Type Synthesis And Analysis Of Several Regular Polyhedron Coupling Mechanisms

Spatial coupling mechanism is a new type of mechanism. It not only presents the complex multi ring mesh geometry, and the movement of the branches is no longer relatively independent. Each branch is shown as an interrelated coupling motion. At present, the spatial coupling mechanism has been widely used in people’s production and life. Such as magic ball toys, astronomical telescope, robot, large construction machinery and other fields can see the coupling mechanism. However, the type synthesis of coupling mechanism is still at the primary stage, lacking of systematic and deep research. So it is a new research hotspot to study the type synthesis of spatial coupling mechanism.Based on several regular polyhedron structures, this paper discusses a new method for the synthesis of corresponding spatial coupling mechanism, and a series of spatial coupling mechanism model is developed. And the position inverse solution of a kind of 1T symmetric coupling mechanism is analyzed, and the results are verified by the simulation software of Matlab and Solid Works. It provides the basis for the analysis of the position inverse solution of the symmetric coupling mechanism. The main contents are as follows:Firstly, a new method for the design of coupling mechanism based on several polyhedron structures is proposed. The general idea of this method is to design a reasonable parallel mechanism model with different degrees of freedom, and then to design the coupling mechanism with different structures and degrees of freedom by adding the coupling chains with different constraints. The design steps of the synthesis of the coupling mechanism based on the Octahedron structure,Dodecahedron structure and four kinds of Archimedes polyhedron are given in detail.Then, two parallel mechanism models are designed based on the Octahedron structure, and three parallel mechanism models are designed based on the geometric features of the Dodecahedron structure. Then, the structures of Truncated cube, Cuboctahedron, Truncated octahedron and Truncated tetrahedron are selected as the research objects. By judging the constraint conditions and adding different coupling branches, the corresponding effective spatial coupling mechanisms are synthesized.At the same time, based on the geometry characteristics of the Archimedes polyhedron structure, when the moving platform and fixed platform were selected, decoupling the polyhedral structure and the parallel branch with a different structure will be designed. Combined with each other, the parallel branches are combined to obtain the non-symmetrical parallel mechanism. By designing and adding coupling chains with different motion constraints, the asymmetric coupling mechanism is designed.Finally,with the 1T symmetric coupling mechanism as the object, the coupling branches of the mechanism are decomposed. Taking the branch as the research object, the result of the position inverse solution of the symmetric coupling mechanism is solved by screw theory. And the results are verified by the simulation software of Matlab. A new idea of the position inverse solution analysis for the symmetric coupling mechanism is put forward.