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This paper deals with the analysis of a complete axle of a passenger car, which shows brake squeal in test runs. The complete brake system including the parts of the corner is studied with two different Finite Element Analysis programs and their brake squeal calculation algorithms. Thereby significant differences between the results of the two simulations and also the experiments are observed. The used element type and the chosen discretisation level influence largely the simulated contact and thereby the overall results. In order to explain these outcomes, the force distribution and the force vectors between disc and pad are analysed. On the one hand tetrahedral elements cause stiffening of the parts and hence of the contact. On the other hand the effort to create hexahedral elements in daily meshing practice is often omitted due to cost reasons. This trend is enforced by the statement of software vendors.

The present technical article deals with the modeling of dynamic tire forces, which are relevant during interactions of safety relevant Advanced Driver Assistance Systems (ADAS). Special attention has been paid on simple but effective tire modeling of semi-physical type. In previous investigations, experimental validation showed that the well-known first-order Kelvin-Voigt model, described by a spring and damper element, describes good suitability around fixed operation points, but is limited for a wide working range. When aiming to run vehicle dynamics models within a frequency band of excitation up to 8 Hz, these models deliver remarkable deviations from measured tire characteristics. To overcome this limitation, a nonlinear Maxwell spring-damper element was introduced which is qualified to model the dynamic hardening of the elastomer materials of the tire.

Volatile oil prices and increased environmental sensitivity together with political concerns have moved the attention of governments, automobile manufacturers and customers to alternative power trains. From the actual point of view the most promising concepts for future passenger cars are based on the conversion of electrical into mechanical energy. In-wheel motors are an interesting concept towards vehicle electrification that provides also high potentials to improve vehicle dynamics and handling. Beside aspects concerning the electric system (e.g. motor type, energy storage, and control strategy), there are also some open questions related with the mechanical design of in-wheel motor driven vehicles that need to be solved before series production.