixed to the outer probe, and the anode post being disposed on the upper surface of the pressure chamber.

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