CN119036418A

CN119036418A - Three-translation parallel robot mechanism with passive closed-loop constraint branched chain

Info

Publication number: CN119036418A
Application number: CN202411392698.6A
Authority: CN
Inventors: 梁栋; 张珺鹏; 姚福林; 刘天佑; 简云; 韩志强
Original assignee: Tianjin Polytechnic University
Current assignee: Tiangong University
Priority date: 2024-10-08
Filing date: 2024-10-08
Publication date: 2024-11-29

Abstract

The present invention discloses a three-translational parallel robot mechanism with a passive closed-loop constraint branch chain. The mechanism consists of a moving platform, a static platform, three identical branches connecting the moving and static platforms, and an intermediate branch chain. The three identical branches are evenly arranged at intervals of 120° along the circumference of the static platform. The three identical branches are each composed of an active arm and a driven arm, and the active arm and the driven arm are connected by a ball joint. The intermediate branch chain consists of an intermediate component and six auxiliary rods respectively connecting the static platform and the moving platform. Among them, two Hooke's hinges are used at both ends of the auxiliary rod to connect the intermediate component with the static platform or the moving platform. The mechanism can realize three spatial translations, and has the advantages of compact structure, high flexibility, and reduced use of bearings.

Description

Three-translation parallel robot mechanism with passive closed-loop constraint branched chain

Technical Field

The invention belongs to the field of industrial robots, and particularly relates to a three-translation parallel robot mechanism with a passive closed-loop constraint branched chain.

Background

The manufacturing industry is a main support of national economy and is also a main battlefield of national economy 'innovative driving, transformation and upgrading'. In recent years, industrial robot technology has rapidly developed and is widely applied to the fields of aviation/aerospace, automobiles, electronics, foods, medical treatment and the like.

Tandem robots and parallel robots are two common forms of industrial robots. Compared with the serial robots, the parallel robots have the advantages of high speed, small error accumulation, high dynamic response and the like, and are complementary to the serial robots in application and are widely studied in recent years. Particularly, a parallel robot with a small degree of freedom is attracting attention in academia and industry due to its excellent dynamic characteristics.

Disclosure of Invention

The four-branched-chain parallel robot mechanism provided by the invention has the advantages of strong flexibility, low manufacturing cost and simple structure, and can realize three-dimensional translation.

The invention relates to a three-translation parallel robot mechanism with a passive closed-loop constraint branched chain. The invention mainly comprises a static platform part, a movable platform part, and three identical branched chains (named as a first branched chain, a second branched chain and a third branched chain respectively) and a middle branched chain which are arranged between the static platform and the movable platform.

The static platform part comprises a static platform frame, three motors corresponding to the three same branched chains, a speed reducer device fixedly connected with the motors and a small connecting piece connected with the middle branched chain. Wherein, the drive unit composed of three groups of motors and a reducer device fixedly connected with the motors is circumferentially arranged on the static platform frame at 120 degrees. And a flange plate is arranged on the upper surface of the static platform, so that the installation of subsequent engineering is facilitated. The small connecting piece connected with the middle branched chain is fixed on the lower surface of the static platform frame.

The three identical branched chains consist of a driving arm, a ball shaft and a driven arm. Wherein, the driving arm is fixedly connected with the output shaft of the speed reducer. The ball axle is fixed at the tail end of the driving arm. The driven arm is connected with the ball shaft in a ball pair mode. The middle branched chain consists of a triangular piece, a small connecting piece, a hook hinge and a rod piece. Wherein, three little connecting pieces are linked firmly respectively to the upper and lower surface of triangular piece. And two ends of the rod piece are respectively connected with the static platform and the triangular piece by adopting Hooke hinges, or the movable platform and the triangular piece. The rotating shaft directions of the three upper rods are the same, and the rotating shaft directions of the three lower rods are the same.

The movable platform part consists of a movable platform frame, a ball shaft, an end effector and a small connecting piece. Wherein, the end effector is fixedly connected with the center of the movable platform frame. The small connecting piece is fixedly connected to the upper surface of the movable platform and is connected with three rod pieces at the lower end of the middle branched chain in a Hooke hinge mode. The ball shaft is fixedly connected to the movable platform frame, and the ball shaft is circumferentially arranged on the movable platform frame at intervals of 120 degrees.

Compared with the existing mechanism, the invention has the advantages that:

The three-translation parallel robot mechanism with the passive closed-loop constraint branched chain has the characteristics of high speed, high flexibility and the like. As the whole mechanism is widely applied to the ball pair, the use of the bearing is reduced as a whole. Meanwhile, the middle branched chain is added to restrain the rotation of the movable platform, so that the mechanism realizes three-translation, the structure of the mechanism is compact, and the flexibility of the whole mechanism is improved.

Drawings

FIG. 1 is a schematic diagram of a three-translational parallel robot mechanism with a passive closed-loop constraint branch;

FIG. 2 is a schematic view of the structure of the static platform portion (without small connectors) of the present invention;

FIG. 3 is a schematic view of the structure of the actuator arm portion of the present invention in three identical branches;

FIG. 4 is a schematic structural view of a driven arm of three identical branches according to the present invention;

FIG. 5 is a schematic view of the structure of the intermediate branch and small connector of the present invention;

FIG. 6 is a schematic view of the structure of the movable platform part (without small connectors) of the present invention

Detailed Description

The present invention is described in further detail below with reference to the drawings to enable those skilled in the art to practice the invention by referring to the description.

Referring to fig. 1, the three-translation parallel robot mechanism with the passive closed-loop constraint branched chain consists of a static platform part I, a movable platform part IV, three identical branched chains II and an intermediate branched chain III, wherein the three identical branched chains II and the intermediate branched chain III are arranged between the static platform part and the movable platform part.

The static platform section I (without small connectors) is shown in fig. 2. The static platform part I consists of a static platform frame 1, a driving motor 3, a speed reducer 2 and a small connecting piece 7. Wherein, the driving motor 3 is fixedly connected with the speed reducer 2 to form a driving module of the mechanism. The three groups of driving modules are circumferentially arranged on the static platform frame 1 at intervals of 120 degrees along the static platform frame 1 and are fixedly connected with the static platform frame 1. The flange plate is arranged in the center of the upper surface of the static platform frame 1, so that the installation of subsequent engineering is facilitated. The three small connecting pieces 7 are fixedly connected to the center of the lower surface of the static platform frame 1, and the three small connecting pieces 7 are arranged in an equilateral triangle.

The movable platform section IV (without small connectors) is shown in fig. 6. The movable platform part IV consists of a movable platform frame 10, a ball shaft 5, an end effector 11 and a small connecting piece 7. Wherein, three ball axles 5 are arranged on the movable platform frame 10 along the circumference of the movable platform frame 10 at intervals of 120 degrees, and are fixedly connected with the movable platform frame 10. The end effector 11 is disposed at a central position of the movable platform frame 10 and is fixedly connected with the movable platform frame 10. The three small connecting pieces 7 are fixedly connected to the center of the upper surface of the movable platform frame 10, and the three small connecting pieces 7 are arranged in an equilateral triangle.

The three identical branches II are each composed of a driving arm part and a driven arm 6. The driving arm portion is composed of a driving arm 4 and a ball shaft 5, as shown in fig. 3. The ball shaft 5 is fixedly connected to the output end of the driving arm 4. The input end of the driving arm 4 is fixedly connected with the output shaft of the speed reducer. The follower arm 6 is shown in fig. 4. The driven arm 6 is connected with the driving arm part and the movable platform part IV respectively by adopting ball pairs.

The intermediate branch III is composed of a triangle 9, a bar 8, and a small connector 7, as shown in fig. 5. Wherein, the upper and lower surfaces of the triangle 9 are respectively fixedly connected with three small connecting pieces 7. In fig. 5, two ends of the upper three rods 8 are respectively connected with the small connecting piece 7 at the upper end of the triangular piece 9 and the small connecting piece 7 in the static platform part I through hook hinges. In fig. 5, two ends of the three rods 8 at the lower end are respectively connected with the small connecting piece 7 at the lower end of the triangular piece 9 and the small connecting piece 7 in the movable platform part IV through hook hinges. The three rods 8 at the upper end are always parallel in the moving process, and the axes of the hook hinges are the same. The three rods 8 at the lower end are always parallel in the movement process, and the axes of the hook hinges are the same.

The above embodiments are merely illustrative of the preferred embodiments of the present invention and are not intended to limit the scope of the present invention, and various modifications and improvements made by those skilled in the art to the technical solution of the present invention should fall within the protection scope defined by the claims of the present invention without departing from the design spirit of the present invention.

Claims

1. A three-translation parallel robot mechanism with passive closed-loop constraint branched chains comprises a static platform unit, a dynamic platform unit, and three identical branched chains and one middle branched chain which are arranged between the static platform and the dynamic platform. The static platform part consists of a static platform frame, a driving motor, a speed reducer and a connecting piece. The driving motors and the speed reducers are fixedly connected, and the three groups of driving motors and the speed reducers are uniformly arranged at intervals of 120 degrees along the circumferential direction of the static platform and are fixed on the static platform frame. The three connecting pieces are fixedly connected to the center of the lower surface of the static platform, and form an equilateral triangle. And the flange plate is arranged on the static platform frame, so that the follow-up engineering application is facilitated. The movable platform consists of a movable platform frame, an end effector, a connecting piece and a ball shaft. Wherein, ball axle, end effector, and connecting piece all link firmly on moving platform frame. The three same branched chains (respectively named as a first branched chain, a second branched chain and a third branched chain are all composed of a driving arm, a ball shaft and a driven arm, and the driving arm and the driven arm are connected by adopting a ball pair, wherein the driving arm is fixedly connected with an output shaft of the speed reducer, the middle branched chain is composed of a triangular piece, a connecting piece, a hook hinge and a rod piece, wherein the upper side and the lower side of the triangular piece are respectively fixedly connected with the three connecting pieces, and the two ends of the rod piece are respectively connected with the triangular piece and a static platform or the triangular piece and a movable platform by adopting the hook hinge.

2. The three-translation parallel robot mechanism with the passive closed-loop constraint branched chains according to claim 1, wherein the structure of the intermediate branched chains is characterized.

3. The three-translation parallel robot mechanism with the passive closed-loop constraint branched chains as claimed in claim 1, wherein the three parallel robot mechanisms are characterized by the integral structure of three identical branched chains.

4. The three-translation parallel robot mechanism with the passive closed-loop constraint branched chains of claim 1 is characterized by the design of a movable platform.