Intelligent oil containment boom mechanical arm device and control method thereof

Abstract

The invention relates to an intelligent oil containment boom mechanical arm device and a control method thereof. The intelligent oil containment boom mechanical arm device comprises a mechanical arm, a hydraulic driving system, a sensing system and a control unit. The mechanical arm comprises a transmission base, a steering stand column, a large arm, a small arm, an overturning head and a tail end grabbing hook assembly. The hydraulic driving system comprises a hydraulic pump station, a proportional reversing electromagnetic valve group and a plurality of execution oil cylinders; the sensing system comprises a gyroscope array and a camera array to form a distributed attitude sensing network and a distributed visual sensing network; the control unit identifies and positions an oil containment boom target based on a sea surface image acquired by the distributed visual perception network, performs motion planning on the mechanical arm, and controls the mechanical arm to move and grab the target; in the target positioning process, posture changes of all parts of the mechanical arm are sensed in real time based on the distributed posture sensing network, and dynamic compensation is conducted on the posture error of the mechanical arm. According to the device, the oil containment boom can be quickly, accurately, reliably and intelligently grabbed, and the laying efficiency and safety of the oil containment boom are improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of oil containment boom mechanical arm of a ship, and particularly relates to an intelligent oil containment boom mechanical arm device of a ship and a control method thereof. BACKGROUND

[0002] In the emergency disposal of offshore oil spill accidents, the rapid deployment and recovery of the oil containment boom is a core link for controlling the spread of pollution. The current mainstream technical solutions can be divided into three categories, but all have significant limitations and are difficult to meet the efficient operation needs in complex sea conditions.

[0003] The artificial deployment of the oil containment boom is a traditional mainstream solution, which relies on large ships to carry multiple operators to complete the segmented connection of the oil containment boom, the throwing of the float and the position adjustment by manpower (Peng Bo et al., Research Progress of Offshore Oil Spill Emergency Disposal Technology, 2019). For example, CN104440919A discloses a float gripping manipulator, which drives the hook to clamp the float through a hydraulic cylinder. Although this solution simplifies the single-point grabbing process, it still requires personnel to control the whole process on the deck, and the function is limited to fixing the float, without solving the problem of overall deployment efficiency. This method is severely restricted by sea conditions and needs to be operated in calm waters with wind speed <20 m / s and wave height <0.5 m, and the single deployment time is more than 2 hours, with significant response lag.

[0004] To improve the automation level, some technologies use remote control boats to carry mechanical structures to achieve semi-automatic operation. For example, CN218022095U discloses a "remote control boat for rapid deployment of oil containment boom", which releases the oil containment boom through a tail winding machine module, inflates the float-type oil containment boom using an air charging and suction machine, and relies on a ship motor to drive the winding drum to release and recover. CN205530181U sets a mechanical arm on the side of the unmanned ship to connect the oil spill recovery device, but the mechanical arm is only used to fix the position of the recovery device and does not participate in the grabbing and posture adjustment of the oil containment boom. Although this solution reduces the risk of personnel exposure, the deployment path completely depends on the heading of the boat body and cannot dynamically correct the shape of the fence.

[0005] To optimize the deployment speed, CN204199260U proposes a "oil containment boom winding device", which embeds a planetary gear reducer and a hydraulic motor in the winding drum cavity to control the winding drum speed and adjust the release speed. This solution realizes the automation of the deployment process, but lacks an end effector, which cannot grab, dock or finely adjust the angle of the end point of the oil containment boom, resulting in the displacement of the fence in the water due to the impact of sea currents and the difficulty in forming a precise U-shaped or V-shaped containment area.

[0006] Specifically, the prior art has the following core problems: insufficient laying precision and dynamic adaptability, a remote control boat winding device (such as CN218022095U) indirectly adjusts the fence position through the boat track, when a complex containment shape needs to be constructed, multiple boats need to be coordinated or the track needs to be repeatedly adjusted, and the response delay is more than 30 minutes; single mechanical function and lack of coordination, the existing technology focuses on optimizing local links, and an artificial auxiliary manipulator (CN104440919A) can only complete single-point clamping, and a remote control boat mechanical arm (CN205530181U) is only used for fixing, and none of them form a full-process closed loop of "recognition-positioning-grasping-compensation"; manual operation has safety hazards, even if the scheme (such as CN205530181U) has a high degree of automation, the initial connection of the oil containment boom and the ship, the end fixing and the abnormal handling still need to be completed manually, and in severe sea conditions with a wave height of more than 1.5 m, the risk rate of the operator falling into the water is 38%; lack of posture compensation and environmental robustness, a traditional mechanical arm mainly uses a single gyroscope for posture correction, when the boat body rolls ± 15°, the end positioning error is more than 32 cm, and the hydraulic system response delay is more than 100 ms, which cannot offset the wave disturbance in real time, resulting in a linear increase in the alignment deviation of the grappling hook and the target object with the wave height.

[0007] The above technical bottlenecks result in that the existing scheme has a grasping success rate of less than 50% in a 3-level sea state (wave height ≤ 1.5 m), the oil containment boom laying efficiency is only 1 / 3 of manual operation, and it is difficult to meet the actual combat needs of unmanned emergency. Therefore, developing an oil containment boom boat mechanical arm device with distributed posture sensing, real-time dynamic compensation and intelligent grasping function has become the key to breaking through the limitations of the existing technology. SUMMARY

[0008] The purpose of the present application is to provide an intelligent oil containment boom boat mechanical arm device and a control method thereof, which can quickly, accurately and reliably grasp the oil containment boom, and improve the efficiency and safety of the oil containment boom laying.

[0009] In order to realize the technical scheme adopted by the present application, an intelligent oil containment boom boat mechanical arm device is provided, which comprises a mechanical arm, a hydraulic drive system, a sensing system and a control unit.

[0010] The mechanical arm comprises a transmission base, a steering column, a large arm, a small arm, a turnover head and a terminal grappling hook assembly connected in sequence.

[0011] The hydraulic drive system comprises a hydraulic pump station, a proportional reversing electromagnetic valve group and a plurality of execution oil cylinders for providing power for the mechanical arm; the plurality of execution oil cylinders comprises a column driving oil cylinder, a large arm driving oil cylinder, a small arm driving oil cylinder, a turnover head driving oil cylinder and a grappling hook driving oil cylinder; the hydraulic pump station is connected with the proportional reversing electromagnetic valve group through a hydraulic pipeline, and the proportional reversing electromagnetic valve group is connected with each execution oil cylinder through a hydraulic pipeline, so as to realize the multi-degree-of-freedom movement and grasping of the mechanical arm.

[0012] The perception system comprises a gyroscope array and a camera array, the gyroscope array comprises a plurality of gyroscopes arranged on a transmission base, a steering column, a large arm, a small arm and a flip head respectively to form a distributed attitude perception network to sense the attitude changes of each part of the mechanical arm, and the camera array comprises a plurality of binocular camera groups arranged on the large arm, the small arm and the flip head respectively to form a distributed visual perception network to obtain sea surface images;

[0013] The control unit is electrically connected with the gyroscope array, the camera array and the proportional reversing electromagnetic valve group respectively, the control unit identifies and locates the target to be grabbed based on the sea surface images obtained by the distributed visual perception network, plans the movement of the mechanical arm, and then controls the movement of the mechanical arm and grabs the target by regulating the proportional reversing electromagnetic valve group; in the target positioning process, the attitude changes of each part of the mechanical arm caused by the surge of the boat body are sensed in real time based on the distributed attitude perception network, and the pose error of the mechanical arm is dynamically compensated.

[0014] Further, the transmission base is composed of a flange base and a gear box arranged thereon; the gear box is fixedly installed on the deck of the boat body through the flange base at the bottom, and the gear box cooperates with the column driving oil cylinder and the transmission gear at the bottom of the steering column through the internal rack and pinion transmission assembly of the gear box to drive the horizontal rotation of the steering column under the driving of the column driving oil cylinder.

[0015] Further, the large arm is rotatably connected with the steering column at the rear end of the large arm, and the small arm is rotatably connected with the large arm at the front end of the small arm; the flip head comprises a first connecting rod, a second connecting rod and a grab hook connecting seat, the first connecting rod is rotatably connected with the front part of the small arm at the rear end of the first connecting rod, the first connecting rod is rotatably connected with the rear end of the second connecting rod at the front end of the first connecting rod, and the front and rear ends of the grab hook connecting seat are rotatably connected with the front end of the second connecting rod and the front end of the small arm respectively; the end grab hook assembly comprises a grab hook rotating hydraulic motor, a grab hook support and two grab hooks, the grab hook support is installed on the grab hook connecting seat through the grab hook rotating hydraulic motor, and the two grab hooks are oppositely arranged and rotatably connected with the grab hook support respectively; the hydraulic pump station is connected with the grab hook rotating hydraulic motor through the hydraulic pipeline and the proportional reversing electromagnetic valve group to drive the rotation of the grab hook rotating hydraulic motor.

[0016] The large arm driving oil cylinder is installed between the steering column and the large arm to drive the rotation of the large arm relative to the steering column; the small arm driving oil cylinder is installed between the large arm and the small arm to drive the rotation of the small arm relative to the large arm; the flip head driving oil cylinder is installed between the small arm and the flip head to drive the rotation of the flip head relative to the small arm; and the grab hook driving oil cylinder is installed between the two grab hooks to drive the opening and closing of the two grab hooks to perform the grabbing action.

[0017] Further, the large arm and the small arm are both hollow structural members of lightweight design; the rear end of the cylinder body of the large arm driving oil cylinder is rotationally connected with the lower end of the steering column, and the front end of the telescopic rod of the large arm driving oil cylinder is rotationally connected with the rear part of the large arm; the rear end of the cylinder body of the small arm driving oil cylinder is rotationally connected with the middle part of the large arm, and the front end of the telescopic rod of the small arm driving oil cylinder is rotationally connected with the rear part of the small arm; the rear end of the cylinder body of the turnover head driving oil cylinder is rotationally connected with the middle-rear part of the small arm, and the front end of the telescopic rod of the turnover head driving oil cylinder is rotationally connected at the rotationally connected joint of the first connecting rod and the second connecting rod.

[0018] Further, the large arm is rotationally connected with the steering column at a pitch angle ranging from 0 to 90 degrees; the small arm is rotationally connected with the large arm at a pitch angle ranging from 0 to 60 degrees; and the turnover head is rotationally connected with the small arm at a pitch angle ranging from 0 to 50 degrees.

[0019] Further, a pressure sensor is arranged on the grab hook of the terminal grab hook assembly, and the control unit is electrically connected with the pressure sensor, so as to detect the force borne by the grab hook through the pressure sensor and regulate the size of the grabbing force.

[0020] Further, the control unit comprises:

[0021] A power module is arranged for converting input electric energy into electric power of different voltage levels and supplying power to each electric component and module in the device;

[0022] A signal receiving module is arranged for supporting multiple communication protocols, receiving data acquired by the gyroscope, the binocular camera and the pressure sensor arranged on the grab hook of the terminal grab hook assembly, and receiving control instructions sent by a wireless remote controller;

[0023] A data processing module is arranged for processing, calculating and analyzing the data received by the signal receiving module and then outputting corresponding control instructions to the signal output module;

[0024] A signal output module is arranged for outputting control signals to each proportional reversing electromagnetic valve, so as to control the movement of the mechanical arm and the execution of the grabbing operation.

[0025] The application further provides a control method of the intelligent oil containment boom boat mechanical arm device, comprising:

[0026] S1, system parameter calibration; a global coordinate system is set with the center of mass of the boat body as the origin , and a boat body coordinate system attitude angle is defined according to the global coordinate system , the attitude angles of the boat body around the x, y, z axes are measured by gyroscopes on the steering column and converted into an attitude angle vector; a mechanical arm base coordinate system is set with a set position on the transmission base as the origin, and the state of each joint motion chain of the mechanical arm is defined in the mechanical arm base coordinate system, and each joint state vector is measured by the gyroscopes on each joint of the mechanical arm and is used to detect and feedback the motion state of each joint of the mechanical arm; a preset recovery position of the mechanical arm is calibrated; an end effector coordinate system is set according to the attitude position and size information of the mechanical arm; the attitude angle of the boat body coordinate system is defined; each gyroscope in the distributed attitude perception network is self-calibrated and initialized;

[0027] S2, target recognition and positioning; a plurality of binocular cameras in the distributed visual perception network scan the target, i.e. the floating pontoon of the oil containment boom, on the sea surface, obtain the sea surface image through the binocular cameras, and then recognize the target from the obtained sea surface image through the YOLOv5-SPF model algorithm; the target data recognized by each group of binocular cameras in the distributed visual perception network is processed through a spatio-temporal alignment fusion algorithm to locate the coordinates of the floating pontoon of the oil containment boom ;

[0028] S3, motion planning and attitude compensation; first, a boat body motion disturbance model is established, and then the mechanical arm base offset caused by the change of the boat body attitude is calculated ; then, the end effector error is calculated by fusing the data of the five gyroscopes, which is used for parameter compensation of target trajectory generation; according to the coordinates of the floating pontoon of the oil containment boom and the end effector error , the compensated target coordinates are obtained by fusion, and then the motion of each joint of the mechanical arm is planned; then, the maximum speed of the motion of the mechanical arm is calculated according to the maximum flow of the proportional directional electromagnetic valve, so as to indirectly control the motion speed of each joint of the mechanical arm by controlling the opening of the proportional directional electromagnetic valve in the subsequent process; the data of the five gyroscopes are fused, the Jacobian matrix error propagation model of the kinematic chain of the mechanical arm is established, the inverse kinematics algorithm is adopted to solve each joint, and the required rotation angle of each joint at different times during the process of the end effector reaching the position of the floating pontoon of the oil containment boom is planned; the joint motion angle signal obtained is converted into the opening of the control proportional directional electromagnetic valve through the feedforward-feedback compound control, so as to indirectly control the motion angle of each joint of the mechanical arm; and in the execution process of the hydraulic drive system, the sliding mode control is adopted to suppress the hydraulic disturbance and the load mutation adaptive dynamic adjustment of the hydraulic cylinder motion is adopted; when the end effector reaches above the floating pontoon of the oil containment boom, the mechanical arm and the grab hook are controlled to grab the target downward, and then the target is put back to the preset recovery position in the reverse direction.

[0029] Further, the implementation method of the YOLOv5-SPF model algorithm is as follows:

[0030] 1) Utilizing spatial pyramid pooling for rapid layering Multi-scale pooling is performed on the input feature map Fin to extract multi-scale features;

[0031] 2) Deformable convolutional networks using deformable kernels To improve the detection accuracy of deformed targets by handling non-rigid deformation of the target;

[0032] 3) Utilizing coordinate attention mechanism Attention weighting is applied to the spatial coordinate information of the input feature map Fin to enhance the spatial location features of the target.

[0033] 4) By using the feature concatenation algorithm Concat, the output feature maps of SPPF, DCNv2, and CoordAtt are concatenated along the channel dimension to integrate three features: multi-scale, deformation adaptation, and spatial attention.

[0034] 5) Use the convolutional layer Conv to perform convolution operations on the stitched feature map, adjust the number of channels and integrate the features to obtain the final output feature Fout, which is the bounding box data of the oil boom pontoon.

[0035] Furthermore, during motion planning and attitude compensation, a dynamic coordinate transformation algorithm is used to calculate the offset of the robotic arm base caused by changes in the hull attitude. The calculation formula is:

[0036]

[0037] in, For the rotation tensor, derived from the hull attitude angle generate; This represents the lever vector from the center of mass of the hull to the base of the robotic arm; Measure noise for the gyroscope;

[0038] The end effector error is calculated by fusing data from five gyroscopes. The calculation formula is as follows:

[0039]

[0040] in, Indicates the first The end-position error estimated by each gyroscope Indicates the weighting coefficient. Indicates the first Measurement variance of each gyroscope It is a natural constant. The time decay coefficient, This is the current timestamp;

[0041] Based on the coordinates of the oil boom pontoons and end effector error The target coordinates are obtained after fusion and compensation. The calculation formula is as follows:

[0042]

[0043] Then, the motion planning of each joint of the robotic arm is performed using the fifth-order polynomial method to generate the trajectory from the current position to the compensated target position, the expression of which is:

[0044]

[0045] in, Represents the total time of the trajectory, coefficient Determined by boundary conditions, ;

[0046] The maximum speed of the robotic arm is:

[0047]

[0048] in, Indicates the valve's maximum flow rate. Represents the flow coefficient. Indicates the maximum opening area of ​​the valve. This indicates the maximum pressure difference across the valve. Indicates the density of hydraulic oil. Indicates the effective area of ​​the piston;

[0049] In feedforward-feedback composite control, the controller output signal is represented as:

[0050]

[0051] in, Indicates the trajectory tracking error. The proportional and differential gain matrices;

[0052] Sliding mode control is used to suppress hydraulic disturbances, and its expression is:

[0053]

[0054] in, This represents the final output signal of the sliding mode controller. This represents the gain coefficient in the control law. Indicates the sliding surface. Indicates the slope of the sliding surface. This represents the original trajectory tracking error. express The derivative of Indicates the boundary layer thickness. Represents a saturation function;

[0055] When using adaptive dynamic adjustment of hydraulic cylinder movement based on load mutation, if the oil pressure mutation of the hook drive cylinder exceeds a set threshold, then:

[0056]

[0057] in, This represents the updated proportional gain. Indicates the base proportional gain. Indicates the amount of load change. , This represents the load capacity converted from hydraulic pressure. This represents the initial value of the load force converted from hydraulic pressure. ,in The inner diameter of the hydraulic cylinder. The diameter of the piston rod. The pressure difference between the two chambers of the hydraulic cylinder; This is the adjustment coefficient; This indicates the amount of change in the hull's attitude.

[0058] Compared with existing technologies, the present invention has the following beneficial effects: The present invention provides an intelligent oil boom boom robotic arm device and its control method. Through innovative design of the structure of the robotic arm, hydraulic drive system, sensing system and control unit, and combined with software implementation of a control method based on autonomous identification and positioning and dynamic attitude compensation, it can achieve rapid, accurate and reliable intelligent grasping of oil booms, replacing manual deck operation and realizing unmanned deployment. It not only greatly shortens the time for grasping and deploying oil booms and effectively improves the efficiency of oil boom deployment, but also effectively improves work safety. It can also adapt to continuous operation in sea state 3. Therefore, it has strong practicality and broad application prospects. Attached Figure Description

[0059] Figure 1 This is a schematic diagram of the structure of the intelligent oil boom boom robotic arm device provided in an embodiment of the present invention. Figure 1 ;

[0060] Figure 2 This is a schematic diagram of the structure of the intelligent oil boom boom robotic arm device provided in an embodiment of the present invention. Figure 2 ;

[0061] Figure 3 This is a schematic diagram of the hydraulic drive system in an embodiment of the present invention;

[0062] Figure 4 This is a flowchart illustrating the implementation of the control method for the intelligent oil boom boat robotic arm device provided in this embodiment of the invention.

[0063] In the figure: 1 - transmission base; 2 - steering column; 3 - large arm; 4 - small arm; 5 - turning head; 6 - end grapple assembly; 7 - column drive cylinder; 8 - large arm drive cylinder; 9 - small arm drive cylinder; 10 - turning head drive cylinder; 11 - grapple drive cylinder; 12 - first gyroscope; 13 - second gyroscope; 14 - third gyroscope; 15 - fourth gyroscope; 16 - fifth gyroscope; 17 - first set of binocular cameras; 18 - second set of binocular cameras; 19 - third set of binocular cameras; 20 - flange base; 21 - gear box; 22 - first connecting rod; 23 - second connecting rod; 24 - grapple connecting seat; 25 - grapple rotating hydraulic motor; 26 - grapple support; 27 - grapple; 28 - oil storage tank; 29 - hydraulic pump; 30 - pressure regulating valve; 31 - hydraulic distributor; 32 - oil pressure sensor; 33 - electromagnetic pressure regulating valve; V1 - first proportional reversing electromagnetic valve; V2 - second proportional reversing electromagnetic valve; V3 - third proportional reversing electromagnetic valve; V4 - fourth proportional reversing electromagnetic valve; V5 - fifth proportional reversing electromagnetic valve; V6 - sixth proportional reversing electromagnetic valve. DETAILED DESCRIPTION

[0064] The application will be further described below in conjunction with the accompanying drawings and examples.

[0065] It should be noted that the following detailed description is exemplary in nature and is intended to provide further description of the application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0066] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0067] As shown in FIG. 1, the present embodiment provides an intelligent oil containment boom boat mechanical arm device, which comprises a mechanical arm, a hydraulic drive system, a sensing system, and a control unit. Figures 1-2

[0068] The mechanical arm comprises a transmission base 1, a steering column 2, a large arm 3, a small arm 4, a turning head 5, and an end grapple assembly 6 connected in sequence.

[0069] ​The hydraulic drive system includes a hydraulic pump station, a proportional reversing solenoid valve group and a plurality of execution oil cylinders for providing power to the mechanical arm. The plurality of execution oil cylinders includes a column drive oil cylinder 7, a boom drive oil cylinder 8, a small arm drive oil cylinder 9, a turnover head drive oil cylinder 10, a grab hook rotating hydraulic motor 25 and a grab hook drive oil cylinder 11, the hydraulic pump station is connected with the proportional reversing solenoid valve group through a hydraulic pipeline, and each execution oil cylinder is connected with the proportional reversing solenoid valve group through a hydraulic pipeline, so as to realize multi-degree-of-freedom motion and grabbing of the mechanical arm.

[0070] Figure 3 It is the principle diagram of the hydraulic drive system in the embodiment. As shown in the figure, Figure 3 In the embodiment, the hydraulic pump station is composed of an oil tank 28, a hydraulic pump 29, a pressure regulating valve 30 and a hydraulic distributor 31; the hydraulic pump station is connected with the column drive oil cylinder 7, the boom drive oil cylinder 8, the small arm drive oil cylinder 9, the turnover head drive oil cylinder 10, the grab hook rotating hydraulic motor 25 and the grab hook drive oil cylinder 11 through proportional reversing solenoid valves V1, V2, V3, V4, V5, V6 and corresponding hydraulic pipelines, so as to drive the corresponding oil cylinders to work by regulating the opening degree of each proportional reversing solenoid valve group. Among them, an oil pressure sensor 32 and an electromagnetic pressure regulating valve 33 are arranged on the hydraulic pipeline between the proportional reversing solenoid valve V6 and the grab hook drive oil cylinder 11, so as to detect and regulate the oil pressure of the grab hook drive oil cylinder 11.

[0071] The perception system includes a gyroscope array and a camera array, the gyroscope array includes a plurality of gyroscopes 12, 13, 14, 15, 16 arranged on the transmission base, the steering column 2, the boom 3, the small arm 4 and the turnover head 5 respectively, so as to form a distributed attitude perception network to sense the attitude change of each part of the mechanical arm, and the camera array includes a plurality of binocular cameras 17, 18, 19 arranged on the boom 3, the small arm 4 and the turnover head 5 respectively, so as to form a distributed visual perception network to obtain sea surface images.

[0072] The control unit is electrically connected with the gyroscope array, the camera array and the proportional reversing solenoid valve group respectively, the control unit identifies and locates the target to be grabbed based on the sea surface images obtained by the distributed visual perception network, plans the motion of the mechanical arm, and then controls the motion of the mechanical arm and grabs the target by regulating the proportional reversing solenoid valve group; in the target positioning process, the attitude change of each part of the mechanical arm caused by the surge of the boat body is sensed in real time based on the distributed attitude perception network, and then the pose error of the mechanical arm is dynamically compensated.

[0073] The transmission base 1 is composed of a flange base 20 and a gear box 21 arranged on the flange base 20. The gear box 21 is fixedly installed on the deck of the boat body through the flange base 20 at the bottom, and is matched with the vertical column driving oil cylinder 7 and the transmission gear at the bottom of the steering vertical column 2 through the internal rack and pinion transmission assembly of the gear box 21, so as to drive the steering vertical column to horizontally rotate under the driving of the vertical column driving oil cylinder.

[0074] The upper end of the steering vertical column 2 is rotationally connected with the rear end of the large arm 3, and the front end of the large arm 3 is rotationally connected with the rear end of the small arm 4. The turnover head 5 includes a first connecting rod 22 (in this embodiment, an arc-shaped structure), a second connecting rod 23 and a grab hook connecting seat 24. The rear end of the first connecting rod 22 is rotationally connected with the front part of the small arm 4, the front end of the first connecting rod 22 is rotationally connected with the rear end of the second connecting rod 23, and the front and rear ends of the grab hook connecting seat 24 are respectively rotationally connected with the front end of the second connecting rod 23 and the front end of the small arm 4. The end grab hook assembly 6 includes a grab hook rotating hydraulic motor 25, a grab hook support 26 and two grab hooks 27. The grab hook support 26 is installed on the grab hook connecting seat 24 through the grab hook rotating hydraulic motor 25, and the two grab hooks 27 are oppositely arranged and are respectively rotationally connected with the grab hook support 26. The hydraulic pump station is connected with the grab hook rotating hydraulic motor 25 through the hydraulic pipeline and the proportional reversing electromagnetic valve group, so as to drive the rotation of the grab hook rotating hydraulic motor 25.

[0075] The large arm driving oil cylinder 8 is installed between the steering vertical column 2 and the large arm 3, so as to drive the large arm to rotate relative to the steering vertical column. The small arm driving oil cylinder 9 is installed between the large arm 3 and the small arm 4, so as to drive the small arm to rotate relative to the large arm. The turnover head driving oil cylinder 10 is installed between the small arm 4 and the turnover head 5, so as to drive the turnover head to rotate relative to the small arm. The grab hook driving oil cylinder 11 is installed between the two grab hooks, so as to drive the two grab hooks 27 to open and close to perform the grabbing action.

[0076] In this embodiment, the large arm 3 and the small arm 4 are both hollow structural members of lightweight design. The rear end of the cylinder body of the large arm driving oil cylinder 8 is rotationally connected with the lower end of the steering vertical column 2, and the front end of the telescopic rod of the large arm driving oil cylinder 8 is rotationally connected with the rear part of the large arm 3. The rear end of the cylinder body of the small arm driving oil cylinder 9 is rotationally connected with the middle part of the large arm 3, and the front end of the telescopic rod of the small arm driving oil cylinder 9 is rotationally connected with the rear part of the small arm 4. The rear end of the cylinder body of the turnover head driving oil cylinder 10 is rotationally connected with the middle and rear part of the small arm 4, and the front end of the telescopic rod of the turnover head driving oil cylinder 10 is rotationally connected at the rotation connection joint of the first connecting rod 22 and the second connecting rod 23.

[0077] Through the above design, the device can realize that the pitch angle range of the large arm rotating relative to the steering vertical column is 0-90°, the pitch angle range of the small arm rotating relative to the large arm is 0-60°, and the pitch angle range of the turnover head rotating relative to the small arm is 0-50°.

[0078] In this embodiment, a pressure sensor is provided on the hook of the end gripper assembly 6, and the control unit is electrically connected to the pressure sensor to detect the force on the hook and adjust the magnitude of the gripping force.

[0079] In this embodiment, the control unit includes:

[0080] 1) Power module, used to convert input electrical energy into power of different voltage levels and to power various electrical components and modules in the device;

[0081] 2) Signal receiving module, which supports multiple communication protocols, is used to receive data from the gyroscope, binocular camera and pressure sensor on the end effector, as well as control commands sent by the wireless remote controller.

[0082] 3) Data processing module, used to process, calculate and analyze the data received by the signal receiving module, and then output corresponding control commands to the signal output module;

[0083] 4) Signal output module, used to output control signals to each proportional solenoid valve to control the movement of the robotic arm and perform grasping operations.

[0084] like Figure 4 As shown, this embodiment also provides a control method for the above-mentioned intelligent oil boom boat robotic arm device, including:

[0085] S1, System Parameter Calibration

[0086] 1) After the robotic arm is installed on the ship, set the global coordinate system with the ship's center of mass as the origin. The attitude angles of the hull coordinate system are defined according to the global coordinate system. The attitude angles of the hull around the x, y, and z axes (usually corresponding to roll, pitch, and yaw) are measured by the gyroscope on the transmission base and converted into attitude angle vectors, which serve as feedback for subsequent attitude compensation.

[0087] 2) The position is set on the transmission base (generally the center position of the flange base, and...). via lever arm vector (Associated calculations) The robot arm base coordinate system is set as the origin, and the motion chain state of each joint of the robot arm is defined in the robot arm base coordinate system. The angular velocity and rotation angle of each joint are measured by the gyroscope on each joint of the robot arm, which is used to detect and provide feedback on the motion state of each joint of the robot arm.

[0088] 3) Set the preset recovery pose of the mechanical arm and calibrate it. Specifically, set the mechanical arm at a predetermined pose (referred to as zero pose, set the joint angle θ = 0° at this pose), capture the deck marker point (which is also used as the preset recovery position) through the camera, calculate the recovery pose through the hand-eye calibration algorithm, specifically, through the rotation matrix of the camera coordinate system relative to the mechanical arm end coordinate system (hand-eye rotation) and the translation vector of the camera coordinate system relative to the mechanical arm end coordinate system (hand-eye translation), in combination with the minimization of the projection error + regularization, the transformation matrix of the camera relative to the mechanical arm end is solved, and the preset recovery pose calibration (i.e. accurate mapping of "the target position seen by the camera" and "the position the mechanical arm needs to move") is realized.

[0089] 4) Set the end effector coordinate system according to the pose position and size information (arm span) of the mechanical arm.

[0090] 5) Define the boat body coordinate system attitude angle. After the coordinates are determined, each gyroscope in the distributed attitude perception network is self-calibrated and initialized.

[0091] S2, target recognition and positioning

[0092] Three groups of 5 million pixel binocular cameras (6 cameras in total) are used to build a distributed visual perception network, which expands the effective field of view angle to 120° through a multi-view geometry network, and eliminates the blind area of a single camera.

[0093] After the system is powered on, the system begins to initialize and self-check. After the self-check is normal, it begins to enter the designated routine scanning and identification program. The mechanical arm begins to swing in all directions according to the predetermined program. The three groups of binocular cameras in the distributed visual perception network scan the targets on the sea surface, i.e. the floating barrels of the oil containment boom, obtain the sea surface image through the binocular cameras, and then identify the target from the obtained sea surface image through the YOLOv5-SPF model algorithm. The implementation method of the YOLOv5-SPF model algorithm is:

[0094] 1) Use the spatial pyramid pooling fast layer to perform multi-scale pooling (such as 1x1, 2x2, 3x3 pooling) on the input feature map Fin, and extract multi-scale features (adapt to different sizes of targets, such as different perspective sizes of floating barrels);

[0095] 2) Use the deformable convolution network with a deformable convolution kernel (the position of the convolution kernel adjusts with the target shape) to handle the non-rigid deformation of the target (such as the inclination and rotation of the floating barrel in the water), in order to improve the detection accuracy of the deformed target;

[0096] 3) Use the coordinate attention mechanism The spatial coordinate information (x / y axis) of the input feature map Fin is attention weighted to enhance the spatial position features of the target (such as the edge and corner point of the buoy) and reduce background interference.

[0097] 4) The output feature maps of SPPF, DCNv2, and CoordAtt are concatenated along the channel dimension by the feature concatenation algorithm Concat (e.g., C1 channels for SPPF output, C2 channels for DCNv2 output, and C3 channels for CoordAtt output, which are concatenated into C1+C2+C3 channels), to fuse multi-scale, deformation-adaptive, and spatial attention features.

[0098] 5) The concatenated feature map is convolved by the convolution layer Conv to adjust the channel number and integrate the features, obtaining the final output feature Fout, which is the bounding box data of the boom buoy.

[0099] One of the innovations of this method is the application of the YOLOv5-SPF model algorithm, which solves the detection accuracy problem of traditional YOLOv5 in multi-scale targets, deformed targets, and complex backgrounds, improving the detection accuracy (mAP@0.5 of buoy detection reaches 96.7%) and inference speed (42ms / frame) of targets such as buoys.

[0100] Then, the target data identified by each group of binocular cameras in the distributed visual perception network is processed by a spatio-temporal alignment fusion algorithm to locate the coordinates of the boom buoy . Specifically, first define the view index i, three groups of binocular cameras, and a total of six cameras, each corresponding to a view i; then use the Triangulate(ui,vi) triangulation function combined with the parallax of the binocular camera to calculate the three-dimensional coordinates X target of the boom buoy. Next, the motion planning algorithm and the dynamic compensation algorithm of the gyroscope are fused to accurately lock the target and prepare to grab the boom buoy.

[0101] S3, Motion Planning and Attitude Compensation

[0102] Motion planning and attitude compensation work together to compensate and plan motion according to the changes in the attitude angle of the boat body.

[0103] 1) According to the motion attitude compensation calculation of the boat body affected by the sea waves, the feedforward compensation for motion planning is calculated. First, establish a boat body motion disturbance model, then use a dynamic coordinate transformation algorithm to calculate the base offset of the robot arm caused by the change in the attitude of the boat body , the calculation formula is:

[0104]

[0105] where, is the rotation tensor, which is calculated by the attitude angle of the boat body generated; represents the lever arm vector from the center of the boat body to the base of the mechanical arm (mechanical fixed parameters); is the gyroscope measurement noise.

[0106] Then use five gyroscope data fusion to calculate the end effector error , which is used for parameter compensation for target trajectory generation; its calculation formula is:

[0107]

[0108] wherein, represents the end position error estimated by the th gyroscope, represents the weight coefficient, which comprehensively measures the reliability and data timeliness of the gyroscope, and determines the contribution size of the end position error estimated by the th gyroscope to the fusion result, represents the measurement variance of the th gyroscope (reflecting the reliability of the sensor), is a natural constant, is a time decay coefficient (typical value 0.1~0.5), is the current timestamp (seconds).

[0109] According to the coordinates of the oil containment boom buoy and the end effector error , the compensated target coordinates are obtained by fusion, and the calculation formula is:

[0110]

[0111] Then use the quintic polynomial method to plan the motion of each joint of the mechanical arm, generate the trajectory from the current position to the compensated target position, and the expression is:

[0112]

[0113] wherein, represents the total time of the trajectory (generally specified as 15 seconds), and the coefficient ( ) is determined by the boundary conditions:

[0114] Starting / ending position: , ;

[0115] Starting / ending velocity: , ;

[0116] Starting / ending acceleration: , .

[0117] Next, the maximum speed of the robotic arm is calculated based on the maximum flow rate of the proportional solenoid valve, so that the movement speed of each joint of the robotic arm can be indirectly controlled by controlling the opening of the proportional solenoid valve in the future.

[0118] The maximum speed of the robotic arm is:

[0119]

[0120] in, This indicates the valve's maximum flow rate (m³ / s). Indicates the flow coefficient (determined by valve structure). This indicates the maximum opening area of ​​the valve (m²). This indicates the maximum pressure difference (Pa) across the valve. This indicates the density of hydraulic oil (kg / m³). This represents the effective area of ​​the piston (m²).

[0121] By integrating data from five gyroscopes, and establishing a Jacobian matrix error propagation model for the robotic arm's kinematics chain, an inverse kinematics algorithm (Levenberg-Marquardt algorithm) is used to perform inverse kinematics calculations on each joint, thus planning the required rotation angle of each joint at different times during the process of the end effector reaching the location of the oil boom float.

[0122] Solve for joint angles :

[0123] in, Represents the positive kinematic function. Jacobian matrix ( ), This is the damping coefficient (to prevent singularities).

[0124] The obtained joint motion angle signals are converted into the opening degree of the proportional directional solenoid valve through feedforward-feedback composite control, thereby indirectly controlling the motion angles of each joint of the robotic arm. In feedforward-feedback composite control, the controller output signal is represented as:

[0125]

[0126] Among them, feedback items:

[0127] Indicates trajectory tracking error;

[0128] Let be the proportional and differential gain matrices.

[0129] Feedforward term:

[0130] For end effector error.

[0131] During the hydraulic drive system execution process, the hydraulic disturbance is suppressed by using a sliding mode control, and the hydraulic cylinder movement is dynamically adjusted by using a load mutation self-adaptive control.

[0132] The hydraulic disturbance is suppressed by using a sliding mode control, and the expression is:

[0133]

[0134] wherein, represents the final output signal of the sliding mode controller, represents the gain coefficient in the control law, represents the sliding surface, represents the slope of the sliding surface (>0), represents the original trajectory tracking error, represents the derivative of represents the derivative of represents the boundary layer thickness (to suppress chattering), represents the saturation function.

[0135] When the hydraulic cylinder movement is dynamically adjusted by using a load mutation self-adaptive control, when the oil pressure of the grab hook driving cylinder (measured by the oil pressure sensor installed on the front side of the grab hook driving cylinder) changes by more than a set threshold value, there is:

[0136]

[0137] wherein, represents the updated proportional gain, represents the basic proportional gain (pre-set initial value to ensure control stability under normal circumstances), represents the load change (N), , represents the oil pressure converted load force, represents the initial value of the oil pressure converted load force, wherein is the inner diameter of the oil cylinder (m), is the diameter of the piston rod (m), is the pressure difference between the two chambers of the oil cylinder (Pa); is the adjustment coefficient (unit: 1 / (N·rad), wherein N is the unit of force, and rad is the unit of radian); represents the amount of change in the boat body attitude (rad).

[0138] When the end effector reaches above the boom buoy of the boom, the mechanical arm and the grab hook are controlled to grab the target downward, and then the target is placed back to the pre-set recovery position in the reverse direction.

[0139] The device has been verified in multiple simulation exercises in multiple sea areas. It is suitable for continuous operation in three-level sea conditions and shows the development direction of intelligent marine emergency equipment. In actual operation, the system shows excellent environmental adaptability and control accuracy. Even in complex sea conditions with gusts up to level 3 and wave height exceeding 0.5 meters, it can still complete the task of grabbing and docking the oil containment boom. In the multi-machine cooperative operation scene, the state synchronization between devices is realized through high anti-interference frequency hopping communication protocol, further improving the efficiency of joint operation. The latest test shows that the system can run continuously for 24 hours without failure in the offshore environment with high salt mist concentration, and the protection level of the key components reaches IP68. Through reinforcement learning algorithm to iteratively optimize the grabbing strategy, the system has the ability to adapt to different specifications of oil containment boom. The success rate of the hydraulic mechanical arm in completing the multi-angle and multi-pose docking task in the dynamic environment has increased to 98.5%. In the anti-interference test, the device continuously operates in a strong electromagnetic interference environment for two hours, with a communication packet loss rate of less than 0.1%, and the data link stability is significantly enhanced. The system's startup performance in low-temperature environments has also been verified, and the hydraulic oil flowability remains stable at -10℃, and the actuator response speed does not decrease significantly.

[0140] The above is only the preferred embodiment of the present application, not other forms of the present application, any skilled in the art may use the above disclosed technical content to change or modify equivalent embodiments. However, any simple modification, equivalent change and modification of the above embodiments without departing from the technical solution of the present application, according to the technical essence of the present application, still belongs to the protection scope of the technical solution of the present application.

Claims

1. A smart oil boom boom robotic arm device, characterized in that, Includes robotic arm, hydraulic drive system, sensing system and control unit; The robotic arm includes a transmission base, a steering column, a large arm, a small arm, a flipping head, and an end gripper assembly connected in sequence. The hydraulic drive system includes a hydraulic pump station, a proportional reversing solenoid valve group, and multiple actuator cylinders to provide power to the robotic arm. The multiple actuator cylinders include a column drive cylinder, a boom drive cylinder, a forearm drive cylinder, a tilting head drive cylinder, and a hook drive cylinder. The hydraulic pump station is connected to the proportional reversing solenoid valve group through hydraulic lines, and the proportional reversing solenoid valve group is connected to each actuator cylinder through hydraulic lines to realize multi-degree-of-freedom movement and grasping of the robotic arm. The sensing system includes a gyroscope array and a camera array. The gyroscope array includes multiple gyroscopes respectively installed on the transmission base, steering column, upper arm, lower arm and tilting head to form a distributed attitude sensing network to sense the attitude changes of each part of the robotic arm. The camera array includes multiple sets of binocular cameras respectively installed on the upper arm, lower arm and tilting head to form a distributed visual sensing network to acquire sea surface images. The control unit is electrically connected to the gyroscope array, camera array, and proportional solenoid valve group, respectively. The control unit identifies and locates the target to be grasped based on the sea surface image acquired by the distributed visual perception network, performs motion planning for the robotic arm, and then controls the movement of the robotic arm to grasp the target by adjusting the proportional solenoid valve group. During the target positioning process, the control unit senses the attitude changes of various parts of the robotic arm in real time caused by the swaying of the hull due to the wave surge based on the distributed attitude perception network, and then dynamically compensates for the posture error of the robotic arm.

2. The intelligent oil boom boom robotic arm device according to claim 1, characterized in that, The transmission base consists of a flange base and a gearbox mounted thereon. The gearbox is fixedly installed on the deck of the hull via the flange base at the bottom. The gearbox is connected to the column drive cylinder and the transmission gear at the bottom of the steering column via its internal rack and gear transmission assembly, so as to drive the steering column to rotate horizontally under the drive of the column drive cylinder.

3. The intelligent oil boom boom robotic arm device according to claim 1, characterized in that, The upper end of the steering column is rotatably connected to the rear end of the boom, and the front end of the boom is rotatably connected to the rear end of the forearm. The tilting head includes a first link, a second link, and a hook connecting seat. The rear end of the first link is rotatably connected to the front of the forearm, and the front end of the first link is rotatably connected to the rear end of the second link. The front and rear ends of the hook connecting seat are rotatably connected to the front end of the second link and the front end of the forearm, respectively. The end hook assembly includes a hook rotating hydraulic motor, a hook bracket, and two hooks. The hook bracket is mounted on the hook connecting seat via the hook rotating hydraulic motor. The two hooks are arranged opposite each other and rotatably connected to the hook bracket. The hydraulic pump station is connected to the hook rotating hydraulic motor via hydraulic lines and a proportional reversing solenoid valve group to drive its rotation. The boom drive cylinder is installed between the steering column and the boom to drive the boom to rotate relative to the steering column; the forearm drive cylinder is installed between the boom and the forearm to drive the forearm to rotate relative to the boom; the tilting head drive cylinder is installed between the forearm and the tilting head to drive the tilting head to rotate relative to the forearm; the hook drive cylinder is installed between the two hooks to drive the two hooks to open and close to perform the gripping action.

4. The intelligent oil boom boom robotic arm device according to claim 3, characterized in that, Both the boom and forearm are lightweight, hollow-structure components. The rear end of the boom drive cylinder is rotatably connected to the lower end of the steering column, and the front end of the boom drive cylinder's telescopic rod is rotatably connected to the rear of the boom. The rear end of the forearm drive cylinder is rotatably connected to the middle of the boom, and the front end of the forearm drive cylinder's telescopic rod is rotatably connected to the rear of the forearm. The rear end of the tilting head drive cylinder is rotatably connected to the middle and rear of the forearm, and the front end of the tilting head drive cylinder's telescopic rod is rotatably connected to the rotating joint between the first and second connecting rods.

5. The intelligent oil boom boom robotic arm device according to claim 3, characterized in that, The pitch angle range of the upper arm relative to the steering column is 0-90°; the pitch angle range of the lower arm relative to the upper arm is 0-60°; and the pitch angle range of the tilting head relative to the lower arm is 0-50°.

6. The intelligent oil boom boom robotic arm device according to claim 1, characterized in that, The end gripper assembly has a pressure sensor installed on its gripper. The control unit is electrically connected to the pressure sensor to detect the force on the gripper and adjust the gripping force accordingly.

7. The intelligent oil boom boom robotic arm device according to claim 1, characterized in that, The control unit includes: The power module is used to convert input electrical energy into power at different voltage levels and to supply power to various electrical components and modules in the device. The signal receiving module supports multiple communication protocols and is used to receive data from the gyroscope, binocular camera, and pressure sensor on the end effector assembly, as well as control commands sent by the wireless remote controller. The data processing module is used to process, calculate and analyze the data received by the signal receiving module, and then output corresponding control commands to the signal output module. The signal output module is used to output control signals to each proportional solenoid valve to control the movement of the robotic arm and perform grasping operations.

8. The control method for the intelligent oil boom boom robotic arm device according to any one of claims 1-7, characterized in that, include: S1, System parameter calibration; Establish a global coordinate system with the center of mass of the submarine as the origin. The attitude angles of the hull coordinate system are defined according to the global coordinate system. The system measures the hull's attitude angles around the x, y, and z axes using gyroscopes on the steering column and converts them into attitude angle vectors. A robotic arm base coordinate system is established with a set position on the transmission base as the origin. Within this coordinate system, the kinematic chain state of each joint of the robotic arm is defined. The angular velocity and rotation angle of each joint are measured by gyroscopes on each joint, used to detect and provide feedback on the motion state of each joint. The robotic arm's recovery pose is preset and calibrated. The end effector coordinate system is set based on the robotic arm's attitude position and size information. The hull coordinate system attitude angles are defined. Each gyroscope in the distributed attitude perception network performs self-calibration and initialization. S2. Target Recognition and Localization: Multiple binocular cameras in the distributed visual perception network scan the target on the sea surface, namely the oil boom buoys, acquiring sea surface images through the binocular cameras. Then, the YOLOv5-SPF model algorithm is used to identify the target from the acquired sea surface images. The target data identified by each group of binocular cameras in the distributed visual perception network are processed by a spatiotemporal alignment fusion algorithm to locate the coordinates of the oil boom buoys. ; S3. Motion Planning and Attitude Compensation: First, establish a motion disturbance model of the hull, then calculate the offset of the robotic arm base caused by changes in the hull attitude. ; Then, the end effector error is calculated by fusing data from five gyroscopes. Parameter compensation used for target trajectory generation; based on the coordinates of the oil boom buoys. and end effector error The target coordinates are obtained after fusion and compensation. Then, motion planning is performed on each joint of the robotic arm; The maximum speed of the robotic arm is then calculated based on the maximum flow rate of the proportional solenoid valve, so that the movement speed of each joint of the robotic arm can be indirectly controlled by controlling the opening of the proportional solenoid valve in the future. By integrating data from five gyroscopes, a Jacobian matrix error propagation model of the robotic arm's kinematics chain is established. Inverse kinematics algorithms are used to perform inverse kinematics calculations on each joint, planning the required rotation angle of each joint at different times during the process of the end effector reaching the position of the boom float. The obtained joint motion angle signals are converted into control of the opening of the proportional directional solenoid valve through feedforward-feedback composite control, indirectly controlling the motion angle of each joint of the robotic arm. In the hydraulic drive system, sliding mode control is used to suppress hydraulic disturbances and adaptive dynamic adjustment of hydraulic cylinder movement is adopted through load mutation. When the end effector reaches the top of the boom float, the robotic arm and hook are controlled to grab the target downwards, and then move in reverse to place the target back to the preset recovery position.

9. The control method for the intelligent oil boom boat robotic arm device according to claim 8, characterized in that, The implementation method of the YOLOv5-SPF model algorithm is as follows: 1) Utilizing spatial pyramid pooling for rapid layering Multi-scale pooling is performed on the input feature map Fin to extract multi-scale features; 2) Deformable convolutional networks using deformable kernels To improve the detection accuracy of deformed targets by handling non-rigid deformation of the target; 3) Utilizing coordinate attention mechanism Attention weighting is applied to the spatial coordinate information of the input feature map Fin to enhance the spatial location features of the target. 4) By using the feature concatenation algorithm Concat, the output feature maps of SPPF, DCNv2, and CoordAtt are concatenated along the channel dimension to integrate three features: multi-scale, deformation adaptation, and spatial attention. 5) Use the convolutional layer Conv to perform convolution operations on the stitched feature map, adjust the number of channels and integrate the features to obtain the final output feature Fout, which is the bounding box data of the oil boom pontoon.

10. The control method for the intelligent oil boom boom robotic arm device according to claim 8, characterized in that, During motion planning and attitude compensation, a dynamic coordinate transformation algorithm is used to calculate the offset of the robotic arm base caused by changes in the hull attitude. The calculation formula is: in, For the rotation tensor, derived from the hull attitude angle generate; This represents the lever vector from the center of mass of the hull to the base of the robotic arm; Measure noise for the gyroscope; The end effector error is calculated by fusing data from five gyroscopes. The calculation formula is as follows: in, Indicates the first The end-position error estimated by each gyroscope Indicates the weighting coefficient. Indicates the first Measurement variance of each gyroscope It is a natural constant. The time decay coefficient, This is the current timestamp; Based on the coordinates of the oil boom pontoons and end effector error The target coordinates are obtained after fusion and compensation. The calculation formula is as follows: Then, the motion planning of each joint of the robotic arm is performed using the fifth-order polynomial method to generate the trajectory from the current position to the compensated target position, the expression of which is: in, Represents the total time of the trajectory, coefficient Determined by boundary conditions, ; The maximum speed of the robotic arm is: in, Indicates the valve's maximum flow rate. Represents the flow coefficient. Indicates the maximum opening area of ​​the valve. This indicates the maximum pressure difference across the valve. Indicates the density of hydraulic oil. Indicates the effective area of ​​the piston; In feedforward-feedback composite control, the controller output signal is represented as: in, Indicates the trajectory tracking error. The proportional and differential gain matrices; Sliding mode control is used to suppress hydraulic disturbances, and its expression is: in, This represents the final output signal of the sliding mode controller. This represents the gain coefficient in the control law. Indicates the sliding surface. Indicates the slope of the sliding surface. This represents the original trajectory tracking error. express The derivative, Indicates the boundary layer thickness. Represents a saturation function; When using adaptive dynamic adjustment of hydraulic cylinder movement based on load mutation, if the oil pressure mutation of the hook drive cylinder exceeds a set threshold, then: in, This represents the updated proportional gain. Indicates the base proportional gain. Indicates the amount of load change. , This represents the load capacity converted from hydraulic pressure. This represents the initial value of the load force converted from hydraulic pressure. ,in The inner diameter of the hydraulic cylinder. The diameter of the piston rod. The pressure difference between the two chambers of the hydraulic cylinder; This is the adjustment coefficient; This indicates the amount of change in the hull's attitude.

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