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It is well known that wheels are responsible for a significant amount of the total aerodynamic drag of passenger vehicles. Tyres, and mostly rims, have been the subject of research in the automotive industry for the past years, but their effect and interaction with each other and with the car exterior is still not completely understood. This paper focuses on the use of CFD to study the effects of tyre geometry (tyre profile and tyre tread) on road vehicle aerodynamics. Whenever possible, results of the numerical computations are compared with experiments. More than sixty configurations were simulated. These simulations combined different tyre profiles, treads, rim designs and spoke orientation on two car types: a sedan and a sports wagon. Two tyre geometries were obtained directly from the tyre manufacturer, while a third geometry was obtained from our database and represents a generic tyre which covers different profiles of a given tyre size.

The following paper describes how to measure the global torsional stiffness of a complete car under field-like conditions. All that's needed are lifting devices, two stands of equal height, three glide planes or equivalent, three scales and two inclinometers, a spirit level, some pieces of aluminum and a glue gun. The results from four measured cars are presented and a comparison is made with values obtained with laboratory equipment and data from manufacturers. The method is a fast and economic means to find the most interesting cars that then can be selected for measurement by traditional methods, giving the stiffness as a function of the vehicles long axis, and thus minimizes the cost of benchmarking. Time for measuring one car with all equipment readily available and with personnel having some experience of the method is about two hours. Only the sway bars have to be disconnected. Absolutely no damage to the measured car means that rented cars can be used.

Today automotive system suppliers develop more-or-less independent systems, such as brake, power steering and suspension systems. In the future, car manufacturers like Volvo will build up vehicle control systems combining their own algorithms with algorithms provided by automotive system suppliers. Standardization of interfaces to actuators, sensors and functions is an important enabler for this vision and will have major consequences for functionality, prices and lead times, and thus affects both vehicle manufacturers and automotive suppliers. The investigation of the level of appropriate interfaces, as part of the European BRAKE project, is described here. Potential problems and consequences are discussed from both a technical and a business perspective. This paper provides a background on BRAKE and on the functional decomposition upon which the interface definitions are based. Finally, the interface definitions for brake system functionality are given.

A new in-vehicle communication concept for CAN networks has been developed, taking into account recent findings from real-time research. The concept is characterized by three impo features: (i) Ability to guarantee the real-time performance of the network already at the design stage, thus significantly reducing the need for testing; (ii) Built-in flexibility enabling the vehicle manufacturer to upgrade the network in the pre-production phase of a project as well as in the aftermarket; (iii) Low use of available resources, thus saving cost compared to other solutions. The concept is successfully used in all larger Volvo cars from model year 1999.

To give the customer an immediate impression of quality several of criteria must be fulfilled such as styling, paint finish and fitting of outer panels/closures. Therefore, higher demands on geometrical quality e.g. stability for both exterior and interior are needed. The structural part of the car body is the key element for success. Beside the visual impression, lack of noise and vibrations during driving can convince a potential buyer to become an actual customer. To achieve this, car manufacturers have to draw up an overall strategy in combination with proper working methods to be able to guarantee a stable geometrical output throughout the entire development process and during series production over the lifetime of the vehicle. On a simultaneous engineering basis, the OEM, the system/component- and the process suppliers (for the industrial system from press shop to final assembly) have to adopt a common measurement strategy.