CN110561493A

CN110561493A - Anthropomorphic mechanical arm

Info

Publication number: CN110561493A
Application number: CN201910734438.5A
Authority: CN
Inventors: 徐文福; 陈永厅; 韩亮; 郑宁靖
Original assignee: Shenzhen Graduate School Harbin Institute of Technology
Current assignee: Shenzhen Graduate School Harbin Institute of Technology
Priority date: 2019-08-09
Filing date: 2019-08-09
Publication date: 2019-12-13
Anticipated expiration: 2039-08-09
Also published as: CN110561493B

Abstract

The invention discloses a humanoid mechanical arm, and belongs to the technical field of robots. The anthropomorphic mechanical arm comprises a plurality of vertical joints, a transverse joint is arranged between every two adjacent vertical joints, the vertical joints are coaxially arranged, and the axis of the transverse joint is mutually perpendicular to the axial direction of the vertical joints. The anthropomorphic mechanical arm has enough arm length, large motion space and light weight.

Description

Anthropomorphic mechanical arm

Technical Field

The invention relates to the technical field of robots, in particular to a humanoid mechanical arm.

Background

In the development of the robot, various robots are developed and applied, wherein the mobile quadruped and hexapod robot has super-strong environmental adaptability, thereby attracting the research of universities and research institutes, and in addition, the wheel type mobile platform is also widely applied. In order to realize object grabbing and remote unmanned operation of a foot type or wheel type mobile platform, a mechanical arm which can be used for operation needs to be equipped. However, existing industrial robots are too heavy to fit on mobile platforms.

At present, the cooperative mechanical arm has better performance and lighter weight, but the weight of the main cooperative mechanical arm is about 20kg, and the weight of the main cooperative mechanical arm is 11kg to 15kg, but the arm length of the cooperative mechanical arm is too short, and the operation space is smaller.

Disclosure of Invention

In order to overcome the defects in the prior art, the embodiment of the invention provides the anthropomorphic mechanical arm which is long in arm length, large in operation space and light in weight.

The embodiment of the invention adopts the following technical scheme for solving the technical problems: the anthropomorphic mechanical arm comprises a plurality of vertical joints, a transverse joint is arranged between every two adjacent vertical joints, the vertical joints are coaxially arranged, and the axes of the transverse joints are perpendicular to the axes of the vertical joints.

As a further improvement of the technical scheme, the device comprises four vertical joints and three transverse joints.

As a further improvement of the technical scheme, the vertical joint is connected with the transverse joint through a joint connecting rod, the joint connecting rod is arranged in a hollow mode, and the transverse joint is located inside the joint connecting rod.

as a further improvement of the above technical solution, the joint connecting rod includes a curved surface turning part, the curved surface turning part is in a shape of "7", one end of the curved surface turning part is coaxial with the vertical joint, and the other end of the curved surface turning part is coaxial with the horizontal joint.

As a further improvement of the above technical solution, the joint connecting rod further includes a vertical connecting portion, and both ends of the vertical connecting portion are respectively coaxially connected with the curved surface turning portion and the vertical joint.

As a further improvement of the technical scheme, the vertical connecting part and the vertical joint are sealed through a rubber ring.

As a further improvement of the above technical solution, the joint further includes a driver, the driver is disposed in the vertical connecting portion at the two ends of the vertical joint, the driver at one end of the vertical joint is electrically connected to the vertical joint, and the driver at the other end of the vertical joint is electrically connected to the adjacent horizontal joint.

As a further improvement of the above technical scheme, the horizontal joint with vertical joint is the modularization joint, the modularization joint includes shell, encoder mounting, the encoder mounting includes outer lane, inner circle and a plurality of spoke, and is a plurality of spoke circumference evenly set up in the outer lane with between the inner circle, the both ends of spoke respectively with the outer lane and the inner circle is connected, a plurality of radial screw holes that set up are seted up to the outer lane, the outer lane passes through the screw hole with the shell spiro union, fastening connection has absolute encoder on the terminal surface of encoder mounting.

As a further improvement of the above technical scheme, the modularization joint still includes the spool, the spool includes cavity central siphon and connecting piece, the connecting piece is located the one end of cavity central siphon, and to the radial direction of cavity central siphon extends, the connecting piece with encoder mounting fastening connection.

As a further improvement of the above technical solution, the modular joint further includes a motor shaft and a harmonic reducer, the harmonic reducer includes a wave generator, the wave generator and the motor shaft are positioned by a shaft shoulder, and in the axial direction, the wave generator and the motor shaft are fastened and connected by a screw, and a wire passing hole is formed in the center of the wave generator.

The invention has the beneficial effects that:

The anthropomorphic mechanical arm comprises a plurality of vertical joints, a transverse joint is arranged between every two adjacent vertical joints, the axes of the vertical joints are perpendicular to those of the transverse joints, a vertically and horizontally staggered structure is adopted, the arm length of the mechanical arm is ensured, meanwhile, the influence of the weight on the vertical joints is small, the torque requirement of the vertical joints is low, and the overall structure can be smaller and lighter.

Drawings

The invention is further illustrated with reference to the following figures and examples.

FIG. 1 is a schematic view of the overall structure of one embodiment of the anthropomorphic robotic arm of the present invention;

FIG. 2 is a schematic structural view of an embodiment of a joint connecting structure of the anthropomorphic mechanical arm of the present invention;

FIG. 3 is a cross-sectional view of a joint of the anthropomorphic robotic arm of the present invention;

FIG. 4 is a schematic structural diagram of an embodiment of an encoder fixture of the present invention;

Fig. 5 is a schematic structural view of one embodiment of the conduit of the present invention.

Detailed Description

The conception, the specific structure and the technical effects of the present invention will be clearly and completely described in conjunction with the embodiments and the accompanying drawings to fully understand the objects, the schemes and the effects of the present invention. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

It should be noted that, unless otherwise specified, when a feature is referred to as being "fixed" or "connected" to another feature, it may be directly fixed or connected to the other feature or indirectly fixed or connected to the other feature. Furthermore, the descriptions of up, down, left, right, front, rear, etc. used in the present invention are only relative to the positional relationship of the respective components of the present invention with respect to each other in the drawings.

Furthermore, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any combination of one or more of the associated listed items.

Referring to fig. 1 and 2, an embodiment of the invention provides a anthropomorphic mechanical arm, which comprises a plurality of vertical joints 1 and a plurality of transverse joints 2, wherein the vertical joints 1 and the transverse joints 2 are arranged in a sequentially staggered manner, that is, the transverse joints 2 are arranged between adjacent vertical joints 1, the vertical joints 1 are coaxially arranged to ensure the coaxiality of the whole mechanical arm, and the axial direction of the transverse joints 2 is perpendicular to the axial direction of the vertical joints 1. The anthropomorphic mechanical arm provided by the embodiment of the invention adopts a horizontally and vertically staggered arrangement structure, the whole arm length can be ensured, a larger operation space can be provided, and meanwhile, the influence of gravity on the vertical joint 1 is small, so that the requirement on torque is small, and the structure of the joint is smaller and lighter.

In a preferred embodiment, the anthropomorphic robot arm comprises four vertical joints 1 and three transverse joints 2, wherein the four vertical joints 1 and the three transverse joints 2 form 7 degrees of freedom to ensure good flexibility, in the embodiment, as shown in fig. 2, from the top to bottom direction in fig. 2, a first vertical joint 1 and a first transverse joint 2 form a shoulder joint of the anthropomorphic robot arm to simulate the movement of a shoulder of a human body, a second vertical joint 1 and a second transverse joint 2 form an elbow joint of the anthropomorphic robot arm to default the movement of the elbow of the human body, a third vertical joint 1, a third transverse joint 2 and a fourth vertical joint 1 form a wrist joint of the anthropomorphic robot arm to default the movement of the wrist of the human body, and three degrees of freedom including rolling, pitching and yawing can be realized through the two vertical joints 1 and the one transverse joint 2.

With continued reference to fig. 1 and 2, the joints are connected by joint links to realize linkage between the joints.

In one embodiment, the joint connecting rod comprises a curved surface turning part 30, the curved surface turning part 30 is used for butt joint of a vertical joint 1 and a transverse joint 2, the curved surface turning part 30 is in a 7 shape, one end of the curved surface turning part 30 is connected with the vertical joint 1, the other end of the curved surface turning part 30 is connected with the adjacent transverse joint 2, and through a curved surface structure in the 7 shape, connection between two joints in different directions is achieved, so that linkage between the two joints is achieved.

The curved surface turning part 30 is of a hollow structure, one end of the curved surface turning part connected with the transverse joint 2 is sleeved on the outer surface of the transverse joint 2, and the whole transverse joint 2 is coated inside the curved surface turning part 30 through a pair of mutually matched curved surface turning parts to seal the transverse joint 2 and ensure that devices inside the transverse joint 2 are in a good working environment.

Preferably, two curved surface turning parts 30 which are matched with each other can rotate relatively, when being installed, the two curved surface turning parts 30 are respectively fastened and connected with the corresponding transverse joint 2, wherein one curved surface turning part 30 is fastened and connected with one end of the transverse joint 2 through a plurality of screws arranged along the axial direction of the transverse joint 2, the other curved surface turning part 30 is fastened and connected with the other end of the transverse joint 2 through a plurality of screws arranged along the axial direction of the transverse joint 2, the position of the joint of the transverse joint 2 and one curved surface turning part 30 is fixed, and the joint of the transverse joint 2 and the other curved surface turning part 30 can rotate.

Further, the joint connecting rod further comprises a vertical connecting portion 31, one end of the vertical connecting portion 31 is connected with the curved surface turning portion 30, the other end of the vertical connecting portion 31 is connected with the adjacent vertical joint 1, specifically, the end portion of the vertical connecting portion 31 is connected with the end portion of the vertical joint 1, the inner diameter of the vertical connecting portion 31 is equal to or slightly larger than the outer diameter of the end portion of the vertical joint 1, so that the end portion of the vertical connecting portion 31 is sleeved on the end portion of the vertical joint 1, and then the vertical connecting portion 31 and the vertical joint 1 are fastened together through screws in the radial direction relative to the vertical joint 1.

Preferably, the rubber ring 4 is sleeved at the joint of the vertical connecting part 31 and the vertical joint 1, and the joint of the vertical connecting part and the vertical joint is sealed by the rubber ring 4.

Preferably, a sealing shell 10 is sleeved outside the vertical joint 1, and two ends of the sealing shell 10 are sealed by the rubber ring 4. Therefore, a sealed space is formed by the joint connecting rod, the rubber ring 4 and the sealing shell 10, the vertical joint 1 and the transverse joint 2 which are positioned in the sealed space can be ensured to be in a sealed working environment, and good operation of parts is ensured. Preferably, the sealing case 10 is formed by 3D printing.

The arm length of this anthropomorphic robot arm has been increased in vertical connecting portion 31's setting, and simultaneously, vertical connecting portion 31 also sets up in cavity, at the both ends department of vertical joint 1, be provided with driver 5 in the vertical connecting portion 31, wherein, the driver 5 of vertical joint 1 one end is used for driving the operation of this vertical joint 1, the driver 5 of the vertical joint 1 other end is used for driving the operation of horizontal joint 2 adjacent with it, each joint and the driver of whole anthropomorphic robot set up according to this, thereby the length of horizontal joint 2 has been reduced, the holistic arm length has been increased, so that reduce holistic weight. The driver 5 is mainly used for driving the motor and communicating with the shell control platform, in this embodiment, the driver 5 preferably adopts EtherCAT communication, is compatible with Ethernet, and can realize remote and ultra-remote control.

according to the anthropomorphic mechanical arm disclosed by the embodiment of the invention, the vertical joint 1 and the transverse joint 2 adopt modular joints, so that the manufacturing cost can be reduced, and the research and development period can be shortened.

Fig. 3 shows a schematic cross-sectional view of a joint at a shoulder joint. The modular joint comprises a conduit, a housing 101, a motor shaft 102, a rotor 1030, a stator 1031, an output adaptor 104 and a harmonic reducer 105.

the spool includes cavity central siphon 1000, the inside cavity of cavity central siphon 1000, in order to be used for the articulated line of walking, motor shaft 102 is located on the cavity central siphon 1000, rotor 1030 tight sleeve is located on motor shaft 102, it rotates with motor shaft 102 synchronous when the motion, stator 1031 is established the cover and is located on rotor 1030, stator 1031's outer lane and shell 101 fastening connection, during the motion, stator 1031 is static, rotor 1030 rotates, thereby drive motor shaft 102 and rotate, cavity central siphon 1000 and shell 101 fastening connection, make the spool static for shell 101, the line of walking in the cavity central siphon 1000 is not influenced by motor shaft 102's operation, the reliability of power supply and model has been improved.

The harmonic reducer 105 comprises a wave generator 1050, the wave generator 1050 is in an L-shaped structure, one end of the wave generator 1050 is embedded between the motor shaft 102 and the hollow shaft tube 1000 and is attached to the inner wall of the motor shaft 102, the other end of the wave generator 1050 is attached to the end face of the motor shaft 102, the motor shaft 102 is matched with the wave generator 1050 through a shaft shoulder to achieve positioning of the wave generator 1050, the wave generator 1050 is fastened with the motor shaft 102 through a plurality of axial screws to ensure synchronous movement of the wave generator and the motor shaft, and meanwhile, a central hole is formed in the center of the wave generator 1050 to. In the embodiment of the invention, the problem that the harmonic reducer cannot be hollow wired is solved by improving the wave generator 1050, and meanwhile, the weight and the volume of the anthropomorphic mechanical arm can be obviously reduced by utilizing the advantages of light weight and small volume of the harmonic reducer.

In one embodiment, for the modular joint at the shoulder joint and elbow joint, as shown in fig. 3, the harmonic reducer 105 is an integral harmonic reducer, which includes a housing 1051, and the wave generator 1050 can rotate relative to the housing 1051, in this embodiment, the housing 1051 of the harmonic reducer is a part of the joint housing, and the housing 1051 of the harmonic reducer is tightly connected with the housing 101 of the modular joint by axially disposed screws.

The output adaptor 104 is arranged at the end of the modular joint, the output adaptor 104 is fastened and connected with the harmonic reducer 105 through bolts, when the motor shaft 102 rotates, the wave generator 1050 and the output adaptor 104 rotate synchronously, and the output adaptor 104 can be connected with an external component and used for driving the external component to move.

when in work, the modularized joint needs to be arranged with one end as a fixed end. The other end is a rotating end, that is, the end where the output adaptor 104 is located is a rotating end of the modular joint, the other end of the modular joint is a fixed end, the curved surface turning part 30 at one end of the transverse joint 2 is fixedly connected with the output adaptor 104 to rotate synchronously with the rotation of the output adaptor 104, and the curved surface turning part 30 at the other end of the transverse joint is fixedly connected with the fixed end to keep the curved surface turning part 30 at the end still, so that the relative rotation of the two curved surface turning parts 30 is realized, and the two connected joints are driven to move relatively.

The stiff end of modularization joint is provided with encoder mounting 106, refer to fig. 3 and 4, encoder mounting 106 includes outer lane 1060, inner circle 1061 and a plurality of spoke 1062, a plurality of spoke 1062 circumference evenly arranges between outer lane 1060 and inner circle 1061, the both ends of spoke 1062 respectively with outer lane 1060, inner circle 1061 fixed connection, encoder mounting 106 is used for the installation of the other part of encoder and stiff end, adopt the outer lane, the inner circle, the connection structure of a plurality of spokes, under the condition of guaranteeing its intensity, the consumptive material of encoder mounting 106 has been reduced, holistic weight has been reduced.

The outer ring 1060 is fastened and connected with the casing 101, as shown in fig. 4, a plurality of threaded holes 10600 penetrate through the outer ring 1060 in the radial direction, the plurality of threaded holes 10600 are uniformly arranged along the circumferential direction of the outer ring 1060, correspondingly, through holes (not shown) are opened at corresponding positions of the casing 101, and the outer ring 1060 is fastened and connected with the casing 101 through bolts, so that the encoder fixing member 106 is guaranteed to be stationary while working with the casing 101. In this embodiment, in order to reduce the overall weight, the shell 101 of the modular joint needs to be designed to be as thin as possible, so that the threaded hole is difficult to open in the shell 101, the problem that the threaded hole cannot be opened in the shell 101 can be solved by the arrangement of the encoder fixing member 106, and the installation position is provided for other components.

As shown in fig. 4, the spoke 1062 is provided with a mounting post 1063, and the encoder 107 is screwed on the mounting post 1063.

Encoder mounting 106 can also be used for the fixed of spool, it has been mentioned above, when moving, hollow central siphon 1000 needs to remain static to avoid the interior line of walking of hollow central siphon 1000 to receive the influence of joint motion, refer to fig. 5, the spool still includes spliced pole 1001, spliced pole 1001 locates the tip of hollow central siphon 1000, it outwards extends along the radial direction of hollow central siphon 1000, spliced pole 1001 and the spoke 1062 spiro union of encoder mounting 106, thereby be in the same place spool and encoder mounting 106 fastening, be equivalent to spool and shell 101 fastening, thereby guarantee that the spool remains static in whole motion process.

At the wrist joint of the anthropomorphic mechanical arm, the structure of the modular joint is basically the same as that of the modular joint at the shoulder joint and the elbow joint, and the difference is that the harmonic reducer adopts a split type harmonic reducer at the wrist joint, and the harmonic reducer is arranged in the shell 101 and is positioned with the shell 101 through a shaft shoulder.

The anthropomorphic mechanical arm has the advantages that:

1. The whole weight is less than 10kg, the load is 2kg, the weight is light, the robot is suitable for being carried on various mobile platforms, and the robot is particularly suitable for four-footed mobile robots with good flexibility and low load capacity.

2. the design of seven degrees of freedom increases the degree of freedom of mechanical arm motion, and can meet additional optimization targets such as singularity avoidance, obstacle avoidance, performance index optimization and the like besides the appointed pose.

3. The joint fixed end and the output end have the same size, can be installed in a positive and negative mode, and improve the parallelism of the transverse joint and the coaxiality of the vertical joint.

4. The joint connecting rod adopts the hollow design of curved surface, and the joint adopts 3D to print the shell and covers, adopts the rubber circle to seal dustproof between the joint, reduces the collision, and the outward appearance is more graceful simultaneously.

5. the driver adopts EtherCAT communication, is compatible with Ethernet, and can realize remote and ultra-remote control.

While the invention has been described with reference to a preferred embodiment, 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.

Claims

1. The anthropomorphic mechanical arm is characterized by comprising a plurality of vertical joints, wherein a transverse joint is arranged between every two adjacent vertical joints, the vertical joints are coaxially arranged, and the axes of the transverse joints are perpendicular to the axes of the vertical joints.

2. The anthropomorphic robotic arm of claim 1 comprising four of the vertical joints and three of the transverse joints.

3. The anthropomorphic mechanical arm as claimed in claim 1 or 2, characterized in that the vertical joint and the transverse joint are connected by a joint link, the joint link is hollow, and the transverse joint is located inside the joint link.

4. The anthropomorphic mechanical arm as claimed in claim 3, wherein the joint connecting rod comprises a curved surface turning part, the curved surface turning part is in a shape like a Chinese character '7', one end of the curved surface turning part is coaxially arranged with the vertical joint, and the other end of the curved surface turning part is coaxially arranged with the transverse joint.

5. The anthropomorphic mechanical arm of claim 4 wherein the joint linkage further comprises a vertical connecting portion, and two ends of the vertical connecting portion are respectively coaxially connected with the curved surface turning portion and the vertical joint.

6. The anthropomorphic robotic arm of claim 5 wherein the vertical connection and the vertical joint are sealed by a rubber ring.

7. The anthropomorphic mechanical arm of claim 5 further comprising a driver, wherein the driver is disposed in the vertical connecting portion at both ends of the vertical joint, the driver at one end of the vertical joint is electrically connected to the vertical joint, and the driver at the other end of the vertical joint is electrically connected to the adjacent transverse joint.

8. The anthropomorphic mechanical arm as claimed in claim 7, wherein the transverse joint and the vertical joint are modular joints, the modular joints comprise a shell and an encoder fixing piece, the encoder fixing piece comprises an outer ring, an inner ring and a plurality of spokes, the spokes are uniformly arranged between the outer ring and the inner ring in the circumferential direction, two ends of the spokes are respectively connected with the outer ring and the inner ring, the outer ring is provided with a plurality of threaded holes arranged in the radial direction, the outer ring is in threaded connection with the shell through the threaded holes, and an absolute encoder is fixedly connected to the end face of the encoder fixing piece.

9. The anthropomorphic mechanical arm of claim 8 wherein the modular joint further comprises a conduit comprising a hollow shaft tube and a connector disposed at one end of the hollow shaft tube and extending in a radial direction of the hollow shaft tube, the connector being in secure connection with the encoder fixture.

10. The anthropomorphic mechanical arm as claimed in claim 9, wherein the modular joint further comprises a motor shaft and a harmonic reducer, the harmonic reducer comprises a wave generator, the wave generator and the motor shaft are positioned through a shaft shoulder, the wave generator and the motor shaft are fixedly connected through a screw in the axial direction, and a wire passing hole is formed in the center of the wave generator.