CN102975203A - High-speed five-degree of freedom parallel manipulator - Google Patents

Abstract

The invention discloses a high-speed five-degree-of-freedom parallel manipulator, which includes a fixed frame, a moving platform, a two-degree-of-freedom wrist, and five branch chains with the same structure arranged between the fixed frame and the moving platform. The platform produces three-dimensional translational motion; the moving platform includes a central plate, two sets of angular gear sets, four connecting rods and a fixed connecting rod; the fixed connecting rods and the above four connecting rods are radially evenly distributed on the central plate, One end of the fixed connecting rod is fixedly connected to the center plate, and one end of the four connecting rods is fixedly connected to the rotating shaft of the split-angle bevel gear in the two-component angular gear set, and the meshing between the two-component angular gear set and the central bevel gear The function transmits the motion to the two-degree-of-freedom wrist, thereby generating two-degree-of-freedom controllable rotation. The invention has symmetrical structure, uniform force, small mass of moving parts, good dynamic performance, can realize high-speed movement, and satisfies the requirements of complicated pick-and-place operations.

Description

A high-speed five-degree-of-freedom parallel manipulator

technical field

The invention relates to a robot, in particular to a high-speed parallel mechanism with five degrees of freedom in space.

Background technique

At present, domestic research on spatial five-degree-of-freedom parallel mechanisms is still focused on mechanisms in the fields of machining, spraying, and measurement. However, research on spatial five-degree-of-freedom parallel mechanisms that can achieve high-speed movement for materials is still lacking.

Contents of the invention

In view of the above-mentioned prior art, the present invention provides a high-speed five-degree-of-freedom parallel manipulator. The structure of the mechanism in the present invention is symmetrical, the force is uniform, the mass of the moving parts is small, and the dynamic performance is good. It can realize high-speed movement and meet complex pick-and-place operations. requirements.

In order to solve the above-mentioned technical problems, the technical scheme realized by a five-degree-of-freedom parallel manipulator of the present invention is: comprising a fixed frame, a moving platform, a two-degree-of-freedom wrist, and five arms with the same structure arranged between the fixed frame and the moving platform. branch chain; five driving devices are fixedly connected to the fixed frame; each branch chain includes a near frame rod, two parallel and equal-length far frame rods, an upper connecting shaft and a lower connecting shaft; each In the branch chain, one end of the near-frame rod is fixedly connected to the output end of a driving device fixed on the fixed frame, and the driving device provides a degree of freedom for the near-frame rod to rotate or move; The other end is fixedly connected with the upper connecting shaft; one end of the two parallel remote frame rods is respectively hinged with the upper connecting shaft ball, and the other end of the two parallel remote frame rods is respectively connected with the lower shaft-ball hinge; the lower connecting shaft in each branch chain, the upper connecting shaft and the two parallel arranged and equal-length remote frame rods form a parallelogram structure; the moving platform includes a central plate, Two sets of angular gear sets and four connecting rods; each set of angular gear sets includes a central bevel gear and two sub-angle bevel gears; the central bevel gear is rotatably connected with the central plate, and the central bevel gear The axis coincides with the axis of rotation; the split-angle bevel gear is connected to the center plate in rotation, the axes of the two split-angle bevel gears and the axis of the central bevel gear are perpendicular to one point, and the two-angle split bevel gears are arranged on both sides of the center bevel gear. side and meshed with the central bevel gear; the moving platform is also provided with a fixed connecting rod, the fixed connecting rod and the above four connecting rods are radially evenly distributed on the central plate, and the four connecting rods One end is respectively affixed to the rotation shafts of the sub-angle bevel gears in the two sets of angular gear sets, one end of the fixed connecting rod is affixed to the center plate, and the other ends of the four connecting rods and the fixed connecting rod are respectively It is affixed to the five lower connecting shafts in the five branch chains with the same structure; the two-degree-of-freedom wrist is affixed to the center plate, and two sets of gear transmission mechanisms are arranged around the two-degree-of-freedom wrist, and each set of gear transmission mechanisms includes A large gear and a small gear meshed with each other. The large gear in each set of gear transmission mechanism is coaxially arranged with the central bevel gear of each set of angular gear sets in the moving platform. The pinion is connected to the two-degree-of-freedom wrist One of the input shafts is fixedly connected and arranged coaxially; the two sets of gear transmission mechanisms provide two power inputs for the two-degree-of-freedom wrist to realize the two-dimensional controllable rotation of the two-degree-of-freedom wrist; Under the driving action of the device, the lower connecting shafts in the five branch chains with the same structure move, and then drive the moving platform to generate three-dimensional translational motion. At the same time, the four lower connecting shafts drive the central bevel gear through the angular gear set The center plate rotates; thus, the moving platform can have translational degrees of freedom in three directions and two local rotational degrees of freedom at the same time, and the above two partial rotational degrees of freedom are transferred by two sets of gear transmission mechanisms arranged around the wrist with two degrees of freedom. It is converted into a two-dimensional controllable rotation of the two-degree-of-freedom wrist.

Compared with prior art, the beneficial effect of the present invention is:

The advantages and positive effects of the present invention are: under the driving action of the five branch chains, through the transmission action of the two sets of angular gear sets arranged on the moving platform, the moving platform can realize three-dimensional translational motion and the relative movement of the two central bevel gears. Based on the rotation of the center plate, the rotation of the central bevel gear is converted into two power inputs of the two-degree-of-freedom wrist through two sets of gear amplification mechanisms, and then drives the two-degree-of-freedom wrist to realize two-dimensional space rotation. The structure of the mechanism is symmetrical, the force is uniform, the mass of the moving parts is small, and the dynamic performance is good. It can realize high-speed movement and meet the requirements of complex pick-and-place operations.

Description of drawings

1 is a schematic diagram of the overall structure of a five-degree-of-freedom parallel manipulator of the present invention;

Fig. 2 is the structural schematic diagram of the middle moving platform of the present invention;

Fig. 3 is a structural schematic diagram of a two-degree-of-freedom wrist and a moving platform in the present invention.

In the picture:

1-Drive device 2-Fixed frame 3-Near frame rod

4-upper connecting shaft 5a, 5b-far frame rod 6-lower connecting shaft

7-moving platform 8-center plate 9a~9d-connecting rod

9e-fixed connecting rod 10aa~10bb-central bevel gear 10a~10b-fractional bevel gear

11a, 11c- large gear 11b, 11d- small gear 12- two degrees of freedom wrist

Detailed ways

The present invention will be further described in detail below in combination with specific embodiments.

As shown in Figure 1, a five-degree-of-freedom parallel manipulator of the present invention includes a fixed frame 2, a moving platform 7, a two-degree-of-freedom wrist 12, and five supports with the same structure arranged between the fixed frame 2 and the moving platform 7. chain.

Five driving devices 1 are affixed to the fixed frame 2; each branch chain includes a near-frame rod 3, an upper connecting shaft 4, two parallel and equal-length far-mounting rods 5a, 5b and a lower connecting shaft 6.

In each branch chain, one end of the near frame bar 3 is fixedly connected to the output end of a drive device 1 fixed on the fixed frame 2, and the drive device 1 provides a degree of freedom for the near frame bar 3 to rotate or move The other end of the near frame rod 3 is fixedly connected with the upper connecting shaft 4; one end of the two parallel far frame rods 5a, 5b is respectively ball-hinged with the upper connecting shaft 4, and the two parallel The other ends of the far frame rods 5a, 5b are respectively ball-hinged with the lower connecting shaft 6; the lower connecting shaft 6, the upper connecting shaft 4 and the two parallel arrangements and equal lengths in each branch chain The far frame rods 5a and 5b form a parallelogram structure.

As shown in Figure 2, the moving platform 7 includes a central plate 8, two sets of angular gear sets and four connecting rods 9a~9d; each set of angular gear sets includes a central bevel gear 10aa (or 10bb) and two A sub-angle bevel gear 10a (or 10b). The central bevel gear 10aa (or 10bb) is rotationally connected with the central plate 8, and the axis of the central bevel gear 10aa (or 10bb) coincides with its axis of rotation; The plate 8 is connected in rotation, the axes of the two angle-dividing bevel gears 10a (or 10b) are perpendicular to the axis of the central bevel gear at one point, and the two angle-dividing bevel gears 10a (or 10b) are arranged on the central bevel gear 10aa (or 10bb ) on both sides and meshes with the central bevel gear 10aa (or 10bb).

The moving platform 7 is also provided with a fixed connecting rod, the fixed connecting rod 9e and the above-mentioned four connecting rods are radially evenly distributed on the central plate 8, and one end of the four connecting rods is connected with two groups of connecting rods respectively. The rotating shafts of the angle-dividing bevel gears in the angle-dividing gear set are affixed, one end of the fixed connecting rod is affixed to the center plate 8, and the other ends of the four connecting rods and the fixed connecting rods 9a to 9d are respectively connected to The five lower connecting shafts 6 in the five branch chains with the same structure are fixedly connected.

As shown in Figure 3, the two-degree-of-freedom wrist 12 is fixed on the central plate 8, two sets of gear transmission mechanisms 11a and 11b are arranged around the two-degree-of-freedom wrist 12, and each set of gear transmission mechanisms 11a (or 11b) includes A large gear 11a (or 11c) and a small gear 11b (or 11d) meshing with each other, the large gear 11a (or 11c) in each set of gear transmission mechanism 11a (or 11b) is respectively connected with each set of the moving platform 7 The central bevel gear 10aa (or 10bb) of the split-angle gear set is coaxially arranged, and the pinion 11b (or 11d) is fixedly connected to an input shaft of the two-degree-of-freedom wrist 12, and is coaxially arranged; in the present invention, each group In the gear amplification mechanism, the large gear and the pinion are meshed, and the gear transmission mechanism converts the relative rotation of the central bevel gears 10aa and 10bb relative to the central plate 8 into the power input of the two-degree-of-freedom wrist 12, thereby realizing the two-degree-of-freedom. Two-dimensional controllable rotation of the wrist 12 with degrees of freedom.

The transmission process of the above-mentioned five-degree-of-freedom parallel manipulator is that, under the driving action of the five driving devices 1, the lower connecting shaft 6 in the five branch chains with the same structure moves, that is, the driving device 1 is a close connection with it. The frame rod 3 provides a degree of freedom of rotation or movement, and the lower connecting shaft 6 of the branch chain is driven by the two parallel and long-term frame rods 5a, 5b of the branch chain to generate translational motion, and then the moving platform 7 is driven to generate a three-dimensional translational motion; At the same time, the four lower connecting shafts drive the central bevel gear to rotate relative to the central plate through the angle-dividing gear set; thus, the moving platform 7 can not only have translation degrees of freedom in three directions, but also have two partial rotation degrees of freedom , using the amplification effect of the two sets of gear transmission mechanisms arranged around the two-degree-of-freedom wrist to transform the above-mentioned two partial rotational degrees of freedom into two-dimensional controllable rotation of the two-degree-of-freedom wrist (end effector).

Compared with the prior art, the present invention differs in that:

The moving platform is composed of a center plate, two sets of angular gear sets and a fixed connecting rod, wherein the relative movement of the lower connecting shaft connected to the two sets of angular gear sets can be converted into a central bevel gear relative to the center through the split angle gear set. For the rotation of the plate, since the fixed connecting rod is fixedly connected to the center plate, the moving platform can not only have translational degrees of freedom in three directions, but also have two partial rotational degrees of freedom. Furthermore, the amplification effect of the gear transmission mechanism is used to convert the two partial rotation degrees of freedom into the controllable motion of the wrist with two degrees of freedom.

The invention has the advantages of symmetrical structure, flexible movement, uniform force, high precision, long service life, easy realization of high-speed movement, and meets the requirements of complex pick-and-place operations.

Although the present invention has been described above in conjunction with the drawings, the present invention is not limited to the above-mentioned specific embodiments, and the above-mentioned specific embodiments are only illustrative rather than restrictive. Under the inspiration, many modifications can be made without departing from the gist of the present invention, and these all belong to the protection of the present invention.

Claims (1)

1. high speed parallel manipulator with five freedom degrees comprises fixed mount (2), moving platform (7), two-freedom wrist (12) and is arranged in five side chains that structure is identical between described fixed mount (2) and the moving platform (7);

Be connected with five drive units (1) on the described fixed mount (2); Described every side chain comprises nearly hack lever (3), two parallel and isometric hack levers far away, upper connecting axle (4) and a lower connecting axle (6);

In every side chain, an end of described nearly hack lever (3) is fixedly connected with the output of a drive unit (1) on being fixed in described fixed mount (2), and this drive unit (1) provides one to rotate or one-movement-freedom-degree for nearly hack lever (3); The other end of described nearly hack lever (3) and described upper connecting axle (4) are connected; One end of described two parallel hack levers far away respectively with described upper connecting axle (4) ball-joint, the other end of described two parallel hack levers far away respectively with described lower connecting axle (6) ball-joint; Described lower connecting axle in every side chain, described upper connecting axle and described two are arranged in parallel and isometric hack lever far away consists of a parallelogram sturcutre;

It is characterized in that:

Described moving platform (7) comprises a central plate (8), two component angle gear trains and four connecting rods; Every component angle gear train comprises a center bevel gear and two subangle bevel gears; Described center bevel gear and described central plate (8) are rotationally connected, and the axis of described center bevel gear and pivot center overlap; Described subangle bevel gear and central plate (8) are rotationally connected, and the axis of two subangle bevel gears is vertical with the axis of described center bevel gear to be met at a bit, and two subangle bevel gear arrangements mesh in the center bevel gear both sides and with center bevel gear;

Described moving platform also is provided with a stationary links on (7), described stationary links and above-mentioned four connecting rods are radial equipartition at described central plate (8), one end of described four connecting rods respectively with two component angle gear trains in the turning cylinder of subangle bevel gear affixed, one end of described stationary links and described central plate (8) are affixed, and the other end of described four connecting rods and stationary links respectively five lower connecting axles in the side chain identical with five structures is affixed;

Described two-freedom wrist (12) is fixed on the described central plate (8), two groups of gear drives of two-freedom wrist (12) arranged around, every group of gear drive comprises an intermeshing gear wheel and a pinion, gear wheel in every group of gear drive respectively with described moving platform (7) in the coaxial setting of center bevel gear of every component angle gear train, one power shaft of described pinion and two-freedom wrist is affixed, and coaxial setting; Described two groups of gear drives are that described two-freedom wrist (12) provides two power inputs, realize the two-dimentional controllable rotary of described two-freedom wrist (12);

Under the driving effect of five drive units (1), article five, lower connecting axle (6) motion in the side chain that structure is identical, and then drive the motion of moving platform (7) generation three-dimensional translating, meanwhile, four lower connecting axles rotate relative to central plate by the described center bevel gear of subangle gear set drive; Thereby, moving platform both can have the translational degree of freedom of three directions, simultaneously have again two partial rotational frees degree, utilize two groups of gear drives of two-freedom wrist arranged around above-mentioned two partial rotational frees degree to be converted into the two-dimentional controllable rotary of two-freedom wrist.

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