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When driving on roadbed irregularities vehicles are excited to vertical vibrations. In the case of a truck the excitation is transmitted to the frame which not only bears the platform with the payload, but also serves as base for the cab spring suspension. Furthermore, the cab usually accommodates the occupants on spring suspended seats. Both occupants and payload have to be insulated against vibrational load by means of the different suspension systems. The paper deals with the technical development of the vibrational system of the truck up to now, the current trend, and the consequences thereof.

Due to long working hours at the steering wheel of a long haulage truck great attention has to be paid to the driving comfort. The possibilities of passive suspension systems are widely exhausted. It is shown by results of measurements that an active suspension system is well feasible with commercially available hydraulic components, though naturally still to be improved. An apropriate concept is presented including neccessary changes of the existing test vehicle taken from series, sensorics and safety considerations. Also basic features of the control strategy and a first test rig for evaluating the control parameters of the hydraulic system are described.

The different applications of trucks (short-, medium-, long distance haulage, construction site) lead to very different requirements to be met by the brake systems. Concerning transmission the air braking system has great advantages for trucks and has therefore prevailed. On the other hand the design of the brake system must consider the regulations. In Europe common regulations concerning braking systems have been brought out since 1972 and have superseded formerly national standards. So the set up of the braking system mainly with regard to the brake balance is dealt with under consideration of the european braking standards. The influence of braking on handling is very important. Therefore the behaviour of a truck and a tractor/semitrailer is discussed for braking in a straight line and in a turn.