End effector for moving truss of on-orbit construction space robot and moving method thereof

Abstract

An end effector and a moving method for constructing a space robot truss on-orbit belong to the field of space robot technology. The gripper mechanism is connected to the robot arm, and the lower end cooperates with the truss and is locked and fixed by a damping mechanism. The creeping forward method is as follows: the robot arm is connected to the end effector; the two end effectors clamp the truss; the rear end effector is fixed in position; the front end effector slides to a specified position and is fixed; the rear end effector is released and slides to a specified position and is fixed. The obstacle crossing method is as follows: the robot arm is connected to the end effector; the rear end effector clamps the truss and fixes its position; the front end effector clamps the truss and fixes its position after crossing the obstacle; the rear end effector separates from the truss, crosses the obstacle and clamps the truss again and fixes its position. The present invention improves the on-orbit movement speed, adaptability, operation capability and efficiency of the robot.

Description

Technical Field

[0001] The invention relates to an end effector for moving a truss of an on-orbit construction space robot and a moving method thereof, belonging to the technical field of space robots. Background Art

[0002] The on-orbit assembly of large-scale space facilities first requires the on-orbit manufacturing or deployment of large-scale space truss structures, followed by modular design of the large-scale space facilities. After being launched into orbit, the large-scale space facility modules are transported to the designated location by the space robot system and assembled into the system. Therefore, the on-orbit mobility of space robots is very important.

[0003] At present, the orbital movement modes of space robots mainly include track type, interface type, adhesion type and gripper type.

[0004] The representative of the orbital type is the single-degree-of-freedom movable base MBS of the International Space Station's robotic arm system. The International Space Station's robotic arm can move on the orbit. The advantages of the orbital type are fast movement speed, reliability, and strong load capacity. The disadvantages are that it requires the design of a special mobile track, high cost, and poor applicability.

[0005] The interface type is represented by the Chinese space station robotic arm system. The robotic arm climbs on the surface of the space station by grabbing the end adapter. Its advantages are reliability and strong load capacity, but its disadvantage is that end adapters need to be installed in multiple places.

[0006] The advantage of the adhesive on-orbit crawling method is that it can crawl on the solar film, but its disadvantages are unreliable, low load, and complex control;

[0007] The advantages of the gripper-type on-orbit crawling method are strong adaptability and low cost, while the disadvantage is the need to ensure reliable gripping of the gripper.

[0008] The current on-orbit movement method of space robots is not suitable for on-orbit assembly tasks of future large-scale space facilities. There is an urgent need to study efficient and reliable space robot truss movement tools and methods. Summary of the Invention

[0009] In order to solve the problems existing in the background technology, the present invention provides an end effector for moving a truss of an on-orbit construction space robot and a moving method thereof.

[0010] To achieve the above-mentioned objectives, the present invention adopts the following technical solutions: an end effector for moving a space robot truss built on-orbit, comprising an electromechanical quick-change interface, a clamping mechanism and a damping mechanism; the upper end of the clamping mechanism is connected to the end of the space robot's mechanical arm through the electromechanical quick-change interface, and the lower end of the clamping mechanism is arranged in cooperation with the truss, and is locked and fixedly connected to the truss through the damping mechanism.

[0011] The present invention provides a method for moving an end effector of a space robot truss movement on an on-orbit track by creeping on a continuous truss member, the method comprising the following steps:

[0012] S1: One of the three-arm space robot arms carries the load, and the remaining two arms are connected to the electromechanical quick-change interfaces of the corresponding end effectors;

[0013] S2: The motors of both end effectors are started. The motors rotate to drive the worm, which in turn drives the worm gear, which in turn drives the turntable. The turntable rotates to drive the two gripper fingers to move relative to each other through the cooperation of the cam follower and the sector cam groove, and then closes to clamp the truss.

[0014] S3: The electric push rod of the end effector at the rear end of the two end effectors controls its movable end to extend, so that the damping block and the truss are in frictional contact to fix the position of the end effector at the rear end;

[0015] S4: The electric push rod of the end effector at the front controls the retraction of its movable end, and then the robotic arm at the front controls the end effector at the front to slide forward on the truss to the specified position through the universal ball joint;

[0016] S5: The electric push rod of the end effector at the front end controls its movable end to extend, so that the damping block and the truss are in frictional contact to fix the position of the end effector at the front end;

[0017] S6: The electric push rod of the end effector at the rear end controls the retraction of its movable end, and then the robotic arm at the rear end controls the end effector at the rear end through the universal ball joint to slide forward on the truss to the specified position;

[0018] S7: Repeat S3-S6 until the load is moved to the designated location.

[0019] The present invention provides a method for moving an end effector of an on-orbit construction space robot truss movement across obstacles on a discontinuous truss member, the method comprising the following steps:

[0020] S1: One of the three-arm space robot arms carries the load, and the remaining two arms are connected to the electromechanical quick-change interfaces of the corresponding end effectors;

[0021] S2: The motor of the rear-end end effector is started. The rotation of the motor drives the worm, which in turn drives the worm wheel, which in turn drives the turntable. The turntable, through the cooperation of the cam follower and the sector cam groove, drives the two gripper fingers to move relative to each other and close to clamp the truss. At the same time, the electric push rod of the rear-end end effector controls its movable end to extend, so that the damping block contacts the truss with friction to fix the position of the rear-end end effector.

[0022] S3: The electric push rod of the end effector at the front end controls its movable end to retract. At the same time, the motor of the end effector at the front end is started to rotate. The motor rotation drives the worm, which drives the worm wheel, which drives the turntable. The turntable rotation drives the two gripper fingers to move in the opposite direction through the cooperation of the cam follower and the cam groove, and open and separate from the truss. The robotic arm at the front end controls the end effector at the front end to cross the obstacle.

[0023] S4: When the end effector at the front end crosses the obstacle and reaches the position for grasping the truss, the motor of the end effector at the front end rotates to drive the worm, which in turn drives the worm gear, which in turn drives the turntable, which in turn drives the two gripper fingers to move relative to each other through the cooperation of the cam follower and the cam slot, and then closes to clamp the truss. At the same time, the electric push rod of the end effector at the front end controls its movable end to extend, so that the damping block frictionally contacts the truss to fix the position of the end effector at the front end.

[0024] S5: The electric push rod of the end effector at the rear end controls the retraction of its movable end. The rotation of the motor of the end effector at the rear end drives the worm, which drives the worm wheel, which drives the turntable. The rotation of the turntable drives the two gripper fingers to move in the opposite direction and open and separate from the truss through the cooperation of the cam follower and the cam slot. The robotic arm at the rear end controls the end effector at the rear end to cross the obstacle and re-grasp the truss.

[0025] S6: The end effector at the rear end crosses the obstacle and then repeats S3.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The end effector of the present invention is connected to the robotic arm through an electromechanical quick-change interface, which can be quickly replaced, thereby improving working efficiency; the end effector has two working modes: free sliding and locking on the truss. The end effector is locked on the truss by a high-friction damping block, and has high reliability; the peristaltic crawling mode improves the on-orbit movement speed of the space multi-branch robot, and the leaping movement mode improves the on-orbit movement adaptability of the space multi-branch robot, which can realize large-scale movement of the space robot truss, and improves the large-scale operation capability and efficiency of the on-orbit construction of the space robot system; it saves energy consumption, has low cost, light weight, and low launch cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the present invention;

[0029] Figure 2 yes Figure 1 A top view of

[0030] Figure 3 Schematic diagram of the process of creeping forward on the continuous truss member of the present invention;

[0031] Figure 4 It is a schematic diagram of the process of crossing an obstacle on a discontinuous truss member according to the present invention. DETAILED DESCRIPTION

[0032] The technical solutions of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0033] An end effector for moving a space robot truss on-orbit is described. It includes an electromechanical quick-change interface (3), a gripper mechanism, and a damping mechanism. The upper end of the gripper mechanism is connected to the end of the space robot's manipulator arm via the electromechanical quick-change interface (3). The lower end of the gripper mechanism is cooperating with the truss and is locked and fixed to the truss via the damping mechanism. The electromechanical quick-change interface (3) is prior art and will not be described in detail. The active end of the interface is located on the space robot, allowing the space robot to quickly connect to the end effector via this interface.

[0034] The clamping mechanism includes an upper bracket 11, a motor 13, a worm 14, a worm wheel 15, a turntable 16, a cam follower 17, a lower bracket 18, a slider 19, a slide rail 110, a universal ball 111 and a clamping finger 112; the upper end of the upper bracket 11 is fixedly connected to the electromechanical quick-change interface 3, the lower end of the upper bracket 11 is fixedly connected to the horizontally arranged motor 13 through the motor bracket 12, the output shaft of the motor 13 is coaxially fixedly connected to the worm 14, the worm 14 is meshed with the horizontally arranged worm wheel 15, and the worm wheel 15 is coaxially fixedly connected to the turntable 16; the turntable 16 is provided with two fan-shaped cam grooves 113 throughout its thickness direction, the two The openings of the sector cam grooves 113 are relative and staggered; two parallel slide rails 110 are provided on the lower bracket 18, and each slide rail 110 is provided with two sliders 19. The two sliders 19 located at the same end are fixedly connected to the upper ends of the corresponding gripper fingers 112, and the upper ends of each gripper finger 112 are provided with a cam follower 17, and each cam follower 17 is slidably arranged in the corresponding sector cam groove 113; the cross-section of each gripper finger 112 is a U-shaped structure, and the lower end of each gripper finger 112 is provided with a universal ball 111, and the universal ball 111 is used to realize the sliding connection between the end effector and the truss.

[0035] The damping mechanism includes an electric push rod bracket 21, an electric push rod 22, and a damping block 23. Each of the gripper fingers 112 is provided with at least one through-slot 114 extending through its thickness. The outer wall of each gripper finger 112 is provided with an electric push rod bracket 21. Each electric push rod bracket 21 is fixedly connected to the fixed end of a corresponding electric push rod 22. The movable end of each electric push rod 22 is fixedly connected to a corresponding damping block 23. The damping blocks 23 are provided in a one-to-one correspondence with the through-slots 114. The damping blocks 23 are made of a high-friction material such as rubber, which can provide sufficient friction to prevent the end-of-line actuator from moving.

[0036] like Figure 3 As shown, the present invention provides a method for moving an end effector of a space robot truss on-orbit construction to creep forward on a continuous truss member, which realizes creeping forward on the truss and increases the moving speed; the method comprises the following steps:

[0037] S1: One of the arms of the three-arm space robot carries the load, and the remaining two arms are connected to the electromechanical quick-change interface 3 of the corresponding end effector;

[0038] S2: The motors 13 of the two end effectors are both started. The motor 13 rotates to drive the worm 14, which in turn drives the worm gear 15. The worm gear 15 rotates to drive the turntable 16. The turntable 16 rotates, and the cam follower 17 cooperates with the sector cam groove 113 to drive the two gripper fingers 112 to move relative to each other and close to clamp the truss. When the gripper is closed, the two gripper fingers 112 envelop the square space truss structure.

[0039] S3: The electric push rod 22 of the end effector at the rear end of the two end effectors controls its movable end to extend, so that the damping block 23 is in frictional contact with the truss to fix the position of the end effector at the rear end;

[0040] S4: The electric push rod 22 of the end effector at the front end controls its movable end to retract, and then the robotic arm at the front end controls the end effector at the front end to slide forward on the truss to a specified position through the universal ball 111;

[0041] S5: The electric push rod 22 of the end effector at the front end controls its movable end to extend, so that the damping block 23 is in frictional contact with the truss to fix the position of the end effector at the front end;

[0042] S6: The electric push rod 22 of the end effector at the rear end controls the retraction of its movable end, and then the robotic arm at the rear end controls the end effector at the rear end to slide forward on the truss to a specified position through the universal ball 111;

[0043] S7: Repeat S3-S6 until the load is transported to the specified position, thereby realizing the creeping and crawling of the multi-branch space robot on the space truss.

[0044] like Figure 4 As shown, the present invention provides a method for moving an end effector of a space robot truss on-orbit across obstacles on a discontinuous truss member, thereby improving the adaptability of the space robot. The method comprises the following steps:

[0045] S1: One of the arms of the three-arm space robot carries the load, and the remaining two arms are connected to the electromechanical quick-change interface 3 of the corresponding end effector;

[0046] S2: The motor 13 of the rear end effector of the two end effectors is started. The rotation of the motor 13 drives the worm 14 to rotate. The rotation of the worm 14 drives the worm gear 15 to rotate. The rotation of the worm gear 15 drives the turntable 16 to rotate. The rotation of the turntable 16 drives the two gripper fingers 112 to move relative to each other through the cooperation of the cam follower 17 and the fan-shaped cam groove 113. After closing, they clamp the truss. When the gripper is closed, the two gripper fingers 112 envelop the square space truss structure. At the same time, the electric push rod 22 of the rear end effector controls its movable end to extend, so that the damping block 23 frictionally contacts the truss to fix the position of the rear end effector.

[0047] S3: The electric push rod 22 of the end effector at the front end controls its movable end to retract. At the same time, the motor 13 of the end effector at the front end is started to rotate. The rotation of the motor 13 drives the worm 14 to rotate. The rotation of the worm 14 drives the worm gear 15 to rotate. The rotation of the worm gear 15 drives the turntable 16 to rotate. The rotation of the turntable 16 drives the two gripper fingers 112 to move in the opposite direction and open and separate from the truss through the cooperation of the cam follower 17 and the cam slot 113. The robotic arm at the front end controls the end effector at the front end to cross the obstacle.

[0048] S4: When the end effector at the front end crosses the obstacle and reaches the position for grasping the truss, the motor 13 of the end effector at the front end rotates to drive the worm 14 to rotate, the rotation of the worm 14 drives the worm gear 15 to rotate, the rotation of the worm gear 15 drives the turntable 16 to rotate, the rotation of the turntable 16 drives the two gripper fingers 112 to move relative to each other through the cooperation of the cam follower 17 and the cam groove 113, and then closes to clamp the truss. At the same time, the electric push rod 22 of the end effector at the front end controls its movable end to extend, so that the damping block 23 frictionally contacts the truss to fix the position of the end effector at the front end;

[0049] S5: The electric push rod 22 of the end effector at the rear end controls the retraction of its movable end. The motor 13 of the end effector at the rear end rotates, driving the worm 14 to rotate. The rotation of the worm 14 drives the worm gear 15 to rotate. The rotation of the worm gear 15 drives the turntable 16 to rotate. The rotation of the turntable 16 drives the two gripper fingers 112 to move in the opposite direction and open to separate from the truss through the cooperation of the cam follower 17 and the cam slot 113. The robotic arm at the rear end controls the end effector at the rear end to cross the obstacle and re-grasp the truss.

[0050] S6: The end effector at the rear end crosses the obstacle and then repeats S3.

[0051] The present invention has three working modes:

[0052] The first working mode is that after the clamp is closed, it slides freely on the space truss by relying on the universal ball inside the clamp;

[0053] The second working mode is performed by the damping mechanism on the gripper, which fixes the end effector to the spatial truss member through friction;

[0054] The third working mode is that when encountering the connection of the space truss rods, the end effector clamp can be opened, and then the space robot manipulates the end effector to cross the rod connection and cooperate with the next rod.

[0055] Therefore, after the spatial multi-branch robot is equipped with the end effector of the present invention, it has two spatial truss movement modes:

[0056] The first is to realize the creeping movement of the spatial multi-branch robot on the continuous truss by using the two working modes of free sliding and fixed end effector on the truss and coordinating with the movement of the spatial multi-branch robot;

[0057] The second is to realize the spanning movement capability of the spatial multi-branch robot on the truss through two working modes: fixing the end effector on the truss and opening and closing the gripper, and coordinating the movement of the spatial multi-branch robot.

[0058] The creeping crawling method increases the on-orbit movement speed of the space multi-branch robot and saves on-orbit movement energy consumption; the straddling crawling method enables the space multi-branch robot to cross obstacles and improve its adaptability on-orbit movement. Therefore, the present invention improves the truss movement speed and on-orbit work efficiency of the space multi-branch robot.

[0059] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0060] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. An end effector for moving a truss of a space robot in orbit, characterized by: The invention comprises an electromechanical quick-change interface (3), a clamping mechanism and a damping mechanism; the upper end of the clamping mechanism is connected to the end of the space robot arm through the electromechanical quick-change interface (3), the lower end of the clamping mechanism is arranged in cooperation with the truss, and is locked and fixedly connected to the truss through the damping mechanism; the clamping mechanism comprises an upper bracket (11), a motor (13), a worm (14), a worm gear (15), a turntable (16), a cam follower (17), a lower bracket (18), a slider (19), a slide rail (110), a universal ball (111) and a clamping finger (112) The upper end of the upper bracket (11) is fixedly connected to the electromechanical quick-change interface (3), the lower end of the upper bracket (11) is fixedly connected to the horizontally arranged motor (13), the output shaft of the motor (13) is coaxially fixedly connected to the worm (14), the worm (14) is meshed with the horizontally arranged worm wheel (15), and the worm wheel (15) is coaxially fixedly connected to the turntable (16); the turntable (16) is provided with two sector-shaped cam grooves (113), the two sector-shaped cam grooves (113) are opposite and staggered; the lower bracket (18) is provided with two parallel The slide rails (110) are arranged in a row, and each of the slide rails (110) is provided with two sliders (19). The two sliders (19) located at the same end are fixedly connected to the upper end of the corresponding gripper finger (112). The upper end of each gripper finger (112) is provided with a cam follower (17), and each cam follower (17) is slidably arranged in the corresponding fan-shaped cam groove (113); the lower end of each gripper finger (112) is provided with a universal ball (111), and the universal ball (111) is used to realize the sliding connection between the end effector and the truss. The damping mechanism comprises an electric push rod bracket (21), an electric push rod (22) and a damping block (23); each of the clamping fingers (112) is provided with at least one through slot (114); the outer wall of each clamping finger (112) is provided with an electric push rod bracket (21); each of the electric push rod brackets (21) is fixedly connected to the fixed end of the corresponding electric push rod (22); the movable end of each of the electric push rods (22) is fixedly connected to the corresponding damping block (23); the damping blocks (23) and the through slots (114) are arranged in a one-to-one correspondence.

2. A method for moving an end effector of an on-orbit construction space robot truss movement by creeping on a continuous truss member according to claim 1, characterized in that: The method comprises the following steps: S1: One of the three-arm space robot arms carries the load, and the remaining two arms are connected to the corresponding electromechanical quick-change interface (3) of the end effector; S2: The motors (13) of the two end effectors are both started, the motor (13) rotates to drive the worm (14), the worm (14) rotates to drive the worm wheel (15), the worm wheel (15) rotates to drive the turntable (16), the turntable (16) rotates to drive the two gripper fingers (112) to move relative to each other through the cooperation of the cam follower (17) and the fan-shaped cam groove (113), and then close to clamp the truss; S3: The electric push rod (22) of the end effector located at the rear end of the two end effectors controls its movable end to extend, so that the damping block (23) is in frictional contact with the truss to fix the position of the end effector located at the rear end; S4: The electric push rod (22) of the end effector at the front end controls the retraction of its movable end, and then the robotic arm at the front end controls the end effector at the front end to slide forward on the truss to a specified position through the universal ball (111); S5: The electric push rod (22) of the end effector at the front end controls its movable end to extend, so that the damping block (23) is in frictional contact with the truss to fix the position of the end effector at the front end; S6: The electric push rod (22) of the end effector at the rear end controls the retraction of its movable end, and then the robotic arm at the rear end controls the end effector at the rear end to slide forward on the truss to a specified position through the universal ball (111); S7: Repeat S3-S6 until the load is moved to the designated location.

3. A method for moving an end effector of an on-orbit construction space robot truss movement across obstacles on a non-continuous truss member according to claim 1, characterized in that: The method comprises the following steps: S1: One of the three-arm space robot arms carries the load, and the remaining two arms are connected to the corresponding electromechanical quick-change interface (3) of the end effector; S2: The motor (13) of the end effector at the rear end of the two end effectors is started, the motor (13) rotates to drive the worm (14), the worm (14) rotates to drive the worm wheel (15), the worm wheel (15) rotates to drive the turntable (16), the turntable (16) rotates to drive the two gripping fingers (112) to move relative to each other through the cooperation of the cam follower (17) and the fan-shaped cam groove (113), and then close to clamp the truss; at the same time, the electric push rod (22) of the end effector at the rear end controls its movable end to extend, so that the damping block (23) is in frictional contact with the truss to fix the position of the end effector at the rear end; S3: The electric push rod (22) of the end effector at the front end controls the retraction of its movable end, and at the same time, the motor (13) of the end effector at the front end is started to rotate, the rotation of the motor (13) drives the worm (14) to rotate, the rotation of the worm (14) drives the worm wheel (15) to rotate, the rotation of the worm wheel (15) drives the turntable (16) to rotate, the rotation of the turntable (16) drives the two gripper fingers (112) to move in the opposite direction and open and separate from the truss through the cooperation of the cam follower (17) and the cam groove (113), and the mechanical arm at the front end controls the end effector at the front end to cross the obstacle; S4: When the end effector at the front end crosses the obstacle and reaches the position of grasping the truss, the motor (13) of the end effector at the front end rotates to drive the worm (14), the rotation of the worm (14) drives the worm wheel (15), the rotation of the worm wheel (15) drives the turntable (16), the rotation of the turntable (16) drives the two gripping fingers (112) to move relative to each other through the cooperation of the cam follower (17) and the cam groove (113) to close and clamp the truss. At the same time, the electric push rod (22) of the end effector at the front end controls its movable end to extend, so that the damping block (23) is in friction contact with the truss to fix the position of the end effector at the front end; S5: The electric push rod (22) of the end effector at the rear end controls the retraction of its movable end, the motor (13) of the end effector at the rear end rotates to drive the worm (14) to rotate, the rotation of the worm (14) drives the worm wheel (15) to rotate, the rotation of the worm wheel (15) drives the turntable (16) to rotate, the rotation of the turntable (16) drives the two gripper fingers (112) to move in the opposite direction and open to separate from the truss through the cooperation of the cam follower (17) and the cam groove (113), and the robotic arm at the rear end controls the end effector at the rear end to cross the obstacle and re-grasp the truss; S6: The end effector at the rear end crosses the obstacle and then repeats S3.

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