A Parallel Mechanism with Few Joints and Two Rotation Degrees of Freedom

Abstract

The invention discloses a parallel mechanism with a small number of joints and two rotational freedom degrees. The parallel mechanism comprises a stationary platform, a movable platform and three branch chains, wherein the three branch chains are connected with the stationary platform and the movable platform. One end of an intermediate connecting rod of the first branch chain is connected with the movable platform through a rotating pair, and the other end of the intermediate connecting rod of the first branch chain is connected with the stationary platform through a rotating pair. One end of a first upper connecting rod of the second branch chain is connected with the movable platform through a hooke joint, the other end of the first upper connecting rod of the second branch chain is connected with the one end of a first lower connecting rod through a moving pair, and the other end of the first lower connecting rod is connected with the stationary platform through a rotating pair. One end of a second upper connecting rod of the third branch chain is connected with the movable platform through a rotating pair, the other end of the second upper connecting rod of the third branch chain is connected with one end of a second lower connecting rod through a moving pair, and the other end of the second lower connecting rod is connected with the movable platform through a hooke joint. The parallel mechanism contains the small number of single-freedom-degree joints and is high in structural rigidity; and the one-to-one correspondence relationship exists between input and output, motion is decoupled completely, a control model is simple, and practicability is high.

Description

technical field [0001] The invention belongs to the field of robots, in particular to a parallel mechanism. Background technique [0002] The parallel mechanism with few degrees of freedom has the advantages of simple structure, low manufacturing cost and easy control. In recent years, it has become one of the research hotspots in the field of robotics and mechanisms. Among all kinds of parallel mechanisms with few degrees of freedom, the two-degrees of freedom rotating parallel mechanism is an important branch of parallel mechanisms with few degrees of freedom. And telescope positioning, as well as antenna and solar panel azimuth tracking and other fields, have very great application prospects. The two-degree-of-freedom rotating parallel mechanism includes a two-degree-of-freedom spherical mechanism and a two-degree-of-freedom rotating parallel mechanism without a meeting point. The two rotational axes of the two-degree-of-freedom spherical parallel mechanism are continuou...

AI Technical Summary

Problems solved by technology

The two-degree-of-freedom rotating parallel mechanism includes a two-degree-of-freedom spherical mechanism and a two-degree-of-freedom rotating parallel mechanism without a meeting point. The two rotational axes of the two-degree-of-freedom spherical parallel mechanism are continuous, but it must satisfy that the axis of the rotating pair meets at a certain point. It is very difficult to process and manufacture due to the geometrical requirements of points; however, there are not many existing two-degree-of-freedom parallel mechanisms without converging points that have two continuous shafts, and the number of single-degree-of-freedom kinematic pairs is large, and the overall stiffness is low, such as The institutions proposed in Chinese patent CN201010136427.6, etc.

The mechanism proposed by CN201610303875.8 has two continuous shafts, but the mechanism is not completely decoupled

The above two-rotation parallel mechanisms with two continuous shafts also have problems such as a large number of single-degree-of-freedom joints.

Images