Seabed-based in-situ detection system based on force-distance adaptive adjustment

Abstract

The invention belongs to the technical field of seabed static penetration tests of ocean observation probe rods, and particularly provides a seabed-based in-situ detection system based on force-distance self-adaptive adjustment, which comprises a plurality of gears, and a gear selection table is formed by the relationship between penetration forces and the relationship between penetration strokes of n gears and is used for gear selection; the method comprises the steps that S1, a gear is selected for first injection; s2, gear shifting penetration resistance is calculated according to data detected during previous penetration, the gear shifting penetration resistance is compared with the penetration force in the gear selection table, and according to the principle that the penetration force is larger than the penetration resistance, a gear is selected in the gear selection table for second penetration; and S2 is repeated, and gear selection and penetration of 3-m penetration are completed in sequence. Under the condition that the redundancy of the penetration force is large, the penetration force is reduced in an upshift mode, a larger penetration stroke is obtained, the capacity of equipment is effectively utilized, energy waste is reduced, the number of penetration times is reduced, noise in detection data is reduced, and the later data processing difficulty is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of seabed static penetration test of ocean observation rods, and particularly relates to a seabed-based in-situ detection system based on force-distance adaptive adjustment. Background Art

[0002] As human exploration and development of the ocean gradually enter the deep and far sea era, the dependence on ocean detection equipment is increasing. The penetration of seabed observation probes is the most direct and accurate means of obtaining sediment property parameters. The seabed observation probe is installed on the observation rod, and the penetration methods of the seabed observation rod are mainly dynamic penetration and static penetration.

[0003] For static penetration, the existing static penetration device has a working mode of fixed penetration force and penetration stroke, and has the following disadvantages: First, due to the different hardness of the longitudinal distribution of soil layers, there is redundant penetration force in the work of the existing device, resulting in waste; Second, the acceleration and deceleration phenomena that occur in the start and stop stages of each penetration stroke make the detection data have noise, and data processing is required to reduce the influence of noise on data accuracy. Summary of the Invention

[0004] To solve the defects existing in the prior art, the present invention proposes a seabed-based in-situ detection system based on force-distance adaptive adjustment, which can select an appropriate penetration force for penetration according to the actual load. The scheme is as follows: The seabed-based in-situ detection system based on force-distance adaptive adjustment includes multiple gears. According to the penetration force in the gears from low to high as gear 1 to gear n, n>1, the relationship between the penetration forces of the n gears and the relationship between the penetration strokes are formed into a gear selection table for gear selection; The method includes the following steps: Step S1, the first penetration; Step S2, calculate the shift penetration resistance according to the data detected during the previous penetration, compare the shift penetration resistance with the penetration force in the gear selection table, and select an appropriate gear in the gear selection table for the second penetration according to the principle that the penetration force is greater than the penetration resistance; Repeat step S2 to complete the gear selection and penetration of the 3rd to mth penetrations in sequence, m>3.

[0005] Further, in step S1, if the properties of the surface soil layer to be penetrated are known, calculate the initial penetration resistance and query the gear selection table to select a gear; if the properties of the surface soil layer to be penetrated are unknown, select gear n.

[0006] Further, if the first penetration stroke can be completed completely, there is no need to downshift; if the first penetration stroke cannot be completed, downshifting is required.

[0007] Further, in step S2, the detected data are the tip resistance and the side friction resistance. Substitute the data into the shifting penetration resistance formula to obtain the shifting penetration resistance. Among them, the shifting penetration resistance formula is: In the formula: —— The maximum total tip resistance obtained in the previous penetration stroke; —— times of the cumulative total side wall friction; —— A constant, and its value range is 1.05 to 1.2; —— The diameter of the sounding rod; —— The penetration depth of the sounding rod in the same homogeneous soil mass; —— The bottom area of the probe cone; —— The total contact area between the side wall of the sounding rod and the soil; q c —— The tip resistance; q ci —— i The tip resistance at time p —— The number of detections; f s —— The side friction resistance.

[0008] Further, the penetration force in the low gear is large and the penetration stroke is small, while the penetration force in the high gear is small and the penetration stroke is large. During the change from the 1st gear to the nth gear, the penetration force gradually decreases and the penetration stroke gradually increases.

[0009] Further, the gear selection judgment rule is that the penetration force corresponding to the gear in the gear selection table is the closest to the shifting penetration resistance and greater than the shifting penetration resistance.

[0010] Furthermore, the seabed in-situ detection system includes a pulley assembly, a traction rope, a clamping manipulator, a probe rod and a driving device, the traction rope is wound around the pulley assembly, the traction rope and the clamping manipulator are fixedly connected, the clamping manipulator clamps the probe rod, the pulley assembly includes a plurality of pulleys, and the driving device provides power for the pulley assembly and the traction rope movement respectively; the method for obtaining the gear selection table is as follows: by changing the number of movable pulleys and fixed pulleys in the pulley assembly and the distance between the pulleys, the ratio of the driving speed driven by the driving device and the penetration speed at the output end is changed, or by changing the number of movable pulleys and fixed pulleys in the pulley assembly and the position between the pulleys and combining the traction rope movement, the ratio of the driving speed driven by the driving device and the penetration speed at the output end is changed, thereby changing the penetration force, penetration stroke and penetration speed of the probe rod, and recording the penetration force, penetration stroke and penetration speed in the above-mentioned multiple situations to form a gear selection table.

[0011] Compared with the prior art, the advantages of the present invention are as follows: The seabed-based in-situ detection system of the present invention sets different gears to adapt to different working environments, selects appropriate penetration force according to actual load, and when the existing penetration force redundancy is large, shifts up to reduce the size of the penetration force to obtain a larger penetration stroke; when the existing penetration force is insufficient, downshifts to reduce the penetration stroke by changing the ratio of the driving speed of the driving device and the penetration speed of the output end, thereby obtaining a larger penetration force and completing the penetration operation.

[0012] When the penetration force redundancy is large, the present invention shifts up to reduce the size of the penetration force to obtain a larger penetration stroke. Compared with the prior art, it can not only make effective use of the equipment's production capacity and reduce energy waste, but also reduce the number of penetrations, that is, reduce the number of acceleration and deceleration times that occur in the start and stop stages of each penetration stroke, thereby reducing the noise in the detection data, reducing the difficulty of subsequent data processing, and making data collection more stable and reliable.

[0013] The applicant has discovered through previous penetration work that there are small areas of soil in the seabed that contain organisms (remains of shellfish and crustaceans, coral reefs, etc.), rocks (granite, sandstone, limestone, etc.), seabed garbage and artificial obstacles. The presence of these will cause the penetration resistance to increase instantly, affecting the penetration process. When encountering such extreme conditions, the present invention can reduce the penetration stroke by quickly downshifting, attempt to penetrate without damaging the probe, and increase the penetration force to achieve "penetration" of these small amounts of extremely hard soil layers. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the main structure of the seabed in-situ detection system according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the pulley assembly state in the first gear of the embodiment of the present invention.Figure 1 ; Figure 3 It is a schematic diagram of the pulley assembly state in the first gear of the embodiment of the present invention Figure 2 ; Figure 4 It is a schematic diagram of the pulley assembly state in the first gear of the embodiment of the present invention Figure 3 ; Figure 5 It is a schematic diagram of the pulley assembly state in the second gear of the embodiment of the present invention Figure 1 ; Figure 6 It is a schematic diagram of the pulley assembly state in the second gear of the embodiment of the present invention Figure 2 ; Figure 7 It is a schematic diagram of the pulley assembly state in the second gear of the embodiment of the present invention Figure 3 ; Figure 8 It is a schematic diagram of the pulley assembly state in the third gear of the embodiment of the present invention Figure 1 ; Figure 9 It is a schematic diagram of the pulley assembly state in the third gear of the embodiment of the present invention Figure 2 ; Figure 10 It is a schematic diagram of the pulley assembly state in the third gear of the embodiment of the present invention Figure 3 ; Figure 11 It is a schematic diagram of the pulley assembly state in the fourth gear of the embodiment of the present invention Figure 1 ; Figure 12 It is a schematic diagram of the pulley assembly state in the fourth gear of the embodiment of the present invention Figure 2 ; Figure 13 It is a schematic diagram of the pulley assembly state in the fourth gear of the embodiment of the present invention Figure 3 ; Figure 14 It is a schematic diagram of the pulley assembly state in the fifth gear of the embodiment of the present invention Figure 1 ; Figure 15 It is a schematic diagram of the pulley assembly state in the fifth gear of the embodiment of the present invention Figure 2 ; Figure 16 It is a schematic diagram of the pulley assembly state in the fifth gear of the embodiment of the present invention Figure 3 ; Figure 17 It is a schematic diagram of the pulley assembly state in the sixth gear of the embodiment of the present invention Figure 1 ; Figure 18 It is a schematic diagram of the pulley assembly state in the sixth gear of the embodiment of the present invention Figure 2 ; Figure 19 It is a schematic diagram of the pulley assembly state in the seventh gear of the embodiment of the present invention Figure 1 ; Figure 20 Schematic diagram of the pulley assembly in the seventh gear of the embodiment of the present invention Figure 2 ; Figure 21 Schematic diagram of the pulley assembly in the eighth gear of the embodiment of the present invention Figure 1 ; Figure 22 Schematic diagram of the pulley assembly in the eighth gear of the embodiment of the present invention Figure 2 .

[0015] In the above figures: 1. Frame; 2. Pulley AI; 3. Pulley AII; 4. Pulley BI; 5. Pulley BII; 6. Pulley CI; 7. Pulley CII; 8. Pulley DI; 9. Pulley DII; 10. Pulley GI; 11. Pulley GII; 12. Towing rope; 13. Rope connection point E; 14. First clamping part; 15. Second clamping part; 16. Probe rod. Detailed implementation manners

[0016] For the convenience of those skilled in the art to understand the present invention, the following combines the drawings to illustrate the detailed implementation manners of the present invention.

[0017] As Figures 1 - 22 shown, the present invention proposes a seabed-based in-situ detection system based on force-distance adaptive adjustment. The seabed-based in-situ detection system includes multiple gears, from low to high as gears 1 to n. The relationships between the penetration forces and the penetration strokes of the n gears are formed into a gear selection table for gear selection.

[0018] Specifically, the penetration force in the low gear is large and the penetration stroke is small, while the penetration force in the high gear is small and the penetration stroke is large. During the change from gear 1 to gear n, the penetration force gradually decreases and the penetration stroke gradually increases.

[0019] The method of the seabed-based in-situ detection system includes the following steps: Step S1: Select a gear for the first penetration.

[0020] There are two forms of gear selection: Form 1: Given the properties of the penetrated surface soil layer, calculate the initial penetration resistance, and query the gear selection table according to the principle that the penetration force is greater than the penetration resistance to select a suitable gear. Specifically, before the equipment works, the appropriate gear can be selected by using the properties of the surface soil layer in the local area. For example, the maximum penetration force of this system F 0 Taking 2.5t as an example for illustration, assuming that the properties of the existing shallow seabed soil layer in a certain sea area are known, and the ultimate bearing capacity of the surface soil layer, that is, the required penetration resistance, is , select to query the gear selection table and select the fifth gear for the first penetration.

[0021] Form 2: When the properties of the penetrated surface soil layer are unknown, select a high gear, i.e., the nth gear. Specifically, if there is no relevant soil layer data, according to experience, the surface soil layer is generally soft in general cases. Therefore, the principle of giving priority to high gears can be adopted. In this embodiment, the first penetration is completed in the eighth gear.

[0022] If the first penetration stroke can be completed completely, based on the data obtained from the first penetration stroke, determine whether to upshift or keep the gear unchanged for the next penetration stroke. It should be noted that in the subsequent upshift control strategy, upshifting should be carried out after the entire current penetration stroke is completed. This operation is to reduce energy consumption and achieve the purpose of not wasting the penetration stroke and reducing the start-stop frequency of penetration. If the first penetration stroke cannot be completed, it indicates that the penetration resistance is greater than the penetration force, and downshifting is required to increase the penetration force.

[0023] Step S2: Calculate the shift penetration resistance based on the data detected during the previous penetration, compare the shift penetration resistance with the penetration force in the gear selection table, and select a suitable gear in the gear selection table for the second penetration. The selection principle is that the penetration force in the gear is the closest to and greater than the shift penetration resistance.

[0024] Among them, the formula for the shift penetration resistance is: In the formula: —— The maximum total resistance on the cone tip obtained in the previous penetration stroke; —— times the cumulative total sidewall friction force; —— Obtained by comprehensively analyzing the existing penetration data, is a constant, and its value range is 1.05 - 1.2; for the purpose of this invention to complete the penetration task, therefore, in order to obtain a relatively large shift penetration resistance for judgment , in this embodiment, is preferably taken as 1.2; —— The diameter of the sounding rod; —— The penetration depth of the sounding rod in the same homogeneous soil mass; —— The bottom area of the probe cone; —— The total area of contact between the sidewall of the sounding rod and the soil; q c —— The cone tip resistance; q ci —— iTip resistance of the moment cone; p —— Number of detections; f s —— Skin friction.

[0025] Repeat step S2 to complete the gear selection and penetration for the 3rd to mth penetrations in sequence.

[0026] The seabed-based in-situ detection system of the present invention is provided with different gears to adapt to different working environments, selects an appropriate penetration force for penetration according to the actual load, and when there is a large redundancy of the existing penetration force, shifts up the gear to reduce the magnitude of the penetration force to obtain a larger penetration stroke; when the existing penetration force is insufficient, downshifts by changing the ratio of the speed driven by the driving device to the penetration speed at the output end to reduce the penetration stroke to obtain a larger penetration force and complete the penetration operation.

[0027] The applicant also found based on previous penetration work that there are small areas in the seabed soil layer containing biological substances (such as remains of shellfish and crustaceans, coral reefs, etc.), rock substances (such as granite, sandstone, limestone, etc.), seabed garbage, and artificial obstacles. These existences will cause the penetration resistance to increase instantaneously and affect the penetration process. When encountering such extreme conditions, the present invention can perform a rapid downshift operation to reduce the penetration stroke, attempt to penetrate without damaging the probe head, and increase the penetration force to "penetrate" these small amounts of extremely hard soil layers.

[0028] Specifically, as Figure 1 shown, the seabed-based in-situ detection system includes a frame 1, a pulley assembly, a towing rope 12, a clamping manipulator, a probe rod, and a driving device. The pulley assembly is installed on the frame 1, the towing rope 12 is wound around the pulley assembly, the towing rope 12 is fixedly connected to the clamping manipulator, the clamping manipulator clamps the probe rod 16, the pulley assembly includes several pulleys, every two are in a group and arranged vertically, and the driving device provides power for the movement of the pulley assembly and the towing rope respectively.

[0029] A probe head is installed at the end of the probe rod 16, and a detection device is provided on the probe head. The detection device is a sensor for detecting the penetration resistance. In this embodiment, a double-bridge probe head is selected, and the sensors installed thereon can simultaneously measure the tip resistance and the skin friction, which is suitable for testing complex soil conditions.

[0030] The seabed-based in-situ detection system further includes a control system, and the control system is connected to the driving device, the detection device, and the clamping manipulator.

[0031] Change the number of movable pulleys and fixed pulleys in the pulley assembly and the distance between the pulleys to change the ratio of the driving speed of the driving device to the penetration speed of the output end, or change the ratio of the driving speed of the driving device to the penetration speed of the output end by changing the number of movable pulleys and fixed pulleys in the pulley assembly and their positions and combining with the movement of the towing rope, thereby changing the penetration force, penetration stroke and penetration speed of the probe rod to form multiple gears. The penetration speed of the output end here is the penetration speed of the probe rod. In this application, the driving speed of the driving device is defined as a constant state and runs at a uniform speed.

[0032] Specifically, the pulley assembly includes several groups of variable pulleys and one group of fixed pulleys. One group of fixed pulleys is close to the clamping manipulator. According to the detection data of the probe penetration force, the number of variable pulleys can be adjusted, and it can be freely switched from the movable pulley stage to the fixed pulley stage or from the fixed pulley stage to the movable pulley stage. Each group of variable pulleys can move relatively and towards each other freely, changing the ratio of the driving speed of the driving device to the penetration speed of the output end, so as to change the magnitude of the penetration force at the probe rod, and correspondingly change the penetration speed and penetration stroke of the probe rod, so that the present invention has more movement forms and forms different gears. The driving device realizes the movement of several groups of variable pulleys through a transmission mechanism, and the transmission mechanism can be a rack and pinion mechanism.

[0033] As Figure 1 shown, in this embodiment, the pulley assembly includes four groups of variable pulleys A, B, C, D and one group of fixed pulleys G. Specifically, pulley AI 2, pulley AII 3, pulley BI 4, pulley BII 5, pulley CI 6, pulley CII 7, pulley DI 8, pulley DII 9 are variable pulleys, and the driving device is controlled by a control system to drive the pulleys to realize the mutual switching of movable pulleys and fixed pulleys. Pulley GI 10 and pulley GII 11 are fixed pulleys, arranged up and down. Pulley GII 11 is used to change the direction of force, and a spring tensioning structure is arranged on pulley GI 10 to prevent the rope from loosening and affecting the normal progress of the penetration work.

[0034] The total length of the towing rope remains unchanged, and it is wound around each pulley to form a closed loop. Here, the closed loop means that the towing rope is in the shape of a ring with the head and tail connected.

[0035] The towing rope is made of a material with high tensile strength and toughness. In this embodiment, a steel wire rope is selected as an example for illustration.

[0036] Specifically, as Figure 1As shown, a rope connection point E13 is defined on the towing rope as the positioning connection point when connected to the driving device. In this embodiment, to facilitate the calculation of the ratio of the speed driven by the driving device to the penetration speed of the output end, when the variable pulleys are all fixed pulleys, the rope connection point E13 is set at the midpoint of the towing rope between pulley AI2 and pulley AII3. The driving device can provide an upward or downward force at the rope connection point E.

[0037] The clamping manipulator, used to clamp the sounding rod, includes a first clamping part 14 and a second clamping part 15, which are arranged vertically, so that the position of the sounding rod is fixed and no deviation occurs during penetration. The first clamping part 14 is fixedly connected to the towing rope 12, and the movement of the towing rope 12 drives the sounding rod 16 to move up and down, ensuring a constant penetration speed for each penetration stroke. The second clamping part 15 is used to clamp the sounding rod and moves synchronously with the sounding rod.

[0038] As Figure 2 shown, the position K in the figure is the initial position of the first clamping part 14. The position of the first clamping part 14 changes as it moves with the towing rope 12, changing from K point to point, as Figure 3 , 4 shown.

[0039] In the seabed cone penetration test (CPT) system, the working efficiency of the hydraulic station is constant. In this embodiment, the power is provided by a hydraulic pump station, with a hydraulic cylinder as the driving device and a clamping manipulator as the penetration execution device to cooperate to complete the penetration task.

[0040] To simplify the calculation, in this embodiment, the same type of pulleys is selected in the pulley assembly, that is, the mass and diameter of the pulleys are the same.

[0041] To more clearly express the position information of each working state of the present invention, as Figures 2 - 22 shown, the position is described in the form of a grid for assistance, where the vertical distance between small grids is defined as , which is the radius length of the pulley, and the vertical distance between large grids is defined as - 2r , where h is the maximum penetration stroke achieved by the device.

[0042] The calculation processes of the penetration force, penetration stroke, and penetration speed for each gear are introduced in detail below.

[0043] First gear: As Figure 2As shown, all the pulleys are fixed pulleys. When the driving device acts directly on the rope connection point E, E moves upward. Define its penetration force as F (this penetration force is the maximum penetration force of the device), the penetration speed as V, and the penetration stroke as L. Since the working efficiency of the system hydraulic pump station is constant, without considering the energy loss during the energy transfer process and the weights of structures such as pulleys, the product of the penetration force and the penetration speed of the device is always equal to FV. Based on this, analyze the penetration force and penetration speed in each state. In this first stage, i.e., the first gear, other positions are fixed, and the acting force acts directly on the fixed end of the rope. At this time, the penetration force is F, the penetration speed is V, and the penetration stroke is L.

[0044] Refer to as Figures 2 - 4 , and the specific calculation process is as follows: To describe the motion mode of the pulleys, establish a coordinate system. Let the coordinates of the AI pulley be Or , the coordinates of the AII pulley be , the coordinates of the BI pulley be , the coordinates of the fixed end of the rope be , the initial position coordinates of the clamping manipulator be , in the present invention, the positional relationship between the AI and AII pulleys is , , , .

[0045] Define the ideal thrust of the hydraulic cylinder as , and the speed as . According to this position distribution specification, establish the position matrices of the remaining pulleys, and obtain their relative horizontal position relationships as: The relative vertical position relationships are: The final position matrix for penetration in this stage is: See Figure 3 , 4 for the speeds and force conditions of the rope end and pulleys. Only the fixed end of the rope moves, so the speed of the entire towing rope during the penetration stage: . As analyzed above, without considering the energy loss during the power transmission process, not considering the masses of the rope and pulleys, ignoring the friction of the bearings, and without relative displacement during the rotation of the rope around the pulleys, the tensions at all points in the steel wire rope are the same. At this time, the penetration force of the execution end, i.e., the probe.

[0046] Second gear: As shown in Figures 5 - 7As shown, with other positions fixed, the pulley ends of BI and BII can move up and down, i.e., the B pulley group is in the state of a movable pulley. Among them, the BII pulley group acts as a starting pulley, and BI is a supplementary pulley. At this time, all other pulleys are in the state of fixed pulleys, and the rope connection point E is in a fixed state.

[0047] Refer to as Figure 6 , the final position matrix of the penetration in this stage is obtained with the same calculation idea as the first gear: Through analysis, it is obtained that the BI and BII pulley groups are the force-bearing modules. , other pulleys are in the state of fixed pulleys, which changes the direction of the force at the rope end, and the magnitude of the force and the speed of the rope end remain unchanged. At this time, the rope connection point E is fixed, and the following relationship is obtained , and at this time .

[0048] In the ideal state, without considering the gravity of the pulley groups A, B, C, and D, the output force of the hydraulic cylinder acts directly on the pulley group B, then there is , , , the tension in the steel wire rope is the penetration force at the penetration end , when considering the gravity of the pulley groups, let the gravity of the pulley groups A, B, C, and D be , , , , then there is , , , the tension in the steel wire rope, that is, the penetration force at the penetration end, is .

[0049] Through the first and second gears, it can already be obtained that during the penetration process, if the required penetration force is less than half of the current penetration force, the excess penetration force can be withdrawn to achieve a greater penetration stroke and a higher penetration speed, that is, shift from the first gear to the second gear.

[0050] According to the above idea, continue the calculation. Third gear: The rope connection point E and the BIBII pulley group can move up and down. The stroke of the rope connection point E is L, and the BIBII pulley group can obtain a penetration effect with a stroke of 2L. At this time, there are three force effects in the steel wire rope, the steel wire ropes on both sides of the movable pulley and the rope connection point E. Therefore, the force on the towing rope is F / 3, and the penetration force in this state is F / 3, and the penetration speed is 3V.

[0051] The specific calculation process is as follows: The final position matrix of the penetration in this stage is obtained with the same calculation idea as the previous gear: Through analysis, it is obtained that the connection point E between the BI and BII pulley blocks and the rope is the force-receiving module. , and the other pulleys are in a fixed pulley state, which changes the force direction at the rope end while keeping the force magnitude and the rope-end speed unchanged. The following relationships are obtained , and at this time .

[0052] Under ideal conditions, without considering the gravity of pulley blocks A, B, C, and D, the output force of the hydraulic cylinder acts directly on the connection point E between pulley block B and the rope end. Then, there is , , , and the tension in the steel wire rope, i.e., the penetration force at the penetration end, is . When considering the gravity of the pulley block, there is , , , and the tension in the steel wire rope, i.e., the penetration force at the penetration end, is .

[0053] Fourth gear: The two groups of pulley blocks BIBII and DIDII can move up and down. The connection points E between the other pulley blocks and the rope are all in a fixed state. The B pulley block is in a movable pulley state. Among them, the BII and DII pulley blocks act as starting pulleys, and BI and DI are supplementary pulleys. At this time, the two movable pulleys undergo displacements. Then, according to the relevant theory of movable pulleys, the penetration stroke at this time should be 4L, and there are four force effects. Therefore, the force on the steel wire rope should be one-fourth of the original, that is, F / 4. According to the constant working efficiency calculation, the penetration speed at the end is 4V.

[0054] The B and D pulley blocks are the force-receiving modules. Then , and the other pulleys are in a fixed pulley state, which changes the force direction at the rope end while keeping the force magnitude and the rope-end speed unchanged. At this time, the rope end is fixed, and the upper side of the rightmost end of the pulley assembly is the fixed pulley GI, and the lower side is the fixed pulley GII. The following relationships are obtained , and at this time .

[0055] Under ideal conditions, without considering the gravity of pulley blocks A, B, C, and D, the output force of the hydraulic cylinder acts directly on pulley blocks B and C. The tension in the steel wire rope, i.e., the penetration force at the penetration end, is ; when considering the gravity of the pulley block, the tension in the steel wire rope and the penetration force at the penetration end are .

[0056] And so on, the pulleys A to D can be continuously replaced as movable pulleys or fixed pulley states to adjust the ratio of the speed driven by the driving device to the penetration speed at the output end, and reduce the redundant penetration force to improve the working efficiency of the sounding task. See Figures 14 - 22, and so on, the working stages of larger penetration strokes from the fifth gear to the eighth gear can be obtained. Here, the switching between different stages is called "gear shifting".

[0057] In this embodiment, eight gears are selected for illustration. Of course, other numbers of gears can also be set according to actual situations. For the obtained gear selection table, see Table 1.

[0058] Table 1 Gear Selection Table Note: It should be noted that the masses of the pulleys in the present invention are all the same, that is , represents the weight of the overall pulley structure composed of AI and AII, Similarly, and .

[0059] Penetration force is the weight of the tonnage level. Compared with the mass of the pulley, the penetration force can also be ignored. For the simplified gear selection table, see Table 2.

[0060] Table 2 Simplified Gear Selection Table The seabed-based in-situ detection system further includes a control system. The control system includes a memory, in which the gear selection table and the gear-shifting penetration resistance formula are stored. During operation, the data of the soil layer detected by the probe is brought into the gear-shifting penetration resistance formula to obtain the gear-shifting penetration resistance, and the gear-shifting penetration resistance is compared with the gear selection table, querying the gear selection table, and the gear is selected according to the selection principle that the penetration force in the gear is closest to the penetration component and greater than the gear-shifting penetration resistance.

[0061] For example, the maximum penetration force F 0 of this device is taken as an example of 2.5t for illustration. Assuming that the properties of the existing shallow seabed soil layer in a certain sea area are known, the ultimate bearing capacity of the surface soil layer is obtained, that is, the required penetration resistance is , select to query the gear selection table and select the fifth gear for the first penetration.

[0062] According to the data obtained from the first penetration stroke, calculate the gear-shifting penetration resistance, judge whether gear shifting is required for the next penetration stroke, and select which gear to shift to according to the gear selection table. Repeat this step to complete the penetration work.

[0063] The above-described embodiments of the present invention do not constitute a limitation to the protection scope of the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the claims of the present invention.

Claims

1. The seabed in-situ detection system based on force-distance adaptive adjustment is characterized by: The seabed base in-situ detection system includes a plurality of gears, which are set from 1 to n gears according to the penetration force in the gear from low to high, n>1, and the relationship between the penetration force of the n gears and the relationship between the penetration strokes are formed into a gear selection table for gear selection; The seabed-based in-situ detection system method comprises the following steps: Step S1, first penetration; Step S2, calculating the gear shift penetration resistance according to the data detected during the previous penetration step, comparing the gear shift penetration resistance with the penetration force in the gear selection table, and selecting a suitable gear in the gear selection table for the second penetration according to the principle that the penetration force is greater than the penetration resistance; Repeat step S2 to complete the gear selection and penetration of the 3rd to mth penetrations in sequence, where m>3.

2. The seabed in-situ detection system based on force-distance adaptive adjustment according to claim 1 is characterized in that: In step S1, if the properties of the surface soil layer to be penetrated are known, the initial penetration resistance is calculated, and the gear is selected by querying the gear selection table; if the properties of the surface soil layer to be penetrated are unknown, select gear n.

3. The seabed in-situ detection system based on force-distance adaptive adjustment according to claim 1 is characterized in that: If the first penetration stroke can be completed completely, there is no need to downshift; if the first penetration stroke cannot be completed, downshift is required.

4. The seabed in-situ detection system based on force-distance adaptive adjustment according to claim 1 is characterized in that: In step S2, the detected data are the cone tip resistance and the side friction resistance, and the data are substituted into the gear shift penetration resistance formula to obtain the gear shift penetration resistance; Among them, the gear shift penetration resistance formula is: Where: ——The maximum total resistance of the cone tip obtained in the previous penetration stroke; ——Cumulative total sidewall friction times; ——is a constant, ranging from 1.05 to 1.2; ——diameter of probe rod; ——The penetration depth of the probe in the same uniform soil mass; ——the base area of ​​the probe cone; ——The total contact area between the side wall of the probe and the soil; q c —— cone tip resistance; q ci —— i Moment cone tip resistance; p - number of tests; f s ——Lateral friction resistance.

5. The seabed in-situ detection system based on force-distance adaptive adjustment according to claim 1 is characterized in that: The penetration force of low gear is large and the penetration stroke is small, while the penetration force of high gear is small and the penetration stroke is large; during the change from gear 1 to gear n, the penetration force gradually decreases and the penetration stroke gradually increases.

6. The seabed in-situ detection system based on force-distance adaptive adjustment according to claim 1 is characterized in that: The gear selection judgment rule is that the penetration force corresponding to the gear in the gear selection table is closest to the gear shift penetration resistance and is greater than the gear shift penetration resistance.

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