A system and method for underwater non-destructive collection of waterlogged bamboo slips

Abstract

The application discloses a kind of waterlogged parchments underwater nondestructive collection systems and methods.The system includes collection terminal, with power control cabin, transparent storage cylinder and flow field guide head;The bottom of the flow field guide head is provided with annular nozzle array, for generating vortex field in the sediment around parchments, in a non-contact manner to break the physical adhesion of parchments and sediment;Water pump is arranged in the power control cabin, for establishing controlled laminar flow negative pressure field in the transparent storage cylinder, to flexibly suck into the parchments separated from sediment;The bottom of the transparent storage cylinder is provided with openable and closable iris type flexible diaphragm valve, for closing after parchments completely enter to realize underwater in-situ packaging.The application realizes the non-contact flexible extraction and underwater in-situ packaging of fragile waterlogged parchments, avoids physical damage caused by mechanical contact or turbulent impact, and prevents secondary deterioration caused by environmental mutation, improves the safety and success rate of collection.

Description

Technical Field

[0001] This invention relates to the field of underwater archaeological engineering equipment technology, and more specifically, to a non-destructive underwater acquisition system and method for waterlogged bamboo and wooden slips, which is particularly suitable for non-destructive extraction and in-situ encapsulation of structurally fragile waterlogged bamboo and wooden slips in underwater environments such as rivers, lakes and deep seas. Background Technology

[0002] In underwater archaeological excavations, waterlogged bamboo slips are an extremely precious yet exceptionally fragile type of artifact. Due to prolonged immersion in water, the cellulose and hemicellulose in their woody fiber structure have been severely degraded, resulting in extremely low physical strength. They often appear in a colloidal or soft plastic state, and even slight physical contact can cause them to crack or disintegrate. Furthermore, these bamboo slips are usually partially or completely buried in the silt or sediment of riverbeds or lake bottoms, where the surface of the slips adheres strongly to the sediment due to compaction and intermolecular forces.

[0003] Currently, underwater collection methods for such cultural relics have many limitations. Traditional manual retrieval by divers relies heavily on the experience of the operators, but even experienced divers find it difficult to precisely control the pressure with their fingertips using heavy diving gloves, easily leading to uneven pressure and crushing the relics. Using conventional robotic arms mounted on underwater robots for grasping can also cause localized stress concentrations on the rigid gripping surfaces, easily resulting in breakage or indentations of the bamboo slips. Another approach is to use a negative pressure suction pump, which avoids direct rigid contact, but the powerful and uncontrollable turbulent field it generates can exert enormous shearing forces on the bamboo slips, potentially tearing them during the suction process. Simultaneously, the turbulence can also attract surrounding gravel, sand, and other hard debris, causing secondary impact damage to the bamboo slips.

[0004] More importantly, the existing technologies described above all require a transfer process after extracting the bamboo slips from the sediment, namely, transferring them from the collection tool to a pre-filled encapsulation container containing a specific protective liquid. During this transfer, the bamboo slips are inevitably exposed to environments with drastic changes in pressure, temperature, and light, and may even be briefly exposed to air. These environmental abrupt changes accelerate the deterioration of their remaining internal structures. Therefore, how to safely separate the bamboo slips from the highly adhesive underwater sediment without damaging their structural integrity, and how to immediately encapsulate them in their in-situ environment after extraction, is a pressing technical challenge that needs to be solved in the field of underwater archaeology. Summary of the Invention

[0005] The main objective of this invention is to provide a non-destructive underwater acquisition system and method for waterlogged bamboo and wooden slips, so as to solve the technical problems in the background art that physical damage to cultural relics is caused by improper operation and deterioration of cultural relics due to sudden environmental changes.

[0006] To achieve the above objectives, the present invention provides an underwater non-destructive data acquisition system for water-saturated bamboo and wooden slips, comprising:

[0007] The data acquisition terminal includes a power control cabin, a transparent storage cylinder connected to the power control cabin, and a flow field guide head connected to the lower end of the transparent storage cylinder.

[0008] The bottom of the flow field guide head is provided with an annular nozzle array, which is used to generate a vortex field in the sediment around the bamboo slips to break the physical adhesion between the bamboo slips and the sediment in a non-contact manner.

[0009] The power control chamber is equipped with a water pump, which is connected to the transparent storage cylinder. The water pump is used to establish a controlled laminar negative pressure field in the transparent storage cylinder so as to flexibly draw the bamboo slips that have detached from the sediment into the transparent storage cylinder.

[0010] The bottom of the transparent storage cylinder is equipped with an openable and closable iris-type flexible aperture valve, which is used to close after the bamboo slips have completely entered the transparent storage cylinder to achieve underwater in-situ sealing.

[0011] Preferably, the annular nozzle array comprises a plurality of micro-nozzles evenly distributed circumferentially along the bottom edge of the flow field guide head; each micro-nozzle has an inward tilt angle in its spray direction. and tangential deflection angle ; wherein, the inward tilt angle The range is to The tangential deflection angle The range is to This causes the multiple micro-jet streams ejected from the micro-nozzle to converge and form a spiraling upward stripping flow field.

[0012] Preferably, the bottom of the flow field guide head is a downwardly concave bowl-shaped structure, and the annular nozzle array is disposed on the inner circumference of the bowl-shaped structure; the number of the plurality of micro-nozzles is to There are 1, and the orifice diameter of each of the micro-nozzles is 1. millimeters to Millimeters; the micro-nozzle is made of polytetrafluoroethylene or titanium alloy with a hydrophobic coating to prevent sludge particles from clogging it; the inward tilt angle and the tangential deflection angle The combination is precisely configured to ensure that when the spiraling upward stripping flow field acts on the bottom edge of the bamboo slip, its normal impact force component is less than a preset cultural relic safety threshold, while the tangential shear force component is sufficient to overcome the silt adhesion force.

[0013] Preferably, the system further includes: a controller; and a differential pressure sensor, the differential pressure sensor being used to monitor in real time the pressure difference between two endpoints along the axial direction inside the transparent storage cylinder. The controller is electrically connected to the water pump and the differential pressure sensor. The controller internally runs a proportional-integral-derivative (PID) algorithm, based on the pressure difference. As a feedback variable, the speed of the water pump is dynamically adjusted so that the bamboo slips are placed inside the transparent storage cylinder. cm / s to The system increases at a preset velocity of cm / s at a constant speed, ensuring the Reynolds number of the laminar negative pressure field is maintained. Always less than .

[0014] Preferably, the control logic of the PID algorithm is configured to: control the target pressure difference corresponding to the preset speed. As a set value; the real-time pressure difference measured by the differential pressure sensor. As a process variable; calculation error The controller is based on a proportional term. Integral terms and differential terms The sum of these values ​​generates a drive signal for adjusting the water pump; wherein, the proportionality coefficient... Integral coefficient and differential coefficients These are parameters that are pre-calibrated or adaptively adjusted based on the fluid dynamics model, used to minimize velocity overshoot and suppress pressure fluctuations caused by external water flow disturbances.

[0015] Preferably, the acquisition terminal further includes an optical position sensor array, which is arranged along the length of the transparent storage cylinder to detect the real-time position and attitude of the bamboo slip within the transparent storage cylinder and to feed back the detection signal to the controller. In response to the signal from the optical position sensor array, the controller confirms that the bamboo slip has completely passed through the valve port plane of the iris-type flexible aperture valve and outputs a valve closing command to drive the iris-type flexible aperture valve to close.

[0016] This invention also provides a method for underwater non-destructive collection of water-saturated bamboo and wooden slips, comprising the following steps:

[0017] By using an array of annular nozzles at the bottom of the acquisition terminal, microjets are sprayed into the sediment around the bamboo slips to generate a vortex field, which is used to break the physical adhesion between the bamboo slips and the sediment in a non-contact manner.

[0018] A controlled laminar negative pressure field is established in the transparent storage cylinder connected to the annular nozzle array by a water pump in the acquisition terminal, so as to flexibly draw the bamboo slips that have been separated from the sediment into the transparent storage cylinder.

[0019] After confirming that the bamboo slips have completely entered the transparent storage cylinder, the iris-type flexible aperture valve located at the bottom of the transparent storage cylinder is closed to achieve in-situ sealing of the bamboo slips.

[0020] Preferably, the step of generating the vortex field specifically includes: using multiple inwardly tilted angles... for to And it has a tangential deflection angle for to The micro-nozzles synchronously spray high-speed micro-jets to converge at the bottom of the bamboo slips to form a spiraling upward stripping flow field.

[0021] Preferably, the step of establishing the controlled laminar negative pressure field includes: real-time monitoring of the axial pressure difference within the transparent storage cylinder using a differential pressure sensor. Based on the real-time monitored pressure difference The proportional-integral-derivative (PID) algorithm is used to dynamically adjust the speed of the water pump in order to reduce the pressure difference. Stabilizing at a preset target value, thereby maintaining the bamboo slips within the transparent storage cylinder. cm / s to The flow rate increases uniformly at a preset velocity of cm / s, ensuring the Reynolds number of the laminar negative pressure field is maintained. Less than .

[0022] Preferably, before the step of in-situ encapsulating the bamboo slip, the method further includes: detecting the position of the bamboo slip in real time by means of an optical position sensor array arranged along the transparent storage cylinder; when the optical position sensor array confirms that the tail end of the bamboo slip has completely passed through the valve port plane of the iris-type flexible aperture valve, generating and sending a trigger signal to perform the closing step.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] 1. By creating a collaborative working mechanism of "annular micro-jet stripping" and "laminar negative pressure suspension", non-contact flexible extraction of waterlogged bamboo slips is achieved, fundamentally avoiding physical damage caused by mechanical contact or turbulent impact.

[0025] 2. The collection and packaging processes are integrated, and the artifacts are directly sealed underwater using an integrated iris-type flexible aperture valve. This preserves the original hydrochemical environment of the artifacts, prevents secondary deterioration caused by sudden environmental changes, and provides the best initial conditions for subsequent laboratory conservation.

[0026] 3. Based on differential pressure sensor feedback and PID closed-loop control algorithm, the rising speed and flow field state of the bamboo slips during the acquisition process can be precisely controlled, avoiding them from rolling and colliding in the storage cylinder, thus improving the success rate and safety of acquisition.

[0027] 4. Precisely controlled flow fields help to separate most of the mud and sand from the bamboo slips during the stripping stage, reducing the risk of impurities being sucked in along with the bamboo slips and further protecting the microscopic information on the surface of the cultural relics. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the 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.

[0029] Figure 1 This is a schematic diagram of the underwater non-destructive acquisition system for water-saturated bamboo slips provided in an embodiment of the present invention.

[0030] Figure 2 This is a schematic diagram of the flow field guide head provided in an embodiment of the present invention.

[0031] Figure 3 This is a block diagram of the control section of the data acquisition system provided in an embodiment of the present invention.

[0032] Figure 4 This is a flowchart of the underwater non-destructive acquisition method for water-saturated bamboo slips provided in an embodiment of the present invention.

[0033] Figure 5 This is a schematic diagram illustrating the working principle of the data acquisition terminal provided in this embodiment of the invention.

[0034] In the diagram, 100: Data acquisition terminal; 101: Power control cabin; 102: Transparent storage cylinder; 103: Flow field guide head; 104: Iris-type flexible aperture valve; 201: Annular nozzle array; 202: Miniature nozzle. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some 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 are within the scope of protection of the present invention.

[0036] Example 1

[0037] This embodiment provides an underwater non-destructive data acquisition system for water-saturated bamboo and wooden slips. For example... Figure 1 As shown, this system is typically mounted on deep-sea platforms such as underwater robots, and is connected to the main body of the underwater robot via a flexible umbilical cable to obtain power and communication. The core component of the system is the data acquisition terminal 100.

[0038] The data acquisition terminal 100 includes, from top to bottom, a power control cabin 101, a transparent storage cylinder 102, and a flow field guide head 103.

[0039] The power control compartment 101 is constructed from high-strength materials such as pressure-resistant aluminum alloy, and features a standard flange interface at its upper end for connection to the end effector of the underwater robot's robotic arm. Internally, it integrates the core power and control unit, including a miniature variable frequency water pump 304, related fluid control valve assemblies, and a controller 301 (such as...) that serves as the system's brain. Figure 3 (As shown).

[0040] The transparent storage cylinder 102 is made of high-strength polycarbonate material, possessing excellent pressure resistance and optical transparency, facilitating real-time observation of the internal contents by external camera equipment. Its inner diameter is designed to be approximately [missing information - likely a percentage] of the average width of the bamboo slips to be collected. to The upper end of the transparent storage cylinder 102 is connected to the power control compartment 101 via a quick-release buckle, and the connection is equipped with a double-layer rubber sealing ring to ensure watertightness; its lower end is connected to the flow field guide head 103.

[0041] At the bottom of the transparent storage cylinder 102, where it connects to the flow field guide head 103, an openable and closable iris-type flexible aperture valve 104 is installed. This valve consists of multiple overlapping Teflon blades, the edges of which are wrapped with a flexible silicone layer. During data collection, the valve is fully open, creating a clear collection channel; after collection is complete, the valve closes, utilizing the elasticity of the silicone layer to achieve a flexible water seal at the bottom of the storage cylinder.

[0042] like Figure 2As shown, the flow field guide head 103 is the core component for achieving non-contact stripping. It is generally funnel-shaped and made of a flexible, cartilage-like polyurethane material to provide cushioning during slight contact with the riverbed. The key structure at its bottom is the annular nozzle array 201. This array consists of multiple micro-nozzles 202 evenly distributed circumferentially along the bottom edge of the flow field guide head 103. In a preferred embodiment, the number of micro-nozzles 202 is... to One, can be set to Each micro-nozzle 202 has an orifice diameter of [number missing]. millimeters to millimeters, preferably millimeters to Millimeters. To prevent tiny particles in underwater silt from clogging the nozzle, it can be made of polytetrafluoroethylene with low surface energy, or the inner wall of the titanium alloy nozzle can be treated with a hydrophobic coating.

[0043] Specifically, the jet axis of each micro-nozzle 202 is precisely designed and is not vertically downward. Its jet direction also has an inward tilt angle. and a tangential deflection angle Inward tilt angle The range is to Tangential deflection angle The range is to In a specific implementation, the tangential deflection angle Can be set to When supplied by an external high-pressure water source (provided by a high-pressure water pump carried by an underwater robot, with a pressure range of...) - When water at a pressure of (MPa) is ejected through these micro-nozzles 202, multiple micro-jets do not directly impact the bamboo slips themselves. Instead, they converge in the sediment beneath the slips, forming a stable and controllable spiral upward stripping flow field. This flow field acts on the sediment through tangential shear force, utilizing the thixotropic effect of the silt to liquefy it in localized areas. This non-contact method breaks down the physical adhesion between the bamboo slips and the sediment, putting the slips into a quasi-suspended state, thus creating conditions for subsequent flexible suction.

[0044] like Figure 3As shown, the control section of this system is centered around controller 301. Controller 301 can be a microprocessor or a field-programmable gate array (FPGA), which is electrically connected to various sensors and actuators via an internal bus. The system also includes a power supply module for powering the entire acquisition terminal, sensor interface circuitry for conditioning and converting sensor signals, and a communication interface for communicating with the underwater robot's main control system.

[0045] To achieve flexible suction of the bamboo and wooden slips, the system is equipped with a differential pressure sensor 302, which is used to monitor the pressure difference between the two ends along the axial direction inside the transparent storage cylinder 102 in real time. The miniature variable frequency water pump 304 inside the power control compartment 101 does not simply pump water at a constant power, but rather establishes a negative pressure zone at the top of the transparent storage cylinder 102 through the Venturi effect, and its rotational speed is controlled by the controller 301. The controller 301 internally operates a proportional-integral-derivative (PID) closed-loop control algorithm. The control logic of this algorithm is as follows: first, a value related to the target upward speed (… cm / s to The target pressure difference (cm / s) This is used as the set value. Then, the pressure difference measured in real time by the differential pressure sensor 302 is used. As a process variable, controller 301 continuously calculates the error between the two. .

[0046] Specifically, based on this error, controller 301 performs proportional, integral, and derivative operations to generate a drive signal for adjusting the micro variable frequency water pump 304. In a preferred embodiment, this calculation logic is implemented using the following formula:

[0047]

[0048] in, This is the control signal output to the water pump driver; This represents the pressure difference error at the current moment. This is a proportionality coefficient used to quickly respond to errors; These are the integral coefficients used to eliminate steady-state errors; These are differential coefficients used to predict error trends and suppress system oscillations. These coefficients are parameters pre-calibrated based on the fluid dynamics model or adaptively adjusted in actual operation to minimize velocity overshoot and suppress pressure fluctuations caused by external water flow disturbances.

[0049] To precisely trigger the encapsulation action, the acquisition terminal 100 is also equipped with an optical position sensor array 303. This array can consist of multiple pairs of laser beam sensors or linear vision sensors, arranged along the length of the transparent storage cylinder 102. It can detect the position and attitude of the bamboo slips within the storage cylinder in real time. When the controller 301 determines from the signals received from the optical position sensor array 303 that the tail end of the bamboo slip has completely passed through the valve port plane of the iris-type flexible aperture valve 104, it will immediately output a valve closing command, driving a micro servo motor to control the iris-type flexible aperture valve 104 to slowly close, completing the underwater in-situ encapsulation.

[0050] Example 2

[0051] This embodiment provides a method for underwater non-destructive acquisition of water-saturated bamboo slips, which is based on the system described in Embodiment 1. Figure 4 As shown, the method includes the following steps:

[0052] Step S401: Positioning and Flow Field Separation. Using the camera system mounted on the underwater robot, the operator aligns the flow field guide head 103 of the acquisition terminal 100 with and slowly approaches the water-saturated bamboo slip to be collected. After maintaining a safe distance between the bottom of the guide head and the sediment surface, the annular nozzle array 201 is activated. High-pressure water flows through the slip at a specific inward tilt angle. ( to and tangential deflection angle ( to Multiple micro-nozzles 202 generate an upward spiral vortex field in the sediment surrounding the bamboo slips. This vortex field acts gently on the sediment in a non-contact manner through shear force, breaking the physical adhesion between the bamboo slips and the sediment, thus loosening the bamboo slips from the silt.

[0053] Step S402: Laminar Flow Suspension Inhalation. Simultaneously or shortly after the annular nozzle array 201 begins operation, the controller 301 activates the miniature variable frequency water pump 304 within the power control chamber 101, establishing a controlled laminar negative pressure field within the transparent storage cylinder 102. This process is a closed-loop control process: the differential pressure sensor 302 monitors the axial pressure difference within the storage cylinder in real time. And this feedback is sent to controller 301. Controller 301 uses a PID algorithm to calculate the real-time pressure difference. Pressure difference from the preset target The speed of the micro-variable frequency pump 304 is compared and dynamically adjusted. This is intended to precisely maintain a weak and stable negative pressure, allowing the bamboo slips that have detached from the sediment to be gently guided at a low preset speed. cm / s to The transparent storage cylinder 102 is drawn in at a uniform rate of (cm / s). Simultaneously, by precisely controlling the flow rate, the Reynolds number of the flow field inside the cylinder is ensured. Always less than To maintain laminar flow.

[0054] Step S403: Real-time position monitoring. During the process of the bamboo slips being sucked into the transparent storage cylinder 102, the optical position sensor array 303 arranged along the cylinder wall continuously operates, detecting the position and orientation of the bamboo slips in real time and feeding the data back to the controller 301. The controller 301 then determines whether the bamboo slips have completely entered the storage cylinder.

[0055] Step S404: In-situ encapsulation. When the signal from the optical position sensor array 303 indicates that the tail end of the bamboo slip has completely passed through the valve port plane of the iris-type flexible aperture valve 104, the controller 301 generates and sends a trigger signal. This signal can, on the one hand, instruct the annular nozzle array 201 to stop spraying, and on the other hand, drive the servo motor of the iris-type flexible aperture valve 104 to close its blades. After the valve closes, the bamboo slip, along with the surrounding in-situ water sample, is sealed together in the transparent storage cylinder 102, realizing the integrated operation of collection and encapsulation.

[0056] like Figure 5 As shown, the working principle of this invention lies in a synergistic mechanism of "loosening the soil first, then suspending it, and finally encapsulating it." If there is only negative pressure at the top, an extremely large suction force must be applied to overcome the adhesion of the silt, which would cause the bamboo slips to accelerate instantaneously and impact the top of the cylinder or be torn apart by turbulence. In this scheme, the annular jet first creates a localized liquefaction zone at the bottom of the bamboo slips, almost completely eliminating adhesion resistance, placing the bamboo slips in a near-zero-gravity state for collection. At this point, only a weak, precisely controlled negative pressure from the top, controlled by a PID algorithm, is needed to guide the bamboo slips to rise smoothly with the laminar water flow. This synergistic mechanism ensures that the fragile, water-saturated bamboo slips do not suffer any harmful mechanical stress or fluid shear force throughout the collection process.

[0057] In summary, this application achieves integrated in-situ encapsulation by combining a ring-shaped microjet array with a controlled laminar negative pressure field and an iris-type flexible aperture valve. This not only solves the technical problem of the difficulty in completely extracting waterlogged bamboo slips in underwater high-adhesion environments, but also effectively avoids secondary degradation by maintaining the original hydrochemical environment of the artifacts. This provides an efficient, safe, and scientific solution for artifact collection in the field of underwater archaeology.

[0058] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A system for underwater non-destructive collection of waterlogged parchments, characterized in that, include: The data acquisition terminal includes a power control cabin, a transparent storage cylinder connected to the power control cabin, and a flow field guide head connected to the lower end of the transparent storage cylinder. The bottom of the flow field guide head is provided with an annular nozzle array, which is configured to spray fluid into the sediment around the bamboo slips to form a separation vortex field. The power control compartment is equipped with a water pump, which is connected to the transparent storage cylinder and is configured to establish a laminar negative pressure field inside the transparent storage cylinder, thereby guiding the bamboo slips into the transparent storage cylinder; The bottom of the transparent storage cylinder is equipped with an openable and closable iris-type flexible aperture valve. The blade edge of the iris-type flexible aperture valve is covered with an elastic sealing material and is configured to retract and close when a closing command is received, thereby sealing the bottom opening of the transparent storage cylinder through the compression deformation of the elastic sealing material.

2. The underwater non-destructive data acquisition system for water-saturated bamboo and wooden slips according to claim 1, characterized in that, The annular nozzle array includes multiple micro-nozzles evenly distributed circumferentially along the bottom edge of the flow field guide head; each micro-nozzle has an inward tilt angle in its spray direction. and tangential deflection angle ; wherein, the inward tilt angle The range is to The tangential deflection angle The range is to This causes the multiple micro-jet streams ejected from the micro-nozzle to converge and form a spiraling upward stripping flow field.

3. The underwater non-destructive data acquisition system for water-saturated bamboo and wooden slips according to claim 2, characterized in that, The bottom of the flow field guide head is a downwardly concave bowl-shaped structure, and the annular nozzle array is disposed on the inner circumference of the bowl-shaped structure; the number of the plurality of micro-nozzles is to There are 1, and the orifice diameter of each of the micro-nozzles is 1. millimeters to The micro-nozzle is made of polytetrafluoroethylene or titanium alloy with a hydrophobic coating. The combination of the inward tilt angle and the tangential deflection angle is configured such that when the spiral upward flow field acts on the bottom region of the bamboo slip, its tangential velocity component is greater than its normal velocity component.

4. The underwater non-destructive data acquisition system for water-saturated bamboo and wooden slips according to claim 1, characterized in that, The system also includes: Controller; A differential pressure sensor is used to monitor in real time the pressure difference between two points along the axial direction inside the transparent storage cylinder. ; The controller is electrically connected to the water pump and the differential pressure sensor. The controller internally runs a proportional-integral-derivative (PID) algorithm, based on the pressure difference. As a feedback variable, the speed of the water pump is dynamically adjusted so that the bamboo slips are placed inside the transparent storage cylinder. cm / s to The system increases at a preset velocity of cm / s at a constant speed, ensuring the Reynolds number of the laminar negative pressure field is maintained. It is always less than 2300.

5. The underwater non-destructive data acquisition system for water-saturated bamboo and wooden slips according to claim 4, characterized in that, The control logic of the PID algorithm is configured to: control the target pressure difference corresponding to the preset speed. As a set value; the real-time pressure difference measured by the differential pressure sensor. As a process variable; calculation error The controller is based on a proportional term. Integral terms and differential terms The sum of these values ​​generates a drive signal for adjusting the water pump; wherein, the proportionality coefficient... Integral coefficient and differential coefficients These are parameters that are pre-calibrated or adaptively adjusted based on the fluid dynamics model.

6. The underwater non-destructive data acquisition system for water-saturated bamboo and wooden slips according to claim 4, characterized in that, The acquisition terminal also includes an optical position sensor array, which is arranged along the length of the transparent storage cylinder and configured to detect the real-time position and orientation of the bamboo slip within the transparent storage cylinder and feed the detection signal back to the controller. The controller, in response to the signal from the optical position sensor array, is configured to output a valve closing command to drive the iris-type flexible aperture valve to close after confirming that the bamboo slip has completely passed through the valve port plane of the iris-type flexible aperture valve.

7. A method for underwater non-destructive collection of water-saturated bamboo and wooden slips, characterized in that, Includes the following steps: By using an array of annular nozzles at the bottom of the acquisition terminal, microjets are sprayed into the sediment around the bamboo slips to generate a vortex field, which is used to break the physical adhesion between the bamboo slips and the sediment in a non-contact manner. A controlled laminar negative pressure field is established in the transparent storage cylinder connected to the annular nozzle array by a water pump in the acquisition terminal, so as to flexibly draw the bamboo slips that have been separated from the sediment into the transparent storage cylinder. After confirming that the bamboo slips have completely entered the transparent storage cylinder, the iris-type flexible aperture valve located at the bottom of the transparent storage cylinder is closed to achieve in-situ sealing of the bamboo slips.

8. The method according to claim 7, characterized in that, The step of generating the vortex field specifically includes: using multiple inwardly tilted angles... for to And it has a tangential deflection angle for to The micro-nozzles synchronously spray high-speed micro-jets to converge at the bottom of the bamboo slips to form a spiraling upward stripping flow field.

9. The method according to claim 7, characterized in that, The steps for establishing the controlled laminar negative pressure field include: The axial pressure difference inside the transparent storage cylinder is monitored in real time using a differential pressure sensor. ; Based on the real-time monitored pressure difference The proportional-integral-derivative (PID) algorithm is used to dynamically adjust the speed of the water pump in order to reduce the pressure difference. Stabilizing at a preset target value, thereby maintaining the bamboo slips within the transparent storage cylinder. cm / s to The flow rate increases uniformly at a preset velocity of cm / s, ensuring the Reynolds number of the laminar negative pressure field is maintained. Less than .

10. The method according to claim 7, characterized in that, Prior to the step of in-situ encapsulation of the bamboo slips, the method further includes: The position of the bamboo slips is detected in real time by an array of optical position sensors arranged along the transparent storage cylinder; When the optical position sensor array confirms that the tail end of the bamboo slip has completely passed through the valve port plane of the iris-type flexible aperture valve, a trigger signal is generated and sent to execute the closing step.

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