Focusing on the topology model of epicyclic gear trains in the excessive abstraction and the pursuit of extreme divergence

the innovation and optimization design on wheel system failed to achieve the expected results.All kinds of possible configurations of complex topology model are achieved from the topology combination theory based on topological unit.However

due to the complex topologies symbol meaning uncertainty and element meaning still diverge

so between the topology and simulation gear trains still not one to one relationship.To solve this problem

the topology evolution theory is proposed after the combination theory and establishing the evolution rules

the qualitative evolution for the topology elements is realized

the conversion process from combination-topology to assembly-topology is achieved

the purpose of search for all possible topologies are realized.Finally

epicyclic automatic assembly is realized rely on the extract information of assembly-topology which are obtained by computer.The result shows that methods are reasonable and feasible.Through these theories and methods

the foundation of simulation-experiment environment for trains mechanism innovation and optimization design is established

the new ideas for modeling analysis are provided.