Research And Application Of Optimal Design Method Based On The Solid Structure Of Combinatorial Optimization Algorithms

In the conventional structural optimization design, design variables are generally considered to be certain, not taking into account their possible uncertainties.That may eventually lead to instability of strcucture performance. So it's necessary to take into account the actural existing variations. Taking some typical components of artillery as the research object, some key technologies of structural robust design method applied in the typical mechanical structures are researched and explored.Firstly, the structural robust design method is studied deeply. A secondary development of optimization algorithm is made based on iSIGHT. The multi-island genetic algorithm and improved Hooke-Jeeves algorithm are combined to propose a six sigma structural robust optimization design method.Secondly,3-D geometry parameterized models of an obturator and a back trail are accomplished.Their statics stiffiness and strength analysis is conducted in ABAQUS to evaluate their structural performances.A structural robust optimization design platform is established in iSIGHT, integrating PRO/E and ABAQUS. The mechanical structure's design -analysis - robust optimization-design is realized.Lastly, a center denseer design of experiment method is proposed to take some more effective explorations to initial design space. In order to get the relationship between responses and design variables, need to do a lot of experiments. That will cost large amounts of resources and time. Therefore, two approximate models, response surface model and Kriging model are studied in thesis. Kriging approximation model is applied to the examples and the computational time is greatly reduced. The transfer operations of multi-island genetic algorithm can keep the diversity of the optimal solution, increase the chance of containing global optimal solution, but its convergence speed is slow. The improved Hooke-Jeeves algorithm can speed up the search in local effectively. The chance of getting global optimal solution is increased the optimization efficiency is improved.The success of robust optimization design to an obturator and a back trail shows that the research and exploration of structural robust design method has a certain applicable value, which can solve some actual problems of the mechanical structure design.