A motion mechanism of a redundantly driven planar two-degree-of-freedom parallel polishing robot

Abstract

The present invention relates to the field of robotics. The purpose is to provide a redundantly driven planar two-degree-of-freedom parallel grinding robot, which should have the advantages of simple structure, high rigidity, and no singularity. The technical solution is a motion mechanism of a redundantly driven planar two-degree-of-freedom parallel grinding robot, characterized in that: the parallel mechanism includes a moving platform and a first branch, a second branch, and a third branch connected in parallel between the frame and the moving platform; the first branch includes a first guide rail, a first slider, and a second connecting rod and a third connecting rod connected in parallel at both ends through a rotating pair respectively; the second connecting rod and the third connecting rod are equal in length and arranged in parallel with each other; the axes of the rotating pair are parallel to each other and perpendicular to the axis of the first guide rail.

Description

Technical Field

[0001] The invention relates to the technical field of robots, in particular to a motion mechanism of a redundantly driven planar two-degree-of-freedom parallel polishing robot. Background Art

[0002] It is well known that the environment in the grinding workshop is bad; robot grinding is beneficial to people's physical and mental health, improves the production efficiency of the factory in the grinding process, improves product quality, reduces work intensity, enhances the competitiveness of the factory, and promotes industrial transformation and upgrading, which is more conducive to improving the automation level of social production as a whole. However, due to the irregularity of the grinding workpiece and the complexity of the process requirements, the requirements for industrial robot grinding applications are also very strict; in order to obtain good grinding accuracy, there are also high requirements for the rigidity of the robot.

[0003] Most of the robots currently used in grinding operations are serial robots (e.g. CN111421435A, CN111086013A). These robots have good flexibility, but have shortcomings such as error accumulation, low precision, and poor structural rigidity. A small number of robots use parallel robots such as (CN211029473U), which have the advantages of easy adjustment and use, high rigidity, but have disadvantages such as small space and singularity. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies of the above-mentioned background technology and provide a redundantly driven planar two-degree-of-freedom parallel grinding robot, which should have the advantages of simple structure, high rigidity, and no singularity.

[0005] The technical solution of the present invention is:

[0006] A motion mechanism of a redundantly driven planar two-degree-of-freedom parallel grinding robot, comprising a parallel mechanism, a grinding mechanism mounted on a moving platform, and a frame; the characteristics are:

[0007] The parallel mechanism comprises a moving platform and a first branch, a second branch and a third branch connected in parallel between the frame and the moving platform; the first branch comprises a first guide rail, a first slider, and a second connecting rod and a third connecting rod connected in parallel at both ends through a rotating pair respectively; the second connecting rod and the third connecting rod are of equal length and arranged in parallel with each other; the axes of the rotating pair are parallel to each other and perpendicular to the axis of the first guide rail;

[0008] The second branch includes a second guide rail, a second slider, a fifth rotation pair, a first connecting rod and a sixth rotation pair connected in sequence between the frame and the moving platform; the first connecting rod axis, the second connecting rod axis and the third connecting rod axis are in the same motion plane; the above-mentioned rotation pair axes are parallel to each other and perpendicular to the second guide rail axis; the second guide rail is replaced by the first guide rail or the second guide rail axis is colinear with the first guide rail axis and connected as a whole; the first connecting rod and the second connecting rod are equal in length; or,

[0009] The second branch has the same structure as the first branch and is replaced by the first branch, and the axes of the guide rails in the two branches are collinear and connected as one;

[0010] The third branch includes a third guide rail, a third slider, a second Hooke's joint, a fourth connecting rod, and a first Hooke's joint which are sequentially connected between the frame and the moving platform;

[0011] In the first branch and the second branch, all connecting rod axes are in the same motion plane.

[0012] In the first branch and the second branch, all rotational secondary axes of the two branches are parallel to each other and perpendicular to the movement secondary axis.

[0013] The first slider and the first guide rail cooperate to form a first moving pair, the second slider and the second guide rail cooperate to form a second moving pair, and the third slider and the third guide rail cooperate to form a third moving pair.

[0014] The axis of the rotating shaft connecting the second Hooke's joint and the third slider is parallel to the axis of the rotating shaft connecting the first Hooke's joint and the moving platform and is also parallel to the third moving secondary axis; the axis of the rotating shaft connecting the fourth connecting rod and the second Hooke's joint is parallel to the axis of the rotating shaft connecting the fourth connecting rod and the first Hooke's joint.

[0015] The grinding mechanism is located directly below the moving platform, and the center line of the grinding mechanism is perpendicular to the plane of the moving platform.

[0016] The beneficial effects of the present invention are: due to the use of redundant drive, a parallel four-link structure and a structure in which three sliders are parallel to each other, the mechanism has the advantages of large working space, good rigidity, no singularity, simple structure, low manufacturing cost, easy control, etc.; it is particularly suitable for use in the field of industrial grinding. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the three-dimensional structure of the first embodiment of the present invention.

[0018] Figure 2 It is a schematic diagram of the three-dimensional structure of the second embodiment of the present invention.

[0019] Figure 3It is a schematic diagram of the three-dimensional structure of the first branch in Example 1 and Example 2.

[0020] Figure 4 It is a schematic diagram of the three-dimensional structure of the second branch in the first embodiment.

[0021] Figure 5 It is a schematic diagram of the three-dimensional structure of the third branch in the first embodiment and the second embodiment.

[0022] In the figure: 1. grinding mechanism, 2. moving platform, 3. first slider, 4. second slider, 5. third slider, 6. first guide rail, 7. third guide rail, 8. first connecting rod, 9. second connecting rod, 10. third connecting rod, 11. fourth connecting rod, 12. first Hooke's hinge, 13. second Hooke's hinge. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with the accompanying drawings, but the present invention is not limited to the following embodiments.

[0024] Embodiment 1:

[0025] Figure 1 , Figure 3 , Figure 4 , Figure 5 The motion mechanism of the redundantly driven planar two-degree-of-freedom parallel grinding robot shown includes a parallel mechanism, a grinding mechanism 1 mounted on a moving platform 2, and a frame (omitted in the figure);

[0026] The parallel mechanism includes a first branch, a second branch and a third branch connected in parallel between the frame and the moving platform. The first branch includes a first guide rail 6, a first slider 3 (the first guide rail and the first slider cooperate to form a first moving pair) connected in sequence between the frame and the moving platform, and a second connecting rod 9 and a third connecting rod 10 connected in parallel at both ends through a rotating pair;

[0027] Wherein: the first guide rail is fixed to the frame; the rotating pair includes the first rotating pair (that is, the rotating pair connecting the second connecting rod and the first slider), the second rotating pair (that is, the rotating pair connecting the third connecting rod and the first slider), the third rotating pair (that is, the rotating pair connecting the second connecting rod and the moving platform), and the fourth rotating pair (that is, the rotating pair connecting the third connecting rod and the moving platform); the axes of these four rotating pairs are parallel to each other and are also perpendicular to the axis of the first moving pair.

[0028] The second branch includes a second guide rail, a second slider 4 (the second guide rail and the second slider cooperate to form a second moving pair), a fifth rotation pair, a first connecting rod 8 and a sixth rotation pair, which are sequentially connected between the frame and the moving platform 2;

[0029] Wherein: the second guide rail is fixed to the frame; the fifth rotation secondary axis (i.e. the rotation secondary axis connecting the first connecting rod and the second slider) and the sixth rotation secondary axis (i.e. the rotation secondary axis connecting the first connecting rod and the second slider) are parallel to each other and are also perpendicular to the second movable secondary axis.

[0030] The third branch includes a second guide rail 7, a third slider 5 (i.e., the second guide rail and the third slider cooperate to form a third moving pair), a second Hooke's joint 13, a fourth connecting rod 11, and a first Hooke's joint 12, which are sequentially connected between the frame and the moving platform;

[0031] Among them: the second guide rail is fixed to the frame; the axis of the rotating shaft connecting the second Hooke's hinge and the third slider is parallel to the axis of the rotating shaft connecting the first Hooke's hinge and the moving platform and is also parallel to the third moving secondary axis; the axis of the rotating shaft connected to the fourth connecting rod and the second Hooke's hinge is parallel to the axis of the rotating shaft connected to the fourth connecting rod and the first Hooke's hinge.

[0032] In the first branch and the second branch: the axis of the first guide rail is collinear with the axis of the second guide rail and the two guide rails are connected as one (or the first guide rail replaces the second guide rail); the second connecting rod, the third connecting rod, the first slider and the moving platform in the first branch form a parallel four-bar linkage (that is, the second connecting rod and the third connecting rod are equal in length and are arranged parallel to each other); all the connecting rods in the two branches are of equal length, and the axes of the connecting rods in the two branches are in the same motion plane.

[0033] In this embodiment, the moving platform has two degrees of freedom, horizontal and vertical. The driving pair of the parallel mechanism is the moving pair on each branch chain, and the driving method can be a ball screw driven by a motor (omitted in the figure); when the driving pair moves, it drives the first slider, the second slider, and the third slider, and the grinding mechanism (existing technology, no longer described in detail) can be driven by the moving platform to move in space to complete the grinding task.

[0034] Embodiment 2:

[0035] Figure 2 , Figure 3 , Figure 5 The motion mechanism of the redundantly driven planar two-degree-of-freedom parallel grinding robot shown comprises a parallel mechanism, a grinding mechanism 1 mounted on a moving platform 2, and a frame; and is characterized in that:

[0036] The parallel mechanism includes two first branches and one third branch connected in parallel between the frame and the moving platform. The structure of the second embodiment is similar to that of the first embodiment, except that the second branch in the first embodiment is now replaced by the first branch, and the axes of the guide rails in the two first branches are collinear and connected as one.

[0037] In the two first branches: the two first rotational sub-axes, the two second rotational sub-axes, the two third rotational sub-axes and the two fourth rotational sub-axes are parallel to each other; there is a parallel four-bar linkage in each branch, and the axes of the connecting rods in the two branches are in the same motion plane. Obviously, compared with embodiment 1, the structure of embodiment 2 is more stable and can withstand a larger load.

Claims

1. A motion mechanism of a redundantly driven planar two-degree-of-freedom parallel grinding robot, comprising a parallel mechanism, a grinding mechanism (1) mounted on a moving platform (2), and a frame; characterized in that: The parallel mechanism comprises a first branch, a second branch and a third branch connected in parallel between the frame and the moving platform; the first branch comprises a first guide rail (6) and a first slider (3) connected in sequence between the frame and the moving platform, and a second connecting rod (9) and a third connecting rod (10) connected in parallel at both ends through a rotating pair; the second connecting rod and the third connecting rod are of equal length and arranged in parallel with each other; the axes of the rotating pairs are parallel to each other and perpendicular to the axis of the first guide rail; The second branch comprises a second guide rail, a second slider (4), a fifth rotation pair, a first connecting rod (8) and a sixth rotation pair which are sequentially connected between the frame and the moving platform (2); the axis of the first connecting rod and the axis of the second connecting rod (9) and the axis of the third connecting rod (10) are in the same motion plane; the axes of the rotation pairs are parallel to each other and perpendicular to the axis of the second guide rail; the second guide rail is replaced by the first guide rail or the axis of the second guide rail is colinear with the axis of the first guide rail and connected as a whole; the first connecting rod and the second connecting rod are of equal length; or, The second branch has the same structure as the first branch and can be replaced by the first branch, and the axes of the guide rails in the two branches are collinear and connected as one; The third branch comprises a third guide rail (7), a third slider (5), a second Hooke's joint (13), a fourth connecting rod (11), and a first Hooke's joint (12) which are sequentially connected between the frame and the moving platform (2).

2. The motion mechanism of the redundantly driven planar two-degree-of-freedom parallel polishing robot according to claim 1, characterized in that: In the first branch and the second branch, all connecting rod axes are in the same motion plane.

3. The motion mechanism of the redundantly driven planar two-degree-of-freedom parallel polishing robot according to claim 1 or 2, characterized in that: In the first branch and the second branch, all rotational secondary axes of the two branches are parallel to each other and perpendicular to the movement secondary axis.

4. The motion mechanism of the redundantly driven planar two-degree-of-freedom parallel polishing robot according to claim 3 is characterized in that: The first slider and the first guide rail cooperate to form a first moving pair, the second slider and the second guide rail cooperate to form a second moving pair, and the third slider and the third guide rail cooperate to form a third moving pair.

5. The motion mechanism of the redundantly driven planar two-degree-of-freedom parallel polishing robot according to claim 4 is characterized in that: The axis of the rotating shaft connecting the second Hooke's joint and the third slider is parallel to the axis of the rotating shaft connecting the first Hooke's joint and the moving platform and is also parallel to the third moving secondary axis; the axis of the rotating shaft connecting the fourth connecting rod and the second Hooke's joint is parallel to the axis of the rotating shaft connecting the fourth connecting rod and the first Hooke's joint.

6. The motion mechanism of the redundantly driven planar two-degree-of-freedom parallel polishing robot according to claim 5, characterized in that: The grinding mechanism is located directly below the moving platform, and the center line of the grinding mechanism is perpendicular to the plane of the moving platform.

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