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The automobile industry strives to develop high-quality vehicles quickly that fulfill the buyer’s needs and stand out within the competition. Full utilization of simulation and Computer-Aided Engineering (CAE) tools can empower quick assessment of different vehicle concepts and setups without building physical models. Vehicle execution assessment is critical in the vehicle development process, requiring exact vehicle steering system models. The effect of steering system stiffness is vital for vehicle handling, stability, and steering performance studies. The overall steering stiffness is usually not modeled accurately. Usually, torsion bar stiffness alone is considered in the modeling. The modeling of overall steering stiffness along with torsion bar stiffness is studied in this paper. Another major contributing factor to steering performance is steering friction. The steering friction is also often not considered properly.

There is a growing need for the accurate Computer Aided Engineering (CAE) models for vehicle performance evaluation. The reduced product development time and complexity of the vehicle evaluation demands accurate prediction with CAE models. Vehicle dynamics performance evaluation is very critical in vehicle development process, which require very accurate vehicle and tire models. The tire characteristics are represented as mathematical, physics based and empirical models. There are different types of tire models exist like Fiala, PAC, SWIFT and FTire etc, which can be used for vehicle handling, ride and steering performance evaluation. There is a need to study and understand these tire models before applying to specific vehicle dynamic performance. There is a challenge to get the tire models as tire modeling require lot of tests and time consuming.

A critical requirement for product design and development is meeting vehicle dynamic performance. Customers changing needs puts tremendous pressure on automotive businesses to launch new vehicles within short durations of time. This makes it mandatory to have a wide-ranging virtual simulation and vigorous validation process to provide best in class ride and handling performance of vehicles. Physical testing of prototypes is the most time-consuming activity, so there is a need of front loading to substitute these requirements at the initial stage of the development cycle. This paper summarizes the overall process for front loading vehicle dynamics requirements during basic architecture definition using virtual simulation. Basic dimensions, CG, weight distribution and steer angle of the new vehicle are derived using concept calculations based on benchmark vehicles. Vehicle dynamics trials are then done for the benchmark vehicles.