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The Formula SAE and Formula Student competitions, held every year in the USA and UK, challenge teams of engineering students to design and build a small single-seater racing car. The University of Leeds has entered teams into these competitions for the past four years and has developed an award winning hybrid monocoque chassis design. The design enables a light, stiff and extremely safe chassis to be produced at a reasonable manufacturing cost. A chassis which is torsionally stiff enables a desirable roll moment distribution to be achieved for good handling balance. A chassis which can absorb high energy impacts whilst controlling the rate of deceleration will increase the likelihood of drivers surviving a crash without injury. This paper describes how Finite Element Analysis (FEA) techniques have been used to investigate both the torsional stiffness and crashworthiness of the chassis and how physical materials testing has been used to ensure the results are accurate.

Considerable effort has gone into modelling the performance of the racing car by engineers in professional motorsport teams. The teams are using progressively more sophisticated quasi-static simulations to model vehicle performance. This allows optimisation of vehicle performance to be achieved in a more cost and time effective manner with a more efficient use of physical testing. Racing cars are driven at the limit of adhesion in the non-linear area of the vehicle's handling performance. Previous simulations have modelled the transient behaviour by approximating it with a quasi-static model which ignores dynamic effects, for example yaw damping. This paper describes a comparison between different cornering modelling strategies, including steady state, quasi-static and transient. The simulation results from the three strategies are compared and evaluated for their ability to model actual racing car behaviour.

It is often quoted that to be able to make a race car handle ‘properly’ by tuning the handling balance, the chassis should have a torsional stiffness of ‘X times the suspension stiffness’ or ‘X times the difference between front and rear suspension stiffness’ [1]. This paper looks at the fundamental issues surrounding chassis stiffness. It discusses why a chassis should be stiff, what increasing the chassis stiffness does to the race engineer's ability to change the handling balance of the car and how much chassis stiffness is required. All the arguments are backed up with a detailed quasi static analysis of the problem. Furthermore, a dynamic analysis of the vehicle's handling using ADAMS Car and ADAMS Flex is performed to verify the effect of chassis stiffness on a race car's handling balance through the simulation of steady state handling manoeuvres.

There are several fundamental design parameters that determine a race car's performance including mass, centre of gravity height, static load distribution, engine power and aerodynamic forces. A sensitivity analysis is performed on these and other parameters to determine their effect on vehicle performance. This is achieved by looking at specific manoeuvres such as straight line acceleration, braking and steady state cornering to determine the relative effect of the respective parameters. The results presented are determined for both the Leeds University Formula SAE car, figure 1, and a typical mid - late 1990's Formula One car. The results further provide an insight into the differences between high speed cars effected by aerodynamics and low speed cars where aerodynamics makes little or no difference to performance. Combining the performance for a set of manoeuvres provides an insight as to how to improve the overall vehicle lap time.

High mobility combat support vehicles are used over the most demanding types of terrain. Key to their sucess is their off-road performance, particularly with respect to their ability to supply front line forces. Several factors limit their off-road performance including the driver's ability to endure the ride. Improving the ride through the use of intelligent suspension systems enables the vehicle to travel quicker over certain types of terrain. Previous research has identified semi-active suspension systems to have considerable potential for improving the performance of CSVs. This paper describes the development of a practical semi-active suspension for use on the DERA 6x6 demonstrator, fig 1. The modelling presented in this paper shows that this technology reduces the accelerations experienced by the driver by typically 15%. This improvement enables the driver to use increased vehicle speeds whilst maintaining the same level of discomfort.