CN115284327A

CN115284327A - Multi-degree-of-freedom wrist joint, manipulator and robot

Info

Publication number: CN115284327A
Application number: CN202211024623.3A
Authority: CN
Inventors: 姜峣; 丹尼; 田向宇; 李铁民
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2022-08-25
Filing date: 2022-08-25
Publication date: 2022-11-04
Anticipated expiration: 2042-08-25
Also published as: CN115284327B

Abstract

A multi-degree-of-freedom wrist joint, a manipulator and a robot. The multi-degree-of-freedom wrist joint comprises: the central piece is provided with two first mounting shafts and two second mounting shafts, the two first mounting shafts are respectively provided with a first pulley assembly, the two second mounting shafts are respectively provided with a second pulley assembly, and the two axial ends of the central piece are respectively provided with a third pulley assembly; the two guide rail seats are respectively provided with a first arc-shaped rail and a second arc-shaped rail; the two first arc-shaped guide rails are respectively arranged on the two first arc-shaped rails, two ends of each first arc-shaped guide rail are respectively hinged to the two first mounting shafts, and the two first pulley assemblies are respectively and fixedly connected to the end parts of the two first arc-shaped guide rails; and the two second arc-shaped guide rails are respectively arranged on the two second arc-shaped tracks, two ends of each second arc-shaped guide rail are respectively hinged to the two second mounting shafts, and the two second pulley assemblies are respectively and fixedly connected to the end parts of the two second arc-shaped guide rails. The wrist joint is driven by a rope, and has low end inertia, high flexibility and a response speed block.

Description

Multi-degree-of-freedom wrist joint, manipulator and robot

Technical Field

The present document relates to the technical field of artificial intelligence, in particular to a multi-degree-of-freedom wrist joint, a manipulator and a robot.

Background

In order to perform various complex tasks, the artificial limb or the bionic mechanical arm needs to be provided with a multi-degree-of-freedom wrist joint. When the object is grabbed, the wrist joint can flexibly adjust the posture angle of the wrist joint according to actual requirements.

The wrist joint needs to move in three degrees of freedom to mimic the human wrist. However, adding a wrist joint with three degrees of freedom to the wrist of the robot arm often causes great difficulty in design, and has the problems of limited movement range of the wrist joint, very bulky volume and the like, and usually, the positions of joint axes with respective degrees of freedom need to be compromised, which also causes most wrist joints to be capable of realizing two-degree-of-freedom motion only in a very limited range, and the two-degree-of-freedom wrist joint has the problems of complex structure and incapability of better completing tasks required to be executed by the wrist joint.

In addition, the wrist joint needs to be provided with a driving element on each joint shaft, so that the weight of the wrist joint and the complexity of a transmission structure are increased rapidly, and even if the wrist joint moves under a small load, the wrist joint needs large driving capability due to large weight, so that high torque load and high movement speed are realized, and small volume, weight and inertia are kept.

Disclosure of Invention

In order to solve at least one of the above technical problems, the present application provides a multi-degree-of-freedom wrist joint having a simpler structure.

The application also provides a manipulator and a robot.

The multi-degree-of-freedom wrist joint provided by the embodiment of the invention comprises: the central piece is alternately provided with two first mounting shafts and two second mounting shafts at intervals along the circumferential direction, the two first mounting shafts are rotatably sleeved with first pulley assemblies, the two second mounting shafts are rotatably sleeved with second pulley assemblies, and both axial ends of the central piece are rotatably provided with third pulley assemblies; the central piece is positioned between the two guide rail seats, and a first arc-shaped rail and a second arc-shaped rail which are intersected are arranged on each guide rail seat; the two first arc-shaped guide rails are respectively and movably arranged on the two first arc-shaped rails, two ends of each first arc-shaped guide rail are respectively hinged to the two first mounting shafts, and the two first pulley assemblies are respectively and fixedly connected to the end parts of the two first arc-shaped guide rails; and the two second arc-shaped guide rails are movably arranged on the two second arc-shaped tracks respectively, two ends of each second arc-shaped guide rail are hinged to the two second mounting shafts respectively, and the two second pulley assemblies are fixedly connected to the end parts of the two second arc-shaped guide rails respectively.

In some exemplary embodiments, each of the guide rail seats is alternately provided with two fourth pulley assemblies and two fifth pulley assemblies at intervals along the circumferential direction, the four fourth pulley assemblies are located on the outer sides of the two first arc-shaped guide rails in a pairwise correspondence, and the four fifth pulley assemblies are located on the outer sides of the two second arc-shaped guide rails in a pairwise correspondence.

In some exemplary embodiments, the ends of both first mounting shafts are provided with a first threading structure and the ends of both second mounting shafts are provided with a second threading structure.

In some exemplary embodiments, the multiple degree of freedom wrist joint further comprises: two first mounting brackets are positioned at the outer sides of the two first arc-shaped guide rails and are respectively and fixedly connected to the end parts of the two first arc-shaped guide rails, and the two first threading structures are respectively positioned on the two first mounting brackets.

In some exemplary embodiments, the multi-degree of freedom wrist joint further comprises: the two second mounting frames are positioned on the outer sides of the two second arc-shaped guide rails and fixedly connected to the end portions of the two second arc-shaped guide rails respectively, and the two second threading structures are positioned on the two second mounting frames respectively.

In some exemplary embodiments, the multi-degree of freedom wrist joint further comprises: the first rope of the first rope driving mechanism is wound on the two fourth pulley assemblies positioned on one side of the two guide rail seats and the first threading structure; the second rope of the second rope driving mechanism is wound on the two fourth pulley assemblies positioned on the other sides of the two guide rail seats and the first threading structure; the first rope driving mechanism and the second rope driving mechanism are used for driving the two guide rail seats to drive the two second arc-shaped guide rails to swing oppositely or oppositely and reversely around the second mounting shaft.

In some exemplary embodiments, the multi-degree of freedom wrist joint further comprises: the third rope of the third rope driving mechanism is wound on the two fifth pulley assemblies positioned on one side of the two guide rail seats and the second threading structure; the fourth rope of the fourth rope driving mechanism is wound on the two fifth pulley assemblies positioned on the other sides of the two guide rail seats and the second threading structure; the third rope driving mechanism and the fourth rope driving mechanism are used for driving the two guide rail seats to drive the two first arc-shaped guide rails to swing oppositely or oppositely and reversely around the first mounting shaft.

In some exemplary embodiments, the multi-degree of freedom wrist joint further comprises: and the fifth rope is wound on one of the two first pulley assemblies and the two third pulley assemblies and is arranged to control the two first arc-shaped guide rails to synchronously swing oppositely or synchronously swing reversely around the first mounting shaft.

In some exemplary embodiments, the multiple degree of freedom wrist joint further comprises: and the sixth rope is wound on the other one of the two second pulley assemblies and the two third pulley assemblies and is arranged to control the two second arc-shaped guide rails to synchronously swing in opposite directions or synchronously swing in opposite directions around the second mounting shaft.

In some exemplary embodiments, the fifth rope includes a first sub-rope wound around one of the two first sheave assemblies and one of the two third sheave assemblies and a second sub-rope wound around the other of the two first sheave assemblies and one of the two third sheave assemblies.

In some exemplary embodiments, the sixth rope includes a third sub-rope wound around one of the two second sheave assemblies and the other of the two third sheave assemblies, and a fourth sub-rope wound around the other of the two second sheave assemblies and the other of the two third sheave assemblies.

In some exemplary embodiments, the first axes of the two first mounting shafts are collinear, the second axes of the two second mounting shafts are collinear, the third axes of the two third pulley assemblies are collinear, and the first axis, the second axis, and the third axis intersect perpendicularly at a point.

In some exemplary embodiments, the first arcuate rail is a semicircular arcuate rail, an axis of the first arcuate rail coinciding with the second axis; the second arc-shaped guide rail is a semi-arc-shaped guide rail, and the axis of the second arc-shaped guide rail is overlapped with the first axis.

The manipulator provided by the embodiment of the invention comprises the multi-degree-of-freedom wrist joint in any one of the embodiments.

The robot provided by the embodiment of the invention comprises the manipulator in any embodiment.

According to the multi-degree-of-freedom wrist joint provided by the embodiment of the invention, the fifth rope is wound on one of the two first pulley assemblies and the two third pulley assemblies, the control guide rail seat drives the two first arc-shaped guide rails to reversely swing around the first installation shaft, and the two first arc-shaped guide rails are controlled to synchronously and reversely swing around the first installation shaft through the matching structures of the fifth rope, one of the two third pulley assemblies and the two first pulley assemblies, so that the two first arc-shaped guide rails synchronously move, the response speed is obviously improved, namely the response speed is approximately doubled; a sixth rope is wound on the other one of the two second pulley assemblies and the two third pulley assemblies, the guide rail seat is controlled to drive the two second arc-shaped guide rails to reversely swing around the second mounting shaft, and the two second arc-shaped guide rails are controlled to synchronously and reversely swing around the second mounting shaft through the matching structures of the sixth rope, the other one of the two third pulley assemblies and the two second pulley assemblies, so that the synchronous action of the two second arc-shaped guide rails is realized, the response speed is obviously improved, namely the response speed is approximately doubled; the multi-degree-of-freedom wrist joint adopts a rope driving mode, and has the advantages of simple structure, low tail end inertia, high flexibility and high response speed.

Additional features and advantages of the application will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the application. Other advantages of the present application may be realized and attained by the instrumentalities and combinations particularly pointed out in the specification and the drawings.

Drawings

The accompanying drawings are included to provide an understanding of the present disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the examples serve to explain the principles of the disclosure and not to limit the disclosure.

FIG. 1 is a schematic perspective view of a multi-degree of freedom wrist joint according to an embodiment of the present invention;

FIG. 2 is a schematic perspective view of a multi-degree-of-freedom wrist joint according to another embodiment of the present invention;

FIG. 3 is a partial schematic view of an exploded view of the multi-degree of freedom wrist joint of FIG. 1;

FIGS. 4-6 are schematic partial structural views of the multi-degree of freedom wrist joint of FIG. 1;

fig. 7 is a partial structural view of the multi-degree of freedom wrist joint shown in fig. 2.

Wherein, the correspondence between the reference numbers and the part names in fig. 1 to 7 is:

100 center piece, 110 first mounting axle, 111 first pulley assembly, 120 second mounting axle, 121 second pulley assembly, 130 third pulley assembly, 200 guide rail seat, 210 first arcuate rail, 220 second arcuate rail, 230 fourth pulley assembly, 240 fifth pulley assembly, 310 first arcuate rail, 320 second arcuate rail, 410 first cord, 420 second cord, 430 third cord, 440 fourth cord, 510 first cord drive, 520 second cord drive, 530 third cord drive, 540 fourth cord drive, 610 first mounting bracket, 611 first threading structure, 620 second mounting bracket, 621 second threading structure, 710 first rolling bearing, 720 second rolling axle.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that all directional indicators (such as up, down, left, right, front, and back \8230;) in the embodiments of the present invention are only used to explain the relative positional relationship between the components, the motion situation, etc. in a specific posture (as shown in the attached drawings), and if the specific posture is changed, the directional indicators are changed accordingly.

In addition, the descriptions related to "first", "second", etc. in the present invention are only for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless explicitly specified otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "connected," "secured," and the like are to be construed broadly, and for example, "secured" may be a fixed connection, a removable connection, or an integral part; can be mechanically or electrically connected; "coupled" may be direct or indirect through an intermediary, and may be internal to two elements or an interaction of two elements unless otherwise specifically limited. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In addition, the technical solutions in the embodiments of the present invention may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination of technical solutions should not be considered to exist, and is not within the protection scope of the present invention.

As shown in fig. 1 to 7, the multi-degree-of-freedom wrist joint provided in the embodiment of the present invention includes: the central part 100 is alternately provided with two first mounting shafts 110 and two second mounting shafts 120 at intervals along the circumferential direction, the two first mounting shafts 110 are rotatably sleeved with first pulley assemblies 111, the two second mounting shafts 120 are rotatably sleeved with second pulley assemblies 121, and both axial ends of the central part 100 are rotatably provided with third pulley assemblies 130; the central piece 100 is positioned between the two guide rail seats 200, and each guide rail seat 200 is provided with a first arc-shaped track 210 and a second arc-shaped track 220 which are intersected; the two first arc-shaped guide rails 310 are movably arranged on the two first arc-shaped tracks 210 respectively, two ends of each first arc-shaped guide rail 310 are hinged to the two first mounting shafts 110 respectively, the two first pulley assemblies 111 are fixedly connected to the end parts of the two first arc-shaped guide rails 310 respectively, and the concave curved surfaces of the two first arc-shaped guide rails 310 face the central part 100; and two second arc-shaped guide rails 320 movably disposed on the two second arc-shaped rails 220, wherein two ends of each second arc-shaped guide rail 320 are hinged to the two second mounting shafts 120, the two second pulley assemblies 121 are fixedly connected to the ends of the two second arc-shaped guide rails 320, and the concave curved surfaces of the two second arc-shaped guide rails 320 face the center member 100.

As shown in fig. 2, 4 and 7, the multi-degree-of-freedom wrist joint is configured such that a fifth rope is wound around one of the two first pulley assemblies 111 and the two third pulley assemblies 130, the control guide rail base 200 drives the two first arc-shaped guide rails 310 to swing reversely around the first installation shaft 110, and controls the two first arc-shaped guide rails 310 to swing synchronously and reversely around the first installation shaft 110 through the matching structures of the fifth rope, the one of the two third pulley assemblies 130 and the two first pulley assemblies 111, so as to achieve synchronous motion of the two first arc-shaped guide rails 310, and the response speed thereof is significantly increased, that is, the response speed is increased by about twice; a sixth rope is wound on the other one of the two second pulley assemblies 121 and the two third pulley assemblies 130, the guide rail base 200 drives the two second arc-shaped guide rails 320 to swing reversely around the second mounting shaft 120, and the matching structures of the sixth rope, the other one of the two third pulley assemblies 130 and the two second pulley assemblies 121 control the two second arc-shaped guide rails 320 to swing synchronously and reversely around the second mounting shaft 120, so that the synchronous action of the two second arc-shaped guide rails 320 is realized, and the response speed is obviously improved, namely the response speed is about doubled; the multi-degree-of-freedom wrist joint adopts a rope driving mode, and has the advantages of simple structure, low tail end inertia, high flexibility and high response speed.

The rail holder 200 carries the two first arc-shaped rails 310 to swing reversely around the first mounting shaft 110: the rail seat 200 may swing around the first mounting shaft 110 with the two first arc-shaped rails 310 in opposite directions; alternatively, the rail housing 200 can swing back around the first mounting axle 110 with the two first arcuate rails 310.

The rail housing 200 carries two second arc-shaped rails 320 to swing around the second mounting shaft 120 in opposite directions: the rail seat 200 may carry the two second arc-shaped rails 320 to swing around the second mounting shaft 120 in opposite directions; alternatively, the rail holder 200 may swing back around the second mounting shaft 120 with the two second arc-shaped rails 320.

As shown in fig. 3, the two first mounting shafts 110 are located on the first member, the two second mounting shafts 120 are located on the second member, and after the first member is inserted on the second member, the first member and the second member are fixed together by four screws distributed uniformly in the circumferential direction.

In some examples, as shown in fig. 1, 2, 4 and 5, the first axes a of the two first mounting shafts 110 are collinear (the two first arc-shaped guide rails 310 form a first degree of rotational freedom), the second axes b of the two second mounting shafts 120 are collinear (the two second arc-shaped guide rails 320 form a second degree of rotational freedom), the third axes of the two third pulley assemblies 130 are collinear, and the first axis a, the second axis b and the third axes intersect perpendicularly at a point, so that the wrist joint has no singular point in the working space, can realize continuous movement at any attitude angle in the working range, has no problem of jamming of the wrist joint in movement at certain angles, and can better complete the task required to be executed by the wrist joint. The two first mounting shafts 110 are spaced 180 degrees apart, the two second mounting shafts 120 are spaced 180 degrees apart, and adjacent first and

second mounting shafts

110, 120 are spaced 90 degrees apart.

In some examples, as shown in fig. 1, 2, 4, and 5, the first arcuate rail 310 is a semi-circular arcuate rail, the axis of the first arcuate rail 310 coinciding with the second axis b; the second arc-shaped guide rail 320 is a semicircular arc-shaped guide rail, and the axis of the second arc-shaped guide rail 320 is overlapped with the first axis a; the first arc-shaped guide rail 310 and the second arc-shaped guide rail 320 are in a non-coplanar vertical intersection.

In some exemplary embodiments, as shown in fig. 2 and 4, the multiple degree of freedom wrist joint further comprises: the fifth rope is wound around one of the two third pulley assemblies 130 and the two first pulley assemblies 111, and the matching structures of the fifth rope, one of the two third pulley assemblies 130 and the two first pulley assemblies 111 control the two first arc-shaped guide rails 310 to synchronously swing in opposite directions or synchronously swing in opposite directions around the first mounting shaft 110.

In some embodiments, as shown in fig. 2 and 4, the fifth rope includes a first sub-rope 410 and a second sub-rope 420, the first sub-rope 410 is wound around one of the two first pulley assemblies 111 and one of the two third pulley assemblies 130, and the second sub-rope 420 is wound around the other of the two first pulley assemblies 111 and one of the two third pulley assemblies 130 (as understood in conjunction with fig. 7), and the first sub-rope 410 and the second sub-rope 420 are prevented from being wound around each other. The first sub rope 410 and the second sub rope 420 wind in the same direction on one of the two third pulley assemblies 130, and the first sub rope 410 and the second sub rope 420 wind in opposite directions on the two first pulley assemblies 111. Thus, when the guide rail holder 200 carries the two first arc-shaped guide rails 310 to swing reversely around the first mounting shaft 110, the cooperation structure of the fifth rope, one of the two third pulley assemblies 130 and the two first pulley assemblies 111 can control the two first arc-shaped guide rails 310 to swing synchronously and reversely around the first mounting shaft 110 (i.e., synchronously swing towards each other or synchronously swing away from each other). Both ends of the first sub-rope 410 may be respectively fixed to the first pulley assembly 111 and the third pulley assembly 130 wound around the first sub-rope; or, two ends of the first sub-string 410 may be connected; both ends of the second sub-rope 420 are respectively fixed on the first pulley assembly 111 and the third pulley assembly 130 wound around the second sub-rope; or, two ends of the second sub-string 420 may be connected; the above objectives can be achieved without departing from the design concept of the present invention, and therefore, the details are not repeated herein and all of the objectives should fall within the protection scope of the present application.

In some exemplary embodiments, as shown in fig. 2, 4 and 7, the multiple degree of freedom wrist joint further comprises: and the sixth rope is wound on the other one of the two third pulley assemblies 130 and the two second pulley assemblies 121, and the matching structures of the sixth rope, the other one of the two third pulley assemblies 130 and the two second pulley assemblies 121 control the two second arc-shaped guide rails 320 to synchronously swing in opposite directions or synchronously swing in opposite directions around the second mounting shaft 120.

In some embodiments, as shown in fig. 2, 4 and 7, the sixth rope includes a third sub-rope 430 and a fourth sub-rope 440, the third sub-rope 430 being looped around one of the two second sheave assemblies 121 and the other of the two third sheave assemblies 130, and the fourth sub-rope 440 being looped around the other of the two second sheave assemblies 121 and the other of the two third sheave assemblies 130. The third sub rope 430 and the fourth sub rope 440 wind in the same direction on the other of the two third sheave assemblies 130, and the third sub rope 430 and the fourth sub rope 440 wind in opposite directions on the two second sheave assemblies 121. Thus, when the rail holder 200 carries the two second arc-shaped guide rails 320 to swing reversely around the second mounting shaft 120, the matching structure of the sixth rope, the other of the two third pulley assemblies 130 and the two second pulley assemblies 121 can control the two second arc-shaped guide rails 320 to swing synchronously and reversely around the second mounting shaft 120 (i.e., synchronously swing towards each other or synchronously swing away from each other). Both ends of the third sub-rope 430 are respectively fixed on the second pulley assembly 121 and the third pulley assembly 130 wound around the third sub-rope; or, both ends of the third sub-string 430 may be connected; two ends of the fourth sub-rope 440 may be fixed to the second pulley assembly 121 and the third pulley assembly 130 wound around the fourth sub-rope respectively; or, both ends of the fourth sub rope 440 may be connected; the above objectives can be achieved without departing from the design concept of the present invention, and therefore, the details are not repeated herein and all of the objectives should fall within the protection scope of the present application.

In some embodiments, two sets of wheel grooves (not shown) are provided on each third pulley assembly 130. The first sub rope 410, the second sub rope 420, the third sub rope 430 and the fourth sub rope 440 are correspondingly wound in four sets of wheel grooves one by one, so that the first sub rope 410 and the second sub rope 420 are more easily prevented from being wound and the third sub rope 430 and the fourth sub rope 440 are more easily prevented from being wound.

In some exemplary embodiments, as shown in fig. 1 and 2, each rail seat 200 is provided with two fourth pulley assemblies 230 and two fifth pulley assemblies 240 at intervals and uniformly distributed along the circumferential direction, the four fourth pulley assemblies 230 are located on the outer sides of the two first arc-shaped guide rails 310 in pairs, and the four fifth pulley assemblies 240 are located on the outer sides of the two second arc-shaped guide rails 320 in pairs.

As shown in fig. 2, the first rope of the first rope driving mechanism 510 is wound around the two fourth pulley assemblies 230 located at one side of the two rail brackets 200, and the second rope of the second rope driving mechanism 520 is wound around the two fourth pulley assemblies 230 located at the other side of the two rail brackets 200. The first rope driving mechanism 510 is controlled to pull the first rope, the second rope driving mechanism 520 is controlled to release the second rope, and then the matching structures of the fifth rope, one of the two third pulley assemblies 130 and the two first pulley assemblies 111 are matched to control the two first arc-shaped guide rails 310 to synchronously and reversely swing around the first mounting shaft 110, so that the two first arc-shaped guide rails 310 can synchronously move in the opposite directions (or synchronously move in the opposite directions); the first cable driving mechanism 510 is controlled to release the first cable, the second cable driving mechanism 520 is controlled to pull the second cable, and the fifth cable, one of the two third pulley assemblies 130 and the two first pulley assemblies 111 are matched to control the two first curved guide rails 310 to synchronously swing reversely around the first mounting shaft 110, so that the two first curved guide rails 310 synchronously move backwards (or synchronously move towards each other).

As shown in fig. 2, the third rope of the third rope driving mechanism 530 is wound around the two fifth pulley assemblies 240 located on one side of the two rail brackets 200, and the fourth rope of the fourth rope driving mechanism 540 is wound around the two fifth pulley assemblies 240 located on the other side of the two rail brackets 200. The third rope driving mechanism 530 is controlled to pull the third rope, the fourth rope driving mechanism 540 is controlled to release the fourth rope, and the matching structures of the sixth rope, the other of the two third pulley assemblies 130 and the two second pulley assemblies 121 are matched to control the two second arc-shaped guide rails 320 to synchronously and reversely swing around the second mounting shaft 120, so that the two second arc-shaped guide rails 320 synchronously move in the opposite direction (or synchronously move in the opposite direction); the third rope driving mechanism 530 is controlled to release the third rope, the fourth rope driving mechanism 540 is controlled to pull the fourth rope, and the two second arc-shaped guide rails 320 are controlled to synchronously and reversely swing around the second mounting shaft 120 by matching with the sixth rope, the other one of the two third pulley assemblies 130 and the matching structures of the two second pulley assemblies 121, so that the two second arc-shaped guide rails 320 synchronously move back to back (or synchronously move in opposite directions).

In some embodiments, as shown in fig. 1 to 4 and 6, the ends of both first mounting shafts 110 are provided with the first threading structure 611 and the ends of both second mounting shafts 120 are provided with the second threading structure 621.

As shown in fig. 2, the first rope of the first rope driving mechanism 510 is wound around two fourth pulley assemblies 230 and a first threading structure 611 located at one side of the two rail brackets 200; as shown in fig. 2, the second rope of the second rope driving mechanism 520 is wound around two fourth pulley assemblies 230 and a first threading structure 611 located at the other side of the two rail brackets 200; the first threading structure 611 serves to ensure the reliability of the driving connection and the motion reliability between the first rope, the second rope, and the fourth pulley assembly 230. The first threading structure 611 may be configured as a threading hole or a threading groove.

As shown in fig. 2, the third rope of the third rope driving mechanism 530 is wound around the two fifth pulley assemblies 240 and the second threading structure 621 which are located at one side of the two rail brackets 200; as shown in fig. 2, the fourth rope of the fourth rope driving mechanism 540 is wound around two fifth pulley assemblies 240 and a second threading structure 621 which are located at the other side of the two rail mounts 200; the second threading structure 621 is used to ensure the reliability of the transmission connection and the action between the third rope, the fourth rope and the fifth pulley assembly 240. The second threading structure 621 may be a threading hole or a threading groove.

In some embodiments, as shown in fig. 1-4 and 6, the multiple degree of freedom wrist joint further comprises: the two first mounting brackets 610 are located at the outer sides of the two first arc rails 310 and are respectively and fixedly connected to the ends of the two first arc rails 310 (i.e. one first mounting bracket 610 is fixed at one end of one first arc rail 310, and the other first mounting bracket 610 is fixed at the other end of the other first arc rail 310), and the two first threading structures 611 are respectively located on the two first mounting brackets 610.

Of course, two first mounting brackets 610 may be fixed to two end portions of one of the first arc-shaped guide rails 310, which may also achieve the purpose of the present application, and the purpose of the present application does not depart from the design concept of the present invention, and therefore, the present application is not described herein again and should also fall within the protection scope of the present application.

In some embodiments, as shown in fig. 1, 2, and 4, the multiple degree of freedom wrist joint further comprises: the two second mounting brackets 620 are located outside the two second arc-shaped guide rails 320 and are respectively and fixedly connected to the ends of the two second arc-shaped guide rails 320 (i.e. one second mounting bracket 620 is fixed to one end of one second arc-shaped guide rail 320, and the other second mounting bracket 620 is fixed to the other end of the other second arc-shaped guide rail 320), and the two second threading structures 621 are respectively located on the two second mounting brackets 620.

Of course, two second mounting brackets 620 may be fixed at two end portions of one of the second arc-shaped guide rails 320, which may also achieve the purpose of the present application, and the purpose of the present application does not depart from the design concept of the present invention, and therefore, the details are not described herein and should also fall within the protection scope of the present application.

In some embodiments, as shown in fig. 2, the multiple degree of freedom wrist joint further comprises: a first rope driving mechanism 510, wherein a first rope is wound around the two fourth pulley assemblies 230 and the first threading structure 611 which are positioned at one side of the two rail holders 200; and a second rope driving mechanism 520, wherein the second rope is wound on the two fourth pulley assemblies 230 and the first threading structure 611 which are positioned at the other side of the two guide rail bases 200; the first rope driving mechanism 510 and the second rope driving mechanism 520 are used for driving the two rail holders 200 to carry the two second arc-shaped rails 320 to swing oppositely towards each other or swing oppositely away from each other around the second mounting shaft 120.

In some embodiments, as shown in fig. 2, the multiple degree of freedom wrist joint further comprises: a third rope driving mechanism 530, the third rope of which is wound around the two fifth pulley assemblies 240 and the second threading structure 621 which are located at one side of the two rail holders 200; and a fourth rope driving mechanism 540, the fourth rope of which is wound around the two fifth pulley assemblies 240 and the second threading structure 621 on the other side of the two rail holders 200; the third rope driving mechanism 530 and the fourth rope driving mechanism 540 are used for driving the two guide rail bases 200 to drive the two first arc-shaped guide rails 310 to swing oppositely or oppositely and reversely around the first mounting shaft 110.

The multi-degree-of-freedom wrist joint adopts a rope driving mode, is simple in structure, does not have singular points in a working space, can realize continuous motion of any posture angle in a working range, does not have the problem that the wrist joint is stuck in motion of certain angles, can better complete tasks required to be executed, and has the advantages of low terminal inertia, high flexibility and high response speed.

In some embodiments, as shown in fig. 5, each rail housing 200 may define a first arc-shaped track 210 by four first rolling bearings 710 and a second arc-shaped track 220 by four second rolling bearings 720, wherein the first arc-shaped rail 310 moves circumferentially along the first arc-shaped track 210 in a rolling friction manner and the second arc-shaped rail 320 moves circumferentially along the second arc-shaped track 220 in a rolling friction manner.

In some embodiments, as shown in fig. 1-4, the first and

second pulley assemblies

111 and 121 each include a pulley and a connector cylinder fixedly connected for rotation with the pulley. The third pulley assembly 130, the fourth pulley assembly 230, and the fifth pulley assembly 240 each include a pulley.

As shown in fig. 2, the multi-degree-of-freedom wrist joint provided by the invention is a unique mechanism based on a special mechanical structure and a symmetrical concept, and can maintain symmetry. The multi-degree-of-freedom wrist joint can rotate in two dimensions, simulates a wrist joint, can be used as a flexible coupling for connecting two shafts at constant angular speed, and can be bent to more than 90 degrees or even to 120 degrees. If a third rotational degree of freedom is added, a spherical hinge mechanism can be simulated, and the purpose that the driving connecting rod moves to another point from any point along any track without any problem is achieved.

The manipulator (not shown in the figures) provided by the embodiment of the invention comprises the multi-degree-of-freedom wrist joint described in any embodiment.

The manipulator has all the advantages of the multi-degree-of-freedom wrist joint provided by any one of the above embodiments, and is not described herein again.

The robot (not shown in the figures) provided by the embodiment of the invention comprises the manipulator described in any embodiment.

The robot has all the advantages of the manipulator provided by any of the above embodiments, and the description thereof is omitted.

In summary, in the multi-degree-of-freedom wrist joint provided in the embodiment of the present invention, the fifth rope is wound around one of the two first pulley assemblies and the two third pulley assemblies, the control guide rail base drives the two first arc-shaped guide rails to swing reversely around the first installation shaft, and the matching structure of the fifth rope, the two first pulley assemblies and the one of the two third pulley assemblies controls the two first arc-shaped guide rails to swing synchronously and reversely around the first installation shaft, so as to implement synchronous motion of the two first arc-shaped guide rails, and the response speed thereof is significantly increased, that is, the response speed is increased by about two times; a sixth rope is wound on the other one of the two second pulley assemblies and the two third pulley assemblies, the guide rail seat is controlled to drive the two second arc-shaped guide rails to reversely swing around the second mounting shaft, and the two second arc-shaped guide rails are controlled to synchronously and reversely swing around the second mounting shaft through a matching structure of the sixth rope, the two second pulley assemblies and the other one of the two third pulley assemblies, so that synchronous action of the two second arc-shaped guide rails is realized, the response speed is obviously improved, and the response speed is about doubled; the multi-degree-of-freedom wrist joint adopts a rope driving mode, is simple in structure and has the advantages of low terminal inertia, high flexibility and high response speed.

In the description of the embodiments of the present invention, unless otherwise explicitly specified or limited, the terms "connected," "directly connected," "indirectly connected," "fixedly connected," "mounted," and "mounted" are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; the terms "mounted," "connected," and "fixedly connected" may refer to a direct connection, an indirect connection through intervening media, and a connection between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Although the embodiments of the present invention have been described above, the above description is only for the convenience of understanding the present invention, and is not intended to limit the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, and all equivalent structural changes made by using the contents of the specification and drawings, or any other related technical fields, which are directly or indirectly applied to the present invention, are included in the scope of the present invention.

Claims

1. A multi-degree-of-freedom wrist joint is characterized by comprising:

the central piece is alternately provided with two first mounting shafts and two second mounting shafts at intervals along the circumferential direction, the two first mounting shafts are rotatably sleeved with first pulley assemblies, the two second mounting shafts are rotatably sleeved with second pulley assemblies, and both axial ends of the central piece are rotatably provided with third pulley assemblies;

the central piece is positioned between the two guide rail seats, and a first arc-shaped rail and a second arc-shaped rail which are intersected are arranged on each guide rail seat;

the two first arc-shaped guide rails are respectively and movably arranged on the two first arc-shaped rails, two ends of each first arc-shaped guide rail are respectively hinged to the two first mounting shafts, and the two first pulley assemblies are respectively and fixedly connected to the end parts of the two first arc-shaped guide rails; and

two second arc-shaped guide rails are movably arranged on the two second arc-shaped rails respectively, two ends of each second arc-shaped guide rail are hinged to the two second mounting shafts respectively, and the two second pulley assemblies are fixedly connected to the end portions of the two second arc-shaped guide rails respectively.

2. The multi-degree-of-freedom wrist joint according to claim 1, wherein each of the guide rail seats is alternately provided with two fourth pulley assemblies and two fifth pulley assemblies at intervals along the circumferential direction, the four fourth pulley assemblies are located on the outer sides of the two first arc-shaped guide rails in a pairwise corresponding manner, and the four fifth pulley assemblies are located on the outer sides of the two second arc-shaped guide rails in a pairwise corresponding manner.

3. The multi-degree-of-freedom wrist joint according to claim 2, wherein first threading structures are provided at ends of the two first mounting shafts, and second threading structures are provided at ends of the two second mounting shafts.

4. The multiple degree of freedom wrist joint of claim 3, further comprising:

the two first mounting frames are positioned on the outer sides of the two first arc-shaped guide rails and are respectively and fixedly connected to the end parts of the two first arc-shaped guide rails, and the two first threading structures are respectively positioned on the two first mounting frames; and

the two second mounting frames are positioned on the outer sides of the two second arc-shaped guide rails and fixedly connected to the end portions of the two second arc-shaped guide rails respectively, and the two second threading structures are positioned on the two second mounting frames respectively.

5. The multiple degree of freedom wrist joint of claim 3, further comprising:

the first rope of the first rope driving mechanism is wound on the two fourth pulley assemblies positioned on one side of the two guide rail seats and the first threading structure; and

the second rope of the second rope driving mechanism is wound on the two fourth pulley assemblies positioned on the other sides of the two guide rail seats and the first threading structure;

the first rope driving mechanism and the second rope driving mechanism are used for driving the two guide rail seats to drive the two second arc-shaped guide rails to swing oppositely or oppositely and reversely around the second mounting shaft.

6. The multi-degree-of-freedom wrist joint according to claim 3, further comprising:

the third rope of the third rope driving mechanism is wound on the two fifth pulley assemblies positioned on one side of the two guide rail seats and the second threading structure; and

a fourth rope of the fourth rope driving mechanism is wound on the two fifth pulley assemblies positioned on the other sides of the two guide rail seats and the second threading structure;

the third rope driving mechanism and the fourth rope driving mechanism are used for driving the two guide rail seats to drive the two first arc-shaped guide rails to swing oppositely or oppositely and reversely around the first installation shaft.

7. The multiple degree of freedom wrist joint of any one of claims 1 to 6, further comprising:

the fifth rope is wound on one of the two first pulley assemblies and the two third pulley assemblies and is arranged to control the two first arc-shaped guide rails to synchronously swing around the first mounting shaft in opposite directions or synchronously swing around the first mounting shaft in opposite directions;

and the sixth rope is wound on the other one of the two second pulley assemblies and the two third pulley assemblies and is arranged to control the two second arc-shaped guide rails to synchronously swing in opposite directions or synchronously swing in opposite directions around the second mounting shaft.

8. The multi-degree-of-freedom wrist joint according to claim 7,

the fifth rope comprises a first sub rope and a second sub rope, the first sub rope is wound on one of the two first pulley assemblies and one of the two third pulley assemblies, and the second sub rope is wound on the other of the two first pulley assemblies and one of the two third pulley assemblies;

the sixth rope includes a third sub-rope and a fourth sub-rope, the third sub-rope is wound on one of the two second sheave assemblies and the other of the two third sheave assemblies, and the fourth sub-rope is wound on the other of the two second sheave assemblies and the other of the two third sheave assemblies.

9. The multi-degree-of-freedom wrist joint according to any one of claims 1 to 6,

the first axes of the two first mounting shafts are collinear, the second axes of the two second mounting shafts are collinear, the third axes of the two third pulley assemblies are collinear, and the first axis, the second axis and the third axes are perpendicularly intersected at one point;

wherein: the first arc-shaped guide rail is a semicircular arc-shaped guide rail, and the axis of the first arc-shaped guide rail is superposed with the second axis; the second arc-shaped guide rail is a semi-arc-shaped guide rail, and the axis of the second arc-shaped guide rail is coincided with the first axis.

10. A manipulator, comprising a multiple degree of freedom wrist joint according to any one of claims 1 to 9.

11. A robot comprising the manipulator of claim 10.