A two-rotation and one-transfer parallel robot mechanism with movable guide rails

Abstract

The present application provides a two-rotation and one-translation parallel robot mechanism containing a movable guide rail. The three movable pairs are set to enable the movable platform to achieve one degree of freedom of movement, and the three universal pairs can enable the movable platform to achieve two degrees of rotational freedom. The rotational movement of the movable guide rail relative to the fixed guide rail can enable the mechanism to avoid the occurrence of accompanying movement; the technical solution of the present application decouples the rotational degree of freedom from the movement degree of freedom, so that the parallel mechanism has better posture adjustment capability; the technical solution of the present application avoids the occurrence of accompanying movement, so that the mechanism shaft will not undergo unexpected movement after continuous rotation, the moving platform movement accuracy is higher, and the application range is also wider.

Description

Technical Field

[0001] The present invention relates to the field of robotics technology, in particular to a two-rotation-one-transfer parallel robot mechanism with a movable guide rail. Background Art

[0002] Low-degree-of-freedom parallel robots are widely used in various fields. For example, the application number CN202111090035.5 discloses an RRP-type two-turn-one-shift parallel mechanism with two skew axes. Most low-degree-of-freedom parallel robots have constrained movements in other directions in addition to the movement in the nominal degree-of-freedom direction, that is, after continuous rotation, unexpected movement may occur, which is called accompanying movement. The directions of the two rotating axes of the two-turn-one-shift parallel mechanism with accompanying movement also become very complicated, and the accompanying movement is an inherent property of the mechanism itself, which is difficult to eliminate through parameter optimization or compensated in real time by the robot's own control system, thus affecting the actual application scenarios of such mechanisms. Summary of the Invention

[0003] In order to solve the problem in the prior art that the accompanying motion occurs during the movement of the two-turn-one-shift mechanism, resulting in limited application scenarios, the present invention provides a two-turn-one-shift parallel robot mechanism with a movable guide rail, which can overcome the accompanying motion in the movement of the two-turn-one-shift parallel mechanism and reduce the complexity of the movement of the two rotation axes of the mechanism.

[0004] The technical solution of the present invention is as follows: a two-rotation and one-transfer parallel robot mechanism with a movable guide rail, comprising: a moving platform and three branch chains with the same structure;

[0005] It is characterized in that it also includes: a fixed guide rail and a movable guide rail;

[0006] The fixed guide rail and the movable guide rail are both arranged on the bottom plane, and the movable guide rail is connected to the fixed guide rail via a first rotating pair;

[0007] The branch chain includes: a vertical guide rail, a rotating seat, a first moving pair, a second moving pair and a universal joint;

[0008] The vertical guide rail is arranged perpendicular to the bottom plane; among the three vertical guide rails, two of the vertical guide rails are installed on the fixed guide rail through a moving pair, and one of the vertical guide rails is installed on the moving guide rail through a moving pair;

[0009] The plane formed by the movable guide rail and the vertical guide rail connected thereto is perpendicular to the bottom plane, and intersects with the plane formed by the other two vertical guide rails on a line perpendicular to the bottom plane; the axes of the movable pair 1 and the movable pair 2 are perpendicular to each other;

[0010] In each of the branch chains, the rotating seat is installed on the vertical guide rail through the second moving pair; the rotating seat is connected to the moving platform through the universal pair.

[0011] It is further characterized by:

[0012] The three moving pairs are configured as driving pairs;

[0013] The universal joint is connected to the rotating seat via a first rotating joint, and is connected to the movable platform via a second rotating joint; and the rotating axes of the first rotating joint and the second rotating joint are perpendicular to each other;

[0014] The universal joint comprises a T-shaped structure, wherein the horizontal rod of the T-shaped structure and the rotating seat constitute the first rotating joint, and the vertical rod of the T-shaped structure and the moving platform constitute the second rotating joint;

[0015] The axes of the two moving pairs installed on the fixed guide rail are located on the same straight line.

[0016] The present application provides a two-rotation and one-translation parallel robot mechanism containing a movable guide rail. The three movable pairs are set to enable the movable platform to achieve one degree of freedom of movement, and the three universal pairs can enable the movable platform to achieve two degrees of rotational freedom. The rotational movement of the movable guide rail relative to the fixed guide rail can enable the mechanism to avoid the occurrence of accompanying movement; the technical solution of the present application decouples the rotational degree of freedom from the movement degree of freedom, so that the parallel mechanism has better posture adjustment capability; the technical solution of the present application avoids the occurrence of accompanying movement, so that the mechanism shaft will not undergo unexpected movement after continuous rotation, the moving platform movement accuracy is higher, and the application range is also wider. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the structure of a two-rotation and one-transfer parallel robot mechanism with a movable guide rail;

[0018] Figure 2 for Figure 1 The schematic diagram of the structure after enlarging point B in the middle;

[0019] Figure 3 Schematic diagram of the general posture of the moving guide rail when it rotates. DETAILED DESCRIPTION

[0020] like Figure 1 As shown, the present application includes a two-rotation and one-transfer parallel robot mechanism with a movable guide rail, which includes: a fixed guide rail 4, a movable guide rail 5, a movable platform 6 and three branches; the three branches are: a first branch chain 1, a second branch chain 2 and a third branch chain 3.

[0021] The fixed guide rail 4 and the movable guide rail 5 are both arranged on the bottom plane, and the movable guide rail 5 is connected to the fixed guide rail 4 via a first rotating pair 7. This application improves the two-rotation-one-translation parallel mechanism in the prior art. The movable guide rail 5 and the fixed guide rail 4 cooperate to form a parallel mechanism containing a movable guide rail. By adding a rotatable movable guide rail, the movable platform still has two rotations and one translation degrees of freedom, but with higher flexibility and more application scenarios.

[0022] The three branches have the same structure, each comprising a vertical guide rail, a rotating seat, a movable pair 1, a movable pair 2, and a universal joint. The first branch 1 comprises a first vertical guide rail 101, a first rotating seat 102, a first movable pair 11, a first movable pair 2 12, and a first universal joint 13. The second branch 2 comprises a second vertical guide rail 201, a second rotating seat 202, a second movable pair 1 21, a second movable pair 22, and a second universal joint 23. The third branch 3 comprises a third vertical guide rail 301, a third rotating seat 302, a third movable pair 1 31, a third movable pair 2 32, and a third universal joint 33. The first rotating pair 7 is located between the first movable pair 11 and the second movable pair 1 21, and the rotation axis of the first rotating pair 7 is perpendicular to the bottom plane where the fixed guide rail 4 and the movable guide rail 5 are located.

[0023] Each vertical guide rail is arranged perpendicular to the bottom plane. Two of the three vertical guide rails are mounted on the fixed guide rail 4 via a first movable joint, and one is mounted on the movable guide rail 5 via a first movable joint. The axes of the two movable joints mounted on the fixed guide rail 4 are aligned. In this embodiment, the first vertical guide rail 101 and the second vertical guide rail 201 are mounted on the fixed guide rail 4 via a first movable joint 11 and a second movable joint 21, respectively. The third vertical guide rail 301 is mounted on the movable guide rail 5 via a third movable joint 31. The axes of the first movable joint 11 and the second movable joint 21 are aligned.

[0024] The plane formed by the movable guide rail 5 and the third vertical guide rail 301 is perpendicular to the bottom plane, and intersects with the plane formed by the first vertical guide rail 101 and the second vertical guide rail 201 on a line A perpendicular to the bottom plane.

[0025] In each branch chain, the axes of moving pair 1 and moving pair 2 are perpendicular to each other; at the same time, the rotating seat is mounted on the vertical guide rail through moving pair 2, and the rotating seat is connected to the moving platform 6 through the universal joint. That is, the axes of the first moving pair 11 and the first moving pair 2 12 are perpendicular to each other; the axes of the second moving pair 1 21 and the second moving pair 2 22 are perpendicular to each other; the axes of the third moving pair 1 31 and the third moving pair 2 32 are perpendicular to each other. The first rotating seat 102 is mounted on the first vertical guide rail 101 through the first moving pair 2 12 and is connected to the moving platform 6 through the first universal joint 13; the second rotating seat 202 is mounted on the second vertical guide rail 201 through the second moving pair 22 and is connected to the moving platform 6 through the second universal joint 23; the third rotating seat 302 is mounted on the third vertical guide rail 301 through the third moving pair 2 32 and is connected to the moving platform 6 through the third universal joint 33.

[0026] Each universal joint is connected to the rotating seat and the movable platform 6 through the rotating joint 1 and the rotating joint 2, and the rotating axes of the rotating joint 1 and the rotating joint 2 are perpendicular to each other. In this embodiment, the universal joint comprises a T-shaped structure, wherein the horizontal rod of the T-shaped structure and the rotating seat constitute the rotating joint 1, and the vertical rod of the T-shaped structure and the movable platform 6 constitute the rotating joint 2. The structures of the three universal joints are the same, such as Figure 2 As shown, the structure of the universal joint in this application is described using the first universal joint 23 in the second branch chain 2 as an example. The second universal joint 23 includes: a second T-shaped structure 2301, the horizontal rod of the second T-shaped structure 2301 and the second rotating seat 202 forming a second rotating joint 231, a rotating connecting seat 601 provided on the edge of the movable platform 6, and the vertical rod of the second T-shaped structure 2301 and the rotating connecting seat 601 forming a second rotating joint 232.

[0027] In this application, three moving pairs: the first moving pair 12, the second moving pair 22 and the third moving pair 32 are set as driving pairs at the same time, and are driven by motors to realize the two rotations and one movement of the moving platform; the remaining moving pairs are follower pairs and do not require motor drive.

[0028] Based on the first movable joint 12, the second movable joint 22 and the third movable joint 32, the movable platform 6 can achieve one degree of freedom of movement. Based on the first universal joint 13, the second universal joint 23 and the third universal joint 33, two degrees of rotational freedom can be achieved. The rotational movement of the movable guide rail 5 relative to the fixed guide rail 4 can enable the mechanism to avoid accompanying movement, reduce the difficulty of control, and improve the accuracy of the movable platform movement.

[0029] Assumptions Figure 1 This is the initial status of this applicant organization. Figure 1In the state in, three driving motors are started to drive the first moving pair 2 12 downward along the first vertical guide rail 101, the second moving pair 22 upward along the second vertical guide rail 201, and the third moving pair 2 32 downward along the third vertical guide rail 301. As the vertical positions of the first moving pair 2 12, the second moving pair 22 and the third moving pair 2 32 change, the positions of the three moving pairs 1 change accordingly, that is: the first moving pair 11 moves along the fixed guide rail 4, the second moving pair 2 moves along the fixed guide rail 4, and the third moving pair 31 moves along the moving guide rail 5; at the same time, the angle between the moving guide rail 5 and the moving platform 6 also changes accordingly, as well as the angles between the first universal joint 13, the second universal joint 23 and the third universal joint 33 and the horizontal plane also change accordingly, thereby achieving the change in the angle and position of the moving platform 6, which is Figure 3 The effect in.

[0030] like Figure 1 and Figure 3 As shown, the first vertical guide rail 101 and the moving axis of the first moving pair 11 constitute a first branch plane, and the second vertical guide rail 201 and the moving axis of the second moving pair 21 constitute a second branch plane. The first branch plane and the second branch plane are both in the same plane, recorded as the first plane, and the first plane is perpendicular to the bottom surface.

[0031] The first branch of the parallel mechanism with a movable guide rail designed in this application can only move within the plane of the first branch, and the second branch can only move within the plane of the second branch; the plane of the first branch and the plane of the second branch are both within the first plane, limiting the motion center of the moving platform within the first plane; and the plane formed by the rotatable moving guide rail 5 and the third vertical guide rail 301 is always perpendicular to the bottom surface, so the intersection A of the first plane and the plane where the rotatable guide rail is located is always perpendicular to the bottom surface, and the intersection A is the trajectory of the motion center of the moving platform, so the motion of the motion center of the moving platform does not move in other directions, that is, there is no accompanying motion.

[0032] After using the technical solution of the present invention, the two-turn-one-shift parallel mechanism with movable guide rails without accompanying motion has the advantages of the general two-turn-one-shift parallel mechanism and eliminates the disadvantages of some mechanisms with accompanying motion; the directions of the two rotating shafts of the mechanism are simple and clear, and the drive pair is arranged closer to the moving platform, which can be controlled more conveniently and accurately, and can be more conveniently controlled; the rotational freedom and the movement freedom are decoupled, so that the mechanism has better posture adjustment capabilities; the lack of accompanying motion means that the mechanism shaft will not undergo unexpected movement after continuous rotation, the moving platform has higher movement accuracy, and the application range is also wider. In addition, the parallel mechanism in this application uses moving pairs in many places to reduce the number of rods in the mechanism to improve the rigidity of the mechanism and the smoothness of the movement.

Claims

1. A two-rotation and one-transfer parallel robot mechanism with a movable guide rail, comprising: Dynamic platform and three branches with the same structure; It is characterized in that it also includes: a fixed guide rail and a movable guide rail; The fixed guide rail and the movable guide rail are both arranged on the bottom plane, and the movable guide rail is connected to the fixed guide rail via a first rotating pair; The branch chain includes: a vertical guide rail, a rotating seat, a first moving pair, a second moving pair and a universal joint; The vertical guide rail is arranged perpendicular to the bottom plane; among the three vertical guide rails, two of the vertical guide rails are installed on the fixed guide rail through a moving pair, and one of the vertical guide rails is installed on the moving guide rail through a moving pair; The plane formed by the movable guide rail and the vertical guide rail connected thereto is perpendicular to the bottom plane, and intersects with the plane formed by the other two vertical guide rails on a line perpendicular to the bottom plane; the axes of the movable pair 1 and the movable pair 2 are perpendicular to each other; In each of the branch chains, the rotating seat is installed on the vertical guide rail through the second moving pair; the rotating seat is connected to the moving platform through the universal joint.

2. The two-rotation-one-transfer parallel robot mechanism with movable guide rails according to claim 1, characterized in that: The three moving pairs are configured as driving pairs.

3. The two-rotation-one-transfer parallel robot mechanism with movable guide rails according to claim 1, characterized in that: The universal joint is connected to the rotating seat via a first rotating joint, and is connected to the moving platform via a second rotating joint; and the rotating axes of the first rotating joint and the second rotating joint are perpendicular to each other.

4. The two-rotation-one-transfer parallel robot mechanism with movable guide rails according to claim 3, characterized in that: The universal joint comprises a T-shaped structure, wherein the horizontal rod of the T-shaped structure and the rotating seat constitute the first rotating joint, and the vertical rod of the T-shaped structure and the moving platform constitute the second rotating joint.

5. The two-rotation-one-transfer parallel robot mechanism with movable guide rails according to claim 1, characterized in that: The axes of the two moving pairs installed on the fixed guide rail are located on the same straight line.

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