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Tires will be protagonists in the new European regulations for safety and fuel economy: in 2012 a tire pressure monitoring system will be mandatory for all new vehicles, enabling as natural consequence the development of the so called “intelligent tire”, able to capture all the relevant information of the contact between the road surface and the rubber, a starting point for new functions development to improve safety and reduce fuel consumption of all vehicles. A description of the methodologies that can be used to extract features from the tires, based on the experience of the development of Cyber Tyre, a high performance sensorized tire, is included in this work; comparison with the same information gained thorough ordinary sensors are provided too. The paper also presents some interesting examples of how data, coming from Cyber Tyres, can be exploited to improve the safety margins of a vehicle, preventing the critical operating condition represented by hydroplaning.

Transport system safety is clearly one of the most important social problems and involves a lot of items, such as road, tyre and vehicle design. VERT Consortium (EC funded Project BRPR-CT97-0461), including ten partners from six different European countries, has faced this problem in the last three years implementing in ADAMS Environment a full vehicle model focused on tyre/road interaction in presence of water, snow and ice. Such a model has been finally exploited in order to detect the most dangerous situations and to define guidelines for the optimised design of new “safer” products (tyres, vehicles and roads). This paper presents a general overview of VERT activities and achievements.

A new Tyre Model suitable for Tyre Dynamic Representation on uneven road and in general high-frequency handling excitations has been developed in a multi-body code. The tyre representation is both empirical and physical: contact forces between contact patch and road are achieved from numerical Pacejka formulation but applied to a physical structure representation instead of to a simple spring-damper element. Such a physical tyre model enables the simulation of the dynamics up to 100 Hz and vibration due to high frequency handling manoeuvre or on uneven road contact excitation. Validations with experimental results are of course included both for tyre tests on suitable testrigs and for full vehicle manoeuvres.

This paper introduces and discusses a new 2D physical model which has been developed and validated in order to study and optimize the handling behavior of the tire. It can be divided into two parts, the structural model and the contact area model. The parameters, that are function of the vertical load, are identified or calculated by comparison with the results provided by 3D finite element models. The input data for the identification procedure consist of a set of frequency responses performed on the finite element model. A second set of simulations on the 3D model of the tread pattern gives the characteristics of the contact model. Once built the 2D model it is easy to carry out both steady state and transient analysis. The steady state analysis returns the cornering carpet, in terms of lateral force and self-aligning moment as function of the cornering angle. The transient analysis allows the evaluation of the relaxation length and dynamic characteristics.