Two-movement and one-rotation complete decoupling parallel mechanism
By designing a fully decoupled parallel mechanism with two shifts and one turn, using three active branches and one constrained branch chain, the simple control of the dynamic platform is realized, solving the motion coupling and computational complexity of the existing parallel mechanism, and improving the Stiffness and practicality of the mechanism.
Patent Information
- Application Number
- CN202411373547.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-29
- Publication Date
- 2024-12-27
AI Technical Summary
Due to its strong motion coupling, difficulty in path planning and complex kinematic calculations, existing parallel mechanisms have difficulties in analyzing and computing, configuration design and mechanism control.
A two-shift and one-turn completely decoupled parallel mechanism is designed, including a fixed platform, a dynamic platform, three active branches arranged between the two and a constrained branch chain, and the movement of the dynamic platform is realized by driving the active sub-driven by the servo motor. ,具有完全解耦的运动学特性。
The mechanism realizes simple control of the dynamic platform, which is highly practical, solves the problems of strong coupling, complex kinematic calculations, and difficult path planning, and improves the rigidity and load-bearing capacity of the mechanism.
Smart Images
Figure CN119188697A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of parallel robots, and in particular relates to a two-movement-one-rotation fully decoupled parallel mechanism. Background Art
[0002] With the in-depth development of robotics technology, robots replacing humans will become the development direction of the future robotics field. As a branch of the robotics field, parallel robots have strong load capacity, high motion accuracy, and a wide variety of mechanisms. Therefore, parallel robot mechanisms have become a research hotspot in the field of mechanism science and even robotics.
[0003] The parallel mechanism is composed of multiple motion branches connecting the moving platform and the fixed platform. Compared with the serial mechanism, it has many advantages, such as good structural rigidity, small cumulative error and strong load-bearing capacity. It has been widely used in many fields such as aerospace, medical equipment, motion simulators, etc., such as the Delta mechanism used in high-speed sorting robots, the Stewart platform used in flight simulators, and the rope-type parallel mechanism used in the Sky Eye feed device.
[0004] Early parallel mechanisms were mostly six-DOF parallel mechanisms. In recent years, mechanisms with fewer DOF have become a hot topic of research, especially three-DOF mechanisms. Compared with multi-DOF parallel mechanisms, mechanisms with fewer DOF have the advantages of fewer driving parts, fewer components, easier control, and easier manufacturing. However, most parallel mechanisms are hindered in their promotion and application due to their strong motion coupling, difficult path planning, and complex kinematic calculations. Summary of the invention
[0005] The purpose of the present invention is to provide a two-shift one-rotation fully decoupled parallel mechanism to solve the difficulties in analytical calculation, configuration design and mechanism control caused by the strong coupling of the parallel mechanism existing in the prior art.
[0006] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a two-movement-one-rotation fully decoupled parallel mechanism, comprising a fixed platform, a moving platform, and a first active branch chain, a second active branch chain, a third active branch chain and a just-constrained branch chain arranged therebetween; The first active branch chain includes a first rotating pair, a first universal joint, a first moving pair and a second universal joint connected in sequence, the first rotating pair is connected to the fixed platform, and the second universal joint is connected to the moving platform; the rotation axis of the first universal joint includes the first universal joint inner axis and the first universal joint outer axis, the rotation axis of the second universal joint includes the second universal joint inner axis and the second universal joint outer axis, the axis of the first rotating pair is parallel to the first universal joint inner axis, the first universal joint outer axis is parallel to the second universal joint inner axis, and is perpendicular to the moving direction of the first moving pair; The second active branch chain includes a second rotating pair, a third universal joint, a second moving pair and a third rotating pair connected in sequence by a connecting rod, the second rotating pair is connected to the fixed platform, and the third rotating pair is connected to the moving platform; the rotation axis of the third universal joint includes a third universal joint inner axis and a third universal joint outer axis, the axis of the second rotating pair is parallel to the third universal joint inner axis, the third universal joint outer axis is parallel to the axis of the third rotating pair, and is perpendicular to the moving direction of the second moving pair; The third active branch chain includes a fourth rotating pair, a fourth universal joint, a third moving pair and a fifth universal joint which are sequentially connected by connecting rods, the fourth rotating pair is connected to the fixed platform, and the fifth universal joint is connected to the moving platform; the rotation axis of the fourth universal joint includes a fourth universal joint inner axis and a fourth universal joint outer axis, and the rotation axis of the fifth universal joint includes a fifth universal joint inner axis and a fifth universal joint outer axis; the axis of the fourth rotating pair is perpendicular to the fourth universal joint inner axis, the fourth universal joint outer axis is parallel to the fifth universal joint inner axis, and is perpendicular to the moving direction of the third moving pair; The just-constrained branch chain includes a fourth mobile pair and a cylindrical pair connected by a connecting rod, the fourth mobile pair and the cylindrical pair are connected to the fixed platform and the movable platform respectively, and the moving direction of the fourth mobile pair is perpendicular to the axis of the cylindrical pair; The axes of the first rotating pair, the second rotating pair and the fourth rotating pair are perpendicular to each other, and the axis of the second rotating pair is parallel to the moving direction of the fourth moving pair.
[0007] The first rotating pair, the second rotating pair and the fourth rotating pair are respectively active pairs of the active branch chains, and the active pairs are driven by corresponding driving mechanisms.
[0008] The driving mechanism is a servo motor.
[0009] The moving platform is a rectangular platform.
[0010] The second universal joint, the cylindrical pair and the third rotation pair are sequentially arranged along the length direction of the first side of the moving platform. The fifth universal joint is connected to the second side of the moving platform, and the second side is perpendicular to the first side.
[0011] The second universal joint outer axis, the axis of the third rotation pair, the fifth universal joint outer axis and the axis of the cylindrical pair are arranged in the same plane.
[0012] The outer axis of the second universal joint, the axis of the cylindrical pair and the axis of the third rotation pair are collinear and perpendicular to the outer axis of the fifth universal joint.
[0013] The connecting rods of the first active branch chain include a first connecting rod, a second connecting rod and a third connecting rod. The first connecting rod is used to connect the first rotating pair and the end where the first universal joint inner axis is located of the first universal joint. The second connecting rod and the third connecting rod slide relative to each other to form the first moving pair. The second connecting rod is connected to the end where the first universal joint outer axis is located of the first universal joint. The third connecting rod is connected to the end where the second universal joint inner axis is located of the second universal joint. The end where the second universal joint outer axis is located of the second universal joint is connected to the moving platform.
[0014] The connecting rods in the second active branch chain include a fourth connecting rod, a fifth connecting rod and a sixth connecting rod. The fourth connecting rod is used to connect the second rotating pair and the end where the third universal joint inner axis is located of the third universal joint. The fifth connecting rod and the sixth connecting rod slide relative to each other to form the second moving pair. The fifth connecting rod is connected to the end where the third universal joint outer axis is located of the third universal joint. The sixth connecting rod is connected to the third rotating pair.
[0015] The connecting rods in the third active branch chain include a seventh connecting rod, an eighth connecting rod and a ninth connecting rod. The seventh connecting rod is used to connect the fourth rotating pair and the end where the fourth universal joint inner axis of the fourth universal joint is located. The eighth connecting rod and the ninth connecting rod slide relative to each other to form the third moving pair. The eighth connecting rod is connected to the end where the fourth universal joint outer axis of the fourth universal joint is located. The ninth connecting rod is connected to the end where the fifth universal joint inner axis of the fifth universal joint is located. The end where the fifth universal joint outer axis of the fifth universal joint is located is connected to the moving platform.
[0016] The beneficial effects of the present invention are as follows: in the present invention, when the first rotating pair in the first active branch chain is input as an active pair alone, it can control one degree of freedom of movement of the moving platform, when the second rotating pair in the second active branch chain is input as an active pair alone, it controls another degree of freedom of movement of the moving platform, and when the fourth rotating pair in the third active branch chain is input as an active pair alone, it controls one degree of freedom of rotation of the moving platform, so the moving platform in the present invention has rotational motion around one direction and movement motion along two directions. The mechanism has completely decoupled kinematic characteristics, simple control, strong practicality, and solves the problems of strong coupling, complex kinematic calculation, and difficult path planning of general parallel mechanisms.
[0017] Moreover, the addition of just-constrained branches in the parallel mechanism significantly improves the stiffness, load-bearing capacity and stress conditions of the mechanism. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0019] Figure 1 It is a schematic diagram of the overall structure of the two-shift-one-rotation fully decoupled parallel mechanism of the present invention; Markings in the figure: 10, fixed platform, 20, moving platform; L1, first active branch, R 11 , the first rotation pair, U 12 , the first universal joint, R 121 , the inner axis of the first universal joint, R 122 , the outer axis of the first universal joint, P 13 , the first moving pair, U 14 , the second universal joint, R 141 , the inner axis of the second universal joint, R 142 , the second universal joint outer axis, 1-1, the first connecting rod, 1-2, the second connecting rod, 1-3, the third connecting rod; L2, the second active branch, R 21 , the second revolute pair, U 22 、The third universal joint, R 221 , inner axis of the third universal joint, R 222 , the outer axis of the third universal joint, P 23 , the second moving pair, R 24 , the third rotation pair, 2-1, the fourth connecting rod, 2-2, the fifth connecting rod, 2-3, the sixth connecting rod; L3, the third active branch, R 31 , the fourth rotation pair, U 32 , the fourth universal joint, R 321 , the inner axis of the fourth universal joint, R 322 , the outer axis of the fourth universal joint, P 33 , the third mobile pair, U 34 、Fifth universal joint, R 341 , inner axis of the fifth universal joint, R 342 , the outer axis of the fifth universal joint, 3-1, the seventh connecting rod, 3-2, the eighth connecting rod, 3-3, the ninth connecting rod; L4, just constrained branch, P 41 , the fourth mobile pair, C 42 , cylindrical pair, 4-1, tenth connecting rod. DETAILED DESCRIPTION
[0020] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments, but they are not intended to limit the invention in any way.
[0021] The two-movement-one-rotation fully decoupled parallel mechanism described in the present invention includes a fixed platform 10, a moving platform 20 and four motion chains arranged therebetween for realizing the two-movement-one-rotation motion of the moving platform 20, including three active branch chains and one just-constrained branch chain L4, and the three active branch chains are respectively a first active branch chain L1, a second active branch chain L2 and a third active branch chain L3.
[0022] The first active branch chain L1 includes a rotation pair, a translation pair and two universal joints, which are the first rotation pair R and the second translation pair R in the order from the fixed platform 10 to the moving platform 20. 11 、The first universal hinge U 12 , the first moving pair P 13 And the second universal joint U 14 Among them, the first universal joint U 12 The two rotation axes include the first universal joint inner axis R 121 and the first universal joint outer axis R 122 , the second universal joint U 14 Including the second universal joint inner axis R 141 and the second universal joint outer axis R 142 . The first rotation pair R 11 One end of the first rotation pair R is connected to the fixed platform 10. 11 The other end is connected to the first universal joint U through the first connecting rod 1-1 12 One end is connected to the first universal joint U 12 The other end passes through the first moving pair P 13 With the second universal joint U 14 One end is connected to the second universal joint U 14 The other end of the first moving pair P is connected to the moving platform 20. 13 The first universal joint inner axis R is formed by slidingly connecting the second connecting rod 1-2 and the third connecting rod 1-3. 121 The second connecting rod 1-2 is connected to the outer axis R of the first universal joint. 122 The third connecting rod 1-3 is connected to the inner axis R of the second universal joint. 141 The second universal joint outer axis R 142 The end is connected to the moving platform 20. Further, the first rotation pair R 11 The axis of the first universal joint is 121 Parallel to the outer axis R of the first universal joint 122 With the second universal joint inner axis R 141 Parallel to the first moving pair P 13 The direction of movement is vertical.
[0023] The second active branch chain L2 includes two rotational pairs, a universal joint and a translation pair, which are the second rotational pairs R and R in the order from the fixed platform 10 to the moving platform 20. 21 、Third universal joint U 22 , the second moving pair P 23 and the third rotation pair R 24 , where the third universal joint U 22 The two rotation axes are the inner axis R of the third universal joint 221 and the third universal joint outer axis R 222 . The second rotation pair R 21 One end of the second rotation pair R is connected to the fixed platform 10. 21 The other end is connected to the third universal joint U through the fourth connecting rod 2-1 22 One end is connected to the third universal joint U 22 The other end passes through the second moving pair P 23 With the third rotation pair R 24 One end of the third rotation pair R 24 The other end of the second moving pair P is connected to the moving platform 20. 23 The fourth connecting rod 2-1 is connected to the inner axis R of the third universal joint by sliding connection with the fifth connecting rod 2-2 and the sixth connecting rod 2-3. 221 The fifth connecting rod 2-2 is connected to the outer axis R of the third universal joint. 222 Further, the second rotation pair R 21 The axis of the third universal joint is 221 Parallel to the outer axis R of the third universal joint 222 With the third rotation pair R 24 The axis is parallel to the second moving pair P 23 The direction of movement is vertical.
[0024] The third active branch chain L3 has the same structure as the first active branch chain L1, including a rotation pair, a translation pair and two universal joints. The fourth rotation pair R 31 、The fourth universal hinge U 32 , the third mobile pair P 33 And the fifth universal joint U 34 , where the fourth universal joint U 32 The two rotation axes are the fourth universal joint inner axis R 321 and the fourth universal joint outer axis R 322 , the fifth universal joint U 34 The two rotation axes are the inner axis R of the fifth universal joint 341 and the outer axis R of the fifth universal joint 342 The fourth rotation pair R 31One end is connected to the fixed platform 10, and the other end is connected to the fourth universal joint U through the seventh connecting rod 3-1. 32 One end is connected to the fourth universal joint U 32 The other end passes through the third moving pair P 33 With the fifth universal joint U 34 One end is connected to the fifth universal joint U 34 The other end of the third moving pair P is connected to the moving platform 20. 33 The seventh connecting rod 3-1 is connected to the inner axis R of the fourth universal joint. 321 The eighth connecting rod 3-2 is connected to the outer axis R of the fourth universal joint. 322 The ninth connecting rod 3-3 is connected to the inner axis R of the fifth universal joint 341 The end connection, the fifth universal joint outer axis R 342 The end is connected to the moving platform 20. Further, the fourth rotation pair R 31 The axis of the fourth universal joint is 321 Vertical, fourth universal joint outer axis R 322 With the inner axis R of the fifth universal joint 341 Parallel to the third moving pair P 33 The direction of movement is vertical.
[0025] The just-constrained branch chain L4 includes a fourth moving pair P 41 and cylindrical pair C 42 , the fourth mobile pair P 41 One end and the cylindrical pair C 42 One end of each of the fourth movable pair P is directly connected to the fixed platform 10 and the movable platform 20. 41 Through the tenth connecting rod 4-1 and the cylindrical pair C 42 Among them, the fourth mobile pair P 41 The moving direction of the cylindrical pair C 42 The axis is vertical.
[0026] In this embodiment, the first rotation pair R in the first active branch chain L1 11 The axis of the second active branch chain L2 and the second revolute pair R 21 The axis and the fourth rotation pair R in the third active branch chain L3 31 The axes of the three are mutually perpendicular, and the second revolving pair R in the second active branch chain L2 21 The axis of the fourth moving pair P in the just constrained branch chain L4 41 Parallel to the direction of movement.
[0027] Further optimizing this solution, the outer axis R of the second universal joint in the first active branch chain L1 142, the third rotation pair R in the second active branch chain L2 24 The axis of the fifth universal joint in the third active branch chain L3 342 And the cylindrical pair C in the just-constrained branch chain L4 42 The four axes are arranged in the same plane, and the second universal joint outer axis R in the first active branch chain L1 142 , the cylindrical pair C in the branch chain L4 is just constrained 42 The axis and the third rotation pair R in the second active branch chain L2 24 The three axes are parallel and distributed on the same straight line, and are connected to the outer axis R of the fifth universal joint in the third active branch chain L3. 342 Vertical setting.
[0028] The moving platform is a rectangular platform, and the second universal joint U in the first active branch chain L1 14 , the cylindrical pair C in the branch chain L4 is just constrained 42 and the third rotation pair R in the second active branch chain L2 24 The fifth universal joint U in the third active branch chain L3 is sequentially arranged along the length direction of the first side of the moving platform 20. 34 The second side edge is connected to the moving platform 20 , and the second side edge is perpendicular to the first side edge.
[0029] In the above parallel mechanism, the first rotating pair R in the first active branch chain L1 11 is the active pair of the first active branch chain L1, and the second rotation pair R in the second active branch chain L2 21 is the active pair of the second active branch chain L2, and the fourth rotation pair R in the third active branch chain L3 31 The active pair of the third active branch chain L3 is driven by the driving mechanism to drive the active pairs of the three active branches respectively, so that the moving platform can achieve one rotation and two movement in space. The driving mechanism is a servo motor.
[0030] The control principle of the present invention is as follows: the present invention drives the active pair through the servo motor, and provides power to the moving platform 20 through three active branch chains. The first driving motor drives the first rotating pair R in the first active branch chain L1. 11 , so that the moving platform 20 moves along the fourth moving pair P in the fourth active branch chain L4 41 The second driving motor drives the second rotating pair R in the second active branch chain L2. 21 , so that the moving platform 20 is along the cylindrical pair C in the constrained branch chain L4 42 The third driving motor drives the fourth rotating pair R in the third active branch chain L3. 31 , so that the moving platform 20 is just constrained by the cylindrical pair C in the branch chain L4 42The parallel mechanism rotates in the axial direction, thereby realizing the three-degree-of-freedom movement of one rotation and two movements in space.
[0031] The above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Those skilled in the art should understand that the specific implementation modes of the present invention may be modified or replaced by equivalents with reference to the above embodiments. Any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention are within the scope of protection of the pending claims.
Claims
1. A two-movement-one-rotation fully decoupled parallel mechanism, comprising a fixed platform (10), a moving platform (20), and a first active branch chain (L1), a second active branch chain (L2), a third active branch chain (L3), and a just-constrained branch chain (L4) arranged therebetween, characterized in that: The first active branch chain (L1) includes a first rotating pair (R 11 )、First universal joint(U 12 )、The first moving pair(P 13 ) and the second universal joint (U 14 ), the first rotation pair (R 11 ) is connected to the fixed platform (10), and the second universal joint (U 14 ) is connected to the moving platform (20); the first universal joint (U 12 ) includes the first universal joint inner axis (R 121 ) and the first universal joint outer axis (R 122 ), the second universal joint (U 14 ) includes the second universal joint inner axis (R 141 ) and the outer axis of the second universal joint (R 142 ), the first rotation pair (R 11 ) and the first universal joint inner axis (R 121 ) parallel to the outer axis of the first universal joint (R 122 ) and the inner axis of the second universal joint (R 141 ) and is parallel to the first moving pair (P 13 ) is moving in a vertical direction; The second active branch chain (L2) includes a second revolute pair (R 21 )、Third universal joint(U 22 )、The second moving pair(P 23 ) and the third rotation pair (R 24 ), the second rotation pair (R 21 ) is connected to the fixed platform (10), the third rotation pair (R 24 ) is connected to the moving platform (20); the third universal joint (U 22 ) includes the third universal joint inner axis (R 221 ) and the third universal joint outer axis (R 222 ), the second rotation pair (R 21 ) and the inner axis of the third universal joint (R 221 ) parallel to the outer axis of the third universal joint (R 222 ) and the third rotation pair (R 24 ) and is parallel to the axis of the second moving pair (P 23 ) is moving in a vertical direction; The third active branch chain (L3) includes a fourth rotation pair (R 31 )、The fourth universal joint (U 32 )、The third moving pair(P 33 ) and the fifth universal joint (U 34 ), the fourth rotation pair (R 31 ) is connected to the fixed platform (10), the fifth universal joint (U 34 ) is connected to the moving platform (20); the fourth universal joint (U 32 ) includes the fourth universal joint inner axis (R 321 ) and the fourth universal joint outer axis (R 322 ), the fifth universal joint (U 34 ) includes the fifth universal joint inner axis (R 341 ) and the outer axis of the fifth universal joint (R 342 ); The fourth rotation pair (R 31 ) and the inner axis of the fourth universal joint (R 321 ) vertical, the fourth universal joint outer axis (R 322 ) and the inner axis of the fifth universal joint (R 341 ) and is parallel to the third moving pair (P 33 ) is moving in a vertical direction; The constrained branch (L4) includes a fourth moving joint (P 41 ) and cylindrical pair (C 42 ), the fourth mobile pair (P 41 ) and cylindrical pair (C 42 ) are respectively connected to the fixed platform (10) and the moving platform (20), the fourth moving pair (P 41 ) and the moving direction of the cylindrical pair (C 42 )’s axis is vertical; The first rotation pair (R 11 ) axis, the second revolute pair (R 21 ) axis and the fourth rotation pair (R 31 ) are perpendicular to each other, and the second revolute pair (R 21 ) and the axis of the fourth movable pair (P 41 )’s direction of movement.
2. The two-shift-one-rotation fully decoupled parallel mechanism according to claim 1, characterized in that: The first rotation pair (R 11 )、The second rotation pair(R 21 ) and the fourth rotation pair (R 31 ) are respectively the active pairs of the active branch chains, and the active pairs are driven by the corresponding driving mechanisms.
3. The two-shift-one-rotation fully decoupled parallel mechanism according to claim 2, characterized in that: The driving mechanism is a servo motor.
4. The two-shift-one-rotation fully decoupled parallel mechanism according to claim 1, characterized in that: The moving platform (20) is a rectangular platform.
5. The two-shift-one-rotation fully decoupled parallel mechanism according to claim 4, characterized in that: The second universal joint (U 14 ), the cylindrical pair (C 42 ) and the third rotation pair (R 24 ) are sequentially arranged along the length direction of the first side of the moving platform (20), and the fifth universal joint (U 34 ) is connected to a second side edge of the moving platform (20), and the second side edge is perpendicular to the first side edge.
6. The two-shift-one-rotation fully decoupled parallel mechanism according to claim 5, characterized in that: The second universal joint outer axis (R 142 ), the third rotation pair (R 24 ) axis, the outer axis of the fifth universal joint (R 342 ) and the cylindrical pair (C 42 ) are arranged in the same plane.
7. The two-shift-one-rotation fully decoupled parallel mechanism according to claim 6, characterized in that: The second universal joint outer axis (R 142 ), the cylindrical pair (C 42 ) axis and the third revolute pair (R 24 ) and is co-linear with the outer axis of the fifth universal joint (R 342 )vertical.
8. The two-shift-one-rotation fully decoupled parallel mechanism according to any one of claims 1 to 7, characterized in that: The connecting rods in the first active branch chain (L1) include a first connecting rod (1-1), a second connecting rod (1-2) and a third connecting rod (1-3), wherein the first connecting rod (1-1) is used to connect the first rotation pair (R 11 ) and the first universal joint (U 12 ) of the first universal joint inner axis (R 121 ) at the end where the second connecting rod (1-2) and the third connecting rod (1-3) slide relative to each other to form the first moving pair (P 13 ), the second connecting rod (1-2) and the first universal joint (U 12 ) of the first universal joint outer axis (R 122 ) is connected to the end where the third connecting rod (1-3) is connected to the second universal joint (U 14 ) of the second universal joint inner axis (R 141 ) is connected at the end, the second universal joint (U 14 ) of the second universal joint outer axis (R 142 ) is connected to the moving platform (20).
9. The two-shift-one-rotation fully decoupled parallel mechanism according to any one of claims 1 to 7, characterized in that: The connecting rods in the second active branch chain (L2) include a fourth connecting rod (2-1), a fifth connecting rod (2-2) and a sixth connecting rod (2-3), wherein the fourth connecting rod (2-1) is used to connect the second rotation pair (R 21 ) and the third universal joint (U 22 ) of the third universal joint inner axis (R 221 ) at the end where the fifth connecting rod (2-2) and the sixth connecting rod (2-3) slide relative to each other to form the second moving pair (P 23 ), the fifth connecting rod (2-2) and the third universal joint (U 22 ) of the third universal joint outer axis (R 222 ) is connected to the end where the sixth connecting rod (2-3) is connected to the third revolute pair (R 24 )connect.
10. The two-shift-one-rotation fully decoupled parallel mechanism according to any one of claims 1 to 7, characterized in that: The connecting rods in the third active branch chain (L3) include a seventh connecting rod (3-1), an eighth connecting rod (3-2) and a ninth connecting rod (3-3), wherein the seventh connecting rod (3-1) is used to connect the fourth rotation pair (R 31 ) and the fourth universal joint (U 32 ) of the fourth universal joint inner axis (R 321 ) at the end, the eighth connecting rod (3-2) and the ninth connecting rod (3-3) slide relative to each other to form the third moving pair (P 33 ), the eighth connecting rod (3-2) and the fourth universal joint (U 32 ) of the fourth universal joint outer axis (R 322 ) is connected to the end where the ninth connecting rod (3-3) is connected to the fifth universal joint (U 34 ) of the fifth universal joint inner axis (U 341 ) is connected at the end, the fifth universal joint (U 34 ) of the fifth universal joint outer axis (R 342 ) is connected to the moving platform (20).