Sediment stratified sampling device and control method

Abstract

The invention provides a sediment stratified sampling device and a control method. The sediment stratified sampling device comprises a shell, a motor, a drill bit and a sample sampling pipe, the motor is arranged on the shell, and an output shaft of the motor penetrates out of the shell in the axial direction of the shell and is connected with the drill bit. The sample sampling tube at least comprises a first sampling tube and a second sampling tube, the first sampling tube and the second sampling tube extend out of the shell for sampling or retract into the shell after sampling is completed, and the end parts of the first sampling tube and the second sampling tube are respectively provided with a first sealing structure; and second sealing structures are arranged on the inner walls of the first sampling tube and the second sampling tube. The self-adaptive adjustment of the rotating speed of the motor and the double sealing of the sampling pipe generate a synergistic effect, so that the sampling efficiency is improved, the sampling quality is ensured, and the self-adaptive adjustment of the rotating speed of the motor can automatically adjust the sampling intensity and the sampling rate according to the difference of sediments.

Description

Technical Field

[0001] The present invention belongs to the technical field of sample sampling, and particularly relates to a device and control method for stratified sampling of sediment. Background Art

[0002] During the long-term operation of reservoirs, lakes, etc., sediment deposition is an important process for the formation of bottom sediment. Sediment, organic matter, and other fine-grained substances are formed during the process of decreasing flow velocity. As the sediment accumulates continuously, its composition, properties, etc. at different water depths will change, which will have a certain impact on aspects such as reservoir storage capacity, water quality, and ecosystem. It is necessary to conduct accurate stratified sampling of reservoir sediment to deeply understand the distribution status and composition characteristics of bottom sediment at different water levels, and thus provide an accurate basis for the effective disposal of reservoir sediment to a certain extent.

[0003] Existing stratified samplers all have the problem of poor sealing of the sampling pipe. During the lifting process of the sampling pipe, poor sealing of the sampling pipe or water pollution causes the sediment to leak out from the sampling pipe, thus affecting the effectiveness of the sampling piece. Moreover, in the case of large differences in sediments such as silt and sand and gravel, because parameters such as the sampling intensity and sampling rate of the sampling piece cannot be adjusted, the situation where the sampling piece cannot be successfully sampled often occurs. Summary of the Invention

[0004] The present invention provides a device and control method for stratified sampling of sediment, which can solve the technical problem of poor sealing of the sampling pipe existing in the existing stratified sampler.

[0005] The present invention provides a device for stratified sampling of sediment, which is characterized by comprising: a housing, a motor, a drill bit, and a sample sampling pipe;

[0006] The motor is arranged on the housing, and the output shaft of the motor passes through the housing along the axial direction of the housing, and the output shaft of the motor is connected to the drill bit;

[0007] The sample sampling pipe at least comprises a first sampling pipe and a second sampling pipe. The first sampling pipe and the second sampling pipe are horizontally and hierarchically arranged in the housing, and the hierarchical spacing between the first sampling pipe and the second sampling pipe is adjustably arranged along the axial direction of the housing; along the radial direction of the housing, the first sampling pipe and the second sampling pipe are telescopically arranged so that the first sampling pipe and the second sampling pipe can extend out of the housing for sampling or retract into the housing after sampling is completed;

[0008] Sample inlets are respectively arranged at one ends of the first sampling pipe and the second sampling pipe, first sealing structures are respectively arranged at the other ends of the first sampling pipe and the second sampling pipe, and second sealing structures are arranged on the inner walls of the first sampling pipe and the second sampling pipe.

[0009] In some embodiments, the first sealing structure is a cover made of shape memory alloy. The cover deforms to seal the corresponding sampling tube, and a solenoid valve is provided at the sample inlet. The solenoid valve and the cover respectively seal both ends of the corresponding sampling tube.

[0010] In some embodiments, the corresponding sampling tube is provided with a pressure balance hole and a pressure sensor, and the cover deforms according to the pressure difference between the inside and outside of the sampling tube.

[0011] In some embodiments, the second sealing structure includes a heating wire and a silica gel diaphragm. The heating wire is arranged on the inner wall of the corresponding sampling tube, and the silica gel diaphragm is adhered to the circumferential direction of the inner wall of the corresponding sampling tube, and the heating wire is buried in the silica gel diaphragm.

[0012] In some embodiments, along the circumferential direction of the corresponding sampling tube, a spiral installation groove is provided on the inner wall of the corresponding sampling tube, and the heating wire is installed in the installation groove.

[0013] In some embodiments, both the first sampling tube and the second sampling tube are of a double-layer tube structure. The first sampling tube and the second sampling tube both include an inner tube and an outer tube, and the inner tube is telescopically arranged relative to the outer tube;

[0014] A tube outlet is provided on the housing, and a third sealing structure is provided at the tube outlet. The third sealing structure includes a sealing ring and a puncture layer. The sealing ring is installed at the tube outlet, and the puncture layer is provided on the inner peripheral wall of the sealing ring; along the radial direction of the housing, the inner tube punctures the puncture layer to take a sample or retracts into the housing after sampling is completed.

[0015] In some embodiments, both the first sampling tube and the second sampling tube are provided with a telescopic assembly. The telescopic assembly includes an axial electric push rod and a radial electric push rod. The axial electric push rod is vertically arranged, one end of the axial electric push rod is connected to the inner wall of the housing, and the other end of the axial electric push rod is connected to the outer tube; the radial electric push rod is horizontally arranged, one end of the radial electric push rod is connected to the inner wall of the housing, and the other end of the radial electric push rod is connected to the inner tube.

[0016] In some embodiments, it further includes a buoyancy chamber and a plurality of inertial measurement units. The buoyancy chamber is arranged at the top of the housing, and along the axial direction of the housing, the plurality of inertial measurement units are arranged at intervals on the inner wall of the housing. When the inertial measurement unit detects that the tilt angle of the housing is greater than the set value, the buoyancy chamber drives the housing to float.

[0017] In some embodiments, it further includes an anchoring assembly. The anchoring assembly includes a counterweight, a fixing frame, and a plurality of fixed telescopic rods and anchor claws. The counterweight is arranged at the bottom of the housing, the fixing frame is arranged on the outer wall of the housing, the plurality of fixed telescopic rods and anchor claws are correspondingly arranged, the fixed end of the fixed telescopic rod is connected to the fixing frame, and the movable end of the fixed telescopic rod is connected to the anchor claw.

[0018] A control method, which is used to control the above sediment stratified sampling device. The sample sampling tube includes a first sampling tube, a second sampling tube and a third sampling tube. The motor has a current detection module and at least three rotational speeds. The control method includes:

[0019] Start the motor. According to the sampling requirements of the sediment, adjust the stratified spacing of the first sampling tube, the second sampling tube and the third sampling tube. The current detection module detects the current of the motor in real time;

[0020] The motor drives the drill bit to sink to the first sampling layer at the first rotational speed. The first sampling tube is located in the first sampling layer, and the first sampling tube extends and retracts to complete the sampling of the first sampling layer;

[0021] When the current detection module detects that the current of the motor is greater than the first current value, the sediment stratified sampling device switches to the silt mode. The motor drives the drill bit to sink to the second sampling layer at the second rotational speed. The second sampling tube is located in the second sampling layer, and the second sampling tube extends and retracts to complete the sampling of the second sampling layer. Among them, the second rotational speed is greater than the first rotational speed;

[0022] When the current detection module detects that the current of the motor is greater than the second current value, the sediment stratified sampling device switches to the sand and gravel mode. The motor drives the drill bit to sink to the third sampling layer at the third rotational speed. The third sampling tube is located in the third sampling layer, and the third sampling tube extends and retracts to complete the sampling of the third sampling layer. Among them, the second current value is greater than the first current value, and the third rotational speed is less than the first rotational speed;

[0023] When the current detection module detects that the current of the motor is less than the third current value within the first time period, the sediment stratified sampling device completes the sampling. Among them, the third current value is less than the first current value.

[0024] The sediment stratified sampling device and the control method provided by the present invention have the following beneficial effects:

[0025] The self - adaptive adjustment of the motor speed and the double - sealing of the sampling tube have a synergistic effect. On the one hand, it improves the sampling efficiency. The motor can convert the rotation speed of the sampling bit by itself according to its current output situation in combination with the pre - programmed geological database. This self - adaptive adjustment enables the bit to drill at an appropriate speed when facing sediments of different hardness and particle sizes, avoiding problems such as damage to the sampling tube or sample disturbance caused by too high a rotation speed, and low drilling efficiency caused by too low a rotation speed, thus improving the overall sampling efficiency. The double - sealing structure ensures the tightness of the sampling tube. After the sampling tube has completed sampling, the first sealing structure and the second sealing structure can effectively prevent the sediment from leaking out of the sampling tube, enabling the sampling tube to quickly and accurately collect the required samples, reducing the need for repeated sampling due to sample leakage, and further shortening the sampling time. On the other hand, it ensures the sampling quality. The self - adaptive adjustment of the motor speed can automatically adjust the sampling intensity and sampling rate according to the differences in sediments. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only exemplary, and for those of ordinary skill in the art, without creative efforts, other implementation drawings can be obtained based on the provided drawings.

[0027] Figure 1 Schematic diagram of the sampling device according to the embodiment of the present invention;

[0028] Figure 2 Another schematic diagram of the sampling device according to the embodiment of the present invention;

[0029] Figure 3 Schematic diagram of the inner tube and the outer tube according to the embodiment of the present invention;

[0030] Figure 4 Schematic diagram of the first sealing structure and the second sealing structure according to the embodiment of the present invention.

[0031] DRAWINGS: 1 - housing; 101 - tube outlet; 2 - motor; 3 - bit; 4 - first sampling tube; 5 - second sampling tube; 6 - first sealing structure; 601 - sample inlet; 7 - second sealing structure; 701 - heating wire; 702 - silica gel diaphragm; 81 - inner tube; 82 - outer tube; 801 - pressure balance hole; 9 - third sealing structure; 901 - sealing ring; 902 - puncture layer; 10 - axial electric push rod; 11 - radial electric push rod; 12 - buoyancy chamber; 13 - solenoid valve. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually illustrative only and in no way limits the present invention and its application or use. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0033] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom", etc. is usually based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description. Without contrary description, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, it should not be construed as limiting the protection scope of the present invention; the orientation words "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0034] For the convenience of description, spatial relative terms such as "above...", "over...", "on the upper surface of...", "above" etc. can be used here to describe the spatial positional relationship of a device or feature shown in the drawings with other devices or features. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation described in the drawings of the device. For example, if the device in the drawing is inverted, the device described as "above other devices or structures" or "over other devices or structures" will then be positioned "below other devices or structures" or "under other devices or structures". Thus, the exemplary term "above..." can include both the orientation of "above..." and "below...". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the corresponding explanations are made for the spatial relative descriptions used here.

[0035] In addition, it should be noted that the use of words such as "first", "second", etc. to limit components is only for the convenience of distinguishing the corresponding components. Without additional statements, the above words have no special meanings. Therefore, it should not be construed as limiting the protection scope of the present invention.

[0036] Refer to in combination Figure 1As shown in the figure, according to an embodiment of the present invention, a device for stratified sampling of sediment is provided, which includes a housing 1, a motor 2, a drill bit 3 and a sample sampling tube; the motor 2 is arranged on the housing 1, and the output shaft of the motor 2 passes through the housing 1 along the axial direction of the housing 1, and the output shaft of the motor 2 is connected to the drill bit 3; the sample sampling tube at least includes a first sampling tube 4 and a second sampling tube 5, the first sampling tube 4 and the second sampling tube 5 are horizontally arranged in layers in the housing 1, and along the axial direction of the housing 1, the layer spacing between the first sampling tube 4 and the second sampling tube 5 is adjustable; along the radial direction of the housing 1, the first sampling tube 4 and the second sampling tube 5 are telescopically arranged so that the first sampling tube 4 and the second sampling tube 5 can extend out of the housing 1 for sampling or be retracted into the housing 1 after sampling is completed; one ends of the first sampling tube 4 and the second sampling tube 5 are respectively provided with sample inlets 601, the other ends of the first sampling tube 4 and the second sampling tube 5 are respectively provided with first sealing structures 6, and second sealing structures are arranged on the inner walls of the first sampling tube 4 and the second sampling tube 5.

[0037] Specifically, during the process of drilling into the sediment, according to the preset sampling requirements, the sampling device adjusts the layer distance between the first sampling tube 4 and the second sampling tube 5 along the axial direction of the housing 1, starts the motor 2, and places the sampling device into the sediment. The output shaft of the motor 2 drives the drill bit 3 to rotate and drill into the sediment. During this process, the motor 2 combines the output situation of its current with the pre-compiled geological database, and the motor 2 can automatically convert the rotation speed of the sampling drill bit 3; according to different depths drilled, when the first sampling tube 4 is located in a sediment layer, the first sampling tube 4 extends out of the housing 1, and the sample enters the tube of the first sampling tube 4 from the sample inlet 601. When the sample in the first sampling tube 4 reaches the set sampling amount, the sample inlet 601 is sealed, the first sealing structure 6 seals the other end of the first sampling tube 4, and the second sealing structure 7 forms a sealing layer on the inner wall of the first sampling tube 4. The first sealing structure 6 and the second sealing structure 7 are used in cooperation to wrap the sample. After sampling is completed, the first sampling tube 4 is retracted into the housing 1. When the second sampling tube 5 is located in another sediment layer at a different depth, the second sampling tube 5 performs the above sampling steps in the same way. After sampling is completed, the second sampling tube 5 is retracted into the housing 1, that is, the first sampling tube 4 and the second sampling tube 5 work sequentially. In other embodiments, according to the sampling requirements, the first sampling tube 4 and the second sampling tube 5 can also sample simultaneously.

[0038] It should be noted that the drive of the motor 2 and the adjustment of the two sampling tubes in the radial and axial directions are realized through different drive systems respectively, and the two are synchronized, so as to realize the stratified sampling of the sediment.

[0039] In this embodiment, it is applicable to stratified sampling of reservoir sediments. Since there are different sediment layers at different depths of the sediments, the physical parameters such as the viscosity of the sediments will also be different. Especially in the case of large differences in sediments such as silt and gravel, parameters such as the sampling intensity and sampling rate of the sampling device for the sample piece will also be different. Different geological databases are pre-compiled before the sampling device samples. The motor 2 can know the change in the resistance encountered during sampling according to the speed of the current output by it, and judge and feedback the sampling force based on the pre-compiled geological database, so as to achieve the adjustment in different resistance situations during sampling and realize adaptive sampling.

[0040] In this embodiment, both the first sampling tube 4 and the second sampling tube 5 can move in the radial and axial directions of the outer shell 1 to achieve the adjustment of the stratified spacing and telescopic sampling. Since stratified sampling is to be achieved, after sampling is completed, in order to avoid sample mixing, a first sealing structure 6 and a second sealing structure 7 are provided on each sampling tube in this embodiment. The first sealing structure 6 is for the sealing of the tube end, and is isolated from the external environment through physical isolation to prevent the sample from being washed away by the water flow when the sampling tube is lifted and the pollutants in the adjacent sediment layer from infiltrating back into the sampled sample in the reverse direction. The second sealing structure 7 is to seal the sample and the tube wall. The first sealing structure 6 and the second sealing structure 7 are used in cooperation. The tube end seal "locks" external intrusion, and the inner wall seal "suppresses" internal disturbance. The two respectively block the external path and the internal path of sample leakage, forming a dead-end protection. In addition, if the first sealing structure 6 fails to close completely due to foreign object jamming, the second sealing structure 7 can still block most of the sample leakage through the inner wall diaphragm; conversely, if the inner wall seal fails due to wear, the tube end seal can still complete the basic seal independently. In continuous multi-layer sampling, the double seal can alternately assume the main seal responsibility, reducing the risk of overall failure caused by the fatigue of a single structure. The double seal constitutes a "main-backup" or "parallel" redundant system, significantly reducing the probability of sampling failure caused by a single-point failure.

[0041] In this embodiment, the speed adaptive adjustment of the motor 2 and the double sealing of the sampling tube produce a synergistic effect. On the one hand, the sampling efficiency is improved. The motor 2 can combine its current output situation with the pre-compiled geological database to automatically convert the rotation speed of the sampling bit 3. This adaptive adjustment enables the bit 3 to drill at an appropriate speed when facing sediments with different hardness and particle sizes, avoiding problems such as damage to the sampling tube or sample disturbance caused by too high a rotation speed, and low drilling efficiency caused by too low a rotation speed, thus improving the overall sampling efficiency. The double-sealing structure ensures the sealing performance of the sampling tube. After the sampling tube completes sampling, the first sealing structure 6 and the second sealing structure 7 can effectively prevent the silt from leaking out of the sampling tube, enabling the sampling tube to quickly and accurately collect the required samples, reducing the need for repeated sampling due to sample leakage, and further shortening the sampling time. On the other hand, the sampling quality is guaranteed. The speed adaptive adjustment of the motor 2 can automatically adjust the sampling intensity and sampling rate according to the differences in sediments. For example, when encountering a harder sand and gravel sediment layer, the motor 2 can reduce the speed to avoid damage to the sampling tube due to too high a rotation speed; when encountering a softer silt layer, the motor 2 can appropriately increase the speed to accelerate the sampling speed. This flexibility enables the sampling device to better adapt to the characteristics of different sediments, thus ensuring that high-quality samples can be successfully collected in various situations. The double-sealing structure plays an important role during sampling. The first sealing structure 6 seals the end of the sampling tube, and the second sealing structure 7 forms a sealing layer on the inner wall of the sampling tube. This not only prevents the sample from being contaminated by mixing with the external water body during sampling, but also avoids sample leakage due to changes in water pressure during the lifting process, ensuring the integrity and representativeness of the sample. Using the sampling device of this embodiment can effectively overcome problems such as interlayer pollution during stratified sampling, poor adaptability of the sampler, and inaccurate positioning in the prior art, achieve precise sampling of reservoir sediments, meet the sampling and analysis requirements for the reservoir sediments in the engineering field, and realize a dedicated, efficient, and reliable tool for the research on the reservoir sediments in the water conservancy engineering field.

[0042] As a specific implementation, the motor 2 is arranged at the central position of the device, on top of the sampling tube. The motor 2 is integrally connected to the outer shell 1 of the device through a fixed bracket to ensure its stability during operation. The output shaft of the motor 2 is connected to the spiral drill bit 3 through a coupling to directly drive the rotation of the drill bit 3. The motor 2 selects an IP68 waterproof brushless motor 2 (rated torque 2 N·m), which drives the spiral drill bit 3 (diameter 50 mm, pitch 30 mm) through a harmonic reducer (reduction ratio 1:50), providing continuous and controllable power to drill into sediments under different geological conditions. It has the advantages of high efficiency, energy saving, low noise, and long life, and can work continuously and stably in complex underwater environments. The harmonic reducer has a high reduction ratio, which can convert the high-speed rotation of the motor 2 into the low-speed and high-torque output of the spiral drill bit 3 to meet the drilling and sampling capabilities in different hard sediments. Moreover, the speed and torque of the motor 2 can be automatically adjusted according to the resistance encountered during the sampling process to achieve adaptive sampling. The drill bit 3 has a diameter of 50 mm and is equipped with tungsten carbide cutting teeth, which have strong cutting ability and can smoothly drill into various sediments. The high hardness and high wear resistance of the tungsten carbide cutting teeth play an efficient drilling role in drilling in different strata.

[0043] Refer to in combination Figures 1 to 4 As shown, the first sealing structure 6 is a cover. The material of the cover is a shape memory alloy, specifically nickel-titanium alloy, with a thickness of 1.2 mm, a contact pressure of 0.6 MPa after closing, a phase change point of 35 °C for the shape memory alloy. It deforms and closes when encountering water due to temperature difference changes, and the closing force ≥ 50 N. The cover deforms to seal the corresponding sampling tube. The sample inlet 601 is provided with a solenoid valve 13, and the solenoid valve 13 and the cover respectively seal both ends of the corresponding sampling tube.

[0044] In this embodiment, the first sampling tube 4 or the second sampling tube 5 extends out of the outer shell 1 for sampling. When the sample in the tube reaches the set sampling volume, the solenoid valve 13 closes the sample inlet 601. The pressure in the sampling tube rapidly drops below 70% of the outer water pressure, resulting in a change in the temperature inside the tube. The shape memory alloy cover deforms under the action of the temperature difference, triggering the deformation and closing of the shape memory alloy cover, automatically closing the cover to form a sealed chamber. The sampling tube is retracted into the outer shell 1 to restore the initial state, completing the sampling of one layer of sediment.

[0045] It should be noted that the closing of the cover has nothing to do with whether the sample contacts the cover, but is triggered by the pressure change in the sampling tube.

[0046] In this embodiment, the shape memory alloy cover automatically closes under the action of temperature change. This adaptive characteristic makes the sealing process more reliable, ensuring the sealing effect even in a complex underwater environment. The solenoid valve 13 is used in cooperation with the shape memory alloy cover, making the sealing reliability of the sampling tube high. Since the sampling tube in this embodiment needs to automatically sample throughout the process, the solenoid valve 13 automatically closes the sample inlet 601. With the temperature change, it triggers the closing of the shape memory alloy cover. The whole process requires no manual intervention and is fully automated, improving the efficiency and accuracy of sampling. The automated design reduces the complexity of human operation and the possibility of errors. Especially in a complex underwater environment, this automated characteristic is particularly important. In addition, the closing of the shape memory alloy cover is based on temperature change. This characteristic enables the device to adapt to the sampling requirements under different water temperature conditions. Even in an environment with a large temperature change, the cover can close reliably to ensure the sealing effect. Moreover, the combined design of the solenoid valve 13 and the shape memory alloy cover can adapt to the characteristics of different sediments. For example, when collecting softer silt, the solenoid valve 13 can quickly close to prevent excessive entry of the sample, while when collecting harder sand and gravel, the closing of the shape memory alloy cover can also ensure the tightness of the sample.

[0047] Referring to Figures 1 to 4 As shown, the corresponding sampling tube is provided with a pressure balance hole 801 and a pressure sensor. The cover deforms according to the pressure difference between the inside and outside of the sampling tube. The aperture of the pressure balance hole 801 is 0.5 mm and it is formed by drilling at an inclination of 45°.

[0048] Specifically, the solenoid valve 13 of each layer of the sampling tube is a micro solenoid valve 13 (response time < 0.1 s). After the pressure sensor (range 0 - 50 kPa) detects that the pressure inside the tube rapidly drops to 70% of the outer water pressure, it can quickly close the valve of the current layer and open the sampling tube of the lower layer to ensure that the samples of different layers are separated and do not mix. The characteristic of the rapid response of the micro solenoid valve 13 timely disconnects the correlation between the sample and the outside world, cutting off the possibility of sample mixing caused by pressure change; the rapid and accurate measurement of the pressure sensor can provide a data basis for layer-by-layer isolation of the samples. When the sample enters the tube, the pressure balance hole 801 can discharge the air inside the tube. The pressure sensor monitors the pressure difference between the inside and outside of the sampling tube in real time, providing an accurate control basis for the deformation of the cover. The preferred method is that the pressure sensor can monitor the pressure difference between the inside and outside of the sampling tube in real time and feedback the data to the control system. These data can be used to further optimize the sampling strategy. Moreover, according to the data of the pressure sensor, the control system can intelligently adjust the sampling parameters (such as sampling volume, sampling depth, etc.) to adapt to different sampling environments and requirements.

[0049] In this embodiment, the pressure balance hole 801 allows the water pressure inside and outside the sampling tube to be balanced to a certain extent, thereby reducing the risk of cap damage caused by excessive pressure difference, which is particularly important in an underwater high-pressure environment because an excessive pressure difference may cause the cap to fail to close properly or even rupture. Through the pressure balance hole 801, the pressure difference between the inside and outside of the sampling tube can be controlled, thereby reducing the possibility of the sampling tube being deformed or damaged due to excessive pressure difference and extending the service life of the device. The setting of the pressure balance hole 801 and the pressure sensor enables the device to adapt to the sampling requirements at different water depths. In a deep-water environment, the pressure difference is large, and the pressure balance hole 801 can partially balance the pressure difference to ensure that the cap can work properly. Moreover, different sediment characteristics (such as hardness, particle size, etc.) will cause different pressure changes. Through the real-time monitoring of the pressure sensor and the adjustment of the pressure balance hole 801, the device can better adapt to these changes and ensure the smooth progress of the sampling process.

[0050] Referring to Figures 1 to 4 As shown, the second sealing structure 7 includes a heating wire 701 and a silica gel diaphragm 702. The heating wire 701 is arranged on the inner wall of the corresponding sampling tube, and the silica gel diaphragm 702 is adhered to the circumferential direction of the inner wall of the corresponding sampling tube, and the heating wire 701 is buried in the silica gel diaphragm 702.

[0051] Specifically, when the sample enters the tube, the pressure balance hole 801 can discharge the air in the tube, and the pressure sensor monitors the pressure difference between the inside and outside of the sampling tube in real time. When the pressure inside the sampling tube rapidly drops below 70% of the outer water pressure, the deformation and closing of the shape memory alloy cap are triggered. At this time, the sampling tube has completed sampling. To further improve the sealing performance, the heating wire 701 (with a power of 5W) is started. Since the heating wire 701 is buried in the silica gel diaphragm 702, that is, the heating wire 701 is in full contact with the silica gel diaphragm 702, the heating wire 701 can heat the silica gel diaphragm 702 to uniformly melt it. The melted silica gel is liquid silica gel, which forms a continuous sealing layer on the inner wall of the sampling tube. Due to the fluidity and adhesiveness of the silica gel, this sealing layer can closely adhere to the inner wall of the sampling tube to form a sealed chamber, ensuring the isolation between each layer of samples.

[0052] In this embodiment, compared with heating the edge of the silica gel diaphragm 702, which causes local overheating of the silica gel diaphragm 702 (the edge melts quickly) while the central region is not fully melted, forming an incomplete sealing layer, in this embodiment, the heating wire 701 is embedded in the silica gel diaphragm 702, so that the silica gel diaphragm 702 can be in full contact with the heating wire, and the heating wire 701 can heat the silica gel diaphragm 702 more evenly. The heating wire 701 and the silica gel diaphragm 702 are set as the second sealing structure 7. The activation of the heating wire 701 is automatically triggered. After the sampling tube completes sampling, the heating wire 701 automatically heats the silica gel diaphragm 702 to melt it and form a sealing layer. This automated design reduces the complexity of manual operation and the possibility of errors, improving the efficiency and reliability of sampling. The sealing layer formed by the silica gel diaphragm 702 can effectively prevent external water from entering the sampling tube and avoid sample contamination, which is particularly important for samples that require precise analysis, ensuring the originality and representativeness of the samples. On the basis of the closure of the shape memory alloy cap, the combination of the heating wire 701 and the silica gel diaphragm 702 further enhances the sealing performance. During the layered sampling process, this sealing structure can ensure the isolation between samples of each layer and prevent the mixing of samples at different depths, thereby improving the accuracy of sampling data. In addition, the melting temperature of the silica gel diaphragm 702 can be adjusted according to the actual water temperature conditions, enabling the device to complete sealing reliably in different water temperature environments. This adaptability allows the device to be applicable to a wider range of sampling environments. Whether it is soft silt or hard sand and gravel, the combination of the heating wire 701 and the silica gel diaphragm 702 can effectively seal the sampling tube to ensure the integrity and sealing of the samples.

[0053] As a specific implementation manner, the combined design of the heating wire 701 and the silica gel diaphragm 702 can be adjusted according to different sampling requirements, such as adjusting the sampling volume, sampling depth, etc., with high flexibility. This sealing method can also be easily extended to more sampling tubes to meet more complex sampling requirements, such as simultaneously collecting sediment samples at multiple different depths.

[0054] Combined with reference to Figures 1 to 4 As shown, along the circumferential direction of the corresponding sampling tube, spiral mounting grooves are provided on the inner wall of the corresponding sampling tube, and the heating wire 701 is installed in the mounting grooves.

[0055] In this embodiment, the spiral installation groove can increase the distribution length of the heating wire 701 on the inner wall of the sampling tube, thereby increasing the heating area. The spiral installation groove makes the contact between the heating wire 701 and the silica gel diaphragm 702 closer, improving the energy transfer efficiency. This enables the silica gel diaphragm 702 to be heated more evenly, accelerating the fusing process and enhancing the heating efficiency. The spirally distributed heating wire 701 can ensure that the silica gel diaphragm 702 is evenly heated in the circumferential direction, avoiding local overheating or uneven heating, thus improving the sealing quality. The spiral installation groove provides a stable installation position for the heating wire 701, preventing the heating wire 701 from shifting or loosening during use. This fixing method ensures the reliability of the heating wire 701 during long-term use. The spiral structure can reduce the displacement of the heating wire 701 in the sampling tube due to vibration or water flow impact, improving the stability of the device. In addition, the spirally distributed heating wire 701 can ensure that the silica gel diaphragm 702 is evenly fused in the circumferential direction, forming a continuous sealing layer. This uniform fusing helps to improve the integrity and sealing effect of the sealing layer. Uniform heating can reduce the bubbles and voids generated during the silica gel fusing process, ensuring the density of the sealing layer and further improving the sealing quality. Moreover, the spiral installation groove can be adjusted according to the inner diameter of the sampling tube, adapting to sampling tubes of different sizes, with high flexibility. The spirally distributed heating wire 701 can adjust the density and distribution of the heating wire 701 according to the sampling requirements to meet different heating and sealing requirements.

[0056] As a specific implementation manner, both the silica gel diaphragm 702 and the heating wire 701 adopt a thin design. The silica gel diaphragm 702 is made of a flexible material with a thickness within 2 mm, which can maintain its shape and function during the telescopic process of the sampling tube and will not break or deform due to the movement of the sampling tube, ensuring that it will not hinder the telescopic movement of the sampling tube and the entry of the sample during the sampling process. At the same time, the silica gel material has good chemical stability and water resistance, and can maintain its sealing performance for a long time to ensure the integrity of the sample during collection, storage, and transportation.

[0057] In this embodiment, considering that whether it is the adjustment of the layer spacing or the telescopic sampling of the first sampling tube 4 and the second sampling tube 5, the tube body moves in two directions of the outer shell 1. Both the first sampling tube 4 and the second sampling tube 5 are of a double-layer tube structure. Both the first sampling tube 4 and the second sampling tube 5 include an inner tube 81 and an outer tube 82, and the inner tube 81 is telescopically arranged relative to the outer tube 82; a tube outlet 101 is provided on the outer shell 1, and a third sealing structure 9 is provided at the tube outlet 101. The third sealing structure 9 includes a sealing ring 901 and a puncture layer 902. The sealing ring 901 is installed at the tube outlet 101, and a puncture layer 902 is provided on the inner peripheral wall of the sealing ring 901. The puncture layer 902 is a relatively thin flexible layer; along the radial direction of the outer shell 1, the inner tube 81 punctures the puncture layer 902 for sampling or retracts into the outer shell 1 after sampling is completed.

[0058] Specifically, when it is necessary to adjust the stratification spacing between the first sampling tube 4 and the second sampling tube 5, it is essentially to adjust the position of the outer tube 82 in the axial direction of the housing 1. When the first sampling tube 4 and the second sampling tube 5 need to expand and contract for sampling, the inner tube 81 is essentially displaced in the radial direction of the housing 1. A sample inlet 61 is provided on the inner tube 81, and the solenoid valve 13 is arranged at the sample inlet 61. A first sealing structure 6 is arranged at one end of the inner tube 81 away from the sample inlet 61, and the outer tube 82 is an open structure. The inner tube 81 can extend out of the outer tube 82. Along the radial direction of the inner tube 81, the pressure balance hole 801 penetrates through the inner tube 81 and the outer tube 82, so that the air in the inner tube 81 can be discharged. When the inner tube 81 extends out, the inner tube 81 will pierce through the puncture layer 902, and the inner tube 81 extends out of the housing 1. When the sampling is completed, the inner tube 81 is then retracted into the housing 1, that is, retracted into the outer tube 82. It should be noted that since the solenoid valve 13 is arranged on the inner tube 81 in this embodiment, when the inner tube 81 is retracted, the inner tube 81 is not completely retracted into the outer tube 82. Moreover, when the nozzle of the outer tube 82 contacts the outer wall of the solenoid valve 13, the inner tube 81 will no longer retract. The sample itself is stored in the inner tube 81, and the gap between the inner tube 81 and the outer tube 82 is very small, which will not affect the sealing performance.

[0059] In this embodiment, the inner tube 81 can expand and contract in the radial direction of the housing 1, so that the sampling tube can extend out of the housing 1 for sampling as needed, or be retracted into the interior of the housing 1 after the sampling is completed, reducing the volume of the device in the non-sampling state and improving the flexibility of the device. The outer tube 82 provides protection for the inner tube 81, reducing the risk of the inner tube 81 being damaged by the outside world in the non-working state. When the inner tube 81 is retracted into the outer tube 82, the outer tube 82 can effectively prevent the inner tube 81 from being scratched or damaged by sediments or other external objects. The sealing ring 901 is installed at the tube outlet 101, which can effectively prevent water from entering the interior of the housing 1. The puncture layer 902, as a relatively thin flexible layer, can be quickly sealed when the inner tube 81 pierces through, preventing water from entering the inner tube 81 and the outer tube 82 from the puncture point. The design of the puncture layer 902 enables the inner tube 81 to quickly pierce through and extend out of the housing 1 for sampling, and at the same time be quickly sealed after the sampling is completed. The combined design of the sealing ring 901 and the puncture layer 902 ensures that the sample will not be contaminated by the outside water during the sampling process. Combining the puncture layer 902 and the sealing ring 901 provides a double-sealing guarantee. When the inner tube 81 extends out of the housing 1 for sampling, the puncture layer 902 is pierced, and the inner tube 81 can extend out smoothly; when the inner tube 81 is retracted, the puncture layer 902 is automatically sealed to prevent water from entering the interior of the housing 1, ensuring the sealing performance of the device. The combined design of the sealing ring 901 and the puncture layer 902 ensures that the sample will not be contaminated by the outside water during the sampling process, guaranteeing the integrity of the sample.

[0060] In this embodiment, a solenoid valve 13 is provided at the sample inlet 601. A first sealing structure 6 is provided at the end of the sampling tube, a second sealing structure 7 is provided on the inner wall of the sampling tube, and a third sealing structure 9 is provided at the tube outlet 101 of the housing 1. The rapid opening and closing of the solenoid valve 13 can quickly control the entry and exit of the sample, reducing the sampling time. The automatic sealing functions of the first sealing structure 6 and the third sealing structure 9 can ensure the tightness of the sample during the sampling process, avoiding sampling failure caused by sample leakage, thereby improving the sampling efficiency. The three sealing structures cooperate with each other to jointly ensure the tightness of the sampling process, reducing the risk of equipment failure caused by sample leakage or external water entry, and improving the reliability and stability of the equipment. Through the synergistic effect of the multi-layer sealing structure, it can effectively prevent the sample from being contaminated or leaking during sampling, storage, and transportation, ensuring the quality and integrity of the sample, and providing accurate data support for subsequent analysis and research. Since the sealing structure can effectively protect the interior of the equipment, reducing the intrusion of water and impurities, the design of the three sealing structures can adapt to different underwater environments and sampling conditions. Whether it is shallow water or deep water, whether it is soft silt or hard sand and gravel, it can ensure the smooth progress of the sampling process, improving the adaptability and versatility of the equipment.

[0061] As a specific implementation manner, the housing 1 adopts a nested structure of a 304 stainless steel outer tube 82 (wall thickness 1.5 mm) and a transparent polycarbonate inner tube 81 (wall thickness 3 mm). Ring-shaped scale lines are engraved on the surface of the inner tube 81 every 10 cm, facilitating depth observation and recording of the sampling position. The 304 stainless steel outer tube 82 has high hardness and stiffness, which can effectively protect the safety of the inner tube 81 and the sample during sampling and transportation. The polycarbonate inner tube 81 is transparent, facilitating direct observation of the sample, and the ring-shaped scale lines on the surface of the inner tube 81 facilitate more accurate recording of the depth value.

[0062] Combined with reference to Figures 1 to 4 As shown in the figure, both the first sampling tube 4 and the second sampling tube 5 are provided with telescopic components. The telescopic components include an axial electric push rod 10 and a radial electric push rod 11. The axial electric push rod 10 is vertically arranged. One end of the axial electric push rod 10 is connected to the inner wall of the housing 1, and the other end of the axial electric push rod 10 is connected to the outer tube 82. The radial electric push rod 11 is horizontally arranged. One end of the radial electric push rod 11 is connected to the inner wall of the housing 1, and the other end of the radial electric push rod 11 is connected to the inner tube 81.

[0063] Specifically, the position adjustment of the inner tube 81 and the outer tube 82 is realized by the radial electric push rod 11 and the axial electric push rod 10 respectively. The elongation or shortening of the axial electric push rod 10 can change the relative position of the appearance in the housing 1, that is, the stratification distance between the first sampling tube 4 and the second sampling tube 5 is realized by adjusting their outer tubes 82. Moreover, the first sampling tube 4 and the second sampling tube 5 perform stratified sampling. By setting the radial electric push rod 11, the inner tubes 81 of the first sampling tube 4 and the second sampling tube 5 can be pushed out or retracted respectively. In this embodiment, the drive of the motor 2 and the drive of the electric push rod work separately. Therefore, even during stratified sampling, each structure can work independently.

[0064] In this embodiment, by adjusting the position of the outer tube 82 through the axial electric push rod 10, the stratification distance between the first sampling tube 4 and the second sampling tube 5 can be accurately controlled to achieve stratified sampling at different depths. At the same time, the radial electric push rod 11 can independently control the telescopic movement of the inner tube 81, enabling each sampling tube to sample at different radial positions. The electric push rod can provide precise position control to ensure that the sampling tube can accurately reach the target position, which is very important for application scenarios that require precise sampling and can improve the accuracy and reliability of sampling. Moreover, the electric push rod supports fine-tuning, and can make fine adjustments to the position of the sampling tube in a complex underwater environment to adapt to different sampling conditions. In addition, the electric push rod supports fine-tuning, and can make fine adjustments to the position of the sampling tube in a complex underwater environment to adapt to different sampling conditions. Combined with sensors and control systems, the electric push rod can automatically adjust its position according to the real-time monitored data to adapt to different sampling requirements and environmental conditions.

[0065] As a specific implementation method, the electric push rod can be equipped with a position sensor to real-time monitor the position of the sampling tube and feedback the data to the control system. These data can be used to further optimize the sampling strategy, improve the accuracy and efficiency of sampling. According to the monitored data, the control system can intelligently adjust the telescopic degree of the electric push rod to adapt to different sampling conditions and improve the sampling success rate.

[0066] As a specific implementation method, the axial electric push rod 10 and the radial electric push rod 11 adopt a nested telescopic mechanism, which is powered by 6 groups of electric push rods (stroke 0 - 80 cm, thrust 200 N). The adjustment range of the distance between adjacent sampling tubes is between 5 - 30 cm, which can conveniently adapt to different sampling positions and depths. The electric push rod can accurately control the telescopic movement of the sampling tube within a predetermined depth value range to finally complete stratified sampling. The nozzle of the inner tube 81 is designed with an inverted conical cutter (cone angle 60°, tungsten carbide coating), which can effectively reduce the insertion resistance and enhance the sampling efficiency. The tungsten carbide coating is hard and wear-resistant, and can better maintain its sharp state during the cutting process, reducing the energy input during the sampling process.

[0067] With reference to Figures 1 to 4 As shown, it further includes a buoyancy chamber 12 and a plurality of inertial measurement units. The buoyancy chamber 12 is arranged at the top of the outer shell 1. Along the axial direction of the outer shell 1, the plurality of inertial measurement units are arranged at intervals on the inner wall of the outer shell 1. When the inertial measurement unit detects that the inclination angle of the outer shell 1 is greater than the set value, the buoyancy chamber 12 drives the outer shell 1 to float upward.

[0068] Specifically, existing samplers often have the problem of depth position deviation. Generally, mechanical scales or a single sensor are used, and it is difficult to achieve the accuracy of centimeter-level sampling depth, resulting in a relatively large deviation and poor accuracy. In this embodiment, an inertial measurement unit is provided. After the inertial measurement unit detects that the inclination angle of the sampling device is >15°, the device automatically stops collecting, and the buoyancy chamber 12 automatically floats upward to protect the device, avoiding equipment loss and sample loss caused by accidents. The inertial measurement unit is used to judge the attitude angle of the device, and once an abnormal inclination occurs, automatic protection is realized.

[0069] In this embodiment, the inertial measurement unit monitors the attitude angle of the device in real time to ensure that the device remains stable during the sampling process. A stable device attitude helps to improve the accuracy and success rate of sampling, avoiding sampling failure caused by device inclination. Through the automatic floating protection function, the device can stop sampling and float upward in time when an abnormal inclination occurs, reducing sampling interruption caused by device damage or loss and improving sampling efficiency. The sampling device samples in a stable state, which can ensure the accuracy of the collected samples and data. If the device inclines during the sampling process, it may cause sample leakage or data deviation, while the coordinated action of the inertial measurement unit and the buoyancy chamber 12 can avoid this situation. By floating upward in time to protect the device, the risk of data loss caused by device damage or loss is reduced, ensuring the integrity of the sampling data.

[0070] As a specific implementation manner, the buoyancy chamber 12 (with a volume of 5L and an airbag inflation pressure of 0.8 MPa) is used to provide the upward floating power for the instrument after sampling and is easy to recover. The buoyancy chamber 12 is designed to enable the device to automatically float to the water surface after sampling is completed, facilitating recovery by the operator.

[0071] With reference to Figures 1 to 4 As shown, it further includes an anchoring assembly. The anchoring assembly includes a counterweight, a fixing frame, and a plurality of fixed telescopic rods and anchor claws. The counterweight is arranged at the bottom of the outer shell 1, the fixing frame is arranged on the outer wall of the outer shell 1, the plurality of fixed telescopic rods and anchor claws are arranged correspondingly, the fixed end of the fixed telescopic rod is connected to the fixing frame, and the movable end of the fixed telescopic rod is connected to the anchor claw.

[0072] Specifically, the counterweight is arranged at the bottom of the device, at the lower end of the outer shell 1, to ensure its stability during operation. The fixed telescopic rod is arranged in the middle of the device, on the outside of the outer shell 1. The fixed telescopic rod is connected to the outer shell 1 through a fixed bracket to ensure its stability during operation. The movable end of the fixed telescopic rod is connected to the anchor claw for driving the expansion and contraction of the anchor claw. The anchor claw is arranged at the bottom of the device, below the counterweight. The anchor claw is connected to the telescopic rod through a movable joint to ensure its flexible expansion and contraction during operation. After starting the sampling device, the counterweight increases the overall weight of the device, enabling the device to sink steadily to the set sampling depth. Then start the fixed telescopic rod to drive the anchor claw to extend and insert it into the sediment to fix the attitude of the device. After the device is stably fixed at the set sampling position, start the sampling process to complete the stratified sampling at different depths. After sampling is completed, start the telescopic rod to retract the anchor claw, and the counterweight makes the device float to the water surface to complete the sampling process.

[0073] In this embodiment, the main function of the counterweight is to increase the overall weight of the device, enabling the device to sink steadily to the set sampling depth. The weight of the counterweight is designed according to the requirements of the overall weight of the device and the sampling depth to ensure that the device can sink stably and maintain a vertical attitude during the sampling process. The main function of the telescopic rod is to drive the expansion and contraction of the anchor claw to ensure that the device can be stably fixed at the set sampling position during the sampling process. The length of the telescopic rod is designed according to the requirements of the sampling depth to ensure that the anchor claw can effectively insert into the sediment and fix the attitude of the device. The main function of the anchor claw is to insert into the sediment and fix the attitude of the device to prevent the device from shifting or tilting during the sampling process. The shape and size of the anchor claw are designed according to the properties of the sediment to ensure that it can effectively insert into the sediment and fix the attitude of the sampling device.

[0074] As a specific implementation method, for the sampling device in this embodiment to achieve automatic sampling, each component needs to cooperate with each other. The hardware architecture of this embodiment is provided with a main controller, and a high-performance STM C32H743VI (with 2 ARM Cortex M7 cores and a working frequency of 200 MHz) is selected to achieve good data processing and control. The main controller receives and quickly processes various sensor measurement data and performs real-time control based on the pre-set control logic. Underwater communication uses a 2.4 GHz acoustic modem (maximum rate 5 kbps, effective transmission distance 500 m) to communicate with the above-water control terminal in real time for underwater operation and communication. The acoustic modem can communicate stably in a complex underwater environment and helps the operator obtain the working status information of the sampling device on the shore or on the ship, so as to perform remote operation.

[0075] The module connection relationship and key parameters are as follows: Main control CPU: STM32H743VI → CAN bus → Motor 2 drive module (model DRV8323), which can achieve precise control of Motor 2, control the sampling speed and sampling intensity, and ensure the smooth progress of sampling. Sensor input: Pressure sensor (MLX5050DP) → Sampling 12-bit ADC → Central control, which can detect the pressure in the pipe in real time, is used for anti-mixing control, and ensures that the stratified samples do not mix. Communication link: Acoustic modem (model AquaSeNT2000) The underwater control terminal builds a stable communication bridge underwater, realizes telemetry and remote control, and is convenient to use. Control cycle: 100 ms, which ensures that the system can quickly respond to various changes, realizes real-time control, and ensures the accuracy and reliability of the sampling process. Instruction response delay: < 200 ms, which improves the timeliness and accuracy of operations, enhances the user experience, and makes remote operations smoother.

[0076] Refer to in combination Figures 1 to 4 As shown, a control method is used for the above-mentioned sediment stratified sampling device. The sample sampling tube includes a first sampling tube 4, a second sampling tube 5, and a third sampling tube that are stratified. The motor 2 has a current detection module and at least three rotation speeds. The current detection module is integrated in the control circuit of the motor 2 and continuously monitors the working current of the motor 2. The current detection module is connected to the main controller through a cable and transmits the detected current data to the main controller for judging the resistance change during the sampling process. The control method includes:

[0077] According to the sampling requirements of the sediment, adjust the stratified spacing of the first sampling tube 4, the second sampling tube 5, and the third sampling tube;

[0078] Start the motor 2. The current detection module continuously detects the current of the motor 2 at a sampling rate of 1 kHz. The motor 2 drives the drill bit 3 to sink to the first sampling layer at the first rotation speed. The first sampling tube 4 is located in the first sampling layer, and the first sampling tube 4 extends and retracts to complete the sampling of the first sampling layer. The first rotation speed is the initial rotation speed of 200 rpm;

[0079] When the current detection module detects that the current of the motor 2 is greater than the first current value (1.2 A), the sediment stratified sampling device switches to the silt mode. The motor 2 drives the drill bit 3 to sink to the second sampling layer at the second rotation speed (300 rpm). The second sampling tube 5 is located in the second sampling layer, and the second sampling tube 5 extends and retracts to complete the sampling of the second sampling layer. Among them, the second rotation speed (300 rpm) is greater than the first rotation speed (200 rpm);

[0080] When the current detection module detects that the current of the motor 2 is greater than the second current value (2.5A), the sediment layer sampling device switches to the sand and gravel mode, the motor 2 drives the drill bit 3 to sink to the third sampling layer at the third speed (150rpm), the third sampling tube is located in the third sampling layer, and the third sampling tube is extended and retracted to complete the sampling of the third sampling layer, wherein the second current value (2.5A) is greater than the first current value (1.2A), and the third speed (150rpm) is less than the first speed (200rpm);

[0081] When the current detection module detects that the current of the motor 2 is less than the third current value (0.5A) within the first time period (3 consecutive seconds), the sludge stratified sampling device completes sampling, wherein the third current value is less than the first current value.

[0082] In this embodiment, the preferred method is to set three sampling tubes with a maximum unfolded total length of 80cm. The remote terminal is used to pre-set the sampling depth of 0.5m, 1.2m, and 2m. In combination with the actual situation, the sampling parameters of each layer, such as the sampling amount and sampling rate, can be set. The sampling depth and the number of sampling layers can be set according to the different conditions of the reservoir and the different research purposes. The counterweight module makes the device sink to the set depth, and the fixed telescopic rod extends the anchor claw to fix the posture; the ultrasonic sensor and the laser rangefinder jointly verify the actual bottoming position (error ± 1cm) to ensure the accuracy of the sampling position. During the sinking process of the device, the counterweight module ensures that it sinks steadily, and the cooperation of the fixed telescopic rod and the anchor claw enables the device to stabilize its posture after reaching the predetermined depth, ready for sampling. Every time a layer of sediment is reached, a sampling tube is driven to sample. After the three layers of sediment are sampled, the buoyancy chamber 12 releases the air bag, and the device floats to the surface with the sample. After the sampling is completed, the buoyancy chamber 12 is automatically inflated to make the device float to the surface, which is convenient for the operator to recover.

[0083] The depth positioning method of the sampling device of this embodiment is specifically as follows: the ultrasonic sensor (range 0-10m, accuracy ±1cm) arranged at the top of the housing 1 and the laser depth sounder (range 0-2m, accuracy ±0.5mm) at the bottom work together to complete the measurement and control of the sampling depth, wherein the ultrasonic sensor is suitable for preliminary positioning in a larger range and can locate the position of the device more quickly, and the laser depth sounder is close to the bottom of the water for high-precision sampling. The above positioning data is fused through the Kalman filter to eliminate the error caused by the shaking of the water flow, thereby achieving high-precision positioning of the sampling depth and meeting the centimeter-level depth positioning control accuracy. The Kalman filter can fuse the data information of multiple sensors, remove noise and interference, and achieve more accurate depth information, thereby achieving accurate sampling depth control.

[0084] The specific process of setting the number of layers is as follows: the user sets the number of sampling layers (up to 6 layers can be set), and the expansion amount of stratified sampling L = H × (ρs -ρ w ) / ρ w , where H is the height of the stratified water column, ρ s is the density of the sample, and ρ w is the density of water, and automatic stratified sampling is completed. The control software for stratified sampling considers physical quantities such as the water column height, sample density, and water density through the above formula, and can conveniently and quickly calculate the expansion and contraction amounts of the sampling tube in each layer to achieve accurate stratified sampling.

[0085] The actual test data of the control method in this embodiment are as follows:

[0086]

[0087] Table 1. Sampling of conventional silt layer (viscosity 300 cp)

[0088] parameter set value measured value Rotational speed of drill bit 3 80 rpm Actually adjusted to 65 rpm Single-layer sampling time 120s 134s Power consumption of motor 2 24 W (average) 22-27W Interlayer contamination rate ＜3％ 1.9% (fluorescent tracer method)

[0089] Table 2. Sampling of high-viscosity colloidal sludge (4800 cp)

[0090] Explanation of test data: 1) Interlayer contamination rate: The test method for the interlayer contamination rate refers to injecting rhodamine B dye (concentration 1 mg / L) into adjacent layers, and detecting the dye concentration of the lower-layer sample by a spectrophotometer (wavelength 554 nm) after sampling. The contamination rate calculation formula: C 污染 =(C 检测 -C 本底 ) / C 注入 ×100%. The staining tracer test shows that the contamination rate of the traditional sampler is 12% - 25%, while that of this device is only 0.8 - 2.3%, significantly reducing the interlayer contamination and improving the reliability of the sample; 2) Sealing performance: Under a water pressure of 3 bar for 24 hours, the sample leakage volume < 0.1 mL, ensuring the integrity of the sample during collection, storage, and transportation, and avoiding sample loss and data errors caused by leakage; 3) Maximum operating depth: The counterweight test confirms that it can reach 8.2 m in a freshwater environment, meeting the sampling requirements of most reservoirs, lakes and other water areas, and having a wide application prospect.

[0091] By setting up the sampling device of this embodiment, the total height of the device (in the storage state) is 120 cm, which is convenient for transportation and deployment. At the same time, it can be fully expanded during operation to meet the sampling requirements. The minimum distance between adjacent sampling tubes is 5 cm, ensuring the independence of each layer of samples, avoiding mutual interference, guaranteeing the accuracy of sampling data, enabling high-precision stratified sampling, and being able to conduct stratified sampling within the depth range of 0 - 50 cm. The interlayer contamination rate is < 3%, effectively ensuring the accuracy and reliability of the samples, providing high-quality data support for subsequent research. Through precise stratified sampling, information such as the composition and properties of sediment at different depths can be accurately obtained, providing a strong data basis for the research of reservoir sediment. It has better wide adaptability, supports sediments with a viscosity range of 50 - 5000 cP, and the maximum sampling depth for a single operation reaches 8.2 m, being able to meet the sampling requirements of bottom sediments in different types of reservoirs, lakes and other water areas, and having wide applicability. Whether it is low-viscosity mud or high-viscosity colloidal sludge, the device can smoothly complete the sampling task by adaptively adjusting sampling parameters. The multiple sealing structures set ensure that the leakage volume is < 0.1 mL in 24 hours under a water pressure of 3 bar, ensuring the integrity of the samples during collection, storage and transportation, avoiding external contamination or loss of the samples, and the reliable sealing performance guarantees the quality of the samples, enabling the collected samples to truly reflect the actual situation of reservoir sediment. The whole process is automated for sampling, capable of realizing remote command operation and in-situ encoding and marking of samples, which is conducive to onshore or on-board remote operation and management by operators, making the work efficiency higher and also facilitating subsequent classification and analysis, achieving the labeling of samples. The intelligent control makes the operation easier, the work efficiency higher, reduces human intervention, and makes the sampling more accurate and reliable.

[0092] The sampling device of this embodiment can be applied in multiple fields, such as for marine sediment sampling, industrial sludge sampling, etc. Only the drill bit 3 needs to be changed, and the type or size of the drill bit 3 is replaced to adapt to different situations. The adaptation method for marine sediment sampling can adjust the buoyancy, sealing performance, and communication method of the device according to the environmental conditions of the ocean for marine sampling adaptation, and it can be used for marine scientific research. For the adaptation of industrial sludge sampling, the corresponding drill bit 3 can be replaced according to the different properties of the sludge generated by industries (for example, a serrated drill bit 3, a drill bit 3 for hard sediment layers), and the sampling parameters and sample processing operation methods of the device can be adjusted to provide guarantee for the treatment of industrial pollution. For example, the seawater in the ocean is different from the environment of a freshwater reservoir. The salinity, density, and pressure of seawater and other conditions will cause the device to face many inadaptable situations. The buoyancy of the buoyancy chamber 12 can be adjusted accordingly, the corrosion resistance of the sealing chamber can be enhanced, and the communication module can be improved to adapt to the ocean situation. In industrial sludge sampling, due to the different characteristics of the sludge produced by each industry, such as the differences between chemical sludge and paper-making sludge, the corresponding drill bit 3 can be used, and the sampling parameters of the sample and the processing method of the sample can be adjusted to efficiently and correctly achieve the purpose of obtaining industrial sludge samples, which can provide certain reliable data support for the treatment of industrial pollution and environmental monitoring.

[0093] It is easy for those skilled in the art to understand that, on the premise of no conflict, the above advantageous methods can be freely combined and superimposed.

[0094] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention. The above is only the preferred implementation manner of the present invention. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the technical principle of the present invention, several improvements and modifications can still be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A device for stratified sampling of sediment, characterized in that, Comprising: A housing (1), a motor (2), a drill bit (3), and a sample sampling tube; The motor (2) is arranged on the housing (1), an output shaft of the motor (2) passes through the housing (1) along the axial direction of the housing (1), and the output shaft of the motor (2) is connected to the drill bit (3); The sample sampling tube at least comprises a first sampling tube (4) and a second sampling tube (5), the first sampling tube (4) and the second sampling tube (5) are horizontally and hierarchically arranged in the housing (1), and along the axial direction of the housing (1), the hierarchical spacing between the first sampling tube (4) and the second sampling tube (5) is adjustably arranged; along the radial direction of the housing (1), the first sampling tube (4) and the second sampling tube (5) are telescopically arranged so that the first sampling tube (4) and the second sampling tube (5) extend out of the housing (1) for sampling or are retracted into the housing (1) after sampling is completed; One ends of the first sampling tube (4) and the second sampling tube (5) are respectively provided with sample inlets (61), the other ends of the first sampling tube (4) and the second sampling tube (5) are respectively provided with first sealing structures (6), and second sealing structures (7) are arranged on the inner walls of the first sampling tube (4) and the second sampling tube (5).

2. The sediment stratification sampling device according to claim 1, wherein The first sealing structure (6) is a cover, the material of the cover is a shape memory alloy, the cover deforms to seal the corresponding sampling tube, and a solenoid valve (13) is arranged at the sample inlet (601), and the solenoid valve (13) and the cover respectively seal both ends of the corresponding sampling tube.

3. The sediment stratified sampling device according to claim 2, characterized in that, The corresponding sampling tube is provided with a pressure balance hole (801) and a pressure sensor, and the cover deforms according to the pressure difference between the inside and outside of the sampling tube.

4. The sediment stratification sampling device according to claim 1, characterized in that, The second sealing structure (7) comprises a heating wire (701) and a silica gel diaphragm (702), the heating wire (701) is arranged on the inner wall of the corresponding sampling tube, the silica gel diaphragm (702) is adhered to the inner wall circumferential direction of the corresponding sampling tube, and the heating wire (701) is embedded in the silica gel diaphragm (702).

5. The sediment stratified sampling device according to claim 4, wherein, Along the circumferential direction of the corresponding sampling tube, a spiral mounting groove is arranged on the inner wall of the corresponding sampling tube, and the heating wire (701) is mounted in the mounting groove.

6. The sediment stratified sampling device according to any one of claims 1 to 5, characterized in that, Both the first sampling tube (4) and the second sampling tube (5) are of a double-layer tube structure, both the first sampling tube (4) and the second sampling tube (5) comprise an inner tube (81) and an outer tube (82), and the inner tube (81) is telescopically arranged relative to the outer tube (82); A pipe outlet (101) is provided on the outer shell (1), and a third sealing structure (9) is provided at the pipe outlet (101). The third sealing structure (9) includes a sealing ring (901) and a puncturing layer (902). The sealing ring (901) is installed at the pipe outlet (101), and the puncturing layer (902) is provided on the inner peripheral wall of the sealing ring (901). Along the radial direction of the outer shell (1), the inner pipe (81) pierces through the puncturing layer (902) for sampling or is retracted into the outer shell (1) after sampling is completed.

7. The sediment stratified sampling device according to claim 6, characterized in that, Both the first sampling pipe (4) and the second sampling pipe (5) are provided with telescopic assemblies. The telescopic assemblies include an axial electric push rod (10) and a radial electric push rod (11). The axial electric push rod (10) is vertically arranged, one end of the axial electric push rod (10) is connected to the inner wall of the outer shell (1), and the other end of the axial electric push rod (10) is connected to the outer pipe (82). The radial electric push rod (11) is horizontally arranged, one end of the radial electric push rod (11) is connected to the inner wall of the outer shell (1), and the other end of the radial electric push rod (11) is connected to the inner pipe (81).

8. The sediment stratified sampling device according to claim 1, characterized in that, It further includes a buoyancy chamber (12) and a plurality of inertial measurement units. The buoyancy chamber (12) is arranged at the top of the outer shell (1). Along the axial direction of the outer shell (1), the plurality of inertial measurement units are arranged at intervals on the inner wall of the outer shell (1). When the inertial measurement units detect that the inclination angle of the outer shell (1) is greater than a set value, the buoyancy chamber (12) drives the outer shell (1) to float.

9. The sediment stratification sampling device according to claim 1, wherein It further includes an anchoring assembly. The anchoring assembly includes a counterweight, a fixing frame, and a plurality of fixed telescopic rods and anchor claws. The counterweight is arranged at the bottom of the outer shell (1), the fixing frame is arranged on the outer wall of the outer shell (1), the plurality of fixed telescopic rods and the anchor claws are arranged correspondingly, the fixed end of the fixed telescopic rod is connected to the fixing frame, and the movable end of the fixed telescopic rod is connected to the anchor claw.

10. A control method, which is used to control the sediment stratified sampling device according to any one of claims 1 to 9. The sample sampling pipe includes a first sampling pipe (4), a second sampling pipe (5), and a third sampling pipe. The motor (2) has a current detection module and at least three rotation speeds. The control method includes: Adjusting the stratified spacing of the first sampling pipe (4), the second sampling pipe (5), and the third sampling pipe according to the sampling requirements for sediment; Starting the motor (2), the current detection module real-time detects the current of the motor (2). The motor (2) drives the drill bit (3) to sink to the first sampling layer at the first rotation speed. The first sampling pipe (4) is located in the first sampling layer, and the first sampling pipe (4) expands and contracts to complete the sampling of the first sampling layer; When the current detection module detects that the current of the motor (2) is greater than the first current value, the sediment stratified sampling device switches to the silt mode, the motor (2) drives the drill bit (3) to sink to the second sampling layer at the second rotation speed, the second sampling pipe (5) is located in the second sampling layer, and the second sampling pipe (5) expands and contracts to complete the sampling of the second sampling layer, wherein the second rotation speed is greater than the first rotation speed; When the current detection module detects that the current of the motor (2) is greater than the second current value, the sediment stratified sampling device switches to the sand and gravel mode, the motor (2) drives the drill bit (3) to sink to the third sampling layer at the third rotation speed, the third sampling pipe is located in the third sampling layer, and the third sampling pipe expands and contracts to complete the sampling of the third sampling layer, wherein the second current value is greater than the first current value, and the third rotation speed is less than the first rotation speed; When the current detection module detects that the current of the motor (2) is less than the third current value within the first time period, the sediment stratified sampling device completes the sampling, wherein the third current value is less than the first current value.

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