CN102990658B - Parallel mechanism containing prr kinematic pair open loop subchain and prrrr kinematic pair closed loop subchain - Google Patents

Abstract

A parallel mechanism containing a prr kinematic pair open loop subchain and a prrrr kinematic pair closed loop subchain comprises a four-rod mechanism closed loop subchain and an execution mechanism subchain. The four-rod mechanism closed loop subchain can control a third connection rod to move in a plane of the four-rod mechanism closed loop subchain, and movement of a first connection rod and the third connection rod can achieve space movement of a movable platform. The parallel mechanism utilizes one closed loop subchain to control achievement of space movement of the closed loop subchain, the first connection rod and the third connection rod and achieve space movement of the movable platform accordingly. The parallel mechanism has the advantages of being compact in structure, simple to control, small in mechanism movement inertia and good in dynamic performance due to the fact that all the connection rods are connected onto a frame and can be made into light rods.

Description

Parallel Mechanism Containing prr Kinetic Pair Open-loop Sub-chain and prrrr Kinematic Pair Closed-loop Sub-chain

technical field

The invention relates to the field of robots, in particular to a parallel mechanism including a prr motion pair open-loop sub-chain and a prrrr motion pair closed-loop sub-chain.

Background technique

Compared with the traditional serial mechanism, the parallel mechanism has the following characteristics: no cumulative error and high precision; the driving device can be placed on the fixed platform or close to the fixed platform, so that the moving part is light in weight, high in speed and good in dynamic response; Compact structure, high rigidity, large bearing capacity. Since the parallel mechanism itself is relatively complex, if the branch contains closed loops, the mechanism will be more complicated. Therefore, generally speaking, the symmetrical parallel mechanism with branches without closed loops will have the most typical properties. However, if the closed-loop application Properly, the performance of the parallel mechanism will be more excellent, such as the famous delta mechanism. In addition, in the existing parallel mechanism, the branch chain is limited by the connection method. Generally, there is only one active rod connected to the drive fixed on the frame. The chain may adopt the method of connecting multiple active rods in series on the branch chain. However, the structure of the parallel mechanism with multiple branch chains is complex and difficult to control. Multiple active rods connected in series on the branch chain will affect the kinematic performance of the parallel mechanism.

Contents of the invention

The purpose of the present invention is to provide a parallel mechanism including a prr motion pair open-loop sub-chain and a prrrr motion pair closed-loop sub-chain, so as to solve the disadvantage of a traditional parallel mechanism that one branch chain and multiple drives cannot be connected to the frame at the same time.

The present invention achieves above-mentioned object through following technical scheme: the parallel mechanism that contains prr motion pair open-loop sub-chain and prrrr motion pair closed-loop sub-chain, comprises an executive mechanism sub-chain and a four-bar mechanism closed-loop sub-chain, and its structure and connection mode are :

The sub-chain of the actuator is formed by connecting the first connecting rod 11, the second connecting rod 15, the first slider 13, the first Hooke hinge 7, the moving platform 4 and the frame 1, and one end of the first connecting rod 11 passes through The first rotating pair 2 is connected on the frame 1, the other end of the first connecting rod 11 is connected with the first sliding block 13 through the first moving pair 12, and the other end of the first sliding block 13 is connected with the second connecting rod through the second rotating pair 14. One end of the rod 15 is connected, and the other end of the second connecting rod 15 is connected with the lower top support 9 of the first Hooke hinge through the third rotating pair 10, and the upper top support 8 of the first Hooke hinge 7 is connected with the moving joint through the fourth rotating pair 5. Platform 4 is connected at one end,

Described four-bar mechanism closed-loop child chain is made up of the 3rd connecting rod 20, the 4th connecting rod 16, the 5th connecting rod 25, the 6th connecting rod 23, the second slider 18, the first bearing 22, the second Hooke hinge 26 and the frame 1, one end of the third connecting rod 20 is connected to the frame 1 through the fifth rotating pair 3, the other end of the third connecting rod 20 is connected with the second sliding block 18 through the second moving pair 19, and the third connecting rod 20 is connected to the second slider 18 through the second moving pair 19. The other end of the second slide block 18 is connected with the fourth connecting rod 16 through the sixth rotating pair 17, and the other end of the fourth connecting rod 16 and one end of the fifth connecting rod 25 are connected with the lower top of the second Hooke hinge 26 through the seventh rotating pair 30. The upper support 27 of the second Hooke hinge 26 is connected to the other end of the moving platform 4 through the eighth rotating pair 6, and the other end of the fifth connecting rod 25 is connected to the sixth connecting rod 23 through the ninth rotating pair 24. The other end of the sixth connecting rod 23 is connected to the first support 22 fixed on the third connecting rod 20 through the tenth rotating pair 21 .

The rotation axes of the first moving pair, the second moving pair, the first turning pair and the fifth turning pair are parallel to each other, and the rotation axes of the fourth turning pair and the eighth turning pair are parallel to each other.

The outstanding advantages of the present invention are:

1. The movement of the mechanism is controlled by a closed-loop sub-chain, and the branch chain of the mechanism can have multiple connecting rods connected to the frame;

2. All connecting rods are connected to the frame, and the rods are made of light rods, the mechanism has small inertia and good dynamic performance;

3. By installing various end effectors for different purposes on the moving platform, this mechanism can be applied to tasks such as grabbing, turning, handling, and stacking.

Description of drawings

Fig. 1 is a schematic diagram of the first structure of a parallel mechanism including a prr motion pair open-loop sub-chain and a prrrr motion pair closed-loop sub-chain according to the present invention.

Fig. 2 is a second structural schematic diagram of the parallel mechanism including the prr motion pair open-loop sub-chain and the prrrr motion pair closed-loop sub-chain according to the present invention.

Fig. 3 is a schematic diagram of a rack of a parallel mechanism including a prr motion pair open-loop sub-chain and a prrrr motion pair closed-loop sub-chain according to the present invention.

Fig. 4 is a schematic diagram of a moving platform of a parallel mechanism including a prr kinematic pair open-loop sub-chain and a prrrr kinematic pair closed-loop sub-chain according to the present invention.

Fig. 5 is a schematic diagram of the first Hooke hinge of the parallel mechanism including the prr motion pair open-loop sub-chain and the prrrr motion pair closed-loop sub-chain according to the present invention.

Fig. 6 is a schematic diagram of the second Hooke hinge of the parallel mechanism including the prr motion pair open-loop sub-chain and the prrrr motion pair closed-loop sub-chain according to the present invention.

Detailed ways

The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Referring to Figure 1, Figure 3, Figure 4, Figure 5 and Figure 6, the parallel mechanism containing the prr motion pair open-loop sub-chain and the prrrr motion pair closed-loop sub-chain includes an actuator sub-chain and a four-bar mechanism closed-loop sub-chain, Its structure and connection method are:

The sub-chain of the actuator is formed by connecting the first connecting rod 11, the second connecting rod 15, the first slider 13, the first Hooke hinge 7, the moving platform 4 and the frame 1, and one end of the first connecting rod 11 passes through The first rotating pair 2 is connected on the frame 1, the other end of the first connecting rod 11 is connected with the first sliding block 13 through the first moving pair 12, and the other end of the first sliding block 13 is connected with the second connecting rod through the second rotating pair 14. One end of the rod 15 is connected, and the other end of the second connecting rod 15 is connected with the lower top support 9 of the first Hooke hinge through the third rotating pair 10, and the upper top support 8 of the first Hooke hinge 7 is connected with the moving joint through the fourth rotating pair 5. Platform 4 is connected at one end,

Described four-bar mechanism closed-loop child chain is made up of the 3rd connecting rod 20, the 4th connecting rod 16, the 5th connecting rod 25, the 6th connecting rod 23, the second slider 18, the first bearing 22, the second Hooke hinge 26 and the frame 1, one end of the third connecting rod 20 is connected to the frame 1 through the fifth rotating pair 3, the other end of the third connecting rod 20 is connected with the second sliding block 18 through the second moving pair 19, and the third connecting rod 20 is connected to the second slider 18 through the second moving pair 19. The other end of the second slide block 18 is connected with the fourth connecting rod 16 through the sixth rotating pair 17, and the other end of the fourth connecting rod 16 and one end of the fifth connecting rod 25 are connected with the lower top of the second Hooke hinge 26 through the seventh rotating pair 30. The upper support 27 of the second Hooke hinge 26 is connected to the other end of the moving platform 4 through the eighth rotating pair 6, and the other end of the fifth connecting rod 25 is connected to the sixth connecting rod 23 through the ninth rotating pair 24. The other end of the sixth connecting rod 23 is connected to the first support 22 fixed on the third connecting rod 20 through the tenth rotating pair 21 .

The rotation axes of the first moving pair, the second moving pair, the first turning pair and the fifth turning pair are parallel to each other, and the rotation axes of the fourth turning pair and the eighth turning pair are parallel to each other.

Referring to Fig. 2, Fig. 3, Fig. 4, Fig. 5 and Fig. 6, the movement of the first connecting rod and the third connecting rod in the plane can realize the spatial movement of the moving platform 4.

Claims (1)

1. contain the parallel institution of prr kinematic pair open loop subchain and prrrr kinematic pair closed-loop subchain, comprise executing agency's subchain and a four-bar mechanism closed-loop subchain, its structure and connected mode are:

Described executing agency subchain is formed by connecting by first connecting rod, second connecting rod, the first slide block, the first Hooke's hinge, moving platform and frame, first connecting rod one end is connected in frame by the first revolute pair, the first connecting rod other end is connected with the first slide block by the first moving sets, the first slide block other end is connected with second connecting rod one end by the second revolute pair, the second connecting rod other end is connected with the lower topmast of the first Hooke's hinge by the 3rd revolute pair, the upper topmast of the first Hooke's hinge is connected with moving platform one end by the 4th revolute pair

Described four-bar mechanism closed-loop subchain is by third connecting rod, double leval jib, 5th connecting rod, six-bar linkage, second slide block, first bearing, second Hooke's hinge and frame are formed by connecting, third connecting rod one end is connected in frame by the 5th revolute pair, the third connecting rod other end is connected with the second slide block by the second moving sets, the second slide block other end is connected with double leval jib by the 6th revolute pair, the double leval jib other end is connected with the lower topmast of the second Hooke's hinge by the 7th revolute pair with the 5th connecting rod one end, the upper topmast of the second Hooke's hinge is connected with the moving platform other end by the 8th revolute pair, the 5th connecting rod other end is connected with six-bar linkage by the 9th revolute pair, the six-bar linkage other end is connected with the first bearing be fixed on third connecting rod by the tenth revolute pair,

Described first moving sets, the second moving sets, the first revolute pair, the 5th revolute pair rotation are parallel to each other, and the 4th revolute pair, the 8th revolute pair rotation are parallel to each other.