The Analysis Of Tensegrity Variable Stiffness Spring

The tensegrities are characterized by their own structural specificity,self-balancing and self-supporting properties,which reflects the phenomenon of continuous pull and intermittent pressure in nature.In recent years,tensegrity structures have been constantly applied as tensegrity robots,structures in bionics and biology.At present,tensegrity structures are considered as one of the cutting-edge topics,and have widely attracted attention from scholars in different areas of the world.The research on the tensegrity structures is mainly focused on the shape and optimization of structure,stability,topology and so on.Based on the previous research,this paper will study the calculation and adjustment of the structural pre-stress,the stiffness analysis of the structural and the splicing method of the structural unit.The specific process is as follows: firstly,the unit structure of the tensegrity is divided,the nodes of the three-dimensional spatial structure are expressed on the two-dimensional plane without considering the true node position of the structure,and the construction of the structure from the unit module to the structure of the overall module form.The nodes of the structural unit are expressed,through the structure of the force to establish the tensegrity structure of the equilibrium matrix,the matrix decomposition of the structure and have the self-stress mode and displacement mode,through fixed the different nodes of the structure or components to analyze the stability of the structure.Then,the material of the tensegrity structure is selected and the strength of the components is checked and the stiffness matrix of the tensegrity structure is established.Because of the existence of pretightening forces,the stiffness matrix in the structure includes the elastic stiffness matrix and the geometry stiffness matrix.The calculation method of the preload tension force is analyzed,including the fish swarm optimization algorithm,simplifying the same type of structural component algorithm and the same proportion of structural components to increase the length of the method.The model for two-layer tensegrity structures is established,and the influence of the parameter’s change and the amount of preload on the stiffness of the structure is analyzed.The effects of different external loads and structural parameters on the tensegrity structure and the two-layer tensioning structure are analyzed,and the change trend in the structural node displacement is analyzed,and the particularity of the two-layer tensegrity structure becomes clearer.Finally,the method of splicing the tensegrity structure is analyzed.Through the force balance between the basic units of the structure,the method of stitching the whole structure of a tensile layer is discussed and the obtained stitching method is applied to the stitching of the two layer tensegrity structure.Then,the stitching structure is modified by changing the α angle and β angle and the radius of the structure is optimized.