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Vehicle dynamics development relies on subjective assessments (SA), which is a resource-intensive procedure requiring both expert drivers and vehicles. Furthermore, development projects becoming shorter and more complex, and increasing demands on quality require higher efficiency. Most research in this area has focused on moving from physical to virtual testing. However, SA remains the central method. Less attention has been given to provide better tools for the SA process itself. One promising approach is to introduce computer-tablets to aid data collection, which has proven to be useful in medical studies. Simple software solutions can eliminate the need to transcribe data and generate more flexible and better maintainable questionnaires. Tablets’ technical features envision promising enhancements of SA, which also enable better correlations to objective metrics, a requirement to improve CAE evaluations.

The behaviour of the tyre plays an important role in controlling the horizontal motion of the vehicle. In vehicle dynamics studies, a good representation of tyre behaviour is therefore a necessity. A series of tyre measurements have been carried out on the road in stationary conditions. The data obtained have been represented by mathematical expressions on the basis of a formula. The coefficients in the formula represent some of the typifying quantities of the tyre and the formula is capable of describing all characteristics of side force, brake force and self aligning torque with great accuracy. The behaviour of the tyre during combined cornering and braking has successfully been described by a model which makes use of the obtained mathematical expressions and some tyre-modelling theory. The side force characteristic governs the behaviour in lateral direction and the brake force characteristic in longitudinal direction.

A new way of representing tyre data obtained from measurements in pure cornering and pure braking conditions has been developed in order to further improve the Dynamic Safety of vehicles. The method makes use of a formula with coefficients which describe some of the typifying quantities of a tyre, such as slip stiffnesses at zero slip and force and torque peak values. The formula is capable of describing the characteristics of side force, brake force and self aligning torque with great accuracy. This mathematical representation is limited to steady-state conditions during either pure cornering or pure braking and forms the basis for a model describing tyre behaviour during combined braking and cornering.