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The aim of this review article is the analysis of the results obtained from the scientific literature concerning all the phases that make up the life cycle of traction batteries for electric vehicles, in order to evaluate the associated environmental impact. In this regard, some scientific articles dealing with LCA studies concerning electric vehicles, with particular reference to batteries, will be examined. The revision of these articles will provide a general framework for the production, use and recycling phases of traction batteries. In particular, different parameters that influence the outcome of the LCA studies will be shown, parameters on which we can then act to improve the environmental impacts of the transition from internal combustion vehicles to electric mobility. These parameters are represented by the chemistry of the battery considered, aspect at the centre of the discussion, by the specific energy and efficiency of the battery pack, by the durability of the latter, but also by other aspects, such as the energy mix considered (both for the production phase, for the use phase and for recharging) and the functional unit chosen for the study, which determines a different approach, related to the analysis of a specific problem or aspect rather than another. Finally, the usefulness of the recycling practice and the related problems will be shown. In fact, the recycling must be perfected according to the battery chemistry in question to obtain benefits and better reduce environmental loads.

In this work, a reliable and effective method to predict the vehicle side-slip angle is given by means of an artificial neural network. It is well known that artificial neural networks are a very powerful modelling tool. They are largely used in many engineering fields to model complex and strongly non-linear systems. For this application, the network has to be as simple as possible in order to work in real-time within built-in applications such as active safety systems. The network has been trained with the data coming from a custom manoeuvre designed in order to keep the method simple and light from the computational point of view. Therefore, a 5-10-1 (input-hidden-output layer) network layout has been used. These aspects allow the network to give a proper estimation despite its simplicity. The proposed methodology has been tested by means of the CarSim® simulation package, which is considered one of the reference tools in the field of vehicle dynamics simulation. To prove the effectiveness of the method, tests have been carried out under different adherence conditions.

This paper provides a comprehensive revision of the working principles and limitations of the mechanical limited-slip differential (LSD), a passive device used to improve traction capabilities and to extend the performance envelope of high-performance road cars, racing and rally cars. The LSD has been in use for decades. However, according to the authors’ experience, its impact on vehicle dynamics appears to be somewhat neglected in the literature and often misunderstood, especially in the semi-pro racing community. Current research on the subject is usually focused on side aspects and/or on modern control applications such as active differentials and torque-vectoring systems. These state-of-the-art technologies still rely on the same principles of the LSD, which should therefore be fully explained. The authors intend to fill this gap by starting with a comprehensive literature review. Then, an intuitive explanation of the impact of limited slip systems on vehicle behaviour is proposed with simple mathematical models and examples to integrate what seems to be missing. The peculiar shape of the torque-sensitive LSD working zone on the torque bias diagram is explained to an unprecedented level of detail. Real-world application examples are provided, including data recorded on a single-seater racecar integrated with examples based on a virtual model. [ABSTRACT FROM AUTHOR]

The paper presents an integrated approach to suspension design with educational purposes. A dedicated design tool was created to instruct automotive engineering students in the whole process of suspension design across the various CAE tools involved, from early kinematics studies to CAD, vehicle dynamics simulations and FEM modelling. The tool has given birth to a proven design procedure that the authors would like to share in this paper with focus on the educational side, although suspension kinematics design is not certainly a novel subject in itself. The tool includes geometries like the widely used McPherson strut, complex five-link schemes for high-end road cars, and typical racing car geometries like the so-called push/pull rod systems used on Formula 1 and Le Mans racecars. It has been applied successfully to various projects developed by professionals as well as by students, including the latest three Formula SAE (FSAE) single-seaters of the University of Brescia (Brescia, Italy) team. The paper is structured as follows. The introduction describes the role student design competitions play in higher engineering education, and within the frame of the Automotive Engineering course at UniBS in particular. A selection of relevant bibliography on the topic is listed. The Educational scenario section deals with the specific case of the Automotive Engineering course at UniBS and the requirements posed by student competitions, also in the frame of the Dublin Descriptors, and shows how suspension design can play a pivot role in a FSAE project. The A tool for suspension kinematics: requirements, description, solution section presents the software tool in itself. The math underlying the user interface is outlined. Finally, the integration features towards other CAE tools are presented with the related advantages. [ABSTRACT FROM AUTHOR]

Race car performance is strongly affected by aerodynamics. Due to downforce generated by the vehicle floor (i.e. diffuser), vehicle ride heights are key parameters to improve performance, and the coupling of aerodynamics and suspension is one of the key points of race car setting. This work focuses on the suspension and aerodynamic coupling from the vertical dynamics point of view. Besides road holding performance, for race cars, aerodynamic performance and stability are major factors. Downforce decreases laptime (the main performance target) but pitch instability is a non-desired effect that can happen in high downforce race cars. A new vertical dynamic performance index is proposed through the use of simulation to improve aerodynamic performance and understand the pitch instability phenomenon. This new index uses all relevant vehicle nonlinearities related to vertical dynamics and can handle a specific track profile and vehicle speed range, allowing the analysis be conducted according to a circuit specification. A previously validated Formula 3 car model was used as an example. [ABSTRACT FROM AUTHOR]

This work analyses the effect of friction in suspension components on a race car vertical dynamics. It is a matter of fact that race cars aim at maximising their performance, focusing the attention mostly on aerodynamics and suspension tuning: suspension vertical and rolling stiffness and damping are parameters to be taken into account for an optimal setup. Furthermore, friction in suspension components must not be ignored. After a test session carried out with a F4 on a Four Poster rig, friction was detected on the front suspension. The real data gathered allow the validation of an analytical model with friction, confirming that its influence is relevant for low frequency values closed to the car pitch natural frequency. Finally, some setup proposals are presented to describe what should be done on actual race cars in order to correct vehicle behaviour when friction occurs. [ABSTRACT FROM PUBLISHER]