2-PRT and PRS spatial parallel robotic mechanism with three degrees of freedom (DOF)

Abstract

The invention discloses a spatial parallel robotic mechanism with three degrees of freedom (DOF). The mechanism consists of a motion platform, a fixed platform and three branched chains for linking the two platforms; two of the three branched chains have the same structure and respectively comprise a hooke joint, a rotating joint, a prismatic joint and connecting rods from top to bottom, wherein the connecting rods are arranged among the hooke joint, the rotating joint and the prismatic joint; and the other branched chain comprises a ball joint, a rotating joint, a prismatic joint and connecting rods from top to bottom, wherein the connecting rods are arranged among the ball joint, the rotating joint and the prismatic joint. A working platform of the mechanism can realize motion output with one translational DOF and two rotations; and the mechanism has less joints and a motion pair only has 13 DOFs in total, thereby effectively solving the problem that a parallel mechanism is easy to bend, reverse and deform due to overabundance of DOFs of the motion pair. In addition, a rotating head with two DOFs is connected in series to the motion platform, and therefore, a hybrid robot with five DOFs, which can be used in occasions of machining at high speed, can be designed.

Description

【Technical field】 [0001] The invention relates to the technical field of robots and advanced manufacturing, in particular to a parallel robot mechanism with few degrees of freedom that realizes space-translation and two-rotation. 【Background technique】 [0002] The parallel robot mechanism can be defined as: the upper and lower platforms (fixed platform and moving platform) are connected by two or more kinematic branch chains, each kinematic branch chain is composed of connecting rods and kinematic pairs, and the kinematic platform has two or more A mechanism with more than two degrees of freedom driven in parallel. Parallel robot mechanisms are widely used in technical fields such as large-scale analog equipment, robots, CNC machine tools, sensors, micro-manipulators, engraving machines, and measuring machines. The Stewart platform is a typical parallel robot mechanism, which has 6 degrees of freedom. It was first used in parallel robots and CNC machine tools. parallel me...

AI Technical Summary

Problems solved by technology

[0004] At present, a 5-degree-of-freedom hybrid robot is constructed by connecting a 2-degree-of-freedom rotating head in series based on a 3-degree-of-freedom parallel robot mechanism as a positioning component, which has broad application prospects in the field of high-speed machining. The positioning parts of the parallel structure have the problem of insufficient rigidity caused by many rods and many kinematic pairs. It is necessary to create a new model that meets the requirements of the kinematic form and has fewer kinematic pairs and high rigidity.

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