CN102825600A - Parallel mechanism containing RRRR closed-loop subchain - Google Patents

Abstract

The invention discloses a parallel mechanism containing an RRRR closed-loop subchain. The parallel mechanism comprises the RRRR closed-loop subchain and an executing mechanism subchain. The RRRR closed-loop subchain can be used for controlling a first turntable to move in a plane where the RRRR closed-loop subchain is arranged, and two-degree-of-freedom motion of the space of a moving platform can be realized through the motion of the first turntable. According to the invention, the motion of one turntable on the plane is controlled through the closed-loop subchain so that the two-degree-of-freedom motion of the space of the moving platform is realized; the parallel mechanism has the advantages of compact structure and simplicity in control; and all active bars are connected to a rack and can be made into light bars, and therefore, the mechanism is small in motion inertia and good in dynamics performance.

Description

A Parallel Mechanism Containing RRRR Closed-loop Subchain

technical field

The invention relates to the field of robots, in particular to a parallel mechanism with RRRR closed-loop sub-chains. the

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; completely symmetrical parallel mechanism has better isotropy. 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. the

Contents of the invention

The purpose of the present invention is to provide a parallel mechanism with RRRR closed-loop sub-chains, which solves the shortcoming of the traditional parallel mechanism that multiple drivers of one branch chain cannot be connected to the frame at the same time. the

The present invention achieves the above object through the following technical solutions: a parallel mechanism with RRRR closed-loop sub-chains, including RRRR closed-loop sub-chains and actuator sub-chains. the

The RRRR closed-loop sub-chain is formed by connecting the first active rod, the second active rod, the first connecting rod, the second connecting rod and the frame. One end of the first active rod is connected to the frame through the first rotating pair. The other end of an active rod is connected to the first connecting rod through the second rotating pair, the other end of the first connecting rod is connected to the second connecting rod through the third rotating pair, and the other end of the second connecting rod is connected to the second driving rod through the fourth rotating pair. Rod connection, the other end of the second active rod is connected to the frame through the first rotating pair, the movement of the first active rod and the second active rod drives the movement of the first connecting rod and the second connecting rod to control the first turntable in the RRRR closed-loop sub-chain motion in the plane. the

The sub-chain of the actuator is formed by connecting the first turntable, the second turntable, the third connecting rod, the fourth connecting rod, the fifth connecting rod, the sixth connecting rod and the moving platform. The first connecting rod is connected, the first turntable is connected with the third connecting rod through the fifth rotating pair, the first turntable is connected with the fourth connecting rod through the sixth rotating pair, and the other end of the third connecting rod is connected with the moving platform through the seventh rotating pair It is connected with the fifth connecting rod, the other end of the fourth connecting rod is connected with the moving platform through the eighth rotating pair, the moving platform is connected with the sixth connecting rod through the ninth rotating pair, and the other end of the fifth connecting rod is connected with the sixth connecting rod through the tenth rotating pair. The second turntable is connected, the other end of the sixth connecting rod is connected to the second turntable through the eleventh turning pair, the second turntable is connected to the frame through the first turning pair, the movement of the first turntable in the plane can realize the space of the moving platform Two-degree-of-freedom movement, especially the RRRR closed-loop sub-chain and the actuator sub-chain can make a full circle around the first rotary pair. the

The rotation axes of the first rotating pair, the second rotating pair, the third rotating pair, and the fourth rotating pair are parallel to each other, the third connecting rod is parallel to the fourth connecting rod, the fifth connecting rod is parallel to the sixth connecting rod, etc. long parallel. the

The outstanding advantages of the present invention are:

1. Through the closed-loop sub-chain to control the movement of the mechanism, the branch chain of the mechanism can have multiple active rods connected to the frame;

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

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

Description of drawings

Fig. 1 is a schematic diagram of the first structure of a parallel mechanism containing RRRR closed-loop sub-chains according to the present invention. the

Fig. 2 is a schematic diagram of the second structure of a parallel mechanism containing RRRR closed-loop sub-chains according to the present invention. the

Fig. 3 is a first working schematic diagram of a parallel mechanism including RRRR closed-loop sub-chains according to the present invention. the

Fig. 4 is a second working schematic diagram of a parallel mechanism including RRRR closed-loop sub-chains according to the present invention. the

Detailed ways

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

Comparing Figure 1 and Figure 2, a parallel mechanism with RRRR closed-loop sub-chain includes RRRR closed-loop sub-chain and actuator sub-chain. the

The RRRR closed-loop sub-chain is formed by connecting the first active rod 2, the second active rod 5, the first connecting rod 4, the second connecting rod 7 and the frame 1, and one end of the first active rod 2 passes through the first rotating pair 22 Connected to the frame 1, the other end of the first active rod 2 is connected to the first connecting rod 4 through the second rotating pair 3, the other end of the first connecting rod 4 is connected to the second connecting rod 7 through the third rotating pair 23, the second The other end of the two connecting rods 7 is connected with the second active rod 5 through the fourth rotating pair 6, and the other end of the second active rod 5 is connected with the frame 1 through the first rotating pair 22. The first active rod 2 and the second active rod 5 The movement drives the movement of the first connecting rod 4 and the second connecting rod 7 to control the movement of the first turntable 8 in the plane where the closed-loop sub-chain of the five-bar mechanism is located. the

The sub-chain of the actuator is formed by connecting the first turntable 8, the second turntable 21, the third connecting rod 12, the fourth connecting rod 11, the fifth connecting rod 17, the sixth connecting rod 18 and the moving platform 15. The turntable 8 is connected to the first connecting rod 4 through the third turning pair 23, the first turntable 8 is connected to the third connecting rod 12 through the fifth turning pair 10, and the first turntable 8 is connected to the fourth connecting rod 11 through the sixth turning pair 9. The other end of the third connecting rod 12 is connected to the moving platform 15 and the fifth connecting rod 17 through the seventh rotating pair 14, the other end of the fourth connecting rod 11 is connected to the moving platform 15 through the eighth rotating pair 13, and the moving platform 15 passes through The ninth rotating pair 16 is connected to the sixth connecting rod 18, the other end of the fifth connecting rod 17 is connected to the second turntable 21 through the tenth rotating pair 19, and the other end of the sixth connecting rod 18 is connected to the second turntable through the eleventh rotating pair 20. The turntable 21 is connected, and the second turntable 21 is connected with the frame 1 through the first rotating pair 22. The movement of the first turntable 8 in the plane can realize the space two-degree-of-freedom movement of the moving platform, especially the RRRR closed-loop sub-chain and the actuator The sub-chain can make a complete rotation around the first rotating pair. the

The axes of rotation of the first rotating pair 22, the second rotating pair 3, the third rotating pair 23, and the fourth rotating pair 6 are parallel to each other, the third connecting rod 12 is equal in length to the fourth connecting rod 11, and the fifth connecting rod 15 is parallel with the sixth connecting rod 18 equal lengths. the

Referring to Fig. 3 and Fig. 4, the movement of the first turntable 8 in the plane can realize the two-degree-of-freedom movement of the movable platform 15 in space. the

Claims (1)

1. a parallel institution that contains RRRR closed loop subchain comprises RRRR closed loop subchain and executing agency's subchain, it is characterized in that its structure and connected mode are:

Said RRRR closed loop subchain is formed by connecting first driving lever, second driving lever, first connecting rod, second connecting rod and frame; First driving lever, one end is connected on the frame through first revolute pair; The first driving lever other end is connected with first connecting rod through second revolute pair, and the first connecting rod other end is connected with second connecting rod through the 3rd revolute pair, and the second connecting rod other end is connected with second driving lever through the 4th revolute pair; The second driving lever other end is connected with frame through first revolute pair

Said executing agency subchain is formed by connecting first turntable, second turntable, third connecting rod, the 4th connecting rod, the 5th connecting rod, the 6th connecting rod and moving platform; First turntable is connected with first connecting rod through the 3rd revolute pair; First turntable is connected with third connecting rod through the 5th revolute pair, and first turntable is connected with the 4th connecting rod through the 6th revolute pair, and the third connecting rod other end is connected with the 5th connecting rod with moving platform through the 7th revolute pair; The 4th connecting rod other end is connected with moving platform through the 8th revolute pair; Moving platform is connected with the 6th connecting rod through the 9th revolute pair, and the 5th connecting rod other end is connected with second turntable through the tenth revolute pair, and the 6th connecting rod other end is connected with second turntable through the 11 revolute pair; Second turntable is connected with frame through first revolute pair

The rotation of said first revolute pair, second revolute pair, the 3rd revolute pair, the 4th revolute pair is parallel to each other, and third connecting rod is isometric parallel with the 4th connecting rod, and the 5th connecting rod is isometric parallel with the 6th connecting rod.

Images