.61 Container Flat Car Body Multi-objective Structure Optimization Design

Multi-objective design optimization of body of 61t container plat vehicle bases on design of light weight for body, and considers the dynamic performance of body simultaneously. There are many defects for conventional multi-objective optimum algorithms to implement the optimization. For multivariable and multi-objective design optimization, there are some shortcomings of Non-dominated Sorting Genetic Algorithm such as high non-dominated sorting computational complexity, lacking reservation of elitism, requiring special share parameterσshare after researching the NSGA. In this paper Non-dominated Sorting Genetic Algorithms-II, namely NSGA-II, is adopted which is the improved algorithm for NSGA. NSGA-II can preserve the multiplicity of solutions using the method of density comparison. Because of comparing the density distance of all the solutions, it doesn't generate the additional parameter likeσshare that is generated in NSGA during calculating process.Because the general merchant software can not implement the optimum objective of multivariable and multi-objective design optimization, the multi-disciplinary optimizing platform iSIGHT is used. The body of 61t container plat vehicle needs FE calculation to obtain the mass of body and the first-order flexural frequency, which is attained under the condition of initial design variables and will be the initial optimizing point for optimization in optimizing platform iSIGHT. The mass of 61t container plat vehicle and the first-order flexural frequency are treaded as objective function, the thickness of each plate is treaded as the design variables and the constraining conditions are strength and stiffness. After optimization, it can obtain a set of Pareto solution to supply valuable information and choice for designer.