Search Results

In an automotive suspension, a shock absorber plays a significant role to enhance the vehicle performances, particularly ride comfort and road holding. Because of its important influences on the overall vehicle performances, the understanding of its physical characteristics is essential. Thus, this paper develops a mathematical model of twin-tube shock absorber that is widely used in modern production cars. The model is derived based on a rational polynomial formulation. This formulation generally represents the flow behaviors of fluid across a restriction. Further, simulation results are compared to those obtained from experiments to determine the model accuracy. The result comparison illustrates that the model is able to describe the behavior of shock absorber with slight discrepancies.

The strength of the superstructure of a bus is very critical to the safety of passengers, both in normal operation and in the event of accident. During the normal operation, the structure of the bus is subjected to several loads, which may be induced by its inertia during vehicle maneuvering (i.e. braking and cornering) or by external loads from the road (i.e. crossing over a speed bump). Moreover, there is a substantial possibility that these loads may lead to a structural failure. Hence, it is necessary to determine stresses occurred in the bus's superstructure to ensure its integrity under these driving scenarios. This paper presents techniques implemented to analyze stresses on the superstructure of a newly designed 15-meter long bus subjected to loads previously mentioned using Finite Element Method (FEM). The stress analysis technique used in each scenario is selected based upon the frequency intensity of load excitations and the dynamic responses of the structure.