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The paper deals with a method implemented to study braking systems design, modelling components' characteristics through commercial software. It summarizes the potential improvement possible by using modelling techniques in chassis systems design. The first part consisted in producing a passive braking system model. A first validation was carried out on a test bench by using components of different braking systems. Particular attention was devoted to booster modelization both in semi-stationary and dynamic conditions. The second part was callipers, roll-back and thermal phenomena modelization. Finally, it were modelled Anti-lock Braking System (ABS) and Vehicle Dynamics Control (VDC) Hydraulic Units and their integration with control strategies and with vehicle dynamics model.

The aim of this paper is to describe the development and the applications of a mathematical model for the vehicle driveline used to analyze the link between the performances car and vehicle driveability. It's well known that the car driveability depends by the dynamic response of the driveline car, whereas the classic performances depend by the coupling between engine's steady characteristic (torque and power curves) and vehicle's proprieties (weight, rolling resistance, drag coefficient, etc.) carried out by tuning of suitable gear shift ratios. The definition of the link between the driveability and the performances represents a very hard problem because it exceeds the limits in the field of the subjective perception, where the two aspects are themselves overlapped. To describe in analytical way this problem it's been introduced a new metric, where it's possible to evaluate at the same time the vehicle driveability and car performances.

Centro Ricerche Fiat in collaboration with Fiat Auto vehicle test department has developed a numerical-experimental procedure in order to support on-road development and fine tuning of a new car with electric power steering. The integration of an electric power steering model, given by the supplier, in a full vehicle model, in order to evaluate steering feel objective quality indices, has allowed to improve vehicle performance in term of steering feel and reduce on-road development time.

The aim of this paper (which is the continuation of the work presented at the ISATA 2000 International Conference [1]) is to analyse the low frequency driveline torsional vibrations in a vehicle. It is known from many studies and investigations, that the driveline torsional vibrations are mainly responsible of the driver's performance perception and the vehicle's driveability [2, 3, 4]. So many manufacturers use the driveline's response in order to provide their vehicles with characteristics that are specific for the vehicle's segment class and the market. In this regard the vibration's behaviour has been investigated, studying some typical steady and transient vehicle manoeuvres. As a diagnostic guideline for the design's concept development, a driveline simulation model in Matlab/Simulink environment has been implemented. Therefore the basic features has been created to improve a complete vehicle co-simulation, using a engine cycle code and a mechanical driveline model.

The cabin comfort is one of the most competitive issues in the automotive area of business. The thermal comfort and the environmental well-being are fundamental performances that contribute to generate the more general idea of perceived quality. The CRF developed in the past the concept so-called “healthy bubble” that was implemented in the Lancia Dialogos concept car. The passengers are surrounded by an air bubble, created by generating low velocity air flows, that are diffused through the interior panels and components (e.g. dashboard, roof, back of the seats, etc.), and by surfaces temperature control (e.g. carpet, seats, etc.). At present the original idea has generally been accepted, and different solutions to diffuse air and to control surface temperature of vehicle interiors have been proposed by some automotive supplier.

In the last century cars have become almost irreplaceable objects in modern society. There are almost half a billion cars circulating around the world while about thirty years ago there were about half this number. Most experts agree that the goal of a billion isn't so far away. Nevertheless one must consider that car production and use environmental impact has been strongly improved. This is mainly due to a greater consciousness of manufacturers and clients towards environmental effects of high living standards. This work not only points out the state of the art of the actual situation but also focuses on the improvements that can be reached in a near future.