Translation-rotation parallel mechanism with motion decoupling and position positive solution symbolization

Abstract

The invention relates to the technical field of mechanism science, in particular to a motion decoupling and position positive solution symbolization one-translation and one-rotation parallel mechanism which comprises a static platform and a movable platform, and a first simple branch chain and a second simple branch chain are connected between the static platform and the movable platform; the first simple branch chain is formed by connecting a first moving pair and a first rotating pair in series, and the second simple branch chain is composed of a second moving pair, a second rotating pair, a third rotating pair, a fourth rotating pair and a fifth rotating pair. Rotation of the movable platform around the axis of the first rotating pair is determined by input of the first moving pair and the second moving pair, motion decoupling is achieved, and a symbolic position positive solution is easy to obtain. The whole parallel mechanism is composed of seven kinematic pairs, the number of the kinematic pairs is relatively small, potential machining errors, assembling gaps and the number of abrasion points can be reduced, the error transmission path between the kinematic pairs can be reduced, errors accumulated on the movable platform can be reduced, and the output motion precision of the movable platform can be improved.

Description

Technical Field

[0001] This invention relates to the field of mechanism technology, and in particular to a translational-rotational parallel mechanism with motion decoupling and positive position symbolization. Background Technology

[0002] Parallel mechanisms have positive sign solutions (formulaic solutions), which are very beneficial for their workspace analysis, dimensional synthesis, real-time motion control, dynamic balance calculation and dynamic analysis. Currently, some motion decoupling translational-rotational parallel mechanisms have also emerged in the prior art, such as the translational-rotational device with two branches containing a feature chain and large normal angle zero coupling degree disclosed in Chinese Patent No. CN113319818A, and the translational-rotational platform with two branches containing a feature chain and large angle zero coupling degree disclosed in Chinese Patent No. CN113319815A. The aforementioned parallel mechanism consisting of one translation and one rotation consists of at least ten kinematic pairs (prismatic pairs, revolute pairs, or ball joints). The number of kinematic pairs required is relatively large, and each kinematic pair has assembly errors, machining errors, and wear. These errors are transmitted and amplified between branches, and eventually accumulate on the moving platform, resulting in poor accuracy of the moving platform's output motion. More seriously, the error transmission path of the parallel mechanism is relatively complex, and the kinematic pairs affect each other, making it difficult to improve the accuracy of the moving platform by supplementing the errors. Summary of the Invention

[0003] The technical problem to be solved by this invention is: in order to solve the problem that the existing parallel mechanism of translation and rotation consists of at least ten kinematic pairs (prismatic pairs, revolute pairs or ball pairs), which requires a large number of kinematic pairs, and each kinematic pair has assembly errors, processing errors and wear, etc., which are transmitted and amplified between branches, and finally all accumulated on the moving platform, resulting in poor accuracy of the motion output of the moving platform. The present invention provides a parallel mechanism of translation and rotation with decoupled motion and positive position symbolization.

[0004] The technical solution adopted by the present invention to solve its technical problem is: a translation-rotation parallel mechanism with motion decoupling and positive position symbolization, including a static platform and a moving platform, wherein a first simple branch and a second simple branch are connected between the static platform and the moving platform; The first simple branch is composed of a sliding joint and a rotating joint connected in series with their axes parallel to each other. The sliding joint is located on the stationary platform, and the rotating joint is located on the moving platform. The second simple branch consists of a series of sequentially connected sliding joint 2, rotating joint 2, rotating joint 3, rotating joint 4, and rotating joint 5. The axes of the sliding joint 2, rotating joint 2, and rotating joint 3 are parallel to each other. The sliding joint 2 is located on the stationary platform, and the rotating joint 5 is located on the moving platform. The axis of the fourth revolute joint is perpendicular to or parallel to the axis of the fifth revolute joint; The axis of the first sliding joint is perpendicular to the axis of the second sliding joint.

[0005] Furthermore, when the axes of the fourth and fifth revolute joints are parallel, the axis of the fourth revolute joint is perpendicular to the axis of the third revolute joint. Alternatively, when the axis of the fourth revolute joint and the axis of the fifth revolute joint are perpendicular; the axis of the fourth revolute joint and the axis of the third revolute joint are parallel to each other.

[0006] Furthermore, the first and second sliding joints are driving joints, and the moving platform can generate output motions of translation along the axis of the first sliding joint and rotation around the axis of the first sliding joint.

[0007] Furthermore, the axis of the first movable joint and the axis of the second movable joint are in the same horizontal plane.

[0008] The present invention also provides a translation-rotation parallel mechanism with motion decoupling and positive position symbolization, comprising a static platform and a moving platform, wherein a first simple branch and a second simple branch are connected between the static platform and the moving platform; The first simple branch is composed of a sliding joint and a rotating joint connected in series with their axes parallel to each other. The sliding joint is located on the stationary platform, and the rotating joint is located on the moving platform. The second simple branch consists of a sliding joint 2, a rotating joint 2, a rotating joint 3, a ball joint 1, and a ball joint 2 connected in series. The axes of the sliding joint 2, the rotating joint 2, and the rotating joint 3 are parallel to each other. The sliding joint 2 is set on the static platform, and the rotating joint 5 is set on the moving platform. The axis of the first sliding joint is perpendicular to the axis of the second sliding joint.

[0009] Furthermore, the first and second sliding joints are driving joints, and the moving platform can generate output motions of translation along the axis of the first sliding joint and rotation around the axis of the first sliding joint.

[0010] Furthermore, the first movable joint moves in a vertical direction, while the second movable joint moves in a horizontal direction.

[0011] The beneficial effects of this invention are as follows: The translational-rotational parallel mechanism of this invention, which features motion decoupling and symbolic positive position solution, has its moving platform whose translational motion is determined only by the input of prismatic joint one, and its rotation about the axis of prismatic joint one is determined only by the inputs of prismatic joint one and prismatic joint two. This decoupling of motion makes it easy to obtain symbolic positive position solutions, thereby facilitating and simplifying the kinematics, motion control, trajectory planning, and dynamic analysis of the mechanism. Furthermore, the parallel mechanism consists of seven kinematic joints, a relatively small number, which reduces the potential number of machining errors, assembly gaps, and wear points. It also reduces the error transmission path between kinematic joints, decreases the accumulated error on the moving platform, improves the output motion accuracy of the moving platform, and lowers costs. The probability of collisions between kinematic joints is reduced, effectively increasing the working space of the moving platform. Attached Figure Description

[0012] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0013] Figure 1 This is a schematic diagram of a translation-rotation parallel mechanism with motion decoupling and positive position symbolization in Embodiment 1; Figure 2 This is a schematic diagram of a translation-rotation parallel mechanism with motion decoupling and positive position symbolization in Embodiment 2; Figure 3 This is a schematic diagram of a translation-rotation parallel mechanism with motion decoupling and positive position symbolization in Embodiment 3; Figure 4 This is a schematic diagram of a translation-rotation parallel mechanism with motion decoupling and positive position symbolization in Example 4. In the diagram: 1. Moving platform; 2. Static platform; I. First simple branch; II. Second simple branch; P 11 , Moving sub-one, P 21 1. Move the second auxiliary vehicle; R 12 Rotating joint 1, R 22 Rotating joint two, R 23 Rotating joint three, R 24 Rotating joint four, R 25 5. Rotary joint; S 24 , ball vice one, S 25 Second ball. Detailed Implementation

[0014] The invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention in a schematic manner. Therefore, they only show the components relevant to the invention. Orientations and references (e.g., up, down, left, right, etc.) are only used to aid in the description of the features in the drawings. Therefore, the following specific embodiments are not intended to be restrictive, and the scope of the claimed subject matter is defined solely by the appended claims and their equivalents.

[0015] Example 1, such as Figure 1 As shown, a translation-rotation parallel mechanism with motion decoupling and positive position symbolization includes a static platform 2 and a moving platform 1, wherein a first simple branch I and a second simple branch II are connected between the static platform 2 and the moving platform 1. The first simple branch I consists of a sliding joint P with parallel axes. 11 and revolute joint R 12 Series connection, moving pair P 11 Set on static platform 2, mobile sub-P 11 axis and sliding joint P 11 The rotational joint R moves in the same direction. 12 Set on dynamic platform 1; The second simple branch II consists of sequentially connected locating joints IIP. 21 Rotating pair 2R 22 Rotating joint three R 23 Rotating pair four R 24 and rotating joint five R 25 Composition, the movable sub-P 21 The axis, the revolute joint R 22 The axis and the three-axis revolute joint 23 The axes are parallel to each other, and the sliding joint is P. 21 The axis and the sliding joint 2P 21 The moving direction is consistent, and the moving pair P 21 The rotating joint R is set on the static platform 2. 25 Set on dynamic platform 1; Mobile Sub-P 11 The axis and the sliding joint 2P 21 The axis is perpendicular; the four-axis revolute joint is perpendicular. 24 The axis and the five-axis revolute joint 25 The axes are parallel, and the four rotating joints are R. 24 The axis and the revolute joint R 23 The axes are perpendicular to each other; specifically, the sliding joint P 11 The axis is parallel to the X-axis direction, and the sliding joint P2 21 The axis is parallel to the Y-axis, and the X-axis, Y-axis, and Z-axis are all perpendicular to each other. The sliding joint is P.11 The axis and the sliding joint 2P 21 The axes of all parts are perpendicular to the Z-axis direction, and the sliding joint is P. 11 The axis and the sliding joint 2P 21 The axes are in the same horizontal plane; The moving pair P 11 and mobile secondary P 21 As a driving joint, the moving platform 1 can generate along the rotational joint -R 12 Translation of the axis and about the revolute joint R 12 The output motion of axis rotation; In this embodiment, the translational motion of the moving platform 1 in the Y-axis direction is only caused by the sliding joint P. 11 The input determines that the rotation of the moving platform 1 around the Y-axis is determined by the prismatic joint P. 11 Mobile secondary P 21 The axis determines the motion decoupling property, making it easy to obtain the symbolic positive position solution. This makes the kinematics, motion control and trajectory planning, and dynamic analysis of the mechanism easy and convenient. Moreover, the translational-rotational parallel mechanism in this embodiment consists of seven kinematic pairs (the seven kinematic pairs are: prismatic pair-P...). 11 Rotating joint R 12 Mobile secondary P 21 Rotating pair 2R 22 Rotating joint three R 23 Rotating pair four R 24 and rotating joint five R 25 With fewer overall kinematic pairs, the number of potential machining errors, assembly gaps, and wear points can be reduced. It can also reduce the error transmission path between kinematic pairs, reduce the accumulated error on the moving platform 1, improve the accuracy of the output motion of the moving platform, and reduce costs. The probability of collision between kinematic pairs is reduced, which can effectively increase the working space of the moving platform 1. This parallel mechanism can be used for various workpieces (e.g., fuselages and wings of large aircraft, blades of large wind turbines, etc.) for operation (grinding, riveting, spraying, etc.).

[0016] Example 2, as Figure 2 As shown, the difference between Embodiment 2 and Embodiment 1 is that the revolute joint four R 24 The axis and the five-axis revolute joint 25 The axis is perpendicular, and the four-axis rotating joint is R. 24 The axis and the revolute joint of the three R 23 The axes are parallel to each other and are all parallel to the Y-axis.

[0017] Example 3, as Figure 3 As shown, the difference between Example 3 and Example 1 is that: the moving pair P 11 Rotating joint R 12 Rotating pair four R24 and rotating joint five R 25 The axes of both are translated along the Z-axis, and the sliding pair P is... 21 Rotating pair 2R 22 and rotating joint three R 23 The axes are all parallel to the X-axis, and the Z-axis is the height direction. The output motion of the moving platform 1 is rotation around the Z-axis and translation along the Z-axis.

[0018] Example 4, as Figure 4 As shown, a translation-rotation parallel mechanism with decoupled motion and positive position symbolization includes a static platform 2 and a moving platform 1, with a first simple branch I and a second simple branch II connected between the static platform 2 and the moving platform 1. The first simple branch I consists of a sliding joint P with parallel axes. 11 and revolute joint R 12 The moving pair P is connected in series. 11 Set on static platform 2, mobile sub-P 11 axis and sliding joint P 11 The rotational joint R moves in the same direction. 12 Set on dynamic platform 1; The second simple branch II consists of sequentially connected locating joints IIP. 21 Rotating pair 2R 22 Rotating joint three R 23 , ball vice-S 24 and ball secondary S 25 Composition, the movable sub-P 21 The axis, the revolute joint R 22 The axis and the three-axis revolute joint 23 The axes are parallel to each other, and the sliding joint P2 21 Set on static platform 2, move secondary P 21 The axis and the sliding joint 2P 21 The moving directions are consistent, and the rotation joint R is five 25 Set on dynamic platform 1; The moving pair P 11 The axis and the sliding joint 2P 21 The axis is perpendicular.

[0019] The moving pair P 11 and mobile secondary P 21 As a driving joint, the moving platform 1 can generate along the rotational joint -R 12 Translation of the axis and about the revolute joint R 12 The output motion of the axis rotation.

[0020] Specifically, mobile sub-P 11The axis is parallel to the Z-axis direction, and the sliding joint P2 21 The axis is parallel to the X-axis, and the X-axis, Y-axis, and Z-axis are perpendicular to each other. The sliding joint is P. 11 The axis and the sliding joint 2P 21 The axes of all parts are perpendicular to the Y-axis; sliding joint P 11 The direction of movement is vertical, and the translating joint P2 21 The direction of movement is horizontal; In this embodiment, the translational motion of the moving platform 1 in the Y-axis direction is only caused by the sliding joint P. 11 The input determines that the rotation of the moving platform 1 around the Y-axis is determined by the prismatic joint P. 11 Mobile secondary P 21 The axis determines the motion decoupling property, making it easy to obtain the symbolic positive position solution. This makes the kinematics, motion control and trajectory planning, and dynamic analysis of the mechanism easy and convenient. Moreover, the translational-rotational parallel mechanism in this embodiment consists of seven kinematic pairs (the seven kinematic pairs are: prismatic pair-P...). 11 Rotating joint R 12 Mobile secondary P 21 Rotating pair 2R 22 Rotating joint three R 23 , ball vice-S 24 and ball secondary S 25 With fewer overall kinematic pairs, the number of potential machining errors, assembly gaps, and wear points can be reduced. It can also reduce the error transmission path between kinematic pairs, reduce the accumulated error on the moving platform 1, improve the accuracy of the output motion of the moving platform 1, and reduce costs. The probability of collision between kinematic pairs is reduced, which can effectively increase the working space of the moving platform 1. This parallel mechanism can be used for various workpieces (e.g., fuselage and wings of large aircraft, blades of large wind turbines, etc.) for operation (grinding, riveting, spraying, etc.).

[0021] The above description, based on the preferred embodiments of the present invention, provides inspiration. Those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification but must be determined according to the claims.

Claims

1. A translational-rotational parallel mechanism with decoupled motion and positive position symbolization, comprising a static platform (2) and a moving platform (1), characterized in that: The static platform (2) and the moving platform (1) are connected by a first simple branch (Ⅰ) and a second simple branch (Ⅱ); The first simple branch (Ⅰ) consists of a sliding joint (P) with mutually parallel axes. 11 ) and revolute joint 1 (R 12 The moving pair (P) is composed of multiple units connected in series. 11 The rotating pair (R) is set on the static platform (2). 12 ) Set on the dynamic platform (1); The second simple branch (Ⅱ) consists of sequentially connected mobilizing joints 2 (P) 21 ), Rotary joint two (R) 22 ), rotating joint three (R) 23 ), Rotary joint four (R) 24 ) and rotating joint five (R 25 Composed of, the second movable sub-pair (P) 21 The axis of the revolute joint (R) 22 The axis of the revolute joint and the third revolute joint (R) 23 The axes of the two moving pairs (P) are parallel to each other. 21 The rotating joint (R) is set on the static platform (2). 25 ) Set on the dynamic platform (1); The revolute joint four (R) 24 The axis of the revolute joint is perpendicular or parallel to the axis of the fifth revolute joint (R). 25 The axis of ) The moving pair one (P) 11 The axis of ) and the sliding joint 2 (P) 21 The axis is perpendicular to the axis.

2. The translation-rotation parallel mechanism with motion decoupling and positive position symbolization according to claim 1, characterized in that: The revolute joint four (R) 24 The axis of the revolute joint and the fifth revolute joint (R) 25 When the axes of the four revolute joints (R) are parallel, the four revolute joints (R) 24 The axis of the revolute joint (R) and the axis of the revolute joint (R) 23 The axes of the two axes are perpendicular to each other; Alternatively, the revolute joint four (R) 24 The axis of the revolute joint and the fifth revolute joint (R) 25 When the axis of the revolute joint is perpendicular; the fourth revolute joint (R) 24 The axis of the revolute joint and the three revolute joints (R) 23 The axes of the two axes are parallel to each other.

3. The translation-rotation parallel mechanism with motion decoupling and positive position symbolization according to claim 1, characterized in that: The moving pair one (P) 11 ) and moving secondary (P) 21 (1) is a driving pair, and the moving platform (1) can generate along the rotational joint (R) 12 Translation of the axis and about the revolute joint (R) 12 The output motion of the axis rotation.

4. The translation-rotation parallel mechanism with motion decoupling and positive position symbolization according to claim 3, characterized in that: The moving pair one (P) 11 The axis of ) and the sliding joint 2 (P) 21 The axes of the two planes are in the same horizontal plane.

5. A translational-rotational parallel mechanism with decoupled motion and positive position symbolization, comprising a static platform (2) and a moving platform (1), characterized in that: The static platform (2) and the moving platform (1) are connected by a first simple branch (Ⅰ) and a second simple branch (Ⅱ); The first simple branch (Ⅰ) consists of a sliding joint (P) with mutually parallel axes. 11 ) and revolute joint 1 (R 12 The moving pair (P) is composed of multiple units connected in series. 11 The rotating pair (R) is set on the static platform (2). 12 ) Set on the dynamic platform (1); The second simple branch (Ⅱ) consists of sequentially connected mobilizing joints 2 (P) 21 ), Rotary joint two (R) 22 ), rotating joint three (R) 23 ), Ball Vice One (S) 24 ) and ball secondary (S 25 Composed of, the second movable sub-pair (P) 21 The axis of the revolute joint (R) 22 The axis of the revolute joint and the third revolute joint (R) 23 The axes of the two moving pairs (P) are parallel to each other. 21 The rotating joint (R) is set on the static platform (2). 25 ) Set on the dynamic platform (1); The moving pair one (P) 11 The axis of ) and the sliding joint 2 (P) 21 The axis is perpendicular to the axis.

6. The translation-rotation parallel mechanism with motion decoupling and positive position symbolization according to claim 5, characterized in that: The moving pair one (P) 11 ) and moving secondary (P) 21 (1) is a driving pair, and the moving platform (1) can generate along the rotational joint (R) 12 Translation of the axis and about the revolute joint (R) 12 The output motion of the axis rotation.

7. The translation-rotation parallel mechanism with motion decoupling and positive position symbolization according to claim 6, characterized in that: The moving pair one (P) 11 The direction of movement of the second moving pair (P) is in the vertical direction. 21 The direction of movement is horizontal.

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