Application Research On Stochastic Loads Identification For Airborne Product Vibration Environment Prediction

Airborne products often suffer severe vibration environment,these external vibration environment will influence the adaptability and reliability of the products.With the continuous improvement of airborne products' performance and quality,to accurately determine the vibration level has become a key technology to solve.Therefore,it is of great theoretical significance and application value to research the vibration environment prediction of airborne products.At present,for modern products,there is a huge deviation between vibration test response and the measured response due to the vibration environment test with military standard,which is unable to meet the increasing performance requirements.Thus,the paper focus on the application research on stochastic load identification for airborne products vibration environment prediction through the analysis of the measured response spectrum.To increase the accuracy of load identification results and solve the ill-posed problem,the improved regularization method and two-step weighted algorithm are proposed in this paper.On one hand,based on the spectral decomposition technique,a new regularization parameter choice method is put forwarded by introducing the regularization method into error analysis,which can improve the identification accuracy.On the other hand,to improve the deficiency of regularization method,a new two-step weighted algorithm is proposed to solve the two problems of traditional algorithm: sensibility of big condition number and unreasonable weight distribution of identification result.Simulation cases are given to verify the reliability and applicability of the two kinds of method.Some methods are proposed to improve the identification precision by analyzing the factors that influence the accuracy and stability,which provides theoretical support to vibration environment prediction.By means of the proposed improved regularization and two step weighted method,the practical environment prediction method is put forward through the research on stochastic loads identification for airborne product vibration environment prediction,which could be a reference for military standard...