CN110778869A

CN110778869A - Two-dimensional motion platform

Info

Publication number: CN110778869A
Application number: CN201911104947.6A
Authority: CN
Inventors: 程方; 邹景武; 王寅; 叶瑞芳; 余卿
Original assignee: Huaqiao University
Current assignee: Huaqiao University
Priority date: 2019-11-13
Filing date: 2019-11-13
Publication date: 2020-02-11

Abstract

The invention provides a two-dimensional motion platform which comprises a carrying plate, a driving module, a supporting module and a control module, wherein the carrying plate is horizontally arranged, the driving module is used for driving the carrying plate to move, the supporting module is used for supporting the carrying plate, the control module is used for controlling the driving module to move, the carrying plate is horizontally arranged above the driving module and the supporting module, the carrying plate is rigidly connected with the driving module, and the carrying plate is flexibly hinged with the supporting module. The differential system is formed by arranging the two guide modules of the driving module and the supporting module, so that the motion stroke is effectively improved under the condition of ensuring the motion precision, and high precision and large stroke can be realized simultaneously. Simultaneously modularizing all parts of the motion platform according to functions, and modularizing the motion guide element into a driving module and a supporting module; the working carrying plane of the motion platform is modularized into a carrying plate part, each module is a universal component, the number of the partial modules can be increased or decreased as required, and secondary development flexibility is good.

Description

Two-dimensional motion platform

Technical Field

The invention relates to a precision platform, in particular to a two-dimensional motion platform.

Background

The high-precision two-dimensional motion platform is widely applied to various high-precision measurement and processing systems, such as three-coordinate measuring machines, microscopes, surface profilers, photoetching machines, 3D printing equipment and the like.

In order to meet the requirement of high precision, the conventional two-dimensional motion platform usually needs to sacrifice the moving stroke, the motion precision of the two-dimensional motion platform depends heavily on high-precision reference elements such as guide rails and guide planes, and an over-constrained system is easily formed by introducing a large number of guide elements.

In addition, most of the existing two-dimensional motion platforms adopt a self-contained design, and after the platforms are put into use, a user is difficult to change the structure of the platform, so that the secondary development flexibility of the system is greatly limited by the characteristic.

In view of the above, the applicant has conducted an intensive study on the structure of a high-precision two-dimensional motion platform, and has generated the present application.

Disclosure of Invention

The invention aims to provide a two-dimensional motion platform capable of realizing high precision and large stroke at the same time.

In order to achieve the purpose, the invention adopts the following technical scheme:

the utility model provides a two-dimensional motion platform, including the horizontal year thing board of arranging, be used for the drive module that the thing board removed, be used for supporting the support module of thing board and be used for controlling the control module of drive module motion, it is arranged to carry the thing board horizontal drive the drive module with the top of support module, carry the thing board with drive module rigid connection, just carry the thing board with the flexible hinge joint of support module.

As an improvement of the present invention, the driving module includes a Y-direction linear displacement stage and an X-direction linear displacement stage mounted on an upper surface of the Y-direction linear displacement stage, a neutral line of a movement direction of the Y-direction linear displacement stage and a neutral line of a movement direction of the X-direction linear displacement stage are arranged perpendicular to each other, the Y-direction linear displacement stage and the X-direction linear displacement stage are both in communication connection with the control module, and the stage plate is rigidly connected to an upper surface of the X-direction linear displacement stage.

As an improvement of the invention, the object carrying plate and the upper surface of the X-direction linear displacement table are connected through bolts or welded with each other.

As an improvement of the present invention, the support module includes a Y-direction linear slide rail arranged in parallel with a neutral line of the Y-direction linear displacement table in the moving direction, and an X-direction linear slide rail arranged in parallel with a neutral line of the X-direction linear displacement table in the moving direction, the number of the Y-direction linear slide rails is the same as the number of the X-direction linear slide rails, the Y-direction linear slide rails and the X-direction linear slide rails are matched with each other in a one-to-one manner, the X-direction linear slide rails are disposed on the surfaces of the Y-direction linear slide rails, and the object carrying plate is flexibly hinged to each of the X-direction linear slide rails.

As an improvement of the present invention, the sliding strokes of the Y-direction linear slide rail and the X-direction linear slide rail are the same and are both greater than the moving strokes of the Y-direction linear displacement table and the X-direction linear displacement table.

As an improvement of the invention, ball joint blocks are respectively arranged on the surface of each X-direction linear slide rail, and ball head thread pairs which are matched with the ball joint blocks in a one-to-one manner are arranged on the carrying plate.

As an improvement of the invention, the upper surface of the carrying plate is provided with an optical flat crystal.

As an improvement of the invention, the middle part of the carrying plate is provided with a through hole.

By adopting the technical scheme, the invention has the following beneficial effects:

1. the differential system is formed by arranging the two guide modules of the driving module and the supporting module, so that the motion stroke is effectively improved under the condition of ensuring the motion precision, and high precision and large stroke can be realized simultaneously.

2. Each part of the motion platform is modularized according to functions, and the motion guide element is modularized into a driving module and a supporting module; the working carrying plane of the motion platform is modularized into a carrying plate part, each module is a universal component, the number of the partial modules can be increased or decreased as required, and secondary development flexibility is good.

3. Only one rigid connection is introduced between the driving module of the motion platform and the carrying plate, and the rest are flexibly hinged, so that zero-time super-constraint design is realized, the phenomenon of blocking is not easy to occur, and the installation and adjustment process of the system is relatively simple.

Drawings

FIG. 1 is a schematic structural diagram of a two-dimensional motion platform in an embodiment;

FIG. 2 is a schematic structural diagram of a support module of a two-dimensional motion platform in an embodiment;

FIG. 3 is a schematic connection diagram of a ball-and-socket connection block and a ball head thread pair which are matched with each other in the embodiment;

FIG. 4 is a diagram of a four-component six-rail mechanical model in an embodiment;

FIG. 5 is a schematic diagram of a six-member six-rail two-hinge mechanical model in an embodiment;

fig. 6 is a schematic diagram of fig. 5 after projection of the reference plane.

Parts and components are omitted from the upper drawing, and the corresponding marks in the drawing are as follows:

10-carrying plate; 11-perforating;

12-a through hole; 13-ball head thread pair;

14-optical flat crystal; 20-a drive module;

a 21-Y direction linear displacement table; a 22-X direction linear displacement platform;

30-a support module; a 31-Y direction linear slide rail;

a 32-X direction linear slide rail; 33-ball and socket joint block.

And 40, a control module.

Detailed Description

The invention will be further described with reference to specific examples:

the two-dimensional motion platform that this embodiment provided is the two-dimensional motion platform of a high accuracy high stroke and easy assembly, and is the high-accuracy two-dimensional motion platform of modularization that easily builds, can be applied to all kinds of high accuracy measurement and system of processing, like three-coordinate measuring machine, microscope, surface profile appearance, photoetching machine and 3D printing apparatus etc..

As shown in fig. 1-3, the two-dimensional motion platform provided in this embodiment includes a horizontally disposed carrier plate 10, a driving module 20 for driving the carrier plate 10 to move, a supporting module 30 for supporting the carrier plate 10, and a control module 40 for controlling the motion of the driving module 20, wherein the control module 40 is a conventional module, and is directly available on the market, and is not important in this embodiment and will not be described in detail here.

The carrier plate 10 is horizontally disposed above the drive module 20 and the support module 30, and the drive module 20 and the support module 30 are preferably located at positions corresponding to the front half and the rear half of the carrier plate 10, respectively, or at positions corresponding to the left half and the right half of the carrier plate 10, respectively. The carrier plate 10 and the drive module 20 are rigidly connected and the carrier plate 10 and the support module 30 are flexibly hinged, the specific connection structure being described below. Preferably, the optical flat crystal 14 is placed on the upper surface of the object carrying plate 10 as a plane reference, so that the motion precision is further improved. In addition, the carrier plate 10 has a through hole 11 formed at a central position thereof, and since the carrier plate 10 has been lifted by the driving module 20 and the supporting module 30, a space therebelow is released, which can be used for mounting a processing tool of a processing system or a sensing device of a measuring machine, etc. in cooperation with the through hole 11. Specifically, the through hole 11 is a square hole, the diameter of the optical flat crystal 14 is larger than the side length of the square cross section of the square hole, and the central axis of the optical flat crystal 14 and the central axis of the square hole are coaxially arranged.

The driving module 20 comprises a Y-direction linear displacement table 21 and an X-direction linear displacement table 22 installed on the upper surface of the Y-direction linear displacement table 21, wherein the Y-direction linear displacement table 21 and the X-direction linear displacement table 22 are linear displacement tables directly available on the market, a neutral line of a motion direction of the Y-direction linear displacement table 21 and a neutral line of a motion direction of the X-direction linear displacement table 22 are arranged perpendicular to each other, and the Y-direction linear displacement table 21 and the X-direction linear displacement table 22 are both in communication connection with the control module 30, and the specific communication connection manner can be a conventional manner, such as bluetooth connection or wire connection; the objective plate 10 is rigidly connected to the upper surface of the X-direction linear displacement stage 22, and the specific rigid connection structure may be a conventional structure, such as a welded connection, a bolted connection, or a locked connection, and in this embodiment, the objective plate 10 and the upper surface of the X-direction linear displacement stage 22 are described as being connected by a bolt or welded to each other. The control module 40 can control the driving module 20 to move in the XY plane and try to feed back the motion coordinates of each displacement table, of course, the XY plane is a horizontal plane, and the X direction and the Y direction mentioned in this embodiment both refer to two mutually perpendicular directions on the XY plane.

The support module 30 includes a Y-direction linear slide rail 31 disposed parallel to a neutral line of the movement direction of the Y-direction linear displacement table 21 and an X-direction linear slide rail 32 disposed parallel to a neutral line of the movement direction of the X-direction linear displacement table 22, that is, the Y-direction linear slide rail 31 and the X-direction linear slide rail 32 are disposed perpendicular to each other, wherein there are two or more Y-direction linear slide rails 31 and X-direction linear slide rails 32, respectively, and the number of the Y-direction linear slide rails 31 is the same as that of the X-direction linear slide rails 32 and the Y-direction linear slide rails 31 and the X-direction linear slide rails 32 are matched with each other one to one. Of the Y-direction linear guide 31 and the X-direction linear guide 32 that are engaged with each other, the X-direction linear guide 32 is provided on the guide surface of the Y-direction linear guide 31, and the Y-direction linear guide 31 and the X-direction linear guide 32 are commercially available linear guides. The sliding strokes of the Y-direction linear slide rail 31 and the X-direction linear slide rail 32 are the same and are both larger than the moving strokes of the Y-direction linear displacement table 21 and the X-direction linear displacement table 22. In this way, the support module 30 is free to move in the XY plane with a greater range of motion than the drive module 20.

The object carrying plate 10 is flexibly hinged on each X-direction linear sliding rail 32, specifically, a ball joint block 33 is respectively arranged on the rail surface of each X-direction linear sliding rail 32, and a ball is arranged on the ball joint block 33. Each ball joint block 33 is fixed to the corresponding X-direction linear slide rail 32 by a bolt connection structure, and the horizontal plane of each ball joint block 33 is lower than the upper surface of the driving module 20. In addition, the object carrying plate 10 is provided with through holes 12 at positions corresponding to the ball joint blocks 33, and ball screw pairs 13 arranged by inserting balls into the corresponding ball sockets are provided in the through holes 12, that is, the object carrying plate 10 is provided with the ball screw pairs 13 which are matched with the ball joint blocks 33 one to one. It should be noted that, before use, the ball screw pair 13 needs to be fully contacted with the corresponding ball socket by adjusting the screw thread, and at this time, a gap should be left between the lower surface of the object plate 10 and the upper surface of the support module 30.

When the device is used, the control module 40 sends a motion instruction, the control driving module 20 moves according to the instruction, the object carrying plate 10 moves along with the motion at the moment, and the supporting module 30 is driven to move through the mutually matched ball head thread pair 13 and the ball socket connecting block 33, and as the supporting module 30 does not limit the motion of the object carrying plate 10, only the supporting and stable renting are realized, and high-precision two-dimensional large-stroke motion can be realized.

The present embodiment is further explained in terms of mechanical structure.

If the flexible hinges in this embodiment are all rigidly connected, the two-dimensional motion system formed by the flexible hinges is similar to a conventional two-dimensional motion system and can be simplified into a mechanical structure as shown in fig. 4, specifically, the two-dimensional motion platform includes four components, which are respectively a carrier plate 10, a driving module 20, and two sets of combined components of a Y-direction linear slide rail 31 and an X-direction linear slide rail 32, which are mutually matched, and each component has 6 original degrees of freedom in three-dimensional space, that is, X, Y, Z three linear degrees of freedom and three angular degrees of freedom which are respectively rotated around X, Y, Z axis. In addition, the two-dimensional motion platform has six guide elements, namely a Y-direction linear displacement table 21, an X-direction linear displacement table 22, two Y-direction linear slide rails 31 and two X-direction linear slide rails 32, and each guide element can be regarded as a motion pair. Since each guide element only allows linear movement in its guide direction, 5 degrees of freedom are constrained, and the system degrees of freedom are:

Dof＝m×6-n×5＝-6

in the above formula, m is the number of components, and n is the number of guide elements. The calculation result is-6, which indicates that the motion platform has high-order super-constraint, and only when the X-direction linear displacement table 22 and the two X-direction linear slide rails 32 are strictly arranged in parallel and the Y-direction linear displacement table 21 and the two Y-direction linear slide rails 31 are also strictly parallel, virtual constraint can be formed, so that the degree of freedom of the motion platform is improved, and the difficulty is very high in the actual assembly and adjustment process; moreover, when the number of supports is increased, the secondary over-constraint condition is more severe, thus causing the resulting interference of the guide elements of the motion platform, the "jamming" phenomenon, or the forced deformation of the guide elements;

in the two-dimensional motion platform provided in this embodiment, since the object carrying plate 10 has only one rigid connection with the driving module 20, and the others are flexibly hinged, and the mechanical structure of the two-dimensional motion platform is as shown in fig. 5, the two-dimensional motion platform includes six members, which are respectively an object carrying plate, a driving module, two ball screw pairs 13, and two sets of combined members of the Y-direction linear slide rail 31 and the X-direction linear slide rail 32 that are matched with each other, the two-dimensional motion platform includes six guiding elements, which are respectively a Y-direction linear displacement table 21, an X-direction linear displacement table 22, two Y-direction linear slide rails 31 and two X-direction linear slide rails 32, and in addition, there are two flexible hinges, each flexible hinge only constrains X, Y, Z three linear degrees of freedom, and then the system degree of freedom is:

Dof＝m×6-n×5-p×3＝0

in the above formula, m is the number of components, n is the number of guide elements, and p is the flexible hinge transmission. The calculation result is 0. For the two-dimensional motion platform, two degrees of freedom are required, namely, the X and Y degrees of freedom, so that the two-dimensional motion platform provided by the embodiment still has 2 times of super-constraints, and in order to release the 2 times of super-constraints.

The two-dimensional motion platform provided by this embodiment is installed and adjusted by placing the whole two-dimensional motion platform on a reference plane, for example, a horizontal marble plane, and all the guide elements only need to be parallel to the reference plane. This adjustment can be done with only one level or simple height gauge, and when all the guiding elements are parallel to the reference plane, the mechanical model can be projected to the reference plane for simplification, as shown in fig. 6, each member has 3 degrees of freedom, i.e. X, Y and one in-plane rotational degree of freedom; each guide element restrains 2 degrees of freedom and only keeps the freedom of movement of the guide direction; each flexible hinge constrains 2 degrees of freedom, leaving only in-plane rotational degrees of freedom. Substituting the number of components m as 6, the number of guide rails n as 6, and the number of hinges p as 2, the degree of freedom of the motion platform is as follows:

Dof＝m×3-n×2-p×2＝2

the degree of freedom of the motion platform is 2, the two-dimensional plane motion condition is just met, and the motion platform is a zero-order super-constrained system. In the specific installation and adjustment process, the condition that all the guides are parallel to the reference plane is only required. The adjustment of the line-plane parallelism is easy to realize, the reference plane and all the guide elements can be kept horizontal by a level gauge, and the height of the reference plane can be adjusted by a plurality of points on the guide elements by a height gauge. And each guide element can be freely placed in a plane parallel to the reference plane, and the X-direction linear displacement table 22 and the Y-direction linear displacement table 21 in the motion platform are perpendicular to each other only through rigid connection ends, so that the XY motion axis of the whole system is perpendicular.

Further, when there are more than two moving members in the driven support module 3, each time one moving member is introduced, 2 members, 2 guide rails and 1 hinge are introduced, that is, in the mechanical model shown in fig. 6, m is 2, n is 2, and p is 1. The newly added degrees of freedom of the motion platform are as follows:

Δ _DoF＝m×3-n×2-p×2＝0

this means that the introduction of new motion components in the support module 30 does not bring about a change in the degrees of freedom of the motion platform, and therefore modular motion components can be added freely.

The two-dimensional motion platform provided by the embodiment adopts a zero-order super-constrained design, simplifies the assembly requirement of the guide element, avoids the problem of 'jamming' of the traditional platform, and realizes high-precision two-dimensional motion of the object carrying plate 10 in the XY plane. The drive module 20 and the support module 30 in the platform are formed by universal guide elements, have good interchangeability and universality, and have good secondary development space. The hollow design of the object carrying plate releases the space below the motion platform, the differential design is realized by combining the optical flat crystal 14 reference, the requirement on the precision of a guide part is reduced, and the high-precision three-dimensional measurement and positioning of elements with general precision can also be realized.

The present invention is described in detail with reference to the attached drawings, but the embodiments of the present invention are not limited to the above embodiments, and those skilled in the art can make various modifications to the present invention based on the prior art, which fall within the scope of the present invention.

Claims

1. A two-dimensional motion platform is characterized by comprising a horizontally arranged object carrying plate, a driving module for driving the object carrying plate to move, a supporting module for supporting the object carrying plate and a control module for controlling the driving module to move, wherein the object carrying plate is horizontally arranged above the driving module and the supporting module, the object carrying plate is rigidly connected with the driving module, and the object carrying plate is flexibly hinged with the supporting module.

2. The two-dimensional motion platform of claim 1, wherein the driving module comprises a Y-direction linear displacement stage and an X-direction linear displacement stage mounted on an upper surface of the Y-direction linear displacement stage, a neutral line of a motion direction of the Y-direction linear displacement stage is perpendicular to a neutral line of a motion direction of the X-direction linear displacement stage, the Y-direction linear displacement stage and the X-direction linear displacement stage are both in communication connection with the control module, and the stage plate is rigidly connected to the upper surface of the X-direction linear displacement stage.

3. The two-dimensional motion platform of claim 2, wherein the object plate is connected with the upper surface of the X-direction linear displacement table through bolts or welded with each other.

4. The two-dimensional motion platform according to claim 2, wherein the support module comprises Y-directional linear slides arranged parallel to a neutral line of the motion direction of the Y-directional linear displacement table and X-directional linear slides arranged parallel to a neutral line of the motion direction of the X-directional linear displacement table, the number of the Y-directional linear slides is the same as that of the X-directional linear slides, the Y-directional linear slides and the X-directional linear slides are matched with each other in a one-to-one manner, the X-directional linear slides are disposed on the slide rail surfaces of the Y-directional linear slides, and the object carrying plate is flexibly hinged to each of the X-directional linear slides.

5. The two-dimensional motion platform of claim 4, wherein the sliding strokes of the Y-direction linear slide rail and the X-direction linear slide rail are the same and are both larger than the moving strokes of the Y-direction linear displacement stage and the X-direction linear displacement stage.

6. The two-dimensional motion platform of claim 4, wherein the surface of the slide rail of each X-direction linear slide rail is provided with a ball-and-socket joint block, and the carrier plate is provided with a ball-and-socket thread pair which is matched with each ball-and-socket joint block in a one-to-one manner.

7. The two-dimensional motion platform of any one of claims 1-6, wherein an optical flat is placed on the upper surface of the stage plate.

8. The two-dimensional motion platform of any one of claims 1-6, wherein the middle portion of the carrier plate is perforated.