CN105252530A - Six-degree-of-freedom large-stroke flexible parallel platform - Google Patents

Abstract

A six-degree-of-freedom large-stroke flexible parallel platform relates to a flexible parallel platform, in particular to a six-freedom large-stroke flexible parallel platform. The invention aims to solve the problem of contradiction between the high precision of the existing flexible parallel platform and the working space. The present invention includes an upper platform, a lower platform and six motion branch chains. The upper platform and the lower platform are arranged side by side from top to bottom. The lower surface of the upper platform is connected to the upper surface of the lower platform by three sets of motion branch chain components The motion branch chains are evenly distributed along the circumferential direction of the lower platform. The invention is used in the field of robots.

Description

A six-degree-of-freedom large-stroke flexible parallel platform

technical field

The invention relates to a flexible parallel platform, in particular to a six-degree-of-freedom large-stroke flexible parallel platform, which belongs to the field of robots.

Background technique

Mechanical drive and transmission has always been the foundation of the equipment manufacturing industry, and modern precision mechanical drive and transmission is an urgently needed supporting technology in the fields of microelectronics manufacturing, optoelectronics, aerospace equipment, ultra-precision machining, precision operation robots, and biomedical engineering. Traditional mechanisms are composed of rigid components connected in the form of kinematic pairs. There are inevitably gaps and frictions between the components that make up the kinematic pairs, which cannot meet the high-performance requirements such as high speed, high precision, and miniaturization. The compliant mechanism utilizes the deformation and self-recovery characteristics of elastic materials to eliminate the lost motion and mechanical friction in the transmission process, and can obtain ultra-high displacement resolution and precision. Due to the limitation of material properties, the traditional notch-type flexible hinge has a small range of motion, and it is difficult to adapt to some occasions with large corners. At the same time, in order to improve the stiffness and response speed of the flexible mechanism, the flexible mechanism is usually built in a parallel form, which further reduces the working space of the flexible parallel platform.

Contents of the invention

In order to solve the problem of contradiction between high precision and working space of the existing flexible parallel platform, the present invention further proposes a six-degree-of-freedom large-stroke flexible parallel platform.

The technical scheme adopted by the present invention to solve the above-mentioned problems is: the present invention comprises an upper platform, a lower platform and six motion branch chains, the upper platform and the lower platform are arranged side by side from top to bottom, and the lower surface of the upper platform passes through three groups of motions. The branch chain component is connected with the upper surface of the lower platform and the six motion branch chains are evenly distributed along the circumferential direction of the lower platform.

Further, each kinematic branch includes a cylinder pair and two flexible Hookee hinges, and the two flexible Hookee hinges are connected by a cylinder pair.

Further, each flexible Hookee hinge includes a core body, two brackets and a plurality of flexible rotating joints, the core body is a hexahedron, the two ends of one bracket are connected to two opposite sides of the core body through two flexible rotating joints, and the other Two ends of a support are connected to the other two opposite sides of the core body through two flexible rotating joints, and the two supports are arranged in a cross shape.

Further, each flexible rotary joint includes a first rotary joint and a second rotary joint, one end of the first rotary joint is connected to one end of the second rotary joint by car, a D-shaped flex plate is arranged inside the first rotary joint, and the second rotary joint There is an I-type flexible board in the section.

Further, there is a gap at the connection between the first rotating joint and the second rotating joint.

The beneficial effects of the present invention are as follows: 1. The reed type flexible rotary joint with large stroke can realize gapless motion within the range of ±30°, with high motion accuracy and resolution; 2. Two groups are formed by using 4 flexible rotary joints Orthogonal rotating pairs form a large-stroke flexible Hooke hinge, and then build a 6-UCU six-degree-of-freedom flexible parallel platform, which can achieve high-precision, high-rigidity, and high-response motion within a large range of motion.

Description of drawings

Fig. 1 is a schematic diagram of the overall structure of the present invention, Fig. 2 is a schematic diagram of the mechanism of the kinematic branch chain, Fig. 3 is a schematic diagram of the structure of the flexible Hooke hinge, Fig. 4 is a schematic diagram of the structure of the flexible rotary joint, Fig. 5 is a schematic diagram of the Hooke hinge on the upper and lower platforms A schematic diagram of the distribution of connection points.

detailed description

Specific embodiment 1: This embodiment is described in conjunction with FIG. 1. A six-degree-of-freedom large-stroke flexible parallel platform described in this embodiment includes an upper platform 1, a lower platform 2, and six motion branch chains 3. The upper platform 1 and the lower platform 2 are arranged side by side from top to bottom, and the lower surface of the upper platform 1 is connected to the upper surface of the lower platform 2 through three sets of said moving branch chain assemblies. Six moving branch chains 3 are evenly distributed along the circumferential direction of the lower platform 2. The lower platform 2 is the connection unit between the flexible parallel mechanism and the base, and is connected to the outside world through the threaded hole at the bottom; the upper platform 1 is the motion output end of the flexible mechanism, and the actuator can be connected through the threaded hole on the upper platform 1 to realize space Precision motion in six degrees of freedom.

Specific Embodiment 2: This embodiment is described in conjunction with FIG. 2 . Each motion branch chain 3 of a six-degree-of-freedom large-stroke flexible parallel platform described in this embodiment includes a cylindrical pair 3-1 and two flexible Hookee hinges 3 -2, two flexible Hooker hinges 3-2 are connected by a cylinder pair 3-1. Two flexible Hookee hinges 3-2 and a cylindrical pair 3-1 form a 6-UCU type branch chain, and the cylindrical pair 3-1 can allow two degrees of freedom of movement, that is, a circumferential rotation and an axial movement. The distribution of connection points of the Hooke hinge on the upper and lower platforms is shown in Figure 5. In Figure 5, the short sides and long sides of the hexagon A are equal respectively, and the half of the central angle corresponding to the short side A1A2 is β=15° , each short side and long side of the hexagon B are equal, and half of the central angle corresponding to the short side B1B2 is α=15°. The driving of the platform is applied to the axial movement in the cylinder pair 3-1, the rotation of the rotary joint in the Hooke hinge 3-2 and the movement on the cylinder pair 3-1 are passive links. The movement of six degrees of freedom in space can be realized through the coordinated movement of the driving motors on the six branch chains.

The rotation angle range of the flexible rotary joint adopted in the present invention is ±30°. Other components and connections are the same as those in the first embodiment.

Specific Embodiment 3: This embodiment is described in conjunction with FIG. 3 . Each flexible Hookee hinge 3-2 of a six-degree-of-freedom large-stroke flexible parallel platform described in this embodiment includes a core 3-2-1 and two brackets. 3-2-2 and a plurality of flexible rotary joints 3-2-3, the core body 3-2-1 is a hexahedron, and the two ends of a bracket 3-2-2 connect with the core through two flexible rotary joints 3-2-3 The two opposite sides of the body 3-2-1 are connected, and the two ends of the other support 3-2-2 are connected with the other two opposite sides of the core 3-2-1 through two flexible rotating joints 3-2-3 , the two brackets 3-2-2 are arranged in a cross shape. The core body 3 can also be spherical or other structures, and its surface is provided with four installation holes, and the four installation holes are respectively connected to the corresponding end of a bracket 3-2-2 through a flexible rotating joint, forming two groups of mutually orthogonal of the rotating pair. Other components and connections are the same as those in the second embodiment.

Specific Embodiment 4: This embodiment is described with reference to FIG. 4 . Each flexible rotary joint 3-2-3 of a six-degree-of-freedom large-stroke flexible parallel platform described in this embodiment includes a first rotary joint 3-2-3- 1 and the second rotating joint 3-2-3-2, one end of the first rotating joint 3-2-3-1 is connected with one end of the second rotating joint 3-2-3-2, and the first rotating joint 3- 2-3-1 is provided with a D-type flexible board 3-2-3-3, and the second rotating joint 3-2-3-2 is provided with an I-type flexible board 3-2-3-4. The main body of each flexible rotating joint 3-2-3 is cylindrical, and the elastic deformation of the D-type flexible board 3-2-3-3 and the I-type flexible board 3-2-3-4 arranged crosswise can realize the rotation Single-axis two-way limited rotation, fix the second rotating joint 3-2-3-2, apply torque on the first rotating joint 3-2-3-1, and fix the second rotating joint 3-2-3- The I-type flex plate 3-2-3-4 inside 2 will be elastically deformed, thereby realizing the gapless rotation between the first rotating joint 3-2-3-1 and the second rotating joint 3-2-3-2 ,vice versa. By changing the angle between the D-type flexible board 3-2-3-3 and the I-type flexible board 3-2-3-4, different rotation angles and rotational stiffness requirements can be met. Other components and connections are the same as those in the third embodiment.

Embodiment 5: This embodiment is described in conjunction with FIG. 4. The first rotating joint 3-2-3-1 and the second rotating joint 3-2-3 of a six-degree-of-freedom large-stroke flexible parallel platform described in this embodiment There is a gap 4 at the junction of -2. Other compositions and connections are the same as those in Embodiment 4.

The above description is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Anyone familiar with this field Those skilled in the art, without departing from the scope of the technical solution of the present invention, may use the technical content disclosed above to make some changes or modify equivalent embodiments with equivalent changes, but as long as they do not depart from the technical solution of the present invention, according to the technical content of the present invention Within the spirit and principles of the present invention, any simple modifications, equivalent replacements and improvements made to the above embodiments still fall within the scope of protection of the technical solutions of the present invention.

Claims (5)

1. A six-degree-of-freedom large-stroke flexible parallel platform, characterized in that: the six-degree-of-freedom large-stroke flexible parallel platform includes an upper platform (1), a lower platform (2) and six motion branch chains (3) , the upper platform (1) and the lower platform (2) are arranged side by side from top to bottom, and the lower surface of the upper platform (1) is connected with the upper surface of the lower platform (2) through three groups of the motion branch chain components and six motion branches The chains (3) are evenly distributed along the circumferential direction of the lower platform (2). 2. A kind of flexible parallel platform with six degrees of freedom and large stroke according to claim 1, characterized in that: each kinematic branch chain (3) comprises a cylinder pair (3-1) and two flexible Hooke hinges (3-1) 2), two flexible Hooke hinges (3-2) are connected by a cylinder pair (3-1). 3. A six-degree-of-freedom large-stroke flexible parallel platform according to claim 2, characterized in that: each flexible Hookee hinge (3-2) includes a core (3-2-1), two supports (3 -2-2) and a plurality of flexible revolving joints (3-2-3), the core body (3-2-1) is a hexahedron, and the two ends of a support (3-2-2) pass through two flexible revolving joints ( 3-2-3) is connected with the two opposite sides of the core (3-2-1), and the two ends of the other support (3-2-2) are connected with the two flexible rotating joints (3-2-3) The other two opposite sides of the core (3-2-1) are connected, and the two brackets (3-2-2) are arranged in a cross shape. 4. A six-degree-of-freedom large-stroke flexible parallel platform according to claim 3, characterized in that: each flexible rotary joint (3-2-3) includes a first rotary joint (3-2-3-1) and The second rotary joint (3-2-3-2), one end of the first rotary joint (3-2-3-1) is connected with one end of the second rotary joint (3-2-3-2), the first A D-type flexible board (3-2-3-3) is provided in the rotating joint (3-2-3-1), and an I-type flexible board (3-2-3-2) is provided in the second rotating joint (3-2-3-2). -2-3-4). 5. A six-degree-of-freedom large-stroke flexible parallel platform according to claim 4, characterized in that: the first rotating joint (3-2-3-1) and the second rotating joint (3-2-3-2) There is a gap (4) at the connection of the .