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A stationary model of a car air conditioning system was developed to evaluate refrigerant, mechanical power and all the fluid properties along the circuit. The model requires only the characteristics of the constituents, which are normally available from suppliers. This approach enables estimation of system performance with satisfactory accuracy, already during the design approach, and allows to determine the most appropriate components in order to meet target requirements with a satisfactory balance of the refrigerant circuit.

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 attention to the perceived quality, e.g. the quality as it is evaluated by the final customer, is becoming more and more important for the car makers. The paper will describe how such aspects of handling and steering system feel may become manageable by an engineering process, through some fundamental steps: definition of measurable performance for the subjective aspects; identification of the target values for such aspects coherent with product positioning; deployment of such overall values generally fixed at vehicle level into functional requirements for the different subsystems and design specifications (sub targets level quantities). This new approach at car advanced design represents an evolution of the traditional one based on some general criteria and experienced designers; it has the aims of reducing time to market and guaranteeing a “customer oriented handwriting” in handling behaviour and steering feel.

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.

One of the objectives of the Atena project was the definition of methods for the predictive evaluation of the environmental impact of different types of vehicles used in an urban scenario. The target is to obtain a methodology that allows the decision maker to verify in simulation the effects of possible measures like the law enforcement to the access restrictions or vehicle fleet composition. The main obstacle is the realization and managing of real driving cycles in order to overtake the limits derived from the utilization of typical cycles (i.e., ECE + EUDC) or the simple consideration of average speed. The starting point is a digital representation of the urban network where all the roads are represented with one or more arcs and for all these arcs are available an estimation of the traffic variables like the vehicle flow (vehicles per hour) or the average speed (kph). Every arc is described in terms of traffic parameters like the type of road (i.e., highway, district road).

One of the way for improving environmental performances of car propulsion system is the adoption of hybrid systems where the internal combustion engine (ICE) is coupled or temporary overtaken by an electric motor. The reference prototype of this article is the FIAT Multipla Hybrid where are possible three functional modes: Pure Electric mode, Serial Hybrid and Parallel Hybrid. Particularly it was approached the torque splitting algorithm applied to the parallel hybrid one; the work was first tested in simulation, after implemented in the electronic control units and finally tested on the field using the test bench of the 10 hybrid vehicles that belongs to the Atena Project [1].

The importance of the numerical simulation and testing techniques for the software specifications development of on-board automotive systems design is the paper main issue. In order to promote flexible and rapid procedures improving software specifications, new methodologies are necessary. The proposed procedure is based on the design, simulation, validation, software compiling and rapid prototyping algorithms concerning management strategies of automotive electronic systems. The new feature of this methodology is provided by the comparison between two prototyping environment outputs: rapid prototyping tool outputs represented by strategies running in DSpace® using powerful microprocessors and CPU outputs characterized by limited calculation resources of an almost real one.

This paper describes the development of an electrical compressor-driven air conditioning system for automotive applications. The system uses the thermal properties of reversible metal hydride alloys, which are retained within advanced-design hydride heat exchangers. Calculations on system performance predict high energy efficiency in a package of competitive size and cost. A proof-of-principle prototype has been constructed and bench tested. Measurements from initial tests confirm the excellent performance potential of this system. A study about on-board integration concludes that the system can be installed on a car and can provide all HVAC traditional functions.

In recent years, car manufacturers have been shifting their efforts towards improving quality of interior noise, rather than simply reducing noise levels. One of the most important issues, which is today widely accepted, is that noise contains information. Slamming noise should warn us that doors are safely closed, control panel pushbutton “clicks” inform us about the correct turning on of devices, etc.. One of the acoustic researchers' task is therefore to modify the original noise to emphasize quality of information and to reduce annoying components. For these reasons, it is very important to affect noise timbre, by investigating the relationships between mechanical and acoustical parameters. In this paper we describe a workstation (which we have called N.O.T.E.: Noise Optimizator for Thermal Engine) for intake and exhaust system noise synthesis, that integrates an acoustical simulation code with a synthesizer.

The AICC is an assisting system for controlling relative speed and distance between two vehicles in the same lane. The AICC system may be considered as an extension of a traditional cruise control, not only keeping a fixed speed of the vehicle, but correcting it also to that of a slower one ahead. The main objective of this paper is to illustrate the design of the intelligent cruise control system involving the automatic control of throttle position and braking systems. There is much evidence nowadays that fuzzy approaches to real problems, where the linear control theory fails or can't provide an available and robust design solution, are often the best alternative to more familiar schemes.