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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.

The first step toward a braking system ‘by wire’ is Electro-Hydraulic Braking System (EHB). The paper describes a method to evaluate through virtual experimentation the actual improvement in vehicle behaviour, from the point of view of both handling and comfort, including also pedal feeling, due to EHB. The first step consisted in modelling the hydraulic unit, comprehensive of sensors. Then it was conceived a control logic devoted to medium-low intensity braking manoeuvres, without ABS intervention, to determine an optimal braking force distribution and pedal feeling depending on the manoeuvre. A failsafe strategy, complete of on board diagnosis, to prevent dangerous system behaviour in the eventuality of a component failure was carried out and tested. Finally, EHB wheel pressure sensors were used to improve both ABS performance, increasing the adherence estimation, and Vehicle Dynamics Control (VDC) performance, through a more precise actuation.

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.

During the past twenty years, crashworthiness of passenger cars in frontal collisions improved significantly, giving a basic contribution to the reduction of accident fatalities and injuries. Nowadays, extensive research are devoted to define a realistic test procedure in order to increase the proximity to road accidents. Asymmetric offset frontal impact against a deformable barrier seems to be the most promising approach in order to reach the goal. The present paper deals with the problem to reproduce the vertical distribution of intrusions in passenger compartments (between floor and facia level) in the correct way. This is a basic condition in order to obtain a deformation pattern similar to those found in real world accidents. A set of tests using Fiat UNO vehicles was performed in order to analyse the effect of different barrier design parameters.