Underwater robot docking and recovery mechanism with seven degrees of freedom in parallel and underwater robot

Abstract

The present invention provides a seven-degree-of-freedom parallel underwater robot docking and recovery mechanism and an underwater robot, comprising a seven-degree-of-freedom parallel robot, a base, a control module, and a positioning module; the seven-degree-of-freedom parallel robot is electrically connected to the control module, the positioning module is electrically connected to the control module, the seven-degree-of-freedom parallel robot comprises a static platform and a dynamic platform, the static platform is mounted on the base, the static platform and the dynamic platform are connected by a plurality of branches, the seven-degree-of-freedom parallel robot can perform seven-degree-of-freedom motion by cooperating with the plurality of branches, and the dynamic platform is used to clamp the underwater robot. The present invention obtains the underwater robot's posture information through the positioning module, calculates the posture information through the control module, controls the seven-degree-of-freedom parallel robot to move to a suitable position and angle, realizes the grasping and releasing of the underwater robot, helps to reduce the posture requirements for the underwater robot during capture, helps to obtain a larger capture range, and helps to improve the docking success rate.

Description

Technical Field

[0001] The present invention relates to the field of underwater robots, and in particular to a seven-degree-of-freedom parallel underwater robot docking and recovery mechanism and the underwater robot. Background Art

[0002] Autonomous underwater vehicles (AUVs), as an important underwater operation tool, are extremely powerful and effective when performing short-endurance missions. However, current AUVs have limited energy storage capabilities, typically limiting mission endurance to a few hours or days, restricting their widespread use in large spaces and for extended periods. Fundamentally, automatic deployment and recovery technology to recharge AUVs and transmit data is an effective way to extend AUV operation time and improve their operational capabilities.

[0003] Current underwater automated docking and recovery technologies mostly rely on navigation technology and the AUV's own power to achieve docking and capture. However, in the complex ocean environment, affected by waves and currents, the AUV's own power performance and navigation accuracy are limited, making it difficult to achieve a high success rate of automated docking and recovery.

[0004] The existing Chinese patent publication number CN114394215A discloses an active capture underwater submersible docking mechanism and its working method, which relate to the field of underwater docking technology. The mechanism includes a clamping module, a six-degree-of-freedom parallel robot, an underwater base, a control module and a positioning module; the control module is connected to the six-degree-of-freedom parallel robot, the six-degree-of-freedom parallel robot is connected to the underwater base, a battery is provided on the underwater base, the battery is connected to the positioning module, the top of the six-degree-of-freedom parallel robot is connected to the clamping module, and the clamping module moves synchronously with the six-degree-of-freedom parallel robot through the control module; the positioning module can obtain the position information of the underwater submersible, so that the control module can control the position of the gripper accordingly to achieve the capture and energy replenishment of the underwater submersible.

[0005] The inventors believe that there is an urgent need to design and develop an automated underwater docking and recovery system that is independent of the AUV's own power and has a high capture success rate. Furthermore, it is necessary to reduce the posture requirements for the underwater robot during capture in order to achieve a larger capture range and improve the docking success rate. Summary of the Invention

[0006] In view of the defects in the prior art, the purpose of the present invention is to provide a seven-degree-of-freedom parallel underwater robot docking and recovery mechanism and an underwater robot.

[0007] According to the present invention, a seven-degree-of-freedom parallel underwater robot docking and recovery mechanism includes: a seven-degree-of-freedom parallel robot, a base, a control module and a positioning module; the seven-degree-of-freedom parallel robot is electrically connected to the control module, and the positioning module is electrically connected to the control module. The seven-degree-of-freedom parallel robot includes a static platform and a dynamic platform, the static platform is installed on the base, and the static platform and the dynamic platform are connected by multiple branches. The seven-degree-of-freedom parallel robot can perform seven-degree-of-freedom movement through the cooperation of the multiple branches, and the dynamic platform is used to clamp the underwater robot.

[0008] Preferably, a battery is provided on the base, and the battery is electrically connected to the seven-degree-of-freedom parallel robot, the control module and the positioning module respectively.

[0009] Preferably, the three branch chains are evenly arranged on the static platform along the circumferential direction.

[0010] Preferably, each of the branch chains comprises a planar four-bar linkage, and the planar four-bar linkage is mounted on the static platform via a first rotation pair.

[0011] Preferably, a first connecting block is provided at the bottom of the planar four-bar linkage mechanism, and the bottom of the planar four-bar linkage mechanism is connected to the first connecting block via a second rotation pair and a sixth rotation pair respectively, and the first connecting block is mounted on the first rotation pair.

[0012] Preferably, the axis direction of the first rotation pair is vertically upward, and the axis directions of the second rotation pair and the sixth rotation pair are both perpendicular to the axis direction of the first rotation pair.

[0013] Preferably, the movable platform comprises a three-fold symmetrical Bricard spatial six-bar linkage, wherein the movable platform comprises six connecting rods connected end to end, and any two adjacent connecting rods are connected via a revolute pair.

[0014] Preferably, the top rod of the planar four-bar linkage mechanism has an extension rod extending in the direction close to the moving platform, the end of the extension rod is provided with a ball joint, the ball joint is connected to the fifth link, and the fifth link is connected to the moving platform through a seventh revolving pair.

[0015] Preferably, the six rotating pairs on the movable platform include three seventh rotating pairs arranged at intervals, and the other three rotating pairs are all provided with clamping claws.

[0016] An underwater robot provided by the present invention can be captured by the above-mentioned seven-degree-of-freedom parallel underwater robot docking and recovery mechanism and docked therewith.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The present invention obtains the position and posture information of the underwater robot through the positioning module, solves the position and posture information through the control module, controls the seven-degree-of-freedom parallel robot to move to the appropriate position and angle, and realizes the grasping and releasing of the underwater robot. This helps to reduce the posture requirements for the underwater robot during capture, helps to obtain a larger capture range, and helps to improve the docking success rate.

[0019] 2. The present invention has a larger translational workspace and rotational workspace, can avoid singular points of the mechanism, and has the advantages of high rigidity, high precision, good dynamic performance, etc.

[0020] 3. The present invention adopts a triple-symmetrical Bricard mechanism articulated dynamic platform as a gripper, and the end gripper can be controlled by a motor at the base, which is beneficial to the protection of the underwater motor and the optimization of the mechanism performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0022] Figure 1 This is a schematic diagram of the overall structure of the seven-degree-of-freedom parallel underwater robot docking and recovery mechanism of the present invention;

[0023] Figure 2 This is a schematic diagram of the overall structure of a seven-degree-of-freedom parallel robot mainly embodied in the present invention;

[0024] Figure 3 This is a schematic diagram of the overall structure of a single branched chain;

[0025] Figure 4 This is a schematic diagram of the overall structure of the dynamic platform of the triple symmetrical Bricard mechanism embodied in the present invention;

[0026] Figure 5 This is a block diagram of the working method of the docking mechanism for actively capturing an underwater robot, which is mainly embodied in the present invention.

[0027] As shown in the figure:

[0028] 7-DOF parallel robot 1 base 2 control module 3

[0029] Positioning module 4 Battery 5 Underwater robot 6

[0030] Static platform 7 Dynamic platform 8 Planar four-bar linkage 9

[0031] First rotation pair 10 First connecting block 11 Second rotation pair 12

[0032] First connecting rod 13 Third rotating pair 14 Second connecting rod 15

[0033] Fourth rotational pair 16 Third connecting rod 17 Fifth rotational pair 18

[0034] Fourth connecting rod 19 Sixth revolving pair 20 Ball joint 21

[0035] Fifth connecting rod 22 Seventh rotation pair 23 First bricard rotation pair 24 First bricard connecting rod 25 Second bricard rotating pair 26 Second bricard connecting rod 27

[0036] Third bricard rotation pair 28 Third bricard connecting rod 29 Fourth bricard rotation pair 30 Fourth Bricard connecting rod 31 Fifth Bricard rotating pair 32 Fifth Bricard connecting rod 33

[0037] Sixth bricard rotating pair 34 Sixth bricard connecting rod 35 Clamp 36 DETAILED DESCRIPTION

[0038] The present invention will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several changes and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0039] Example 1

[0040] like Figure 1 As shown, a seven-degree-of-freedom parallel underwater robot docking and recovery mechanism provided according to the present invention includes: a seven-degree-of-freedom parallel robot 1, a base 2, a control module 3 and a positioning module 4; the seven-degree-of-freedom parallel robot 1 is electrically connected to the control module 3, and the positioning module 4 is electrically connected to the control module 3. The seven-degree-of-freedom parallel robot 1 includes a static platform 7 and a dynamic platform 8. The static platform 7 is installed on the base 2. The static platform 7 and the dynamic platform 8 are connected by multiple branches. The seven-degree-of-freedom parallel robot 1 can perform seven-degree-of-freedom movement through the cooperation of multiple branches. The dynamic platform 8 is used to clamp the underwater robot 6.

[0041] The base 2 is installed on the seabed, a large underwater vehicle, a surface vessel, or an underwater floating platform. A battery 5 is mounted on the base 2 and electrically connected to the seven-degree-of-freedom parallel robot 1, the control module 3, and the positioning module 4. The battery 5 is powered by one or more power generation devices selected from the group consisting of solar energy, wave energy, tidal energy, geothermal energy, and wind energy.

[0042] The positioning module 4 obtains the position information of the underwater robot 6 and transmits it to the control module 3. The control module 3 calculates the position information and controls the motor rotation of the 7-DOF parallel robot 1, so that the 7-DOF parallel robot 1 moves to the appropriate position and angle to achieve the grasping and releasing of the underwater robot 6. This application has strong adaptability, high precision, good dynamic performance, and a higher docking success rate.

[0043] This application takes the example of three branch chains being evenly arranged along the circumferential direction on the static platform 7 .

[0044] like Figure 2 As shown, each branch chain includes a planar four-bar linkage 9 , which is mounted on the static platform 7 via a first rotation pair 10 .

[0045] like Figure 3 As shown, a first connecting block 11 is provided at the bottom of the planar four-bar linkage 9. The bottom of the planar four-bar linkage 9 is connected to the first connecting block 11 through a second rotational pair 12 and a sixth rotational pair 20, respectively. The first connecting block 11 is mounted on the first rotational pair 10. The planar four-bar linkage 9 includes a first link 13, a second link 15, a third link 17, and a fourth link 19 forming a parallelogram. The first link 13 is connected to the first connecting block 11 through the second rotational pair 12, the second link 15 is connected to the first link 13 through the third rotational pair 14, the third link 17 is connected to the second link 15 through the fourth rotational pair 16, the fourth link 19 is connected to the third link 17 through the fifth rotational pair 18, and the fourth link 19 is connected to the first connecting block 11 through the sixth rotational pair 20. The second rotational pair 12 and the sixth rotational pair 20 are respectively located on both sides of the first connecting block 11.

[0046] The axial direction of the first rotating pair 10 is vertically upward, the axial directions of the second rotating pair 12 and the sixth rotating pair 20 are both perpendicular to the axial direction of the first rotating pair 10, and the axial direction of the sixth rotating pair 20 coincides with the axial direction of the second rotating pair 12, and the axial directions of the second rotating pair 12 are parallel to the third rotating pair 14, the fourth rotating pair 16, and the fifth rotating pair 18.

[0047] The first, second, and sixth revolving pairs 10, 12, and 20 of the three branches are all driven pairs, driven by motors. The seven-DOF parallel robot 1 is driven by nine motors, powered by batteries 5. The control module 3 controls the motor rotation angles, enabling grasping and releasing in any desired posture within the workspace.

[0048] like Figure 4As shown, the dynamic platform 8 comprises a three-fold symmetrical Bricard spatial six-bar linkage. The dynamic platform 8 comprises six connecting rods connected end-to-end, with any two adjacent connecting rods connected by a revolute pair. The dynamic platform 8 includes a first Bricard link 25, a first Bricard revolute pair 24, a second Bricard link 27, a second Bricard revolute pair 26, a third Bricard link 29, a third Bricard revolute pair 28, a fourth Bricard link 31, a fourth Bricard revolute pair 30, a fifth Bricard link 33, a fifth Bricard revolute pair 32, a sixth Bricard link 35, and a sixth Bricard revolute pair 34. The Bricard mechanism's connecting rods are all the same length and are connected sequentially via the revolute pairs at the end to form a closed-loop mechanism. The angle between the axes of the first, second, third, fourth, fifth, and sixth Bricard revolute pairs is α; the angle between the axes of the second, third, fourth, fifth, and sixth Bricard revolute pairs is 360-α; the angle α ranges from 0 to 180°.

[0049] The six rotating pairs on the movable platform 8 include three seventh rotating pairs 23 arranged at intervals, and the other three rotating pairs are each provided with a clamping claw 36 .

[0050] The top rod of the planar four-bar linkage 9 extends toward the moving platform 8. A ball joint 21 is provided at the end of the extension rod. A fifth link 22 is connected to the ball joint 21. The fifth link 22 is connected to the moving platform 8 via a seventh revolute joint 23. The ball joint 21 may be a composite ball joint with three rotation axes intersecting at one point.

[0051] like Figure 5 As shown, the working method of this application specifically includes the following steps:

[0052] Step 1: When the underwater robot 6 moves to the capture workspace of the docking mechanism, the positioning module 4 detects the position information of the underwater robot and transmits the information to the control module 3.

[0053] In step 2, the control module 3 performs posture calculation based on the current posture of the seven-degree-of-freedom parallel robot 1, and controls the nine drive motors of the seven-degree-of-freedom parallel robot 1 to rotate so that the Bricard dynamic platform gripper 36 maintains the maximum opening angle and the posture is aligned with the posture of the underwater robot 6.

[0054] Step 3: The control module 3 keeps the Bricard moving platform 8 in a constant position, and the three grippers 36 gradually close to grasp and fix the underwater robot 6, and the capture is completed.

[0055] Step 4. The control module 3 drives the motor to keep the angle of the clamping jaws 36 unchanged and move the underwater robot 6 to a position away from the base. The clamping jaws 36 open and release the underwater robot 6.

[0056] This application utilizes a 7-degree-of-freedom (DOF) driven redundant parallel mechanism as a docking and recovery mechanism. Compared to traditional passive recovery devices, this mechanism offers a larger capture range and reduces the posture requirements for the underwater robot 6 during capture. This application offers advantages such as a larger translational and rotational workspace, the ability to avoid singularities in the mechanism, high rigidity, high precision, and excellent dynamic performance, effectively improving the docking success rate. This application utilizes a triple-symmetrical Bricard mechanism articulated dynamic platform as a gripper, which can be controlled by a motor at the base 2, facilitating underwater motor protection and optimizing mechanism performance.

[0057] Example 2

[0058] An underwater robot provided by the present invention can be captured by the seven-degree-of-freedom parallel underwater robot docking and recovery mechanism described in Example 1 to achieve precise docking.

[0059] In the description of this application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0060] The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. The embodiments of this application and the features in the embodiments may be combined with each other in any manner unless there is a conflict.

Claims

1. A seven-degree-of-freedom parallel underwater robot docking and recovery mechanism, characterized in that: include: A seven-degree-of-freedom parallel robot (1), a base (2), a control module (3), and a positioning module (4); The seven-degree-of-freedom parallel robot (1) is electrically connected to the control module (3), and the positioning module (4) is electrically connected to the control module (3). The seven-degree-of-freedom parallel robot (1) includes a static platform (7) and a dynamic platform (8), wherein the static platform (7) is mounted on the base (2), and the static platform (7) and the dynamic platform (8) are connected via a plurality of branch chains. The seven-degree-of-freedom parallel robot (1) can perform seven-degree-of-freedom motion through the cooperation of the plurality of branch chains, and the dynamic platform (8) is used to clamp the underwater robot (6); The three branch chains are evenly arranged on the static platform (7) along the circumferential direction; The branch chains each include a planar four-bar linkage (9), and the planar four-bar linkage (9) is mounted on the static platform (7) via a first rotation pair (10); A first connecting block (11) is provided at the bottom of the planar four-bar linkage (9), and the bottom of the planar four-bar linkage (9) is connected to the first connecting block (11) via a second rotation pair (12) and a sixth rotation pair (20), respectively, and the first connecting block (11) is mounted on the first rotation pair (10); The movable platform (8) comprises a three-fold symmetrical Bricard spatial six-link mechanism, and the movable platform (8) comprises six connecting rods connected end to end, and any two adjacent connecting rods are connected via a revolute pair.

2. The seven-degree-of-freedom parallel underwater robot docking and recovery mechanism according to claim 1, characterized in that: A storage battery (5) is provided on the base (2), and the storage battery (5) is electrically connected to the seven-degree-of-freedom parallel robot (1), the control module (3), and the positioning module (4), respectively.

3. The seven-degree-of-freedom parallel underwater robot docking and recovery mechanism according to claim 1, characterized in that: The axis direction of the first rotating pair (10) is vertically upward, and the axis directions of the second rotating pair (12) and the sixth rotating pair (20) are both perpendicular to the axis direction of the first rotating pair (10).

4. The seven-degree-of-freedom parallel underwater robot docking and recovery mechanism according to claim 1, characterized in that: The top rod of the planar four-bar linkage (9) is extended with an extension rod in a direction close to the movable platform (8), and a ball joint (21) is provided at the end of the extension rod. A fifth link (22) is connected to the ball joint (21), and the fifth link (22) is connected to the movable platform (8) through a seventh rotation pair (23).

5. The seven-degree-of-freedom parallel underwater robot docking and recovery mechanism according to claim 4, characterized in that: The six rotating pairs on the movable platform (8) include three seventh rotating pairs (23) arranged at intervals, and the other three rotating pairs are each provided with a clamping claw (36).

6. An underwater robot, characterized in that: It can be captured by and docked with the seven-degree-of-freedom parallel underwater robot docking and recovery mechanism described in any one of claims 1 to 5.

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