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Aiming to find the rotational inertias, the rolling resistance coefficient and the drag coefficient of an electric vehicle, a set of tests was developed based on the speed over time curves in two conditions: free acceleration on a ramp and free deceleration (coast-down) on a flat road. Since the main interest was in knowing the parameters and not only finding the resistance power for different speeds, as is usually the case for a coast-down test, an iterative analysis of both data sets was made. The methodology was validated by testing and analyzing road vehicles, because the values of the parameters were readily available, and by confronting the results of simulations for both types of tests. For the electric vehicle, redundancies and variations were used during testing for validation. The results for the road vehicles were within a margin of up to 10.4% from the reference values.

The competitiveness within the automotive sector increases constantly. Research institutes, universities and manufacturers are commonly trying to discover the new trends and to develop novel technologies. Nevertheless, it is important to understand if a certain technology is worth researching. In order to do that, a state of the art survey is necessary which is usually divided in two main groups: Literature Information and Market Analysis. The literature information regards papers, congress proceedings, books, among other types of formal publication. The market analysis is responsible to gather information within the manufacturers press releases, websites and events, for example. Even though, depending on the technology, those two topics are not enough to reveal the importance of a given technology. Therefore, it is necessary to search the patents database, where it is possible to find the development status of a device.

Although the coil springs are widely used in passengers cars nowadays, the torsion bars still have some application in the competition field, as seen in Formula 1 championship. The objective of this paper is set a comparison between coil springs and torsion bars. The study shows design features, mechanical system involved, the difference of mass, work principle, mathematical methods used and simulation on the two options. The results show which type of spring is most indicated to use in a Formula SAE car using a Pugh Matrix methodology.