CN110573306B

CN110573306B - Multi-degree-of-freedom parallel mechanism

Info

Publication number: CN110573306B
Application number: CN201880027944.4A
Authority: CN
Inventors: 周啸波; 蓝青
Original assignee: Suzhou Mailan Medical Technologies Co ltd
Current assignee: Suzhou mailan Technology Co.,Ltd.
Priority date: 2018-04-10
Filing date: 2018-11-27
Publication date: 2021-04-13
Anticipated expiration: 2038-11-27
Also published as: CN110545963B; WO2019196421A1; CN110573306A; WO2019196422A1; CN110355737A; CN110355737B; CN110545963A

Abstract

A multi-degree-of-freedom parallel mechanism comprises a bridge component (2), a main support component (3) and a secondary support component (4); the main support assembly (3) comprises at least one parallelogram mechanism; the bridge assembly (2) is rotatably connected to the main support block (30) such that the bridge assembly (2) can rotate relative to the main support block (30) about two axes that are not parallel to each other, the bridge assembly (2) is also rotatably connected to the secondary support block (40) such that the bridge assembly (2) can rotate relative to the secondary support block (40) about two axes that are not parallel to each other; the bridge assembly (2) has at least two translational degrees of freedom and two rotational degrees of freedom. The multi-degree-of-freedom parallel mechanism is high in control precision, simple in structure and high in space utilization rate.

Description

Multi-degree-of-freedom parallel mechanism

Reference to related applications

The present invention claims priority of an invention patent application entitled "translation mechanism and multiple degree of freedom guide mechanism with the translation mechanism" filed in china on 4/10/2018, entitled "translation mechanism and multiple degree of freedom guide mechanism", application No. 201810316146.5, which is incorporated herein by reference in its entirety.

Technical Field

The invention relates to the field of robots, in particular to a multi-degree-of-freedom parallel mechanism of a parallel robot.

Background

From the perspective of mechanics, robots can be divided into two categories, namely series robots and parallel robots, and compared with the series robots, the parallel robots have the advantages of high rigidity, strong bearing capacity, high precision, small inertia of end pieces and the like.

The existing parallel robot mostly adopts a completely symmetrical design, so that the whole robot is large in size and cannot better adapt to a small operation space or a plurality of robots are simultaneously arranged in a limited space.

The most common parallel robots are mostly six degrees of freedom, for example patent US3295224A discloses a parallel robot for motion simulation. However, the cost of a parallel robot with six degrees of freedom is often that the motion space of each degree of freedom is roughly divided equally, and some requirements of having a larger motion space in a specific direction cannot be met well. Therefore, the freedom degree in some directions is limited according to specific requirements, and the motion space in other directions is larger, the application of the parallel robot in the aspect is the most widely used for picking operation, and the freedom degree of three-translation-one-rotation is provided for the most, for example, patent CN105729450B discloses a four-freedom-degree parallel mechanism which can realize the freedom degree of three-translation-one-rotation of the movable platform but can not realize the rotation of the movable platform around the y axis or the x axis. For another example, patent publication WO2009053506a1 discloses a four-degree-of-freedom parallel robot, in which a plurality of non-coplanar four-bar linkages are used as a support portion, and the motions of the non-coplanar four-bar linkages are restricted with each other, so that the movable platform of the terminal cannot realize two-translation and two-rotation degrees of freedom.

However, in applications such as surgical robots or machine tools, where it is necessary to control the degrees of freedom of at least two translations and two rotations of a tool, the parallel mechanism providing three translations and one rotation is not suitable.

Disclosure of Invention

The invention aims to overcome or at least alleviate the defects of the prior art and provide a multi-degree-of-freedom parallel mechanism which can realize a relatively large motion range in a limited space and at least has two translation degrees of freedom and two rotation degrees of freedom.

According to a first aspect of the present invention, there is provided a multiple degree of freedom parallel mechanism comprising a bridge assembly, a primary support assembly and a secondary support assembly;

the main supporting assembly comprises a main supporting block, a main first moving piece, a main second moving piece, a main first rod, a main second rod, a main third rod and a main guide piece, the main first moving piece and the main second moving piece move under the guidance of the main guide piece, and two ends of the main third rod are respectively connected with the main supporting block and the main second moving piece in a rotating mode; one end of the main first rod and the main supporting block are rotatably connected to a first point, the other end of the main first rod and the main first movable part are rotatably connected to a second point, one end of the main second rod and the main supporting block are rotatably connected to a third point, the other end of the main second rod and the main first movable part are rotatably connected to a fourth point, connecting lines of the first point, the second point, the third point and the fourth point form a parallelogram, and the plane where the parallelogram is located is a main foundation plane;

the secondary support assembly comprises a secondary support block, a secondary first movable piece, a secondary second movable piece, a secondary first rod, a secondary second rod, a secondary third rod and a secondary guide piece, the secondary first movable piece and the secondary second movable piece move under the guidance of the secondary guide piece, and two ends of the secondary third rod are respectively in rotating connection with the secondary support block and the secondary second movable piece; one end of the secondary first rod is rotatably connected with the secondary supporting block to a secondary first point, the other end of the secondary first rod is rotatably connected with the secondary first movable part to a secondary second point, one end of the secondary second rod is rotatably connected with the secondary supporting block to a secondary third point, the other end of the secondary second rod is rotatably connected with the secondary first movable part to a secondary fourth point, connecting lines of the secondary first point, the secondary second point, the secondary third point and the secondary fourth point form a parallelogram, and the secondary supporting block moves in a secondary base plane;

said bridge assembly being rotatably coupled to said primary support block such that said bridge assembly is rotatable relative to said primary support block about two axes that are non-parallel to each other, said bridge assembly also being rotatably coupled to said secondary support block such that said bridge assembly is rotatable relative to said secondary support block about two axes that are non-parallel to each other;

the bridge assembly has at least two translational degrees of freedom and two rotational degrees of freedom.

According to a second aspect of the present invention, there is provided a multiple degree of freedom parallel mechanism comprising a bridge assembly, a primary support assembly and a secondary support assembly;

the secondary support assembly comprises a secondary support block, a secondary first rod, a secondary second rod and a secondary guide piece, one end of the secondary first rod is rotatably connected with the secondary support block, the other end of the secondary first rod is rotatably connected with the secondary guide piece, one end of the secondary second rod is rotatably connected with the secondary support block, the other end of the secondary second rod is rotatably connected with the secondary guide piece, and the secondary support block moves in a secondary base plane where the secondary first rod and the secondary second rod are located;

In at least one embodiment, the secondary support assembly further comprises a secondary first movable member and a secondary second movable member, the secondary first movable member and the secondary second movable member are guided to move by the secondary guide member,

one end of the secondary first rod and one end of the secondary second rod are rotatably connected with the secondary supporting block at the same point, the other end of the secondary first rod is rotatably connected with the secondary first movable piece, and the other end of the secondary second rod is rotatably connected with the secondary second movable piece.

In at least one embodiment, one end of the secondary first bar and one end of the secondary second bar are rotatably connected to the secondary support block at the same point, the other end of the secondary first bar and the other end of the secondary second bar are rotatably connected to the secondary guide at two different points,

the secondary first rod and the secondary second rod are capable of controlled elongation or contraction, respectively.

In at least one embodiment, the primary first moveable member includes a sliding member that translates guided by the primary guide and a rotating member that is rotatably connected to the sliding member relative to the sliding member, the rotational connection points of the primary first and second rods to the primary first moveable member being located at the rotating member.

In at least one embodiment, the bridge assembly includes a first stent and a second stent, the first stent and the second stent being translatably or rotatably connected to each other,

the primary support block and the first extendable member are rotatably coupled about two mutually perpendicular axes, and the secondary support block and the second extendable member are rotatably coupled about two mutually perpendicular axes, the first extendable member and the second extendable member approaching or receding from each other during movement of the primary support block and/or the secondary support block.

In at least one embodiment, the primary guide and the secondary guide are translatable synchronously or independently of each other, or

The primary guide and the secondary guide are rotatable synchronously or independently of each other.

In at least one embodiment, the primary base plane and the secondary base plane are always parallel.

In at least one embodiment, the secondary first rod includes a secondary first rod first portion and a secondary first rod second portion that are rotatable with respect to each other, the secondary second rod includes a secondary second rod first portion and a secondary second rod second portion that are rotatable with respect to each other, the secondary first rod first portion is rotatably connected to the secondary first movable member through an adapter that provides two rotation axes perpendicular to each other, the secondary first rod second portion is rotatably connected to the secondary support member, the secondary second rod first portion is rotatably connected to the secondary second movable member through an adapter that provides two rotation axes perpendicular to each other, the secondary second rod second portion is rotatably connected to the secondary support member,

the position of the secondary base plane changes with the movement of the first and/or second movable member.

In at least one embodiment, said secondary first bar and said secondary second bar are each rotatably connected to said secondary guide by means of an adapter, preferably a spherical hinge, capable of providing three degrees of freedom,

the position of the secondary base plane changes with the extension and retraction of the secondary first bar and/or the secondary second bar.

The invention constructs a multi-degree-of-freedom parallel mechanism with a structure which is not necessarily symmetrical, and the terminal of the multi-degree-of-freedom parallel mechanism can realize the freedom degree of at least two translation and two rotation. The multi-degree-of-freedom parallel mechanism is high in control precision, simple in structure and high in space utilization rate.

Drawings

Fig. 1 is a schematic view of a multiple degree of freedom parallel mechanism according to a first embodiment of the present invention.

Fig. 2 is a schematic view of the support assembly of fig. 1.

Fig. 3 is a schematic view of a variant of the bridge assembly of the multiple degree of freedom parallel mechanism according to the first embodiment of the invention.

Fig. 4 is a schematic view of a modification of the support assembly of the multiple degree of freedom parallel mechanism according to the first embodiment of the present invention.

Fig. 5 is a schematic view of a modification of the support assembly of the multiple degree of freedom parallel mechanism according to the first embodiment of the present invention.

Fig. 6 is a schematic view of a multiple degree of freedom parallel mechanism according to a second embodiment of the present invention.

FIG. 7 is a schematic view of a partial structure of the main support assembly of FIG. 6.

Fig. 8 is a side view of a multiple degree of freedom parallel mechanism according to a second embodiment of the present invention.

FIG. 9 is a schematic view of a variation of a bridge assembly of a multiple degree of freedom parallel mechanism according to a second embodiment of the present invention.

Fig. 10 is a schematic view of a multiple degree of freedom parallel mechanism according to a third embodiment of the present invention.

FIG. 11 is a schematic view of a variation of the main support assembly of the multiple degree of freedom parallel mechanism according to the third embodiment of the present invention.

Fig. 12 is a schematic view of a modification of the secondary support assembly of the multiple degree of freedom parallel mechanism according to the third embodiment of the present invention.

FIG. 13 is a schematic view of a variation of a secondary support assembly of a multiple degree of freedom parallel mechanism according to the present invention.

Fig. 14 to 16 are schematic diagrams of three implementations of a multiple degree of freedom parallel mechanism according to a fourth embodiment of the present invention.

Fig. 17 and 18 are schematic diagrams of two implementations of a multiple degree of freedom parallel mechanism according to a fifth embodiment of the present invention.

Fig. 19 to 21 are schematic diagrams of three implementations of a multiple degree of freedom parallel mechanism according to a sixth embodiment of the present invention.

Description of reference numerals:

1 supporting the assembly; 10 a support block; 11 a first lever; 12 a second lever; 13 a third lever; 14 a fourth bar; 15 a first movable member; 16 a second movable member; 17 a guide member; 171 a first guide; 172 a second guide; 1721 a first section; 1722 a second section; 18 a third movable member;

2, a bridge component; 21 a first transition piece; 22 a second adaptor; 23 a first extension; 231 a guide part; 232 extending the guide part; 24a second stent; 25 a termination;

3 a main support assembly; 30 main supporting blocks; 31 a primary first lever; 32 primary secondary rods; 33 a primary third lever; 34 a primary first movable member; 341 a rotating member; 342 a sliding member; 35 a primary second movable member; 36 main guide members; 361 a primary first guide; 362 primary second guide; 37 primary fourth bar;

4 times of supporting the assembly; 40 times of supporting blocks; 41 times a first lever; 42 times the second rod; a secondary first rod first portion 411; a secondary first rod second portion 412; the secondary second lever first portion 421; secondary second rod second portion 422; 43 times the first moving part; 44 times the second moving part; a 45-time guide; 451 times the first guide; 452 second guides;

5, a traction belt; 6, guiding a connecting piece; and 7, balancing the weight.

Detailed Description

Exemplary embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood that the detailed description is intended only to teach one skilled in the art how to practice the invention, and is not intended to be exhaustive or to limit the scope of the invention.

Unless otherwise specified, the present invention describes the positional relationship of the respective components in a three-dimensional coordinate system shown in fig. 1. It should be understood that the positional relationships defined in the present invention with respect to the x, y and z axes are relative and that the axes may be rotated in space depending on the actual application of the device.

(first embodiment)

A first embodiment of the multiple degree of freedom parallel mechanism of the present invention and its related modifications will be first described with reference to fig. 1 to 5.

Referring to fig. 1, the parallel mechanism according to the first embodiment of the present invention includes two sets of support members 1 (one of the two sets of support members 1 is also referred to as a primary support member, and the other is referred to as a secondary support member) and a bridge member 2 connecting the two sets of support members 1.

Each group of support elements 1 is moved by two moving elements (a first moving element 15 and a second moving element 16) as active elements in the xoy plane (hereinafter also referred to as the base plane) to transmit motion, so that the support block 10 at the end of the support element 1 can have two-way translational freedom in the base plane. The bridge component 2 is guided by the two movable parts, so that the bridge component 2 has two translational and two rotational degrees of freedom. The end piece 25 has a translational degree of freedom in a third direction relative to the bridge assembly 2, so that the end piece 25 can have three translational and two rotational degrees of freedom.

Next, the detailed structure and the movement of the support assembly 1 will be described with reference to fig. 2.

The support assembly 1 includes a guide 17, a first movable member 15, a second movable member 16, four links (a first rod 11, a second rod 12, a third rod 13, and a fourth rod 14), and a support block 10.

The guide 17 lies in the base plane xoy plane. The guide member 17 may be a slide rail, a slide groove, a slide rod, or other devices that provide a guide path for the movement of the first movable member 15 and the second movable member 16, and the present invention is not limited to the specific form of the guide member 17.

In the present embodiment, the guide 17 includes a first guide 171 and a second guide 172, both the first guide 171 and the second guide 172 are linear sliding grooves, and the first guide 171 and the second guide 172 are not parallel. The first movable member 15 reciprocates along the first guide member 171, and the second movable member 16 reciprocates along the second guide member 172.

One end of the first rod 11 and one end of the second rod 12 are respectively and rotatably connected (relatively rotatably connected) with the first movable member 15, and the other end of the first rod 11 and the other end of the second rod 12 are respectively and rotatably connected with the support block 10; one end of the third rod 13 and one end of the fourth rod 14 are respectively and rotatably connected with the second movable member 16, and the other end of the third rod 13 and the other end of the fourth rod 14 are respectively and rotatably connected with the supporting block 10. The first rod 11, the second rod 12, the first movable member 15 and the support block 10 form a planar four-bar mechanism, and four rotation connection points of the planar four-bar mechanism form four vertexes of a parallelogram. The third rod 13, the fourth rod 14, the second movable member 16 and the support block 10 form a planar four-bar mechanism, and four rotation connection points of the planar four-bar mechanism form four end points of a parallelogram, and the planar four-bar mechanism is a parallelogram mechanism/is a parallelogram.

The planar four-bar mechanism is in a parallelogram shape and has the following functions: in the process of the planar four-bar mechanism moving, the posture of the support block 10 relative to the first movable member 15/the second movable member 16 is determined, that is, the support block 10 does not rotate relative to the first movable member 15/the second movable member 16, especially does not rotate around the z direction, and as long as the first movable member 15/the second movable member 16 only performs translation, the support block 10 also performs translation.

In this embodiment, the first movable member 15 and the second movable member 16 reciprocate along the first guide member 171 and the second guide member 172, respectively, independently, so that the support block 10 has two translational degrees of freedom (translational movement in the x direction and translational movement in the y direction) in the xoy plane.

In fact, it is ensured that the support block 10 has a determined attitude during translation, provided that a parallelogram mechanism is provided in the support assembly 1. Therefore, in the present embodiment, any one of the first rod 11, the second rod 12, the third rod 13, and the fourth rod 14 may be omitted.

It should be noted that the first guide member 171 and the second guide member 172 are not arranged in parallel, which improves space utilization. As shown in fig. 2, when the guides 17 are disposed on the base table, for the same size of base table, the first guides 171 and the second guides 172 are formed at an angle so that the movable range of the support block 10 is larger, and a plurality of sets of the guides 17 may be disposed in an array form (e.g., a centrosymmetric array form) in the base plane where the guides 17 are located to construct a plurality of sets of the support members 1, thereby improving space utilization.

It should be understood that the first guide member 171 and the second guide member 172 may not communicate with each other or may penetrate each other, and when the first guide member 171 and the second guide member 172 penetrate each other, it is preferable that the first guide member 171 and the second guide member 172 may be integrally formed curved (e.g., circular arc curved) rails.

In addition, the first guide member 171 and the second guide member 172 may be parallel to each other or even pass through a straight track, where there is no particular requirement for space utilization. The arrangement in which the first guide member 171 and the second guide member 172 are parallel to each other can be referred to, for example, the main guide member 36 in the second embodiment shown in fig. 6.

Continuing next with reference to fig. 1, the specific construction of the axle assembly 2, and how the two support blocks 10 at the ends of the axle assembly 2 position the axle assembly 2 to cause translation and rotation of the axle assembly 2, will be described.

The bridge assembly 2 includes a first adapter 21, a second adapter 22, a first extension 23, a second extension 24, and a termination 25.

The first and

second extensions

23 and 24 are telescoped with each other such that the entire extension assembly is telescoped in the telescoping direction. For example, the first stent 23 has a receiving cavity extending along its length, and the second stent 24 has a guide rod capable of extending into or out of the receiving cavity of the first stent 23. The present invention is not limited to the specific implementation manner of the first and second

extensible members

23 and 24 being sleeved with each other to achieve extension or retraction.

The ends of the first and

second extensions

23, 24 remote from each other are pivotally connected to the second and

first adapters

22, 21, respectively. The first adapter 21 and the second adapter 22 are also rotatably connected to the two support blocks 10, respectively. The first adapter 21 is perpendicular to the rotation axis of the support block 10 and the first adapter 21 is perpendicular to the rotation axis of the second stretcher 24, and the second adapter 22 is perpendicular to the rotation axis of the support block 10 and the second adapter 22 is perpendicular to the rotation axis of the first stretcher 23. The axle assembly 2 has a degree of freedom of rotation in the x-direction and a degree of freedom of rotation in the y-direction via the two axes of rotation provided by the first adapter part 21 and the second adapter part 22, respectively. In addition to the freedom of the bridge assembly 2 to follow the translation of the support block 10, the bridge assembly 2 also has the freedom of translation in the x-direction and the freedom of translation in the y-direction.

In the above, by controlling the movement of the first movable member 15 and/or the second movable member 16 of the two sets of support members, at least one of the two support blocks 10 is moved in the base plane, so that the stretching member formed by the first stretching member 23 and the second stretching member 24 is translated in the x direction and/or translated in the y direction and/or rotated around the x direction and/or rotated around the y direction, and the stretching member is adaptively stretched or retracted in the process to change the length of the stretching member.

Further, in order to provide the parallel mechanism with a degree of freedom of translation in the z direction, the first extending member 23 has a guide portion 231 extending along the length direction thereof, and the terminal member 25 can reciprocate along the guide portion 231 to provide the parallel mechanism with a degree of freedom of translation in the z direction. The terminal member 25 is for example a robot or a drill or other performing terminal. It will be appreciated that the termination may have more degrees of freedom when the termination 25 includes other movement mechanisms, for example, when the termination 25 has a shaft, the output of the termination 25 may also have a degree of freedom to rotate about the z-direction.

It should be understood that the guide portion 231 for guiding the terminal member 25 to reciprocate may be provided to the second extending member 24. Furthermore, instead of adding an additional end piece to the stretching assembly for translation relative to the stretching assembly, it is also possible to transfer the degree of freedom of the parallel mechanism in translation in the z direction to another part, for example, to provide the base on which the guide 17 is mounted with the degree of freedom in translation in the z direction, or to provide the guide 17 with the degree of freedom in translation in the z direction (for example, refer to the second embodiment below).

Next, an implementation of a modification of the stretching assembly composed of the first stretching member 23 and the second stretching member 24 will be described with reference to fig. 3.

In this implementation, the first and

second extensions

23, 24 are rotationally coupled such that during rotation of the extensions, the first and

second extensions

23, 24 do not move translationally toward or away from each other, but move rotationally relative to each other toward or away from each other and change the attitude of the extension assembly.

Next, an implementation of a variation of the support assembly 1 is described with reference to fig. 4.

In this implementation, the links of the two sets of parallelogram mechanisms of four links have intersecting overlapping portions in the xoy plane. In other words, the four links and the four rotational axes of the support block 10 are arranged in a more compact manner in the y direction, thereby enabling the size of the support block 10 in the y direction to be further reduced.

Next, an implementation of yet another variation of the support assembly 1 is described with reference to fig. 5.

In this embodiment, the support element 1 has only one parallelogram mechanism, namely the parallelogram mechanism formed by the first lever 11, the second lever 12, the support block 10 and the first movable element 15. Wherein the first movable member 15 reciprocates along the first guide member 171.

One ends of the third and

fourth bars

13 and 14 are rotatably coupled to the same point as the supporting block 10. The other end of the third rod 13 is rotatably connected to a second movable member 16, and the other end of the fourth rod 14 is rotatably connected to a third movable member 18. The second movable member 16 and the third movable member 18 reciprocate along the second guide member 172.

Preferably, the second guide 172 is divided into two rectilinear guide sections (a first section 1721 and a second section 1722), the second movable member 16 reciprocates along the first section 1721, and the third movable member 18 reciprocates along the second section 1722. The first section 1721 and the second section 1722 form an included angle, which improves space utilization, so that the supporting block 10 has a larger moving range under the same base size. However, the arrangement of the second guide 172 is not essential, and the first section 1721 and the second section 1722 may be curved guide areas; first section 1721 and second section 1722 may also be formed as a straight guide area through each other; the second guide member 172 may also be devoid of two guide sections such that both the second movable member 16 and the third movable member 18 can reciprocate throughout the guide sections of the second guide member 172.

Preferably, the translation of the support block 10 is achieved by means of the second and third

movable members

16, 18, while the first movable member 15 is a driven member, which functions to ensure that the support block 10 does not rotate. The support block 10 is able to translate in the base plane by driving the second 16 and third 18 moveable members, respectively.

It should be understood that the first movable member 15 may also be used as the active member to achieve translation of the support block 10 in the base plane by driving one of the second and third

movable members

16, 18 and the first movable member 15, in which case the other of the second and third

movable members

16, 18 may be omitted.

It should be understood that, although fig. 5 shows the first guide 171 and the second guide 172 as being spaced apart in the z direction, this is not necessary, and the present implementation does not limit the positional relationship of the first guide 171 and the second guide 172.

In the above, the various implementations of the support assembly 1 and the various implementations of the bridge assembly 2 may be combined as desired to constitute the parallel mechanism according to the first embodiment of the present invention.

(second embodiment)

Next, a second embodiment of the present invention will be described with reference to fig. 6 to 9. In a second embodiment, the guide has a translational degree of freedom in the z direction; in addition, the support assemblies are further simplified in that the bridge assembly 2 is only limited in rotation about the z-direction at one end, i.e. only one of the two sets of support assemblies in rotational connection with the bridge assembly has a parallelogram mechanism.

The support assemblies with the parallelogram mechanisms are referred to as primary support assemblies and the other group as secondary support assemblies.

The primary support assembly 3 includes a primary guide 36, two primary moving members (a primary first moving member 34 and a primary second moving member 35) that reciprocate along the primary guide 36, a primary support block 30, and three primary links (a primary first lever 31, a primary second lever 32, and a primary third lever 33) connecting the primary support block 30 and the two primary moving members.

Specifically, the main guide member 36 includes two main first guide members 361 and a main second guide member 362 extending in parallel and located in a base plane (xoy plane), the main first movable member 34 reciprocates along the main first guide members 361, and the main second movable member 35 reciprocates along the main second guide member 362. The main first lever 31 and the main second lever 32 are pivotally connected at both ends to the main first movable member 34 and the main support block 30, respectively, so that the main first lever 31, the main second lever 32, the main first movable member 34 and the main support block 30 constitute a parallelogram mechanism (refer to fig. 7). The main support block 30 is also pivotally connected to a primary third bar 33, and the other end of the primary third bar 33 is pivotally connected to a primary second movable member 35.

The position of the main support block 30 in the base plane can be adjusted by controlling the position of the main first movable member 34 and the main second movable member 35 on the main guide member 36; meanwhile, since the main support block 30 is a part of the parallelogram mechanism, it does not rotate about the z direction.

The secondary support member 4 includes a secondary guide 45, two secondary moving members (a secondary first moving member 43 and a secondary second moving member 44) reciprocating along the secondary guide 45, a secondary support block 40, and two secondary links (a secondary first lever 41 and a secondary second lever 42) connecting the secondary support block 40 and the two secondary moving members.

Specifically, the secondary guide member 45 includes two secondary first guide members 451 and secondary second guide members 452 extending in parallel and located in the base plane, the secondary first movable member 43 reciprocates along the secondary first guide members 451, and the secondary second movable member 44 reciprocates along the secondary second guide members 452. Two ends of the secondary first rod 41 are respectively and rotatably connected with the secondary first movable element 43 and the secondary support block 40, two ends of the secondary second rod 42 are respectively and rotatably connected with the secondary second movable element 44 and the secondary support block 40, and the rotary connection points of the secondary first rod 41 and the secondary second rod 42 with the secondary support block 40 are the same point.

The position of the secondary support block 40 in the base plane can be adjusted by controlling the positions of the secondary first movable member 43 and the secondary second movable member 44 on the secondary guide member 45; also, since the primary and secondary support blocks 30, 40 are both attached to the axle assembly 2, and the axle assembly 2 is limited in rotational freedom about the z-direction by the primary support block 30, the secondary support block 40 is also adaptively limited in rotation about the z-direction.

It should be understood that, as described in the first embodiment, the primary first guide 361 and the primary second guide 362 may have other positional relationships in the base plane, and the secondary first guide 451 and the secondary second guide 452 may have other positional relationships in the base plane, which is not limited by the present invention. For example, fig. 13 shows an arrangement in which the secondary first guide 451 and the secondary second guide 452 are curved tracks.

The bridge assembly 2 includes a first extension 23 and a second extension 24. The first stent 23 has a stent guide 232, and the stent guide 232 is capable of cooperating with the second stent 24 to reciprocate the second stent 24 along the stent guide 232. The extension guide 232 may be in the form of a guide rail, a guide groove, a guide bar, etc., and the present invention is not limited thereto.

The first extension piece 23 is rotatably connected to the main support block 30, and the first extension piece 23 and the main support block 30 can rotate around two vertical rotation axes; the second stretcher 24 is pivotally connected to the secondary support block 40, and the second stretcher 24 and the secondary support block 40 are capable of pivoting about two perpendicular axes of rotation with respect to each other. The axle assembly 2 can have rotational freedom about the y-direction and rotational freedom about the x-direction as the primary and/or secondary support blocks 30, 40 change position.

It should be understood that the pivotal connection between the first and

second extensions

23 and 30 and the secondary support block 40 may use a universal hinge having two rotational axes perpendicular to each other, such as a hooke hinge.

The primary guide 36 and the secondary guide 45 themselves have a translational degree of freedom in the z direction. For example, the main guide 36 and the sub guide 45 can reciprocate along a guide mechanism extending in the z direction provided to the base platform. Preferably, the primary guide 36 and the secondary guide 45 are connected together by the guide link 6 to move in unison in the z direction; this is not essential, however, and the primary guide 36 and the secondary guide 45 may also be controlled independently to move in the z-direction, depending on the different control modes.

Preferably, the primary guide 36 and the secondary guide 45 are connected to the counterweight 7 by means of a traction belt 5. In particular, the traction belt 5 passes around the pulley arrangement with the primary/

secondary guides

36, 45 and the counterweight 7 on either side of the pulley in the radial direction, the counterweight 7 acting to balance the axle assembly 2, the primary support assembly 3 and the secondary support assembly 4 in the z-direction.

Referring to fig. 9, in this embodiment, the first and

second extensions

23 and 24 of the bridge assembly 2 may also be rotationally coupled, and when rotationally coupled, they may move closer to or farther from each other, not in a translational manner, but in a rotational manner.

(third embodiment)

Next, a third embodiment of the present invention will be described with reference to fig. 10 to 12. The third embodiment is a modification of the second embodiment in which the parallel mechanism has two sets of secondary support assemblies 4 and one set of modified primary support assemblies 3. The primary and

secondary guides

36, 45 may be independently translatable in the z-direction, such that the position of the primary and secondary support blocks 30, 40 in the z-direction may be varied; this not only allows the axle assembly 2 to have the freedom to translate in the z-direction, but also eliminates the need to provide the axle assembly 2 with extensions to extend or retract, since the distance between the primary and secondary support blocks 30, 40 in the z-direction can be varied, due to the variation in the distance between the

blocks

30, 40.

The arrangement of the secondary support member 4 in this embodiment is similar to that in the second embodiment. The manner in which the main support assembly 3 is arranged is described below with reference to fig. 10.

The main support assembly 3 comprises a main guide 36 and a parallelogram mechanism. The parallelogram mechanism includes a main support block 30, a main first movable element 34 (for convenience of description, the nomenclature of the second embodiment is used, and in fact, the main second movable element is not present in this embodiment), and two links (a main first lever 31 and a main second lever 32) rotatably connected at both ends to the main support block 30 and the main first movable element 34, respectively. The primary first moveable member 34 is capable of reciprocating along a guide slot on the primary guide member 36.

During actual driving, the primary first moving member 34 generally acts as a driven member rather than a driving member. The main support block 30 is rotatably coupled to the first extendable member 23 (which are rotatable about two mutually perpendicular axes of rotation), and the main support assembly 3 functions to limit uncontrolled rotation of the first extendable member 23 about the z-direction during movement.

The two sets of secondary support assemblies 4 control the translation of the first extension 23 of the bridge assembly in two directions in the base plane as well as the rotation about the x-direction and the rotation about the y-direction. In particular, the secondary support blocks 40 of the two sets of secondary support elements 4 are rotatably connected to the axle element 2 (the secondary support blocks 40 and the axle element 2 are rotatable about two mutually perpendicular axes of rotation with respect to each other).

When the secondary first and second moving

members

43 and 44 of the two sets of secondary support members 4 are driven respectively, the two secondary support blocks 40 undergo translation in the base plane (the secondary support blocks 40 are constrained by the bridge member 2 from rotation in the z-direction).

In the above, the bridge assembly 2 is guided by the two sub-support blocks 40 and controlled in posture by the main support block 30, so that the bridge assembly 2 has two translational and two rotational degrees of freedom.

It should be understood that primary guide 36 and secondary guide 45 may also be configured to be stationary, in which case bridge assembly 2 would need to be configured to include extensions that enable it to be extended or retracted.

With reference to fig. 11, a variant realisation of the main supporting assembly 3 is next described.

A variation of this implementation is that it provides another implementation of the movement of the primary first moveable member 34 relative to the primary guide member 36. In this embodiment, a main third rod 33 and a main fourth rod 37 are rotatably connected between the main first movable element 34 and the main guide element 36, and the main first movable element 34, the main guide element 36, the main third rod 33 and the main fourth rod 37 form a parallelogram mechanism. The parallelogram mechanism enables the primary first movable member 34 to move toward or away from the primary guide member 36 in a manner that does not rotate about the z-direction; the first parallelogram linkage comprising the primary first bar 31 and the primary second bar 32 is coupled in series with the second parallelogram linkage comprising the primary third bar 33 and the primary fourth bar 37, eventually bringing the primary support block 30 closer to or further from the primary guide 36 in a manner that does not rotate about the z-direction.

Referring to fig. 12, the links and the movable members of the two sets of secondary support members 4 can be replaced by telescopic rods, while the main support member 3 ensures that the bridge assembly 2 does not rotate in the z-direction.

In this variant implementation of the secondary support assembly 4, the secondary first rod 41 and the secondary second rod 42 are independently telescopic to vary in length. One ends of the sub first bar 41 and the sub second bar 42 are rotatably coupled to the same point on the sub supporting block 40, and the other ends of the sub first bar 41 and the sub second bar 42 are rotatably coupled to the sub guide 45, respectively. As the length of the secondary first bar 41 and/or the secondary second bar 42 changes, the secondary support block 40 translates in the base plane.

(fourth embodiment)

Next, a fourth embodiment of the present invention will be described with reference to fig. 14 to 16. The fourth embodiment is a modification of the second and third embodiments. In this embodiment, the parallelogram mechanism adds one degree of rotational freedom, and thus the axle assembly 2.

Referring to fig. 14, the primary first mover 34 includes a rotating member 341 and a sliding member 342, the rotating member 341 being rotatably mounted to the sliding member 342 about the z-axis with respect to the sliding member 342, and the sliding member 342 being reciprocally movable along the primary first guide 361. The main first rod 31 and the main second rod 32 of the main support assembly 3 are rotatably connected to the rotating member 341, and the main first rod 31, the main second rod 32, the main support block 30 and the rotating member 341 constitute a parallelogram mechanism. The rotation member 341 is controlled to rotate, the rotation of the rotation member 341 will drive the main support block 30 to rotate in phase, and the rotation of the main support block 30 around the z direction drives the rotation of the bridge assembly 2 located by the main support block 30 around the z direction; thus, by controlling the rotation of the rotating member 341, the rotation of the bridge assembly 2 about the z direction can be controlled.

Fig. 15 and 16 are modifications of the solutions shown in fig. 10 and 11, respectively, of the third embodiment described above, in which fig. 15 the rotating member 341 is rotatable about the z direction with respect to the sliding member 342, and in fig. 16 the rotating member 341 is rotatable about the z direction with respect to the main guide 36. In the solutions shown in fig. 15 and 16, by controlling the sliding of the secondary first movable member 43 and the secondary second movable member 44 of the two sets of secondary support members 4 and the movement of the secondary guide member 45, the translation of the bridge assembly 2 in the x direction, the translation in the y direction, the rotation around the x axis, and the rotation around the y axis can be realized, and by controlling the rotation of the rotating member 341, the rotation around the z direction of the bridge assembly 2 can be realized.

(fifth embodiment)

Next, a fifth embodiment of the present invention will be described with reference to fig. 17 to 18. The fifth embodiment is a modification of the second and third embodiments. In this embodiment, the adjustment of the attitude of the axle assembly 2 with the change of the positions of the primary and secondary support blocks 30, 40 is achieved not by the mutual extension of the parts of the axle assembly 2, nor by the translational movement of the primary and

secondary guides

36, 45 in the z-direction, but by the rotation of the primary and

secondary guides

36, 45.

Specifically, referring to fig. 17, the primary guide 36 and the secondary guide 45 are rotatable about the x direction. In this case, the primary and secondary support blocks 30, 40 are no longer constrained to translate in the base plane (xoy plane), but respectively in a primary reference plane defined by the primary first moving member 34, the primary second moving member 35 and the primary support block 30, and a secondary reference plane defined by the secondary first moving member 43, the secondary second moving member 44 and the secondary support block 40.

By varying the angle between the primary and secondary reference planes, the distance and/or position between the primary and secondary support blocks 30, 40 can be varied. The rotation angles of the main guide member 36 and the secondary guide member 45 around the x direction are controlled according to a preset control mode, and the two-translation and two-rotation freedom degree of the bridge assembly 2 can be realized by matching the positions of the main first movable member 34, the main second movable member 35, the secondary first movable member 43 and the secondary second movable member 44 on the main guide member 36 and the secondary guide member 45.

Further, the rotation of the main guide 36 and the sub guide 45 is not limited to the rotation about the x direction. For example, referring to fig. 18, the primary guide 36 and the secondary guide 45 may also be rotated in the y direction according to a preset control manner.

The present embodiment does not limit the rotational axes of the main guide 36 and the sub guide 45, and the respective rotational axes of the main guide 36 and the sub guide 45 do not have to be parallel to each other.

It should be understood that the manner of changing the positional relationship between the primary and secondary support blocks 30, 40 by rotating the primary and/or

secondary guides

36, 45 may also be applied to a mechanism having three sets of support assemblies, such as in the third embodiment above.

(sixth embodiment)

Next, a sixth embodiment of the present invention will be described with reference to fig. 19 to 21. The sixth embodiment is a modification of the second and third embodiments.

This embodiment provides yet another means for moving the primary and secondary support blocks 30, 40 in non-parallel planes, thereby adjusting the distance between the primary and secondary support blocks 30, 40 to accommodate bridge assemblies 2 that do not require extended structure.

In particular, with reference to fig. 19, the secondary first lever 41 is connected in rotation to the secondary first mobile 43 by means of an adapter and the secondary second lever 42 is connected in rotation to the secondary second mobile 44 by means of an adapter, the two adapters each providing two rotation axes perpendicular to each other. The sub first lever 41 includes a sub first lever first portion 411 and a sub first lever second portion 412 that are rotatable relative to each other, and the sub second lever 42 includes a sub second lever first portion 421 and a sub second lever second portion 422 that are rotatable relative to each other. The two adapters are connected to the secondary first lever first portion 411 and the secondary second lever first portion 421, respectively, so that the secondary first lever second portion 412 has three rotational degrees of freedom with respect to the secondary first movable member 43, and the secondary second lever second portion 422 has three rotational degrees of freedom with respect to the secondary second movable member 44. During rotation of the secondary first lever 41 and the secondary second lever 42, the plane defined by the secondary first movable element 43, the secondary second movable element 44, and the secondary support block 40 is not parallel to the base plane. In this arrangement, two translational and two rotational degrees of freedom of the axle assembly 2 can be achieved by controlling the positions of the primary first movable member 34 and the primary second movable member 35 on the primary guide member 36, and the positions of the secondary first movable member 43 and the secondary second movable member 44 on the secondary guide member 45.

Referring to fig. 20, the adaptor providing two perpendicular axes of rotation can be further replaced by a universal ball hinge 8. One rotation end of the spherical hinge 8 is fixed to the sub guide 45, and the other rotation end is fixed to the sub first rod 41/the sub second rod 42, and the sub first rod 41 and the sub second rod 42 are links that can change the length, that is, can be extended and contracted. In this solution, by controlling the positions of the primary first movable member 34 and the primary second movable member 35 on the primary guide member 36 and controlling the telescopic lengths of the secondary first rod 41 and the secondary second rod 42, the freedom degree of two translation and two rotation of the bridge assembly 2 can be realized.

Further, with reference to fig. 21, the parallel mechanism has three sets of support assemblies, and wherein two sets of secondary support assemblies 4 each use a link (secondary first rod 41 and secondary second rod 42) of variable length and a gimbaled ball hinge 8 to pivotally connect the link to the secondary guide 45. In this scheme, the degree of freedom of two-translation and two-rotation of the bridge component 2 can be realized by controlling the telescopic lengths of the secondary first rods 41 and the secondary second rods 42 of the two sets of secondary support components 4.

In summary, the parallel mechanism according to the present invention has at least two sets of support assemblies (support assembly 1 or main support assembly 3 plus secondary support assembly 4) such that the bridge assembly 2 rotationally connected to the support assemblies has at least two translational and two rotational degrees of freedom; at least one set of support assemblies is a main support assembly having at least one set of parallelogram mechanisms such that rotation of the bridge assembly 2 about the z-direction is controllably limited. On the basis of satisfying these conditions, the specific implementation of the bridge assembly 2 and the specific implementation of the support assembly may be combined by selecting appropriate components from among the six main embodiments and the modified implementations of the six embodiments provided by the present invention.

When all the support assembly guides (guide 17/primary guide 36/secondary guide 45) are fixed, the bridge assembly 2 has two translational and two rotational degrees of freedom. The bridge assembly 2 adds one degree of translational freedom in the z-direction as the guides of all the support assemblies translate together in the z-direction. In both cases, the bridge assembly 2 needs to be configured to include first and

second extensions

23, 24 that enable it to be extended or retracted, with the first and

second extensions

23, 24 being extended in a manner that moves toward or away from each other, or rotates relative to each other.

The bridge assembly 2 need not be configured to include extensions that enable it to be extended or retracted, as the guides of at least one support assembly can be independently translated or rotated relative to the guides of the other support assemblies.

Alternatively, the bridge assembly 2 need not be configured to include extensions that enable it to be extended or retracted by having the secondary first and

second rods

41, 42 of the secondary support assembly 4 pivotally connected to the secondary first and second

moveable members

43, 44, respectively, via universal hinges.

The invention has at least one of the following advantages:

(i) the invention realizes the freedom degree of at least two translations and two rotations of the bridge component 2 connected with the translation components by at least two groups of support components for realizing the translation function, and the parallel mechanism has simple structure, does not need to be symmetrical and has strong space adaptability.

(ii) The support assembly and the bridge assembly of the parallel mechanism have various alternative implementation structures, particularly the arrangement of the guide pieces is flexible and changeable, and the parallel mechanism can adapt to different installation environments.

(iii) The rotating connection mode of each rotating connecting piece of the parallel mechanism is simple, a spherical hinge is not needed, and the reliability is high.

Of course, the present invention is not limited to the above-described embodiments, and those skilled in the art can make various modifications to the above-described embodiments of the present invention without departing from the scope of the present invention under the teaching of the present invention.

For example,

(i) the parallel mechanism according to the invention is preferably used as part of a surgical robot, in which application the z-direction preferably represents the vertical direction and a surgical instrument may be added to the first or

second extensions

23, 24 of the bridge assembly 2; however, the invention is not limited thereto and the parallel mechanism according to the invention may also provide guidance for other instruments.

(ii) Although the adapters for coupling the axle assembly 2 to the support assembly 1/main support assembly 3/secondary support assembly 4 in the various embodiments of the present invention each have two axes of rotation that are perpendicular to each other, it should be understood that the two axes of rotation provided by the above adapters may not be perpendicular, as long as the adapters provide two axes of rotation that are not parallel to each other to enable the axle assembly to have two degrees of rotational freedom relative to the support assembly 1/main support assembly 3/secondary support assembly 4.

Claims

1. A multi-degree-of-freedom parallel mechanism comprises a bridge component, a main support component and a secondary support component;

the bridge assembly has at least two translational degrees of freedom and at least two rotational degrees of freedom.

2. A multi-degree-of-freedom parallel mechanism comprises a bridge component, a main support component and a secondary support component;

3. The multiple degree of freedom parallel mechanism of claim 2, wherein the secondary support member further includes a secondary first movable member and a secondary second movable member that are movable guided by the secondary guide member,

4. The multiple degree of freedom parallel mechanism of claim 2, wherein one end of the secondary first bar and one end of the secondary second bar are rotatably connected to the secondary support block at the same point, the other end of the secondary first bar and the other end of the secondary second bar are rotatably connected to the secondary guide at two different points,

5. The multiple degree of freedom parallel mechanism of any one of claims 1 to 4, wherein the primary first movable member comprises a sliding member that translates guided by the primary guide and a rotating member that is rotatably connected to the sliding member relative to the sliding member, the rotational connection points of the primary first and second levers to the primary first movable member being located at the rotating member.

6. The multiple degree of freedom parallel mechanism of any one of claims 1-4, wherein the bridge assembly comprises a first stent and a second stent, the first stent and the second stent being translatably or rotatably connected to each other,

7. The multiple degree of freedom parallel mechanism according to any one of claims 1 to 4,

the primary and secondary guides being translatable synchronously or independently of each other, or

8. The multiple degree of freedom parallel mechanism of any one of claims 1 to 4, wherein the primary base plane and the secondary base plane are always parallel.

9. The multiple degree of freedom parallel mechanism according to claim 3, wherein the secondary first lever includes a secondary first lever first portion and a secondary first lever second portion that are rotatable with respect to each other, the secondary second lever includes a secondary second lever first portion and a secondary second lever second portion that are rotatable with respect to each other, the secondary first lever first portion is rotatably connected to the secondary first movable member through an adapter that provides two rotation axes perpendicular to each other, the secondary first lever second portion is rotatably connected to the secondary support member, the secondary second lever first portion is rotatably connected to the secondary second movable member through an adapter that provides two rotation axes perpendicular to each other, the secondary second lever second portion is rotatably connected to the secondary support member,

10. The multiple degree of freedom parallel mechanism of claim 4, wherein the secondary first bar and the secondary second bar are each rotationally coupled to the secondary guide via an adapter that provides three degrees of freedom,

11. The multiple degree of freedom parallel mechanism of claim 10, wherein the adaptor is a ball hinge.