Bài viết tiến hành phân tích đặc trưng ngẫu nhiên tần số dao động của mô hình ô tô bằng cách tiếp cận phi thống kê thông qua phương trình dao động của mô hình ô tô có bốn bậc tự do được thiết lập bằng cách sử dụng phương trình Lagrange. | Transport and Communications Science Journal Vol 72 Issue 2 02 2021 226-237 Transport and Communications Science Journal VARIABLITITY IN FREQUENCIES OF VEHICLE VIBRATION ANLYSIS WITH MUILTIPLE RANDOM VARIABLES Nguyen Van Thuan1 Ta Duy Hien2 3 1 Nha Trang University No 2 Nguyen Dinh Chieu Street Khanh Hoa Vietnam 2 University of Transport and Communications No 3 Cau Giay Street Hanoi Vietnam 3 Research and Application Center for Technology in Civil Engineering University of Transport and Communications Hanoi Vietnam ARTICLE INFO TYPE Research Article Received 21 9 2020 Revised 6 2 2021 Accepted 8 2 2021 Published online 15 2 2021 https Corresponding author Email thuannv@ Tel 0393007896 Abstract. Vehicle dynamic analysis with random parameters has been a hot research topic for many years because of its important role in ride comport vehicle safety and overall vehicle performance. This study deal with the response variability in the natural frequency of vehicle by non-statistic approach. A four degree of freedom car vehicle model is used to study the vibration response of vehicles with uncertain parameters. The governing equations for the natural frequency of vehicle are derived from Lagrange equations. The randomness in mass density and stiffness of springs are assumed to be a Gaussian random variables. Mass matrix and stiffness matrix can be perturbed with respect to the mean of the system random variables. The variance of eigenvalue and mean of eigenvalue are obtained by zeroth-order and first-order of approximated perturbation equation. The stochastic analysis of vehicle vibration is performed in conjunction with Monte Carlo simulation MCS in order to show the legitimacy of the perturbation solutions. Numerical examples are given in detail. Some results obtained by the non-statistic approach and those from the Monte Carlo simulation approach show a good agreement. Keywords non-statistic approach vehicle vibration natural .
