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Tires of modern commercial vehicles must meet a specific requirement profile, containing the economic aspects, ride comfort and driving safety, as well. These three primary criteria are discussed in this paper, whereby emphasis is placed on the force transmission behavior of commercial vehicle tires regarded as a variable directly associated to driving safety. At the same time, the influence of distinct parameters such as wheel load, road speed, tire inflation pressure, tread depth and coefficient of adhesion between tire and road on the lateral and braking force behavior is illustrated using steady state and dynamic measurements. They were carried out on real roads using a specially prepared mobile tire dynamometer, but on an indoor drum-type tire test stand, as well. In addition to the above mentioned parameter variations the differences of the results on account of the test method are analysed.

In particular on heavy duty commercial vehicles, the continuous braking systems “engine braking system” and “retarder”, which are independent of the service braking system, are installed to handle the continuous braking load on downhill stretches. These systems are also used to reduce lining wear and thermal loads of the service braking system. Exhaust braking systems are the most widely used form of engine braking systems. The current state-of-the-art in retarders is represented by two basic concepts, the electrodynamic retarder and the hydrodynamic retarder. A performance comparison of the different systems shows that low mountain descending speeds are the domain of engine braking systems, whereas retarders are more effective for medium and high descending speeds. The electrodynamic retarder is more favourable for lower road speeds, while the hydrodynamic retarder develops its effectiveness during higher downhill speeds.

The consequent means towards improved enhancement of the safety of commercial vehicles will in future times require more and more electronic intelligence, in case a distinct optimization of the systems will not be possible with conventional means. In forefront, endeavours are aimed at the improvements of the functions of the system in regard to driving safety, as well as driver stress relief at lowest possible costs, in order to increase the total cost effectiveness of commercial vehicles. Starting with currently implemented electronic systems up to systems now under development, a continuous development of standalone electronics up to integrated electronic compounding is the current trend. This trend shows advantages of reduced wiring and the number of sensors while it increases the function at the same time.

The simulation of the driving performance of motor vehicles offers the possibility of analyzing the behavior of new commercial vehicles or new systems to be integrated into the vehicle, already before the stage of the first prototypes. Thus, simulation technology may contribute to shorten the time and costs needed for the development of new vehicles and new vehicle systems. As an example, this contribution describes the simulation of a commercial vehicle with adaptive suspension elements. The simulations were used to coarse-tune the suspension elements before installation and fine-tuning them in a prototype vehicle, and to define and optimize the control strategies of electronically controlled suspension systems. A comparison between the costs of the simulation and estimated costs of corresponding field tests substantiates the economical benefits of the simulation.