A three-degree-of-freedom decoupled wrist

Abstract

The application discloses a three-degree-of-freedom decoupling wrist, relates to the technical field of humanoid wrist robots, and comprises a static platform base, a pointing motion branch, an intermediate rotary branch, a moving platform, a guide wheel assembly and a driving rope assembly. The pointing motion branch is arranged above the static platform base and comprises a pitching support seat, a yawing support seat, a pitching driving wheel, a yawing driving wheel and a connecting rod assembly. The intermediate rotary branch is installed between the static platform base and the moving platform. The guide wheel assembly is installed on the static platform base. The driving rope assembly comprises a first driving rope, a second driving rope and a third driving rope, and the driving rope assembly is adapted to be wound and connected between the guide wheel assembly and the pointing motion branch. The decoupling wrist is adapted to rotate and rotate around the whole circle in three-degree-of-freedom motion directions through the driving rope assembly. The three-degree-of-freedom decoupling wrist is simple and compact in structure, has no singular shape position in a working space, and converges the axes of all joints at a point, so that the rotary motion of the wrist is more easily realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of humanoid wrist robots, in particular to a three-degree-of-freedom decoupled wrist. BACKGROUND

[0002] A humanoid wrist is an important component of a humanoid robot hand, responsible for simulating the flexible movements of a human hand, including rotation, bending, and swinging. The design of the wrist directly affects the operating precision, adaptability, and flexibility of the robot arm. In performing complex tasks such as fine assembly, surgical assistance, or human-computer interaction, a highly biomimetic wrist can provide a similar range of motion and control force to a human hand, greatly improving the performance of the robot arm.

[0003] Chinese invention patent with publication number CN107351064A discloses a two-degree-of-freedom parallel humanoid wrist, which uses two half-circular arc-shaped follower pointing rods. The motor drives the half-circular arc pointing rods through a gear, realizing two-degree-of-freedom motion of the mechanism, which is flexible and precise. However, the rod parts have serious friction and wear, resulting in short service life. It is also difficult to fix the cable at the end of the installation actuator.

[0004] Chinese invention patent with publication number CN117773995A discloses a three-degree-of-freedom robot wrist, which includes a rotary mechanism, a differential drive mechanism, and a differential transmission mechanism. The robot wrist has the characteristics of flexible motion range, strong load capacity, and compact structure. However, it has a large mass and is difficult to install an end effector through a cable, which is not convenient for high-speed motion.

[0005] Chinese invention patent with publication number CN214724204U discloses a rope-driven wrist module based on a three-degree-of-freedom series-parallel hybrid mechanism. The wrist module is composed of a three-degree-of-freedom series-parallel module and a drive control integrated module. The three-degree-of-freedom series-parallel module includes a spherical pure rolling parallel mechanism and a tension amplification mechanism. The spherical pure rolling parallel mechanism realizes two-degree-of-freedom spherical motion of the wrist, and the lower platform of the parallel mechanism is designed as one degree of rotational freedom, forming a series-parallel hybrid mechanism. The tension amplification mechanism ensures lightweight while not losing stiffness. The drive control integrated module integrates motors, drivers, and controllers to form an independent electromechanical system. By combining the advantages of rope driving and modularity, the module has the advantages of light weight, reconfigurability, and good compliance. The proposed series-parallel hybrid mechanism has the same degree of freedom configuration as a human wrist and can achieve high-fidelity humanoid wrist motion. However, the hybrid structure has too many connecting rods, the structure is complex, and it cannot complete a full rotation. The mathematical model of forward and inverse solutions is complex, which is not conducive to control.

[0006] Through comprehensive analysis, the existing humanoid wrists have the following problems:

[0007] Firstly, it is difficult to achieve a full rotation, or the full rotation needs the cooperation of each drive, the control is complex, and the precision is poor.

[0008] Secondly, the existing wrist transmission mechanism is complex, and the mass is large, which is not conducive to lightweight design.

[0009] Thirdly, most of the existing wrists cannot achieve closed-loop rope driving, and the driving system is complex.

[0010] Fourthly, the existing wrist cannot simultaneously satisfy three-axis rotation, easy full rotation, closed-loop rope driving, and simple mathematical model, and there is a significant shortcoming in application. SUMMARY

[0011] Therefore, in view of the technical problems existing in the prior art, the purpose of the present application is to provide a three-degree-of-freedom decoupling wrist to satisfy simple and compact structure, and three sets of driving ropes can achieve three-degree-of-freedom rotation, large wrist rolling motion space, and full rotation action.

[0012] To solve the above problems, the technical scheme of the present application provides a three-degree-of-freedom decoupling wrist, comprising:

[0013] A static platform base;

[0014] A dynamic platform;

[0015] A pointing motion branch arranged above the static platform base, the pointing motion branch comprising a pitch support seat, a yaw support seat, a pitch driving wheel, a yaw driving wheel and a linkage assembly, the pitch support seat and the yaw support seat being fixedly connected with the static platform base; the pitch driving wheel is connected with the pitch support seat through a first revolute pair, and the yaw driving wheel is connected with the yaw support seat through a second revolute pair;

[0016] An intermediate rotation branch installed between the static platform base and the dynamic platform;

[0017] A guide wheel assembly installed on the static platform base;

[0018] A driving rope assembly comprising a first driving rope, a second driving rope and a third driving rope which are paired and closed-loop driving the same joint, the driving rope assembly being adapted to be wound between the guide wheel assembly, the pointing motion branch and the intermediate rotation branch;

[0019] The decoupling wrist is adapted to rotate and full rotate in three-degree-of-freedom motion directions through the driving rope assembly.

[0020] Preferably, the linkage assembly comprises a first linkage, a second linkage, a third linkage and a fourth linkage, wherein:

[0021] The first connecting rod is connected with the second connecting rod through a third rotating pair; the second connecting rod is connected with the third connecting rod through a fourth rotating pair; the third connecting rod and the fourth connecting rod are connected through a fifth rotating pair;

[0022] The first connecting rod is fixedly connected with the deflection driving wheel through a transmission shaft, the third connecting rod is fixedly connected with the moving platform, and the fourth connecting rod is fixedly connected with the pitching driving wheel through a transmission shaft;

[0023] The fourth rotating pair and the fifth rotating pair are both located on the third connecting rod, and the fourth rotating pair and the fifth rotating pair have an included angle therebetween.

[0024] Preferably, the intermediate rotary branch comprises a base flange, a rotary driving wheel, a rotary connecting flange and a universal hinge, wherein:

[0025] The universal hinge is composed of a universal hinge lower fork, a universal hinge upper fork and a universal hinge center block;

[0026] The base flange is fixedly connected with the static platform base, the base flange is connected with the rotary driving wheel through a sixth rotating pair, and the rotary driving wheel is fixedly connected with the universal hinge lower fork;

[0027] The sixth rotating pair is perpendicular to the static platform base in direction, and the sixth rotating pair is adapted to whole-circle rotation;

[0028] The universal hinge upper fork passes through the center of the moving platform and is connected with the moving platform through a seventh rotating pair.

[0029] Preferably, the first rotating pair, the second rotating pair, the third rotating pair, the fourth rotating pair, the fifth rotating pair, the sixth rotating pair and the seventh rotating pair converge at a point, the convergence center coincides with the rotation center of the universal hinge, and the first rotating pair and the second rotating pair are both horizontally fixed in direction.

[0030] Preferably, the guide wheel assembly comprises a first guide wheel group, a second guide wheel group, a third guide wheel group and a fourth guide wheel group;

[0031] Two ends of the first guide wheel group are respectively and symmetrically provided with a fifth pulley and a ninth pulley and a sixth pulley and a tenth pulley;

[0032] Two ends of the second guide wheel group are respectively and symmetrically provided with a thirteenth pulley and a fifteenth pulley and a fourteenth pulley and a sixteenth pulley;

[0033] Two ends of the third guide wheel group are respectively and symmetrically provided with a seventh pulley and an eleventh pulley and an eighth pulley and a twelfth pulley;

[0034] The third pulley and the fourth pulley are symmetrically arranged at two ends of the fourth guide wheel group respectively, and the fourth guide wheel group is connected to the static platform base through a guide wheel base.

[0035] Preferably, the static platform base is a reverse U-shaped structure, the middle of the reverse U-shaped structure transversely crosses the first cross beam and the second cross beam, the first cross beam is provided with the first guide wheel group and the second guide wheel group, and the second cross beam is provided with the third guide wheel group and the fourth guide wheel group.

[0036] Preferably, the starting ends of the two first driving ropes are fixed to the knot holes of the pitching driving wheel, the other ends pass through the first wire hole and the second wire hole of the static platform base downward, pass through the lower sides of the sixth pulley and the tenth pulley, pass through the upper sides of the fifth pulley and the ninth pulley, and pass through the first guide wheel group; the terminal ends of the two first driving ropes extend downward to the output ends of the first driving part in a front-rear symmetric manner.

[0037] Preferably, the starting ends of the two second driving ropes are fixed to the knot holes of the deflection driving wheel, the other ends pass through the third wire hole and the fourth wire hole of the static platform base, pass through the lower sides of the fourteenth pulley and the sixteenth pulley, pass through the upper sides of the thirteenth pulley and the fifteenth pulley, and pass through the second guide wheel group; the terminal ends of the two second driving ropes extend downward to the output ends of the second driving part in a front-rear symmetric manner.

[0038] Preferably, the starting ends of the two third driving ropes are fixed to the knot holes of the rotation driving wheel, the other ends pass through the third pulley and the fourth pulley of the fourth guide wheel group, then pass through the fifth wire hole and the sixth wire hole of the static platform base, pass through the lower sides of the eighth pulley and the twelfth pulley, pass through the upper sides of the seventh pulley and the eleventh pulley, and pass through the third guide wheel group; the terminal ends of the two third driving ropes extend downward to the output ends of the third driving part in a front-rear symmetric manner.

[0039] Preferably, the universal hinge lower fork and the universal hinge upper fork are provided with through holes in the long rod direction, and the universal hinge center block is provided with a through hole and is suitable for passing through a cable.

[0040] Compared with the prior art, the present application has the following beneficial effects:

[0041] 1、The three-degree-of-freedom decoupling wrist in the application realizes the motion decoupling of three degrees of freedom through its unique structural design, wherein the layout of components such as the static platform base, the pointing motion branch, the intermediate rotary branch and the moving platform is reasonable and compact, the pitch support seat and the yaw support seat are fixedly connected with the static platform base, and the stability of the pointing motion branch is ensured; the intermediate rotary branch is installed between the static platform base and the moving platform, effectively connecting and supporting the two, so that the entire wrist structure maintains good rigidity and reliability during the motion process, reduces the motion error and failure risk caused by structural deformation or looseness, and is conducive to long-term stable operation in a harsh working environment; the pointing motion branch comprises two driving wheels of pitch and yaw, and is connected with the corresponding support seat through the first rotary pair and the second rotary pair respectively, which enables the pitch and yaw motions to be carried out independently without interference. At the same time, the setting of the intermediate rotary branch further enhances the effect of motion decoupling, so that the wrist will not have a coupling effect on the pitch and yaw motions when performing a full rotation, thereby accurately controlling the motion of the wrist in three degrees of freedom, meeting the requirements of complex operation tasks on motion accuracy. With the aid of the driving rope assembly and the guide wheel assembly installed on the static platform base, the decoupling wrist can rotate and perform a full rotation in three degrees of freedom. This design makes the wrist have greater motion flexibility and can cover a wider range of motion, adapt to different angle and position operation requirements, and easily reach and operate target objects at different spatial positions and postures, improving the flexibility and efficiency of the operation. The use of the driving rope assembly provides a simple and effective way for the driving of the wrist. By controlling the winding and release of the driving rope, the pointing motion branch can be accurately driven to perform pitch, yaw and full rotation of the intermediate rotary branch, and the structure of the driving system is relatively simple, facilitating the integration with the control system.

[0042] 2、The three-degree-of-freedom decoupling wrist driven by a light-weight rope wheel based on the convergence of rotation axes has three degrees of freedom and is driven by three pairs of closed-loop ropes, so that the driving system is simple and the structure is light-weight; the parallel mechanism design has fewer rods and a simple structure, thereby enhancing the rigidity of the wrist and making it have better operation stability and balance; through the special rotary branch design, the other branches can be fixed when the wrist performs a rotary motion, thereby improving the attitude capability of the wrist; a long cable can pass through the middle of the wrist, which is beneficial to the installation of the end effector and ensures the aesthetics and safety of the overall mechanism. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 FIG. 1 is a three-dimensional structural schematic diagram of the three-degree-of-freedom decoupling wrist in the embodiment of the application;

[0044] Figure 2 FIG. 2 is a front structural schematic diagram of the three-degree-of-freedom decoupling wrist in the embodiment of the application;

[0045] Figure 3 Figure 3 is a schematic view of the back structure of a three-degree-of-freedom decoupling wrist in an embodiment of the present application;

[0046] Figure 4 Figure 4 is a schematic view of the structure of a static platform base in an embodiment of the present application;

[0047] Figure 5 Figure 5 is a schematic view of the structure of a rotary motion branch in an embodiment of the present application.

[0048] Legend of reference signs:

[0049] 1 - static platform base; 2 - pointing motion branch; 3 - rotary motion branch; 4 - moving platform;

[0050] a - pitch support seat; b - yaw support seat; c - base flange; d - rotary drive wheel; e - rotary connection flange; f - lower cardan joint fork; g - cardan joint center block; h - upper cardan joint fork;

[0051] L1 - first connecting rod; L2 - second connecting rod; L3 - third connecting rod; L4 - fourth connecting rod;

[0052] R1 - first revolute pair; R2 - second revolute pair; R3 - third revolute pair; R4 - fourth revolute pair; R5 - fifth revolute pair; R6 - sixth revolute pair; R7 - seventh revolute pair;

[0053] U - cardan joint;

[0054] Z1 - first guide wheel set; Z2 - second guide wheel set; Z3 - third guide wheel set; Z4 - fourth guide wheel set;

[0055] S1 - first drive rope; S2 - second drive rope; S3 - third drive rope;

[0056] P1 - pitch drive wheel; P2 - yaw drive wheel; P3 - third pulley; P4 - fourth pulley; P5 - fifth pulley; P6 - sixth pulley; P7 - seventh pulley; P8 - eighth pulley; P9 - ninth pulley; P10 - tenth pulley; P11 - eleventh pulley; P12 - twelfth pulley; P13 - thirteenth pulley; P14 - fourteenth pulley; P15 - fifteenth pulley; P16 - sixteenth pulley;

[0057] K1 - first wire guide hole; K2 - second wire guide hole; K3 - third wire guide hole; K4 - fourth wire guide hole; K5 - fifth wire guide hole; K6 - sixth wire guide hole;

[0058] H1 - first cross beam; H2 - second cross beam. DETAILED DESCRIPTION

[0059] The technical solutions of the present application will be clearly and completely described below with reference to the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, but not all of them. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the protection scope of the present application.

[0060] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium, or internal communication of two elements, it can be wireless connection, or wired connection. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0061] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as there is no conflict.

[0062] Please refer to Figures 1-5 As shown in the drawings, the embodiment of the present application provides a three-degree-of-freedom decoupling wrist, which comprises a static platform base 1, a pointing motion branch 2, an intermediate rotary branch 3, a moving platform 4, a guide wheel assembly and a driving rope assembly, wherein:

[0063] The static platform base 1 is the fixed part of the whole structure, and the moving platform 4 is used for carrying lightweight connecting rods and guide wheels, reducing inertia and improving dynamic response speed.

[0064] The pointing motion branch 2 is used for processing pitch and yaw, and the pointing motion branch 2 in the embodiment is arranged above the static platform base 1, and the pointing motion branch 2 comprises a pitch support seat a, a yaw support seat b, a pitch driving wheel P1, a yaw driving wheel P2 and a connecting rod assembly, the pitch support seat a and the yaw support seat b are fixedly connected with the static platform base 1; the pitch driving wheel P1 is connected with the pitch support seat a through a first revolute pair R1, and the yaw driving wheel P2 is connected with the yaw support seat b through a second revolute pair R2.

[0065] The intermediate rotary branch 3 adopts an independent structure and is used for allowing the moving platform 4 to rotate around the whole circle, as a preferred mode of the embodiment, the intermediate rotary branch 3 is installed between the static platform base 1 and the moving platform 4, allowing the central axis passing through the moving platform 4 to realize 360° continuous rotation, expanding the working space and being suitable for scenes requiring whole circle operation; the guide wheel assembly is installed on the static platform base 1 and is used for helping the driving rope to reduce friction and ensure the correct path of the rope to avoid interference and wear problems with other components.

[0066] The driving rope assembly includes a pair of closed-loop driving ropes S1, S2 and S3 driving the same joint, each degree of freedom is cooperated by two driving ropes, rotation is realized by differential manner, and the driving rope assembly is suitable for winding connection between the guide wheel assembly and the pointing motion branch 2. The driving rope assembly is wound by the guide wheel, and the driving part is placed on the base, the mass of the moving part is reduced, and the dynamic performance is improved. In addition, the complexity of the mechanical structure can be reduced by using the driving rope and the guide wheel, so that the wrist is lighter and the response is faster.

[0067] The decoupling wrist is suitable for rotation and whole-circle rotation in three degrees of freedom motion directions by the driving rope assembly.

[0068] Therefore, the decoupling wrist is driven by the split branch structure and the rope, realizes efficient decoupling and flexible motion of three degrees of freedom, has the advantages of light weight and whole-circle rotation, wherein the decoupling of the pitching, yawing and rotating motions is realized by the separate pointing motion branch (pitching, yawing) and the intermediate rotating branch, and the closed-loop control of the three groups of driving ropes. Each degree of freedom is controlled by an independent driving wheel and a driving rope, the motion coupling is reduced, and the kinematic model is simplified. The pair of closed-loop driving ropes (such as S1 / S2 driving pitching and S3 driving rotating) realize accurate angle adjustment by differential tensioning / relaxing, avoiding the cumulative error of the traditional serial mechanism. The rope driving provides flexibility, is suitable for human-machine cooperation or precision operation, the guide wheel assembly optimizes the rope path, and reduces the friction loss.

[0069] Compared with the traditional driving modes such as gears and connecting rods, the driving rope assembly has high transmission efficiency and low friction loss, avoids the manufacturing and assembly difficulties brought by the complex mechanical transmission structure, reduces the cost, improves the reliability and maintainability of the system, and is convenient for realizing accurate motion control and real-time adjustment to adapt to different work tasks and requirements.

[0070] Specifically, referring to Figure 2 As shown in the figure, the connecting rod assembly includes a first connecting rod L1, a second connecting rod L2, a third connecting rod L3 and a fourth connecting rod L4, wherein:

[0071] The first connecting rod L1 is connected with the second connecting rod L2 through a third rotating pair R3; the second connecting rod L2 is connected with the third connecting rod L3 through a fourth rotating pair R4; the third connecting rod L3 and the fourth connecting rod L4 are connected through a fifth rotating pair R5;

[0072] The first connecting rod L1 is fixedly connected with the yawing driving wheel P2 through a transmission shaft, the third connecting rod L3 is fixedly connected with the moving platform 4, and the fourth connecting rod L4 is fixedly connected with the pitching driving wheel P1 through a transmission shaft;

[0073] The fourth rotational pair R4 and the fifth rotational pair R5 are both located on the third connecting rod L3, and the fourth rotational pair R4 and the fifth rotational pair R5 have an included angle therebetween.

[0074] Specifically, in the embodiment, the first connecting rod L1 obtains power from the deflection driving wheel P2, transmits the power to the second connecting rod L2 through the third rotational pair R3, transmits the power to the third connecting rod L3 through the fourth rotational pair R4, and finally transmits the power to the moving platform 4 and the pitch driving wheel P1 through the fifth rotational pair R5. In this way, the multi-connecting rod structure can separate the deflection and the pitch movement, and reduce coupling. The included angle between the rotational pairs can help to decompose the movement direction, for example, to independently control the deflection and the pitch. The four-connecting rod mechanism (L1-L4) can amplify the small angle change of the driving wheel into a large range of movement of the moving platform through the series connection of the rotational pairs, and improve the joint flexibility; the connecting rod assembly forms a folding structure through the multiple rotational pairs (R3-R5), and can be retracted in the non-working state to reduce the space occupation; when unfolded, the movement range is expanded through the included angle design (R4 and R5); the included angle of the fourth rotational pair R4 and the fifth rotational pair R5 (such as orthogonal or a specific angle) can further separate the transmission paths of the deflection and the pitch movement, and reduce the movement interference.

[0075] Therefore, the four-connecting rod assembly realizes the physical decoupling of the deflection and the pitch movement through the series connection of multiple rotational pairs + the included angle design, combines the force efficiency of the rigid transmission and the flexibility of the rope driving, but needs to balance the multi-joint error accumulation and the dynamic performance limitation. Further combined with high-precision manufacturing, lightweight materials and intelligent control algorithms, the practicality in the precise operation scene can be significantly improved.

[0076] Specifically, referring to FIGS. 1 to 3, Figure 1 , 2 As shown in FIGS. 1 to 3, the intermediate rotary branch 3 includes a base flange c, a rotary driving wheel d, a rotary connecting flange e and a universal hinge U, wherein:

[0077] The universal hinge U is composed of a universal hinge lower fork f, a universal hinge upper fork h and a universal hinge center block g. The universal hinge with this structure has good rigidity and stability, can effectively reduce deformation and shaking in the process of transmitting movement and force, ensures the attitude stability of the moving platform 4 in the movement process, avoids the problems of movement precision decline or shaking of the moving platform 4 caused by the unstable structure of the universal hinge itself, and thus improves the stability and movement precision of the whole system in the running process.

[0078] The base flange c is fixedly connected with the static platform base 1, and provides a stable support base for the entire intermediate rotary branch 3. The base flange c is connected with the rotary driving wheel d through the sixth rotary pair R6. The rotary driving wheel d is fixedly connected with the universal hinge lower fork f, so that the rotary driving wheel d can rotate smoothly around the whole circle, and further drive the universal hinge lower fork f to rotate correspondingly. The entire intermediate rotary branch 3 has a certain load capacity, and can bear the inertial force, gravity and other forces generated by the dynamic platform 4 and various loads carried thereon during movement, thereby ensuring the normal operation of the system under load.

[0079] The universal hinge upper fork h penetrates the center of the dynamic platform 4 and is connected with the dynamic platform 4 through the seventh rotary pair R7. Such a structure enables the dynamic platform 4 to change its posture and direction flexibly under the action of the universal hinge U according to actual needs, and realize multi-degree-of-freedom movement. The connection and transmission between the components of the entire intermediate rotary branch 3 during movement are relatively coherent, effectively ensuring the flexibility and coherence of movement, and can adapt to complex and variable working scenes and movement requirements.

[0080] Therefore, the base flange c, the rotary driving wheel d, the rotary connection flange e and the universal hinge U and other components are not only compact and reasonable in layout, but also connected between components through rotary pairs and other means, which not only meets the requirements of movement transmission, but also saves space to some extent. The entire intermediate rotary branch 3 can realize complex rotary movement and posture adjustment function in limited space, which is conducive to the miniaturization and lightweight design of the overall equipment, and improves the space utilization rate.

[0081] Specifically, as shown in Figure 1 、 2 , the first rotary pair R1, the second rotary pair R2, the third rotary pair R3, the fourth rotary pair R4, the fifth rotary pair R5, the sixth rotary pair R6 and the seventh rotary pair R7 converge at a point, and the convergence center coincides with the rotation center of the universal hinge U. The first rotary pair R1 and the second rotary pair R2 are both horizontally fixed.

[0082] Therefore, such a layout greatly improves the precision of the entire mechanism movement. During movement, the rotary actions of each rotary pair can be performed around the same center, avoiding the accumulation of movement errors caused by the relative position deviation between different rotary pairs, so that the movement coordination between components is more accurate and coordinated, and complex and precise movement trajectories and posture changes can be realized, meeting the needs of high-precision operation or movement control.

[0083] Both the first revolute joint R1 and the second revolute joint R2 maintain a fixed horizontal direction, providing a stable horizontal reference for the movement of the entire mechanism. During operation, these two horizontal revolute joints ensure the deterministic and consistent movement or posture adjustment of the connected components in the horizontal direction, helping to maintain the coordination of the entire mechanism's movement in the horizontal plane and avoiding problems such as mechanism vibration and deviation caused by uncontrolled or uncoordinated horizontal movement, further improving the smoothness and accuracy of the mechanism's movement.

[0084] The confluence structure of the rotating joint components allows forces from all directions to be concentrated at the confluence center, and then effectively transmitted and dispersed through the universal joint U. This force transmission method enables the various rotating joints to share the load when the entire mechanism is under load, avoiding problems such as wear, deformation, or damage caused by excessive force on a single rotating joint, thereby improving the load capacity of the mechanism and enabling it to adapt to working scenarios with larger loads.

[0085] Due to the convergence of the rotating joints and the reasonable arrangement of the universal joints, the mechanism exhibits good stability during movement. The mutual constraints and synergistic effects between the various rotating joints enable the mechanism to quickly adjust its posture and return to a stable working state when subjected to external disturbances or load changes. This reduces the adverse effects of vibration and swaying caused by instability, ensuring the reliability and stability of the mechanism during long-term operation.

[0086] Specifically, please refer to Figure 1 , 2 As shown, the guide wheel assembly includes a first guide wheel group Z1, a second guide wheel group Z2, a third guide wheel group Z3, and a fourth guide wheel group Z4, wherein:

[0087] The first guide wheel group Z1 has a fifth pulley P5 and a ninth pulley P9, as well as a sixth pulley P6 and a tenth pulley P10 symmetrically arranged at both ends.

[0088] The two ends of the second guide wheel group Z2 are symmetrically arranged with the thirteenth pulley P13 and the fifteenth pulley P15, as well as the fourteenth pulley P14 and the sixteenth pulley P16.

[0089] The third guide wheel group Z3 has the seventh pulley P7 and the eleventh pulley P11, as well as the eighth pulley P8 and the twelfth pulley P12 symmetrically arranged at both ends.

[0090] The fourth guide wheel group Z4 has a third pulley P3 and a fourth pulley P4 symmetrically arranged at both ends, and the fourth guide wheel group Z4 is connected to the static platform base 1 through the guide wheel base.

[0091] Specifically, this guide wheel assembly, through the symmetrical arrangement of multiple guide wheel groups and pulleys, effectively guides and constrains the rope, causing it to move along a predetermined path. The symmetrically arranged pulleys ensure uniform force on the rope as it enters and exits the guide wheel assembly, reducing problems such as offset and vibration caused by uneven force distribution, thereby improving the stability of the entire transmission system. Pulleys on different guide wheel groups can guide the rope from different directions, allowing the rope to flexibly change its direction of motion in various directions, achieving complex motion transmission and conversion, and meeting the requirements for motion flexibility in different application scenarios.

[0092] The fourth guide wheel assembly Z4 is connected to the static platform base 1 through the guide wheel base, providing a stable support foundation for the entire guide wheel assembly. This allows the guide wheel assembly to maintain a relatively stationary position during operation, further enhancing the stable guidance of the rope and avoiding problems such as decreased transmission accuracy or disordered transmission medium caused by the shaking of the guide wheel assembly itself.

[0093] In addition, the symmetrical arrangement of the guide wheel assembly is compact and reasonable in terms of spatial layout. The various guide wheel groups and pulleys are distributed in a relatively concentrated area, making full use of the limited space and reducing the overall volume occupied by the guide wheel assembly. This is conducive to the miniaturization of the entire transmission system or equipment, and is especially suitable for application scenarios with strict requirements on space dimensions.

[0094] Specifically, please refer to Figure 1 , 2 As shown, the static platform base 1 has an inverted U-shaped structure, which inherently possesses high stability. The inverted U-shaped structure has a central crossbeam running through the first beam H1 and the second beam H2, providing ample space for the installation of the guide wheel assembly without occupying excessive additional space. In this embodiment, the first guide wheel assembly Z1 and the second guide wheel assembly Z2 are installed on the first beam H1, and the third guide wheel assembly Z3 and the fourth guide wheel assembly Z4 are installed on the second beam H2. This not only further enhances the rigidity and strength of the static platform base 1, enabling it to withstand larger loads and various external forces, but also provides a stable support foundation for the guide wheel assembly and other related components installed on it. This reduces problems such as component position displacement or malfunctions caused by deformation or shaking of the static platform base 1, improving the reliability of the entire system during operation.

[0095] The first crossbeam H1 and the second crossbeam H2 are respectively equipped with guide wheel sets. This layout allows the weight and working load of the guide wheel sets to be evenly distributed to all parts of the base, avoiding excessive local stress, further enhancing the load-bearing capacity and stability of the entire structure, and helping to extend the service life of the equipment.

[0096] Thus, by installing the guide wheel set on the first and second cross beams H1 and H2 respectively, the movement component or transmission medium can be effectively guided and constrained to move along the predetermined path. The cooperation between different guide wheel sets can realize complex movement trajectories and movement direction conversion, ensuring the stability and accuracy of the movement component or transmission medium during movement, and improving the movement performance and working efficiency of the entire system. Since the guide wheel set is installed on the relatively fixed cross beam, its position and posture are relatively stable, which can provide consistent guidance for the movement component or transmission medium, avoiding movement errors or movement incoordination caused by unstable guide wheel set position, making the movement of the entire system more coordinated and smooth, which is beneficial to improve the quality and production efficiency of the product.

[0097] Specifically, please refer to Figure 1 、 2 , 3, 4, the starting end of the two first driving ropes S1 is fixed on the knot hole of the pitch driving wheel P1, ensuring the reliable connection between the first driving rope S1 and the pitch driving wheel P1, effectively converting the rotary motion of the pitch driving wheel P1 into the linear motion of the first driving rope S1, providing an accurate starting point and motion source for the entire transmission process. The other end of the two first driving ropes S1 respectively passes through the first and second wire holes K1 and K2 of the static platform base 1, and plays a guiding and limiting role for the first driving rope S1, so that the first driving rope S1 can move along the predetermined path, avoiding random swinging and winding of the first driving rope S1 during movement, ensuring the accuracy of the movement of the first driving rope S1, and also reducing the transmission error and failure risk caused by unstable path of the first driving rope S1. The two first driving ropes S1 pass through the sixth and tenth pulleys P6 and P10 from below, then pass through the fifth and ninth pulleys P5 and P9 from above respectively, and pass through the first guide wheel set Z1, and the ends of the two first driving ropes S1 extend downward in front of and behind the output end of the first driving member in a symmetrical manner, further accurately guiding and adjusting the movement of the first driving rope S1. The pulley can change the movement direction of the first driving rope S1, and under the action of the pulley and the guide wheel set, the first driving rope S1 can maintain a stable tension state, ensuring its smoothness and accuracy during movement, so that the first driving rope S1 can accurately transmit power to the output end of the first driving member, improving the movement accuracy and reliability of the entire transmission system.

[0098] Thus, the first driving rope S1 is transmitted from the pitch driving wheel P1 to the output end of the first driving member through a plurality of pulleys and guide wheel groups, and this transmission mode can effectively transmit and distribute the driving force. In the transmission process, the pulleys play a role in supporting and changing the direction of the force, so that the driving force can be accurately transmitted to the target position along the predetermined path, reducing the loss and waste of the force and improving the transmission efficiency.

[0099] In addition, the first driving rope S1 passes through the wire guide hole of the static platform base 1 and the winding between each pulley and guide wheel group, fully utilizing the space, so that the transmission path of the first driving rope S1 is more compact and simple, reducing the redundant length and unnecessary bending of the first driving rope S1 in space, avoiding the problems of space waste and interference caused by the excessive length or unreasonable arrangement of the first driving rope S1, and facilitating the miniaturization and compact design of the entire device, improving the space utilization.

[0100] Specifically, as shown in Figure 1 、 2 , 3, 4, the starting ends of the two second driving ropes S2 are fixed on the knot holes of the deflection driving wheel P2, and the other ends pass through the third wire guide hole K3 and the fourth wire guide hole K4 on the static platform base 1, pass under the fourteenth pulley P14 and the sixteenth pulley P16, pass over the thirteenth pulley P13 and the fifteenth pulley P15, and pass through the second guide wheel group Z2; the ends of the two second driving ropes S2 extend downward in a front-rear symmetrical manner to be connected with the output end of the second driving member.

[0101] In the embodiment of the application, the two second driving ropes S2 are transmitted from the deflection driving wheel P2 to the output end of the second driving member through a plurality of pulleys and guide wheel groups, and this transmission mode can effectively transmit and distribute the driving force. In the transmission process, the pulleys play a role in supporting and changing the direction of the force, so that the driving force can be accurately transmitted to the target position along the predetermined path, reducing the loss and waste of the force and improving the transmission efficiency. The front-rear symmetrical arrangement of the two second driving ropes S2 makes the forces borne by the two second driving ropes S2 relatively uniform in the transmission process, avoiding the problems of accelerated wear of the driving rope or unstable transmission caused by uneven force, further improving the reliability and durability of the transmission system, and also ensuring that the force transmission is more stable and accurate, which is conducive to improving the operation efficiency and performance of the entire system.

[0102] Specifically, as shown in Figure 1 、 2, 3, 4, the starting end of the two third driving ropes S3 is wound and fixed on the knot hole of the rotary driving wheel d, the other end passes through the third pulley P3 and the fourth pulley P4 on the fourth guide wheel set Z4, then passes through the fifth guide hole K5 and the sixth guide hole K6 on the static platform base 1 respectively, and then passes through the eighth pulley P8 and the twelfth pulley P12 from below respectively, passes through the seventh pulley P7 and the eleventh pulley P11 from above respectively and passes through the third guide wheel set Z3; the tail end of the two third driving ropes S3 extends downward in a front-rear symmetrical manner to be connected with the output end of the third driving member.

[0103] The arrangement and connection mode of the third driving rope S3 enable the third driving rope S3 to be well integrated with and cooperate with other components such as the rotary driving wheel, the static platform base 1, the pulley, the guide wheel set and the third driving member, etc. An organic whole is formed between the components through the third driving rope S3, the cooperative work and motion transmission between the components are realized, and the integration and reliability of the whole system are improved.

[0104] The transmission process of the third driving rope S3 is coordinated with the motion control of the whole system, the motion speed and position of the third driving rope S3 can be accurately adjusted through the rotation control of the rotary driving wheel, and then the accurate control of the output end of the third driving member is realized, so that the whole system can stably and reliably run according to the predetermined working requirements and motion law, and the requirements of the system motion accuracy and coordination in different application scenarios are met.

[0105] Specifically, please refer to Figure 1 As shown in the figure, the universal hinge lower fork f and the universal hinge upper fork h are provided with through holes along the long rod direction, so that the cable can be arranged along the hinge axis, and the excessive bending or winding of the cable during the motion is avoided, the universal hinge center block g is provided with a through hole and is suitable for passing through the cable, and the through hole of the universal hinge center block g allows the cable to move freely without being affected by the joint rotation. In this way, the cable can bend with the motion of the universal hinge U, but will not be twisted, prolonging the service life.

[0106] Although the present application is disclosed as above, the protection scope of the present application is not limited to this. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application, and these changes and modifications will fall within the protection scope of the present application.

Claims

1. A three degree of freedom decoupled wrist characterized by, The utility model relates to a kind of decoupling wrist, including: Static platform base; Dynamic platform; Pointing movement branch, be equipped in the upper of the static platform base, the pointing movement branch includes pitch support seat, deflection support seat, pitch drive wheel, deflection drive wheel and connecting rod assembly, the pitch support seat, the deflection support seat are fixed with the static platform base;The pitch drive wheel is connected with the pitch support seat by first rotary pair, and the deflection drive wheel is connected with the deflection support seat by second rotary pair; The connecting rod assembly includes first connecting rod, second connecting rod, third connecting rod and fourth connecting rod, wherein: The first connecting rod is connected with the second connecting rod by third rotary pair;The second connecting rod is connected with the third connecting rod by fourth rotary pair;The third connecting rod and the fourth connecting rod are connected by fifth rotary pair; The first connecting rod is fixed with the deflection drive wheel by transmission shaft, the third connecting rod is fixed with the dynamic platform, and the fourth connecting rod is fixed with the pitch drive wheel by transmission shaft; The fourth rotary pair and the fifth rotary pair are all located on the third connecting rod, and the fourth rotary pair and the fifth rotary pair have an included angle between them; Intermediate rotary branch, installed between the static platform base and the dynamic platform; Guide wheel assembly, installed on the static platform base; Drive rope assembly, including first drive rope, second drive rope and third drive rope of a pair of closed loop drive same joint, the drive rope assembly is suitable for winding connection between the guide wheel assembly, the pointing movement branch and the intermediate rotary branch; The decoupling wrist is suitable for rotating and whole rotation in three degrees of freedom movement direction by the drive rope assembly.

2. The three degree-of-freedom decoupled wrist of claim 1, wherein, The intermediate rotary branch includes base flange, rotary drive wheel, rotary connection flange and universal hinge, wherein: The universal hinge is composed of universal hinge lower fork, universal hinge upper fork and universal hinge center block; The base flange is fixed with the static platform base, and the base flange is connected with the rotary drive wheel by sixth rotary pair, and the rotary drive wheel is fixed with the universal hinge lower fork; The direction of the sixth rotary pair is perpendicular to the static platform base, and the sixth rotary pair is suitable for whole rotation; The universal hinge upper fork passes through the center of the dynamic platform and is connected with the dynamic platform by seventh rotary pair.

3. The three degree-of-freedom decoupled wrist of claim 2, wherein, The first rotary pair, the second rotary pair, the third rotary pair, the fourth rotary pair, the fifth rotary pair, the sixth rotary pair and the seventh rotary pair converge at a point, and the convergence center coincides with the rotation center of the universal hinge;The first rotary pair and the second rotary pair remain horizontal fixed direction.

4. The three degree-of-freedom decoupled wrist of claim 3, wherein, The guide wheel assembly includes first guide wheel group, second guide wheel group, third guide wheel group and fourth guide wheel group; Two ends of the first guide wheel group are respectively arranged with fifth pulley and ninth pulley and sixth pulley and tenth pulley symmetrically; Two ends of the second guide wheel group are respectively arranged with thirteenth pulley and fifteenth pulley and fourteenth pulley and sixteenth pulley symmetrically; Two ends of the third guide wheel group are respectively arranged with seventh pulley and eleventh pulley and eighth pulley and twelfth pulley symmetrically; The third pulley and the fourth pulley are symmetrically arranged at the two ends of the fourth guide wheel group respectively, and the fourth guide wheel group is connected to the static platform base through a guide wheel base.

5. The three degree-of-freedom decoupled wrist of claim 4, wherein, The static platform base is in an inverted U-shaped structure, the middle of the inverted U-shaped structure transversely crosses the first cross beam and the second cross beam, the first cross beam is provided with the first guide wheel group and the second guide wheel group, and the second cross beam is provided with the third guide wheel group and the fourth guide wheel group.

6. The three degree-of-freedom decoupled wrist of claim 4, wherein, The starting ends of the two first driving ropes are fixed to the knot holes of the pitching driving wheel, the other ends pass through the first wire hole and the second wire hole of the static platform base downwards, pass through the lower sides of the sixth pulley and the tenth pulley, pass through the upper sides of the fifth pulley and the ninth pulley, and pass through the first guide wheel group; the ending ends of the two first driving ropes extend downwards to the output ends of the first driving member in a front-rear symmetric manner.

7. The three degree-of-freedom decoupled wrist of claim 4, wherein, The starting ends of the two second driving ropes are fixed to the knot holes of the deflection driving wheel, the other ends pass through the third wire hole and the fourth wire hole of the static platform base, pass through the lower sides of the fourteenth pulley and the sixteenth pulley, pass through the upper sides of the thirteenth pulley and the fifteenth pulley, and pass through the second guide wheel group; the ending ends of the two second driving ropes extend downwards to the output ends of the second driving member in a front-rear symmetric manner.

8. The three degree-of-freedom decoupled wrist of claim 5, wherein, The starting ends of the two third driving ropes are fixed to the knot holes of the rotation driving wheel, the other ends pass through the third pulley and the fourth pulley of the fourth guide wheel group, then pass through the fifth wire hole and the sixth wire hole of the static platform base, pass through the lower sides of the eighth pulley and the twelfth pulley, pass through the upper sides of the seventh pulley and the eleventh pulley, and pass through the third guide wheel group; the ending ends of the two third driving ropes extend downwards to the output ends of the third driving member in a front-rear symmetric manner.

9. The three degree-of-freedom decoupled wrist of claim 3, wherein, The lower fork and the upper fork of the universal hinge are provided with through holes in the long rod direction, and the central block of the universal hinge is provided with a through hole and is suitable for passing through a cable.

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