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The use of aluminium cast components as the uprights is as old as racing; nevertheless this traditional technology is still a standard on budget racing cars, where the advantages of a steel sheet, welded upright are simply not affordable. It is very well known that cast uprights allow for savings in the case of large production numbers (where “large” should be intended relatively to the racing world). The upright is the component which links the wheel and brake to the rest of the suspension. Being subjected to all the road loads and part of the unsprung mass, it is a fairly critical component. Any failure can lead to an accident; also, it must be as stiff and light as possible for better suspension performance hence roadholding. The paper describes the design of a small single-seater cast upright from the drafting phase to FEM computation to experimental testing. It is a case study rather than an innovative project, but it could be a reference for those involved in a similar design.

One of the hidden aspects of the past Formula One season was the use of indoor road simulators as a mean of speeding up the springing and damping set-up over the race weekend. According to the rumours some teams can perform an indoor set-up optimization overnight by reproducing freshly acquired road profile data. The optimized set-up is then communicated back to the team and tested on-track the day after. The optimization is carried out on a so-called hydraulic four-post rig (or seven-post rig), where a car is shaken at such frequencies and amplitudes to reproduce the same inputs and forces encountered during a typical circuit lap. The Vehicle Dynamics Group of the University of Brescia has recently acquired a four-post rig by Servotest England. The paper aims to describe this facility while future papers will describe the first results obtained in research.

The top Formula 1 and Indycar teams make large use of computer simulation to improve the performance of their cars and make the set-up process quicker on the circuit. The paper aims to present a lap time simulation software dedicated to racing cars. It is based on the background of vehicle dynamics research developed at the University of Brescia, Italy (see [1]). It should be stated that racecar dynamics is strongly non-linear due to the fact that tyres are always very near the limit of adhesion. Moreover this makes the effect of lateral load transfer fundamental for the general balance of the car. Therefore Pacejka's Magic Formula has been used for lateral force/slip while longitudinal force computation is based on the assumption of a maximum longitudinal coefficient of friction μ. This is not only for simplicity but it is also due to lack of available data. The combined case is then based on the so-called “traction circle”.

Quite a lot has been written on active suspension, the topic being suitable for theoretical studies. Unfortunately only a few applications has seen the road and even less went into production; by now very few road cars equipped with a real active suspension system are available on the market, and the interest to this kind of application seems to be reduced, perhaps because of high costs and restrictive regulations applied to the race car world. For this reason this paper presents the results of a study conducted on the vertical dynamics of a two wheel car model with a semi active suspension system, a possible alternative way to a fully active system to considerably improve suspension performance. Here the damping force of each suspension is obtained by modulating its damping factor according to opportune functions of the system state variables. This allows to reach several of the objectives achievable with a fully active suspension, without the need of a big amount of energy.

The time of the “magic touch” approach to race car design is nearly over, and modern engineering techniques are more and more employed in high-level racing. Finite Element Analysis, Computational Fluid Dynamics, Vehicle Dynamics are some of the computer-aided methods which are being successfully applied to improve engine performance, aerodynamics, structural effectiveness and driveability. People at the Department of Mechanical Engineering of the University of Brescia have been working on chassis and suspension modeling in co-operation with racing and sports car makers and leading-edge teams since 1989. Current research partners are the FIAT Research Centre (CRF), Dallara Racing Cars, the Scuderia Italia Touring Car Team, and others.