CN113103276B - A flexibly driven collaborative robot arm joint module - Google Patents

Abstract

The invention discloses a flexibly-driven joint module of a cooperative mechanical arm, which comprises a driving mechanical arm, a rotating mechanical arm, a connecting shaft, a motor, a first rope and a second rope, wherein the driving mechanical arm is connected with the first rope; the driving mechanical arm is hinged with the rotating mechanical arm through a connecting shaft; the motor is arranged on the driving mechanical arm; the starting end of the first rope and the starting end of the second rope are respectively wound on the output shaft of the motor in opposite directions; the first rope and the second rope are wound through the connecting shaft in opposite directions respectively; the tail end of the first rope and the tail end of the second rope are fixed on the rotating mechanical arm; or the middle part of the first rope and the middle part of the second rope are wound around the rotating mechanical arm, and the tail end of the first rope and the tail end of the second rope are fixed on the driving mechanical arm or the rotating mechanical arm. The flexibly-driven joint module of the cooperative mechanical arm greatly reduces the self weight of the mechanical arm, and the joint is driven by two steel wire ropes together, so that the joint can be stretched and compressed, and the reliability of forward and reverse driving of the joint is ensured.

Description

A flexibly driven collaborative robot arm joint module

technical field

The invention relates to the field of robots, in particular to a flexible-driven collaborative robot arm joint module.

Background technique

The development of collaborative service robots for use in close-to-human environments is currently progressing as robotic technology continues to break through. Whereas traditional industrial robots work safely and autonomously through isolation from human contact, cobots complete tasks independently or sequentially in shared spaces or in close contact with people. As an important branch of modern industrial robots, collaborative robots have attracted much attention since their introduction, and have developed rapidly in recent years. When robots and humans coexist at close range as mentioned above, try to ensure that the force of contact is relaxed, which requires the joints of the robot to have a certain degree of softness, that is, the service robot needs to be light in weight, output torque, and capable of high-precision motion control.

At present, most of the widely used joint modules of manipulators use the combination of servo motor and differential reducer. This combination structure has poor joint compliance and low interaction safety with the environment. Moreover, the load-to-weight ratio of the manipulator is low, and the energy consumption of grabbing loads is large. , low efficiency and very low backdrivability.

Contents of the invention

In order to reduce the weight and moment of inertia of the rotating mechanical arm and improve the load-to-weight ratio and reverse driveability of the mechanical arm, the present invention provides a flexible-driven cooperative robotic arm joint module, and the drive motor is arranged between the rotating mechanical arm In addition, it can effectively reduce the weight of the rotating mechanical arm itself; the driving force is transmitted to the driving joint through the rope transmission device, which can be stretched and compressed, ensuring the reliability of the joint in the forward and reverse directions.

Correspondingly, the present invention provides a flexible-driven collaborative robot arm joint module, including a driving robot arm, a rotating robot arm, a connecting shaft, a motor, a first rope and a second rope;

The driving mechanical arm and the rotating mechanical arm are hinged through a connecting shaft;

The motor is arranged on the driving mechanical arm;

The starting end of the first rope and the starting end of the second rope are respectively wound on the output shaft of the motor in opposite directions,

And the middle part of the first rope and the middle part of the second rope respectively go around the connecting shaft in opposite directions;

The end of the first rope is fixed on the rotating mechanical arm, or the end of the first rope is fixed on the driving mechanical arm passing through the rotating mechanical arm,

The end of the second rope is fixed on the rotating mechanical arm, or the end of the second rope passes through the rotating mechanical arm and is fixed on the driving mechanical arm.

In an optional embodiment, the joint of the rotating mechanical arm further includes a steering pulley; at least one of the steering pulleys is arranged on the rotating mechanical arm; the first rope winds around the rotating mechanical arm based on the steering pulley, The second rope is passed around the rotating mechanical arm based on the diverting pulley.

When the first rope passes through the connecting shaft, several first rope loops are formed, and the first rope between two adjacent first rope loops transitions based on the diverting pulley;

When the second rope winds around the connecting shaft, several second rope loops are formed, and the second rope transitions between two adjacent second rope loops based on the diverting pulley.

In an optional embodiment, the joint module of the flexible-driven collaborative robot arm further includes a wire slot wheel set, and the wire slot wheel set includes several wire slot wheels; Above; any one of the wire groove wheels has several wire grooves, and the first rope and the second rope are respectively fitted in the corresponding wire grooves.

In an optional embodiment, the mechanical arm joint also includes a winding wheel, and the winding wheel is coaxially rotated and fitted on the output shaft of the motor; the starting end of the first rope and the starting end of the second rope are based on the winding wheel It is wound on the output shaft of the motor.

In an optional embodiment, the flexible-driven cooperative robot arm joint module further includes several positioning pulleys, and the several positioning pulleys are respectively arranged at preset positions of the driving mechanical arm; the first rope and the second rope The transitions between the reels and the slots are based on corresponding positioning pulleys, respectively.

In an optional embodiment, the rotation direction of the diverting pulley is parallel to or perpendicular to the rotation direction of the slot wheel set.

In an optional embodiment, the wire groove wheel set includes three wire groove wheels, and any wire groove wheel in the wire groove wheels has two wire grooves.

An optional embodiment further includes several steering pulleys; two steering pulleys are arranged on the rotating mechanical arm, and two steering pulleys are arranged on the driving mechanical arm.

In an optional embodiment, the first rope and the second rope are steel wire ropes.

To sum up, the present invention proposes a flexible-driven collaborative robot arm joint module, which can greatly reduce the weight of the rotating robot arm, reduce the moment of inertia, improve the dynamic performance of the robot arm, have good joint compliance, and have good safety force interaction; the robot arm joint Two steel wire ropes are set to pull the connecting shaft, which can be stretched and compressed to ensure the reliability of the drive in the forward and reverse directions of the joint.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

1 is a schematic diagram of an axial view of a flexible-driven cooperative robotic arm joint module of a three-slot embodiment in an embodiment of the present invention;

Fig. 2 is a schematic diagram of the first rope winding of the flexible-driven cooperative robotic arm joint module of the three-slot embodiment in the embodiment of the present invention;

Fig. 3 is a schematic diagram of the second rope winding of the joint module of the flexible-driven cooperative robotic arm of the embodiment of the three wire grooves in the embodiment of the present invention.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

Specifically, the flexible-driven cooperative robot arm joint module provided by the present invention can be designed as a single wire slot, double wire slots, or expanded into N wire slots as required, as long as the spatial position and quality requirements are met. For ease of understanding, the specific embodiment of the present invention is described by taking a three-wire slot as an example.

Fig. 1 shows a schematic diagram of an axial view of a flexibly driven collaborative robotic arm joint module of a three-slot embodiment in an embodiment of the present invention. Specifically, the flexible-driven collaborative robotic arm joint module of the three-slot embodiment of the present invention includes a driving mechanical arm 1, a rotating mechanical arm 2, a connecting shaft 3, a motor 4, a slotting wheel set 10, a steering pulley 5, and a positioning pulley 6 , the first rope 7, the second rope 8 and the reel 9. The driving manipulator 1 and the rotating manipulator 2 are articulated through the connecting shaft 3, forming the main structure of the joint module of the flexible-driven collaborative manipulator.

Further, the motor 4 is arranged on the driving mechanical arm 1 , which can reduce the dead weight of the rotating mechanical arm 2 to a large extent, and correspondingly, reduce the moment of inertia of the rotating mechanical arm 2 .

Further, the first rope 7 and the second rope 8 are arranged on the output shaft of the motor 4, and the two ropes are jointly driven, which can be stretched and compressed, so as to ensure the reliability of the forward and reverse driving of the joint.

Concretely, the joint module of the collaborative robot arm of the flexible drive also includes a steering pulley 51 and a steering pulley 52, and the several steering pulleys 51 and steering pulleys 52 are arranged on the rotating mechanical arm 2, and the first rope 7 is based on the steering pulley 51 Winding around the rotating mechanical arm 2, the second rope 8 is based on the diverting pulley 52 passing through the rotating mechanical arm 2; by setting the diverting pulley on the rotating mechanical arm, the first rope 7 and the second rope 8 can better guide the motor The driving force is evenly distributed on the rotating mechanical arm 2 .

Further, a diverting pulley 53 and a diverting pulley 54 are also arranged on the driving mechanical arm. When the first rope 7 winds around the connecting shaft, several coils are formed as the first rope loops. Between, the first rope 7 transitions based on the diverting pulley 51 and the diverting pulley 53 . When the second rope 8 passes through the connecting shaft, several coils are formed as second rope loops, and between two adjacent second rope loops, the second rope 8 transitions based on the diverting pulley 52 and the diverting pulley 54 . The position of the diverting pulley 5 is set on the center line of the two adjacent coils, which can ensure the symmetry of the first rope 7 and the second rope 8, so that the first rope 7 and the second rope 8 are on the center line of the motor 4. The movement is smoother under the action of driving force.

Specifically, the joint module of the flexible-driven collaborative robotic arm also includes a three-wire sheave 10, which is coaxially rotatable and mounted on the connecting shaft 3, and can rotate around the connecting shaft 3; the three-wire sheave There are two wire grooves on any wire groove wheel, and the first rope 7 and the second rope 8 are respectively matched in the corresponding wire grooves, which can prevent the ropes from being entangled with each other on the connecting shaft.

Specifically, in order to prevent the starting ends of the first rope 7 and the second rope 8 from being entangled on the output shaft of the motor 4, on the output shaft of the motor 4 coaxially rotate with the reel 9, the starting end of the first rope 7 And the starting end of the second rope 8 is wound on the output shaft of the motor by the winding wheel 9.

In a specific embodiment, the positioning pulley 61 and the positioning pulley 62 are fixedly arranged on the preset position of the driving mechanical arm 1, helping to stabilize the routing position of the first rope 7 and the second rope 8, and can also help the first rope 7 and the second rope The second rope 8 transitions between the reel and the grooved wheel, making the routing of the first rope 7 and the second rope 8 smoother.

Fig. 2 is a schematic diagram of the first rope winding of the joint module of the flexible-driven cooperative robotic arm of the embodiment of the three wire grooves in the embodiment of the present invention. Specifically, in the embodiment of the present invention, the first end of the first rope 7 is fixed on the winding wheel 9, and the first rope 7 winds around the positioning pulley 61 and then walks around the grooved pulley from top to bottom, further Yes, the first rope 7 passes through the diverting pulley 51 from bottom to top, after passing through the diversion pulley 51 to change direction, further, the first rope 7 passes through the sheave from top to bottom, and further, the first rope 7 winds from bottom to top Turning pulley 53, after changing direction through turning pulley 53, further, the first rope 7 goes around the warp sheave from top to bottom, and further, the first rope 7 goes around the line sheave from bottom to top, the first rope 7 The end is fixedly arranged on the rotating mechanical arm 2 .

Correspondingly, when the motor 4 rotates in the direction as shown in Figure 2, the first rope 7 has a stretching tendency, and the stretching amount is distributed to several sections of rope distances bounded by the diverting pulley 51 and the diverting pulley 53 through the routing of the first rope 7, And drive the rotating mechanical arm 2 to rotate as shown in Figure 2; Correspondingly, the second rope 8 has a slack tendency, and the slack is distributed to the steering pulley 52 and the steering pulley 54 by the second rope 8. The tension of the first rope 7 is equal to the length of the slack of the second rope 8, so that both the first rope 7 and the second rope 8 are kept under tension.

Fig. 3 is a schematic diagram of the winding of the second rope 8 of the joint module of the flexible-driven collaborative robotic arm of the embodiment of the three wire grooves in the embodiment of the present invention. Specifically, in the embodiment of the present invention, the starting end of the second rope 8 is fixed on the winding wheel 9, and the second rope 8 winds around the positioning pulley 62 and then goes around the wire sheave from bottom to top. Further, the first The second rope 8 goes around the diverting pulley 52 from top to bottom, after the diverting pulley 52 changes direction, further, the second rope 8 passes through the wire sheave from the bottom to the top, and further, the second rope 8 goes around the diverting pulley from the bottom to the top. 54, after changing the direction through the turning pulley 54, further, the second rope 8 winds around the warp sheave from bottom to top, and further, after the second rope 8 goes around the wire sheave from top to bottom, the end of the second rope 8 It is fixedly arranged on the rotating mechanical arm 2 .

Correspondingly, when the motor 4 rotates in the direction as shown in Figure 3, the second rope 8 has a stretching tendency, and the stretching amount is apportioned to several sections of rope distances bounded by the diverting pulley 52 and the diverting pulley 54 through the second rope 8. And drive the rotating mechanical arm 2 to rotate as shown in Figure 3; Correspondingly, the first rope 7 has a slack tendency, and the slack is distributed to the steering pulley 51 and the steering pulley 53 by the first rope 7. The tension of the first rope 7 is equal to the length of the slack of the second rope 8, so that both the first rope 7 and the second rope 8 are kept under tension.

In an optional embodiment, the joint module of the flexible-driven collaborative robotic arm provided by the present invention can be designed as an N-line groove. The larger the value of N, the corresponding increase in the number of steering pulleys is required. The number of rope segments in the circle also increases, the driving force brought by the motor is distributed more evenly on the rope, and the rotation of the rotating mechanical arm is more stable and smooth.

In an optional embodiment, the direction of rotation of the deflection pulley 5 is perpendicular or parallel to the direction of rotation of the groove wheel set 10;

In an optional embodiment, the wire groove wheel set 10 includes several wire groove wheels, and each wire groove wheel is provided with two wire grooves for matching ropes. Correspondingly, when the number of wire groove wheels is odd, the same rope The end is fixed on the rotating mechanical arm 2; correspondingly, when the number of the grooved wheels 10 is even, the end of the same rope is fixed on the driving mechanical arm 1.

In an optional embodiment, the first rope 7 and the second rope 8 are steel wire ropes.

In addition, remember that the diameter of the motor shaft is d, the diameter of the winding wheel is D, and the number of slots is N, then the reduction ratio of the rope-driven rotary joint module is N*D/d.

To sum up, the present invention provides a flexible-driven cooperative robot arm joint module. The motor is arranged on the driving robot arm, which reduces the load of the rotating robot arm, has good joint compliance, and has good safety force interaction; it is driven by a rope The joint structure is guided by the pulley block, so that the joint of the same output shaft is jointly driven by two steel wire ropes, which can be stretched and compressed, ensuring the reliability of the drive in the forward and reverse directions of the joint.

The above is a detailed introduction of a flexible-driven cooperative robotic arm joint module provided by the embodiment of the present invention. In this paper, specific examples are used to illustrate the principle and implementation of the present invention. The description of the above embodiment is only for helping Understand the method of the present invention and its core idea; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation and scope of application. In summary, the content of this specification is not It should be understood as a limitation of the present invention.

Claims (9)

1. A flexible-drive joint module of a cooperative mechanical arm is characterized by comprising a drive mechanical arm, a rotating mechanical arm, a connecting shaft, a motor, a first rope and a second rope;

the driving mechanical arm is hinged with the rotating mechanical arm through a connecting shaft;

the motor is arranged on the driving mechanical arm;

the initial end of the first rope and the initial end of the second rope are respectively wound on the output shaft of the motor along opposite directions,

the middle part of the first rope and the middle part of the second rope are wound through the connecting shaft along opposite directions respectively;

the tail end of the first rope is fixed on the rotating mechanical arm after passing through the driving mechanical arm or the tail end of the first rope is fixed on the driving mechanical arm after passing through the rotating mechanical arm,

the tail end of the second rope is wound through the driving mechanical arm and fixed on the rotating mechanical arm, or the tail end of the second rope is wound through the rotating mechanical arm and fixed on the driving mechanical arm;

the flexibly driven cooperative arm joint module further comprises a reel coaxially fixed on an output shaft of the motor; the leading end of the first rope and the leading end of the second rope are wound around the output shaft of the motor based on the reel.

2. The flexibly driven cooperative robotic arm joint module of claim 1, further comprising a diverting pulley;

at least one steering pulley is arranged on one surface of the rotary mechanical arm, and at least one steering pulley is arranged on the other surface of the rotary mechanical arm; the first rope is based on setting up rotate on the arm one side diverting pulley wire-wound rotate the arm, the second rope is based on setting up rotate on the arm another side diverting pulley wire-wound rotate the arm.

3. The flexibly driven cooperative robotic arm joint module of claim 2, wherein the first rope forms a plurality of first rope loops as it is looped around the connecting shaft, the first rope between two adjacent first rope loops transitioning based on the diverting pulley;

the second ropes form a plurality of second rope rings when being wound through the connecting shaft, and the second ropes between two adjacent second rope rings are transited based on the steering pulley.

4. The flexible driven cooperative robotic arm joint module of claim 1, further comprising a wireway wheel set comprising a number of wireway wheels; the wire groove wheel is coaxially and rotationally matched on the connecting shaft; any one of the line grooved wheels is provided with a plurality of line grooves, and the first rope and the second rope are respectively matched in the corresponding line grooves.

5. The flexibly driven joint module of a cooperative robot arm according to claim 4, further comprising a plurality of positioning pulleys respectively disposed at preset positions of the driving robot arm; the first and second ropes transition between the reel and the line duct based on corresponding positioning pulleys, respectively.

6. The flexibly driven cooperative robotic arm joint module of claim 2, wherein a rotational axis of the diverting pulley is perpendicular to a rotational axis of the wire chase wheel set.

7. The flexible driven cooperative robotic arm joint module of claim 4, wherein the wire chase wheel set comprises three wire sheaves, any one of the wire sheaves having two wire chases.

8. The flexibly driven cooperative arm joint module of claim 2, further comprising a plurality of said diverting pulleys; the two steering pulleys are arranged on the rotating mechanical arm, and the two steering pulleys are arranged on the driving mechanical arm.

9. The flexible driven cooperative robotic arm joint module of claim 1, wherein the first and second cables are steel cables.

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