CN110653798A

CN110653798A - Three-branch three-movement two-rotation non-overconstrained parallel robot

Info

Publication number: CN110653798A
Application number: CN201910912981.XA
Authority: CN
Inventors: 曹文熬; 杨训; 李坤
Original assignee: China University of Geosciences
Current assignee: China University of Geosciences
Priority date: 2019-09-25
Filing date: 2019-09-25
Publication date: 2020-01-07

Abstract

The invention discloses a three-branch three-shift two-turn non-overconstrained parallel robot, which comprises a rack, a movable platform, a first branch, a second branch and a third branch, wherein the first branch, the second branch and the third branch are connected in parallel between the rack and the movable platform, have the same structure and are driven by double motors; the first branch and the second branch are sequentially provided with a parallelogram coupling driving assembly, a sixth revolute pair, a first driven rod, a seventh revolute pair and a Hooke hinge assembly from the rack to the movable platform; and the third branch comprises a driving motor III, a third expansion sleeve component, a driving rod III, a 4S parallelogram component and a ninth revolute pair from the rack to the movable platform in sequence. The advantages are that: the robot mechanism has the advantages of less branches, low cost, simple structure, less interference, high rigidity, high bearing capacity, high precision, small motion inertia, good power performance and easy control.

Description

Three-branch three-movement two-rotation non-overconstrained parallel robot

Technical Field

The invention relates to the technical field of robots, in particular to a three-branch three-shift two-turn non-overconstrained parallel robot.

Background

The parallel robot really draws wide attention in the last 90 th century, has the advantages of high rigidity, high speed, strong flexibility, light weight and the like, and forms an important part of an industrial robot together with the serial robot. The method is most widely applied to light industries such as food, medicine, electronics and the like, and has incomparable advantages in the aspects of material handling, packaging, sorting and the like. With the increasingly wide application of parallel robots in the market, the parallel robots become new forces for the growth of industrial robots.

In the prior document, an invention patent with publication number CN107553471A discloses a five-degree-of-freedom parallel robot containing a double-composite equivalent ball pair, an invention patent with publication number CN105598947A discloses a three-dimensional translation and two-dimensional rotation five-degree-of-freedom parallel robot mechanism, an invention patent with publication number CN105437217A discloses a 4PSS +1PRPU type five-degree-of-freedom parallel robot, an invention patent with publication number CN105033988A discloses a two-dimensional rotation and three-dimensional movement five-degree-of-freedom parallel robot mechanism, an invention patent with publication number CN104608130A discloses a 3SPS +2SPR + R type five-degree-of-freedom parallel mechanism, an invention patent with publication number CN103085059A discloses a one-rotation and four-translation driving five-degree-of-freedom parallel robot, an invention patent with publication number CN102554919A discloses a five-degree-of-freedom parallel robot containing a double-composite equivalent ball pair, an invention patent with publication number CN101693366A discloses a five-degree-of-freedom parallel robot mechanism, an invention patent with publication number CN 1013736 discloses a five-degree-of-freedom parallel robot without, the invention patent with publication number CN101491899 discloses a five-degree-of-freedom parallel robot mechanism, the invention patent with publication number CN1772443A discloses a three-dimensional translation and two-dimensional rotation five-degree-of-freedom parallel robot mechanism, the invention patent with publication number CN1546287A discloses a space five-degree-of-freedom parallel robot mechanism, the mechanisms involved in the above patents all adopt a five-branch parallel connection form to realize five degrees of freedom, the structure is complex, the cost is increased, the kinematic parameters are complex, the interference is easy, and the control is not easy. The invention patent with the publication number of CN109352631A discloses a three-branch five-degree-of-freedom parallel platform, and a single branch of the mechanism of the invention has the advantages of more related rod pieces, complex structure, increased cost, increased related kinematic relation parameters and complex kinematic solution.

Disclosure of Invention

The invention aims to provide a three-branch three-movement two-rotation non-overconstrained parallel robot aiming at the prior technical situation, a three-branch parallel structure is adopted to realize three-dimensional movement and two-dimensional rotation, and compared with a five-branch parallel robot mechanism which is used for realizing five degrees of freedom, the three-branch three-movement two-rotation non-overconstrained parallel robot has the advantages of reduced branches, reduced cost and less interference; the non-overconstrained robot has the advantages of low requirement on processing and manufacturing precision, convenience in manufacturing, easiness in assembly, high rigidity, strong bearing capacity, high precision, small motion inertia, good power performance, easiness in control and the like.

In order to achieve the purpose, the invention adopts the following technical scheme:

a three-branch three-shift two-turn non-overconstrained parallel robot comprises a rack, a movable platform, a first branch, a second branch and a third branch, wherein the first branch, the second branch and the third branch are connected in parallel between the rack and the movable platform, have the same structure and are driven by double motors; the first branch and the second branch are sequentially provided with a parallelogram coupling driving assembly, a sixth revolute pair, a first driven rod, a seventh revolute pair and a Hooke hinge assembly from the rack to the movable platform; the parallelogram coupling driving assembly is connected with the first driven rod through a sixth revolute pair, and the axis of the sixth revolute pair is perpendicular to the central line of the first driven rod; the first driven rod is connected with the hook hinge assembly through a seventh revolute pair, and the axis of the seventh revolute pair is overlapped with the center line of the first driven rod; the hook hinge assembly is arranged on the movable platform; the axis of the seventh revolute pair passes through the geometric center of the hook hinge assembly; the axis of the hook hinge assembly close to the revolute pair of the movable platform is vertical to, parallel to or obliquely crossed with the plane of the movable platform; the parallelogram coupling driving assembly comprises a first driving motor, a first expansion sleeve part, a first driving rod, a second driving motor, a second expansion sleeve part, a second driving rod, a third revolute pair, a fourth revolute pair, an auxiliary driving rod, a fifth revolute pair and a parallel rod; the driving rod I is fixedly connected with the driving motor I through a first expansion sleeve part, the driving rod II is fixedly connected with the driving motor II through a second expansion sleeve part, the auxiliary driving rod is connected with the driving rod I through a third revolute pair, the parallel rod is connected with the driving rod II through a fifth revolute pair, and the auxiliary driving rod is connected with the parallel rod through a fourth revolute pair; the axis of the first driving motor is superposed with the axis of the second driving motor; the axis of the first driving motor, the axis of the second driving motor, the axis of the third rotating pair, the axis of the fourth rotating pair and the axis of the fifth rotating pair are parallel to each other; the axis of the sixth revolute pair is vertical to the rotation axis of each joint of the parallelogram coupling driving assembly; the third branch comprises a driving motor III, a third expansion sleeve component, a driving rod III, a 4S parallelogram component and a ninth revolute pair from the rack to the movable platform in sequence; the 4S parallelogram component comprises a ball pair connecting rod, a connecting rod I, a connecting rod II, a T-shaped connecting rod, a first ball pair, a second ball pair, a third ball pair and a fourth ball pair; one end of the driving rod III is fixedly connected with the driving motor tee through a third expansion sleeve component, the other end of the driving rod III is fixedly connected with the upper end of a ball pair connecting rod, two sides of the lower end of the ball pair connecting rod are respectively connected with one end of a connecting rod I and one end of a connecting rod II through a first ball pair and a second ball pair, the other ends of the connecting rod I and the connecting rod II are respectively connected with two sides of the upper end of a T-shaped connecting rod through a third ball pair and a fourth ball pair, and the lower end of the T-shaped connecting rod is connected with the movable platform through a; and the axis of the ninth revolute pair is vertical to the plane of the movable platform.

The invention has the beneficial effects that:

the motor is fixed on the frame, so that the weight of each branch and the movable platform is reduced, and the inertia is reduced; the robot mechanism which adopts a three-branch parallel structure to realize three-movement two-rotation five-freedom-degree has the advantages of reduced branches, reduced cost, simple structure and less interference compared with the existing five-branch parallel robot mechanism which realizes five-freedom-degree; the non-overconstrained system parts are simple to machine and manufacture, low in precision requirement and easy to assemble; the number of the rods involved in each single branch is small, and the rods and the kinematic pairs connected with the rods form a driving parallelogram, so that the rods are kept parallel, and the mechanism has the advantages of good stability, compact structure, convenience in driving and easiness in control.

Drawings

FIG. 1 is a schematic structural diagram of a parallel robot according to the present invention;

fig. 2 is a schematic structural diagram of a parallelogram coupling driving assembly of the present invention.

Description of the labeling: 1. the driving rod I, the driving rod II, the driving rod auxiliary, the driving rod 5, the parallel rod 6, the driven rod I, the driven rod 7, the driving rod III, the driving rod 8, the ball pair connecting rod 9, the connecting rod I, the connecting rod 10, the connecting rod II, the T-shaped connecting rod 12, the movable platform I, the first branch, the second branch, the third branch, the M1, the driving motor I, the M2, the driving motor II, the M3, the driving motor III, the R1, the first expansion sleeve component, the R2, the second expansion sleeve component, the R3, the third rotating pair, the R4, the fourth rotating pair, the R5, the fifth rotating pair, the R6, the sixth rotating pair, the R7, the seventh rotating pair, the R8, the third expansion sleeve component, the R9, the ninth rotating pair, the U1, the hooke assembly, the S1, the first ball pair, the S2, the second ball pair, the S3, the third ball pair 4, the fourth ball pair.

Detailed Description

Referring to fig. 1-2, a three-branch three-shift two-turn non-overconstrained parallel robot includes a frame 1, a movable platform 12, and a first branch i, a second branch ii and a third branch iii driven by a single motor, which have the same structure and are connected in parallel between the frame 1 and the movable platform 12 and are driven by two motors; the first branch I and the second branch II are sequentially provided with a parallelogram coupling driving assembly, a sixth revolute pair R6, a first driven rod 6, a seventh revolute pair R7 and a Hooke hinge assembly U1 from the rack 1 to the movable platform 12; the parallelogram coupling driving assembly is connected with the driven rod I6 through a sixth revolute pair R6, and the axis of the sixth revolute pair R6 is perpendicular to the central line of the driven rod I6; the first driven rod 6 is connected with the Hooke hinge assembly U1 through a seventh revolute pair R7, and the axis of the seventh revolute pair R7 is overlapped with the central line of the first driven rod 6; the hook hinge assembly U1 is arranged on the movable platform 12; the axis of the seventh revolute pair R7 passes through the geometric center of the Hooke hinge assembly U1; the axis of the revolute pair of the hook hinge assembly U1 close to the movable platform 12 is vertical to, parallel to or oblique to the plane of the movable platform 12, and the axis of the revolute pair of the hook hinge assembly U1 close to the movable platform 12 shown in FIG. 1 is vertical to the plane of the movable platform 12; the parallelogram coupling driving assembly comprises a first driving motor M1, a first expansion sleeve part R1, a first driving rod 2, a second driving motor M2, a second expansion sleeve part R2, a second driving rod 3, a third revolute pair R3, a fourth revolute pair R4, an auxiliary driving rod 4, a fifth revolute pair R5 and a parallel rod 5; the driving rod I2 is fixedly connected with a driving motor I M1 through a first expansion sleeve part R1, the driving rod II 3 is fixedly connected with a driving motor II M2 through a second expansion sleeve part R2, the auxiliary driving rod 4 is connected with the driving rod I2 through a third revolute pair R3, the parallel rod 5 is connected with the driving rod II 3 through a fifth revolute pair R5, and the auxiliary driving rod 4 is connected with the parallel rod 5 through a fourth revolute pair R4; the axis of the first driving motor M1 is superposed with the axis of the second driving motor M2; the axis of the first driving motor M1, the axis of the second driving motor M2, the axis of the third revolute pair R3, the axis of the fourth revolute pair R4 and the axis of the fifth revolute pair R5 are parallel to each other; the axis of the sixth revolute pair R6 is vertical to the rotation axis of each joint of the parallelogram coupling driving assembly; the third branch III sequentially comprises a driving motor III M3, a third expansion sleeve component R8, a driving rod III 7, a 4S parallelogram component and a ninth revolute pair R9 from the machine frame 1 to the movable platform 12; the 4S parallelogram component comprises a ball pair connecting rod 8, a first connecting rod 9, a second connecting rod 10, a T-shaped connecting rod 11, a first ball pair S1, a second ball pair S2, a third ball pair S3 and a fourth ball pair S4; one end of the driving rod III 7 is fixedly connected with a driving motor III M3 through a third expansion sleeve component R8, the other end of the driving rod III 7 is fixedly connected with the upper end of the ball pair connecting rod 8, two sides of the lower end of the ball pair connecting rod 8 are respectively connected with one ends of the connecting rod I9 and the connecting rod II 10 through a first ball pair S1 and a second ball pair S2, the other ends of the connecting rod I9 and the connecting rod II 10 are respectively connected with two sides of the upper end of the T-shaped connecting rod 11 through a third ball pair S3 and a fourth ball pair S4, and the lower end of the T-shaped connecting rod 11 is connected with the movable platform 12 through a ninth revolute pair R9; the axis of the ninth revolute pair R9 is perpendicular to the plane of the movable platform 12.

It should be understood that the above-mentioned embodiments are merely preferred embodiments of the present invention, and not intended to limit the scope of the invention, therefore, all equivalent changes in the principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A three-branch three-shift two-turn non-overconstrained parallel robot is characterized in that: the device comprises a rack, a movable platform, a first branch, a second branch and a third branch, wherein the first branch, the second branch and the third branch are connected in parallel between the rack and the movable platform, have the same structure and are driven by double motors; the first branch and the second branch are sequentially provided with a parallelogram coupling driving assembly, a sixth revolute pair, a first driven rod, a seventh revolute pair and a Hooke hinge assembly from the rack to the movable platform; the parallelogram coupling driving assembly is connected with the first driven rod through a sixth revolute pair, and the axis of the sixth revolute pair is perpendicular to the central line of the first driven rod; the first driven rod is connected with the hook hinge assembly through a seventh revolute pair, and the axis of the seventh revolute pair is overlapped with the center line of the first driven rod; the hook hinge assembly is arranged on the movable platform; the axis of the seventh revolute pair passes through the geometric center of the hook hinge assembly; the axis of the hook hinge assembly close to the revolute pair of the movable platform is vertical to, parallel to or obliquely crossed with the plane of the movable platform; the parallelogram coupling driving assembly comprises a first driving motor, a first expansion sleeve part, a first driving rod, a second driving motor, a second expansion sleeve part, a second driving rod, a third revolute pair, a fourth revolute pair, an auxiliary driving rod, a fifth revolute pair and a parallel rod; the driving rod I is fixedly connected with the driving motor I through a first expansion sleeve part, the driving rod II is fixedly connected with the driving motor II through a second expansion sleeve part, the auxiliary driving rod is connected with the driving rod I through a third revolute pair, the parallel rod is connected with the driving rod II through a fifth revolute pair, and the auxiliary driving rod is connected with the parallel rod through a fourth revolute pair; the axis of the first driving motor is superposed with the axis of the second driving motor; the axis of the first driving motor, the axis of the second driving motor, the axis of the third rotating pair, the axis of the fourth rotating pair and the axis of the fifth rotating pair are parallel to each other; the axis of the sixth revolute pair is vertical to the rotation axis of each joint of the parallelogram coupling driving assembly; the third branch comprises a driving motor III, a third expansion sleeve component, a driving rod III, a 4S parallelogram component and a ninth revolute pair from the rack to the movable platform in sequence; the 4S parallelogram component comprises a ball pair connecting rod, a connecting rod I, a connecting rod II, a T-shaped connecting rod, a first ball pair, a second ball pair, a third ball pair and a fourth ball pair; one end of the driving rod III is fixedly connected with the driving motor tee through a third expansion sleeve component, the other end of the driving rod III is fixedly connected with the upper end of a ball pair connecting rod, two sides of the lower end of the ball pair connecting rod are respectively connected with one end of a connecting rod I and one end of a connecting rod II through a first ball pair and a second ball pair, the other ends of the connecting rod I and the connecting rod II are respectively connected with two sides of the upper end of a T-shaped connecting rod through a third ball pair and a fourth ball pair, and the lower end of the T-shaped connecting rod is connected with the movable platform through a; and the axis of the ninth revolute pair is vertical to the plane of the movable platform.