Analysis And Control Of Automobile Steering System And Dashboard Vibration Performance

The NVH performance of automobile is a very important index in the evaluation of vehicle comfort performance. As a key component which is directly contacted with the driver, the vibration performance of steering wheel is an important index in the evaluation of vehicle comfort performance. Therefore, the research and improvement on the NVH performance of steering system and assembly related are very important for the improvement of vehicle comfort performance. Based on steering system and instrument panel assembly model, this paper studied the vibration characteristics of steering system under the excitation of engine idle speed and random road.First, the finite element models of steering system and instrument panel were established in the finite element software HyperMesh. Then modal analysis was conducted on the finite element models. And the first 8 orders modal parameters were achieved. Then based on the modal parameters, the vibration characteristic of steering system was analyzed combined with different driving source and the conclusion was obtained that the first natural frequency of the system needed to be increased. Then based on the results of modal analysis, the frequency response analysis of the system was conducted under the engine idling excitation, the result of which provided reference for the evaluation of the vibration characteristics.Secondly, for increasing the first natural frequency of the steering system, sensitivity analysis on the first order frequency and total mass to the steering system brackets thickness was conducted, and the sensitive parts were obtained, the thickness of which were established as the design variables. Then in HyperStudy, the Latin hypercube experimental design (LHD) was conducted, of which the response value were first order frequency and total mass, and 100 groups sample points data was obtained. Then approximate mathematics model was established through the Kriging method which was accurate enough for replacing the finite model. At last, Multi-Objective Genetic Algorithm (MOGA) was used as the method to search a group of Pareto Optimum for the optimization.Finally, random response analysis on steering system and instrument panel assembly model was conducted through Radioss solver with the B/C level road as incentive entered. Then the acceleration power spectrum density curves of two nodes which were often held by drivers were obtained. At last, the comfort performance of steering wheel was simply evaluated.