Araç süspansiyon sistemlerinin dinamik incelenmesi ve tasarım iyileştirilmesi

Suspension system of a vehicle plays an important role in maintaining the comfort of the passengers by isolating and absorbing road shock from the passenger compartment. For that reason, it is critical to understand the dynamics of the suspension system components and more importantly, the way they interact with each other. In this thesis, the effect of the dynamic, material and dimensional properties of the system components on the performance of the suspension system is analyzed and a general approach is developed to understand the relationship between the design parameters and the suspension vibration isolation performance.The Frequency Response Function (FRF) of the suspension system is obtained through a Finite Element Model (FEM) by using the commercial FE analysis software NASTRAN®. The FEM is used to study the effect of the design parameters of the system components such that the vibration isolation performance of the suspension system can be improved. For this purpose, a structured parametric study, based on techniques from the field of industrial design of experiments is employed to understand the relationship between the design parameters and the suspension vibration isolation performance. A screening study is performed to identify the components that have the highest contribution to the suspension system vibration isolation performance. For each run, the dynamic analysis of the suspension system is performed, the FRFs are constructed and the vibration isolation performance is quantified using several metrics that consider the amount of vibration transmitted through the suspension system. The highest contributors to the vibration isolation performance are identified and preliminary optimization runs are performed to find the optimum values for the critical design parameters. A stochastic approach is also implemented to the above study to consider the variations and uncertainties that arise from a variety of sources like manufacturing processes, external disturbances, and operating conditions.In addition to the above study, material and dimensional properties of particular components of the suspension system are selected as design parameters. A similar procedure is followed to determine an optimum configuration for a better vibration isolation performance. The results are compared using various configurations for sample studies. The results show that the presented approaches can be effectively used to improve the suspension performance by modifying the design parameters of the suspension system.