Research On Uncertainty Theory And Application To Design Of Mechanical Products

With the continuous improvement of our manufacturing level, to enhance the competitiveness of mechanical products, not only to meet the economic requirements of products, product cost as low as possible ,but also to meet robustness and reliability requirements of mechanical products, so to propose new requirements for mechanical product conceptual design. Because there are several uncertain factors in the design process of mechanical products, many without fully considering the case of uncertainty, the robustness and reliability of the mechanical design of products will significantly reduce, and in engineering, the failure rate of mechanical products will greatly increase, resulting in greatly economic losses. Therefore, in the design of mechanical products, to improve the robustness and reliability of mechanical products and meet quality requirements and economic requirements, so filling the uncertainty in multidisciplinary design optimization theory into the conceptual design of mechanical products, will be able to meet the above requirements.First of all, access to a lot of information on the application study of uncertainty theory in mechanical product, to summarize on the country for research on the uncertainty theory ,and the concepts of uncertainty theory, to research on uncertainty uncertainty modeling, reliability, constraint is equivalent to deal with uncertainty and uncertainty analysis methods ,to be basis in solving the gantry crane hoisting mechanism the uncertainty design optimization.Secondly, the design goal for the modeling features, combined with uniform design ideas, based on uniform design of the proposed response surface method. In this method, uniform design to reduce test times and reduce system analysis model calculation of the cost of training samples, improve computing speed, speed up the model convergence. An example test showed that the above modeling method to improve approximation accuracy of the model in improving the approximate response surface modeling and speed up the convergence of viable and effective.Again, through the concurrent subspace optimization algorithm for the induction process and proposed an improved response surface-based concurrent subspace optimization of uncertainty, the uncertainty of design optimization will be integrated in the improvement of response surface-based sub-parallel spatial uncertainty optimization process, design variables and system parameters on the uncertainty analysis, design optimization process, consider the overall robustness and reliability of the program, to achieve acceptable computational cost and robustness under the access to meet the reliability requirements of the optimal solution, and then tested by numerical examples show that the method is feasible and effective.Finally, the crane hoisting mechanism of the overall design discipline model, response surface-based Concurrent Subspace uncertainty for the method, program crane hoisting mechanism for the uncertainty of the overall design optimization. Crane hoisting mechanism to establish the overall design optimization model uncertainty, crane hoisting mechanism according to the design requirements, hoisting mechanism on the overall optimization of the uncertainty model, the influence of design variables constrain the set of parameters, test results show that the method effective and feasible.There is a certain significance that uncertainty theory approach to its conceptual design of mechanical products, to improve the robustness and reliability, to reduce mechanical products in the practical application failure rate.