Bionic topology optimization method based on graph method

For taking the advantages of the fractal system in automatically generating graph topological forms，an implicit method was presented to express the structure topology and optimization.This stepped method was firstly based on the results computed by the ground structure method，then a homogenization operation was performed to get the discrete data in the design domain.Through the data got from the previous step to guide the new structure topology direction for the next level from the fractal system，which was similar to the plant growth to get the final structure topology.At last a finite element calculation with parametric modeling was used for the evolution method to get the optimal result.Two cases respectively presented specific implementation process of the optimization system and verified the feasibility of the method.In the first case，an approximate Michell structure was obtained through bionic method under the multi-objective optimization method.In the second case，the buckling load factor of the wing skin was increased by 10.61%，and the mass was reduced by 10.85%，which verified the feasibility of our method to the similar planar structure topology optimization.