A pipe cable guiding and limiting device for an underwater robot and an underwater robot

Abstract

The application discloses a pipe cable guiding and limiting device for an underwater robot, which comprises an arched portal body, a top beam and two side columns, and is arranged at the bottom of the underwater robot; a top cable guiding structure is arranged below the top beam and is used for limiting the vertical movement of the pipe cable; a lateral guiding mechanism is arranged on the two sides of the arched portal body and is used for holding or releasing the pipe cable from the horizontal direction and allowing the pipe cable to move in the axial direction; a bottom lifting mechanism is arranged at the bottom of the arched portal body and is used for supporting the pipe cable; and a driving mechanism is used for driving the lateral guiding mechanism and / or the bottom lifting mechanism to move, so that the device has an openable and closable movement freedom and the size of the limiting space for the pipe cable can be changed. In the closed operation state, the top cable guiding structure, the lateral guiding mechanism and the bottom lifting mechanism jointly form a guiding channel for limiting the pipe cable.

Description

Technical Field

[0001] This invention relates to underwater robot technology, and more specifically to a cable guidance and limiting technology for underwater robots. Background Technology

[0002] In subsea pipeline laying operations, underwater robots (ROVs) need to tow or push pipelines along a predetermined path into the seabed trench while maintaining a stable relative position between the pipeline and the ROV itself. However, the actual seabed environment is extremely complex: ocean currents can reach speeds of 2–3 knots, the seabed topography is uneven, and the pipeline itself, due to its flexibility, is susceptible to lateral swaying and vertical jumping caused by hydrodynamic excitation. If there is a lack of effective guiding and limiting structures between the ROV and the pipeline, the pipeline may deviate from the predetermined path and become entangled or collide with the ROV thrusters, hydraulic lines, or laying equipment, resulting in damage to the outer sheath of the pipeline, breakage of internal optical fibers or conductors, or even interruption of the entire laying operation.

[0003] The Chinese utility model patent announcement with authorization number CN222405704U discloses a deep-sea cable gripping manipulator and underwater robot. The manipulator's claws are driven by opening and closing hydraulic cylinders to grip the cable and are equipped with a direction sensing mechanism. However, this solution lacks vertical restraint on the top of the cable, which may cause the cable to jump out from above the gripper in high currents; moreover, it is essentially a gripper-type grasping method, with the claws sliding in contact with the cable, which can easily damage the PE outer sheath during long-distance laying. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the main objective of this invention is to provide a cable guiding and limiting device for underwater robots, which can effectively suppress the lateral swing and vertical jump of the pipeline on the seabed, and ensure laying accuracy and equipment safety.

[0005] To achieve the above objectives, the technical solution of the present invention is: a cable guiding and limiting device for an underwater robot, comprising: The arched gantry frame is mounted on the bottom of the underwater robot and has a top crossbeam and two side columns. A top cable guide structure is located below the top crossbeam to limit the vertical movement of the cable. Lateral guide mechanisms are provided on both sides of the arched gantry body to grip or release the cable in the horizontal direction and allow the cable to move axially. A bottom support mechanism is located at the bottom of the arched gantry body and is used to support the cable. A drive mechanism is used to drive the lateral guide mechanism and / or the bottom lifting mechanism to move, so that the device has an openable and closeable degree of freedom of movement to change the size of the limiting space for the cable. In the closed operation state, the top cable guide structure, the lateral guide mechanism, and the bottom lifting mechanism together form a guide channel for cable limiting.

[0006] Furthermore, the lateral guiding mechanism includes a double-sided swing arm roller assembly symmetrically arranged on the two side columns of the arched gantry body. The double-sided swing arm roller assembly includes a swing arm and a guide roller arranged at the end of the swing arm. The swing arm is hinged to the corresponding column and can be swung to achieve inward tightening or outward opening and release.

[0007] Furthermore, the bottom support mechanism includes bottom split supports symmetrically arranged on the left and right sides of the bottom of the arched gantry body. The bottom split supports are hinged to the bottom of the corresponding columns and can be rotated around the hinge axis to achieve upward closing support or downward flipping opening release.

[0008] Furthermore, the top cable guide structure includes an inverted U-shaped frame, which is disposed on the top crossbeam, and a guide bushing is provided at the opening of the inverted U-shaped frame.

[0009] Furthermore, the drive mechanism includes a hydraulic cylinder.

[0010] Furthermore, the hydraulic cylinder includes a side swing opening and closing cylinder and a bottom opening and closing cylinder. The side swing opening and closing cylinder is hinged to the swing arm and the column, driving the swing arm to swing. The bottom opening and closing cylinder is hinged to the bottom split support and the column, driving the bottom split support to flip.

[0011] Furthermore, the device also includes a sensing and detection unit, which includes an angle sensor and a pressure sensor. The angle sensor is located at the hinge between the swing arm and the column and is used to detect the swing angle of the swing arm. The pressure sensor is located at the axle of the guide roller and is used to detect the pressure borne by the guide roller.

[0012] The present invention also provides an underwater robot, wherein the underwater robot is equipped with the above-mentioned cable guiding and limiting device.

[0013] Compared with the prior art, the present invention has the following significant advantages: the top cable guiding structure, the double-sided guide roller clamping and the bottom split support form a ring structure, which provides bidirectional limiting in both the lateral and vertical directions. This can effectively suppress the lateral swaying and vertical jump of the pipeline under high current conditions, ensuring laying accuracy and equipment safety. The guide rollers transform traditional sliding friction into rolling friction, avoiding indentation or deformation of the pipeline outer sheath due to excessive clamping force. Attached Figure Description

[0014] The structure of the present invention and its beneficial technical effects will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0015] Figure 1 This is a schematic diagram of the cable guide and limiting device of the present invention in its closed state; Figure 2 for Figure 1 The main view; Figure 3 This is a schematic diagram of the cable guide and limiting device of the present invention in a semi-open state; Figure 4 for Figure 3 The main view; Figure 5 This is a schematic diagram of the cable guide and limiting device of the present invention in its fully open state; Figure 6 for Figure 5 The main view; Figure 7 This is a schematic diagram of the side swing opening and closing hydraulic cylinder connection of the cable guide and limiting device of the present invention; Figure 8 This is a schematic diagram of the bottom opening and closing hydraulic cylinder connection of the cable guide and limiting device of the present invention; Figure 9 A schematic diagram of an underwater robot equipped with a cable guiding and limiting device.

[0016] Explanation of reference numerals in the attached drawings: 1 - Arched gantry main body; 2 - Top cable guide structure; 3 - Double-sided swing arm roller assembly; 4 - Bottom opening and closing cylinder; 5 - Cable guide and limit device; 6 - Side swing opening and closing cylinder; 7 - Sensing and detection unit; 8 - Bottom split support; 9 - Underwater robot body. Detailed Implementation

[0017] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described in this specification are merely for explaining the invention and are not intended to limit the invention.

[0018] Please see Figures 1 to 9 This embodiment provides a cable guiding and limiting device 5 for an underwater robot (ROV). As an independent working module of the underwater robot body 9, it is fixed to the bottom front of the underwater robot's main frame via a mounting base, located behind the ROV thruster assembly, allowing the cable to be introduced into the device from the seabed. The cable guiding and limiting device has an overall downward opening, straddling the cable. It consists of six main parts: an arched gantry body 1, double-sided swing arm roller assemblies 3, a bottom split support 8, a top cable guiding structure 2, hydraulic cylinders (bottom opening / closing cylinder 4, side swing opening / closing cylinder 6), and a sensing and detection unit 7. The overall structure is symmetrical.

[0019] The arched gantry main body 1 includes a top crossbeam and two side columns. The top crossbeam has mounting seats, which are fixed to the bottom of the ROV main frame. The double-sided swing arm roller assembly 3 is mirror-symmetrical, with each side including a swing arm and guide rollers. The swing arms are hinged to the columns and the side-swing opening / closing cylinders 6, respectively. The bottom split support 8 includes a left support and a right support, which are mirror-symmetrical. The left support is hinged to the corresponding bottom opening / closing cylinder 4 and the column of the gantry main body 1, and the right support is similarly hinged. The top cable guide structure 2 is fixed below the top crossbeam of the gantry main body 1. There are two side-swing opening / closing cylinders 6 (symmetrically arranged), each hinged to the corresponding column and swing arm. When the cylinder extends, the piston rod pushes the swing arm to swing, and the double-sided rollers retract to clamp the cable; when the cylinder retracts, the swing arm opens outward. Two bottom opening / closing cylinders 4 (symmetrically arranged on the left and right sides) are hinged to their respective columns and bottom split supports. When the cylinder retracts, the piston rod causes the bottom split support to flip upwards and close; when the cylinder extends, the bottom split support flips downwards and opens. The sensing and detection unit 7 includes an angle sensor and a pressure sensor (not shown in the figure). The angle sensor is located at the hinge between the swing arm and the gantry, and the pressure sensor is located at the axle of the guide roller. These sensors are used to detect the swing angle of the swing arm and the radial force on the guide roller.

[0020] The cable guide and limit device of the present invention has the following three operating states during operation.

[0021] Level 1: Closed Operation State Action process: The side swing opening and closing cylinder 6 extends synchronously, driving the double-sided swing arm roller assembly 3 to retract inward to the set clamping position; the bottom opening and closing cylinder 4 retracts, pulling the bottom split support 8 upward to close via the connecting rod.

[0022] Working principle: The top cable guide structure 2, the double-sided swing arm roller assembly 3, and the bottom split support 8 together form an encircling guide channel, through which the pipeline (cable) passes axially; the rollers roll and fit against the side wall of the pipeline, providing lateral restraint and guidance; the bottom support supports the weight of the pipeline, and the top guide structure restricts vertical movement, achieving pipeline stabilization under high current conditions; the sensing and detection unit 7 provides real-time feedback on contact pressure and offset, and the control system dynamically adjusts the hydraulic cylinder thrust to ensure that the clamping force is always within a safe range, avoiding damage to the pipeline or clamping failure.

[0023] Level 2: Half-open transition state Action sequence: The side swing opening and closing cylinder 6 retracts a certain stroke in sync, and the two side swing arms open slightly outward; the bottom opening and closing cylinder 4 extends a certain stroke in sync, and the bottom split support 8 flips slightly downward, gradually widening the support opening.

[0024] Working principle: The device expands synchronously on both the side and bottom openings, which is used for transitional conditions such as initial pipeline installation, adaptation and adjustment for different pipe diameters, and pipeline joint passage. At this time, some limiting capacity is still retained to prevent the pipeline from moving out significantly, thus balancing operational flexibility and safety.

[0025] Level 3: Fully Released State Action sequence: The side swing opening and closing cylinder 6 retracts completely, and the double swing arms swing to the maximum outward angle; the bottom opening and closing cylinder 4 extends completely, driving the bottom split support 8 to flip downward to the maximum opening angle, forming a fully open opening at the bottom of the device.

[0026] Working principle: It is designed for emergency release and pipeline recovery after operation. The pipeline can be freely released directly from the bottom opening without the need for an overall overturning device or moving the main body of the equipment. The release stroke is short and the response speed is fast. It is not affected by the top equipment structure. In emergency scenarios such as equipment power failure, it can be quickly opened by an external emergency hydraulic source to avoid pipeline being restrained and pulled and damaged.

[0027] The complete working process of the cable guiding and limiting device of this invention covers five major stages: deployment and installation, normal operation, working condition adaptation, emergency release, and final recovery. The entire process is driven by a hydraulic system and uses closed-loop feedback from a sensing unit, corresponding to smooth switching between three levels of opening and closing states. The specific process is as follows: I. Work Preparation and Pipeline Installation Stage Initial positioning: The device is lowered to the seabed operation position along with the underwater robot / deployment system. The initial state is the fully open release state - the side swing opening and closing cylinder 6 is fully retracted, and the double swing arm roller assembly 3 is extended to the maximum angle; the bottom opening and closing cylinder 4 is fully extended, and the bottom split support 8 is flipped downward to fully open. The side and bottom openings of the device are at their maximum size, leaving sufficient operating space for pipeline installation.

[0028] Pipeline placement: The underwater robot's gripping manipulator lifts the submarine cable / pipeline and sends it into the enclosing space from the side or bottom of the device, initially placing it above the closed docking position of the bottom split support 8.

[0029] Half-open pre-clamping: The side swing opening and closing cylinder 6 extends synchronously, driving the double swing arms to retract inward to the half-open state; the bottom opening and closing cylinder 4 retracts synchronously, driving the bottom support to flip upward to the half-closed position, initially limiting the pipeline within the circumferential channel to prevent the pipeline from shifting and coming out, while reserving a margin for pipe diameter adjustment.

[0030] Closure Operation Positioning: The two swing arms continue to retract, the bottom support continues to flip upwards until fully closed, the left and right guide rollers lightly touch the side wall of the pipeline, the bottom V-shaped support supports the bottom of the pipeline, and the top cable guide structure is close to the top surface of the pipeline to form a guide channel. The device enters the operation standby state.

[0031] II. Normal Operation and Pipeline Follow-up Phase Travel guidance and anti-sway: The underwater robot travels along the extension direction of the pipeline, and the pipeline slides axially relative to the device; the double-sided guide rollers roll synchronously with the pipeline, transforming traditional sliding friction into rolling friction, continuously limiting the pipeline laterally and preventing the pipeline from deviating from the working path; the top cable guide structure and the bottom support together restrict the vertical movement of the pipeline, offset the impact of ocean currents and equipment vibration, and achieve anti-sway in both horizontal and vertical directions.

[0032] Clamping force closed-loop control: The pressure sensor in the guide roller shaft of the sensing and detection unit 7 collects the contact pressure between the pipeline and the roller in real time, and the swing arm angle sensor collects the swing arm opening and closing angle in real time; the control system dynamically adjusts the output thrust of the side swing opening and closing cylinder according to the feedback data, so that the clamping force is always maintained within the set safe range, which not only ensures the limiting effect, but also avoids excessive pressure from damaging the outer sheath of the pipeline.

[0033] Path deviation feedback: Based on the angle and displacement data of the two-sided swing arms, the control system can calculate the lateral offset of the pipeline relative to the device and feed the offset signal back to the main equipment's travel control system to assist the main equipment in correcting its travel path and achieve automatic following of the pipeline's direction.

[0034] III. Operating Condition Transition and Adaptive Adjustment Phase When encountering special working conditions such as pipeline joints, pipe diameter changes, pipeline bends, or seabed undulations during operation, the device automatically switches to a semi-open transition state: When the control system predicts a sudden change in the outer diameter of the pipeline (such as the passage of a joint) based on the sensor signal, the control side swing cylinder retracts a certain stroke in sync, and the bottom swing cylinder extends a certain stroke in sync, simultaneously expanding the inner diameter of the circumferential channel to allow the joint / diameter change section to pass smoothly. After passing through the variable diameter section, the machine automatically retracts to the normal clamping force, without needing to stop the machine throughout the entire process, ensuring continuous operation. When operating on curves, a difference occurs between the pressure of the inner and outer rollers and the angle of the swing arm. The control system adjusts the thrust of the cylinders on both sides in real time based on the difference to adapt to the curve of the pipeline and avoid damage to the pipeline due to excessive stress on one side.

[0035] IV. Emergency Release Phase When the equipment experiences abnormal operating conditions such as hydraulic power interruption or equipment failure requiring emergency recovery, the emergency release procedure is triggered: If the equipment's own hydraulic system can still work for a short time, directly control the bottom opening and closing cylinder to fully extend and the side swing opening and closing cylinder to fully retract, the bottom split support to flip down and fully open, and the pipeline to be directly released from the bottom opening by its own weight, thus completing the rapid release; If the equipment itself loses all power, an emergency oil circuit can be connected to an underwater external hydraulic source to directly drive the two sets of opening and closing cylinders to open the ring channel and release the pipeline. The bottom release method is not affected by the top equipment frame or boom structure, and has a short release stroke and fast response speed, which can avoid pulling and bending pipelines during equipment recovery.

[0036] V. Operation Completion and Equipment Recovery Phase After the cable laying / guiding operation is completed, the device is switched to the fully open state and completely disconnected from the pipeline; The main equipment (underwater robot) drives the device away from the pipeline path and lifts it to the water surface to complete the recovery; After coming ashore, the roller bushings and support wear plates are inspected for wear, and the hinged parts and hydraulic sealing elements are maintained and repaired in preparation for the next operation.

[0037] This invention utilizes a unique "three-section encircling" design (top fixed guide, middle side-swinging roller, and bottom split-opening support) with a symmetrical layout based on an arched gantry, achieving full-circumferential encirclement and constraint of the cable. This fundamentally solves the problem in existing technologies where lateral swaying and vertical bouncing of the cable cannot be simultaneously suppressed. Even under harsh conditions with high currents, it maintains stable guiding accuracy, and its bidirectional anti-sway capability is significantly superior to existing solutions. Regarding cable protection, this invention uses guide rollers to transform traditional sliding friction into rolling friction, greatly reducing the risk of wear on the cable's outer sheath. To address the diverse needs of different operational stages, this invention is designed with three operating states: closed operation, half-open joint, and fully open emergency release. Flexible adjustment of multiple opening levels is achieved through independent control or linkage drive of the side-swinging opening and closing cylinders and the bottom opening and closing cylinders. In terms of emergency safety, the bottom split-opening support can be flipped downwards to be fully open, allowing the cable to detach directly from the bottom under its own weight. The release path is free from any structural interference, with a short stroke and fast response speed, providing reliable safety for the cable. Furthermore, this invention directly embeds the angle sensor and pressure sensor into the swing arm hinge shaft and roller shaft, unifying the detection point and execution point. This allows for direct data acquisition and rapid response, enabling simultaneous path deviation detection while achieving pipeline guidance and limiting functions. No additional detection device is required, significantly improving system integration and reducing underwater failure rate.

[0038] Based on the disclosure and teachings of the foregoing specification, those skilled in the art can make appropriate changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the protection scope of the claims of the present invention. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on the present invention.

Claims

1. A cable guiding and limiting device for an underwater robot, characterized in that, include: The arched gantry frame is mounted on the bottom of the underwater robot and has a top crossbeam and two side columns. A top cable guide structure is located below the top crossbeam to limit the vertical movement of the cable. Lateral guide mechanisms are provided on both sides of the arched gantry body to grip or release the cable in the horizontal direction and allow the cable to move axially. A bottom support mechanism is located at the bottom of the arched gantry body and is used to support the cable. A drive mechanism is used to drive the lateral guide mechanism and / or the bottom lifting mechanism to move, so that the device has an openable and closeable degree of freedom of movement to change the size of the limiting space for the cable. In the closed operation state, the top cable guide structure, the lateral guide mechanism, and the bottom lifting mechanism together form a guide channel for cable limiting.

2. The cable guiding and limiting device for underwater robots according to claim 1, characterized in that, The lateral guiding mechanism includes a double-sided swing arm roller assembly symmetrically arranged on the two side columns of the arched gantry body. The double-sided swing arm roller assembly includes a swing arm and a guide roller arranged at the end of the swing arm. The swing arm is hinged to the corresponding column and can be swung to achieve inward tightening or outward opening and release.

3. The cable guiding and limiting device for underwater robots according to claim 1, characterized in that, The bottom support mechanism includes bottom split supports symmetrically arranged on the left and right sides of the bottom of the arched gantry body. The bottom split supports are hinged to the bottom of the corresponding columns and can be rotated around the hinge axis to achieve upward closing support or downward flipping to open and release.

4. The cable guiding and limiting device for underwater robots according to claim 1, characterized in that, The top cable guide structure includes an inverted U-shaped frame, which is disposed on the top crossbeam, and a guide bushing is provided at the opening of the inverted U-shaped frame.

5. The cable guiding and limiting device for an underwater robot according to claim 2 or 3, characterized in that, The drive mechanism includes a hydraulic cylinder.

6. The cable guiding and limiting device for an underwater robot according to claim 5, characterized in that, The hydraulic cylinder includes a side-swing opening and closing cylinder, which is hinged to the swing arm and the column to drive the swing arm to swing.

7. The cable guiding and limiting device for underwater robots according to claim 5, characterized in that, The hydraulic cylinder includes a bottom opening and closing cylinder, which is hinged to the bottom split support and the column, and drives the bottom split support to flip.

8. The cable guiding and limiting device for an underwater robot according to claim 2, characterized in that, The device also includes a sensing and detection unit, which includes an angle sensor and a pressure sensor. The angle sensor is located at the hinge between the swing arm and the column and is used to detect the swing angle of the swing arm. The pressure sensor is located at the axle of the guide roller and is used to detect the pressure borne by the guide roller.

9. An underwater robot, characterized in that, The underwater robot is equipped with a cable guiding and limiting device as described in any one of claims 1 to 8.

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