348 / 2021-07-07 21:18:51

Research of random excitation identification for stochastic structures based on whole vehicle road noise

Vehicle road noise,random dynamic loads identification,uncertain

Noise and vibration control

In view of the characteristic of pseudo excitation and effects of the regularization parameter on the residual norm and solution norm, a novel modified regularization method is proposed to solve the ill-posed problem and mitigate the error propagation of random dynamic loads identification. Compared with Moore-Penrose pseudo inverse and Tikhonov regularization methods that are sensitive to the selection of measurement locations, the proposed modified regularization method improves the accuracy and stability of random load identification, effectively reduces the huge identification error in the low frequency range, prevent the overly regularization in the medium-high frequency range, and can always match the actual excitations from low to high frequency domains. Furthermore, the matrix perturbation method is combined with the modified regularization method to analyze the multisource loads acting on the uncertain structure. Several practical engineering examples are conducted to demonstrate that the lower and upper bounds of identified forces can be obtained, which clearly validates the effectiveness and feasibility of the proposed methods in the application of complicated structures. Additionally, based on the proposed random excitation identification method, a platform for the spindle load identification and vehicle road noise forward development is established, which combines simulation with test. This platform breaks through the predicament of unpredictable road noise due to the load deficiency in the early stage of vehicle development.