The Impact Of Tyre Characteristics On The Braking And Steering Performance Of Commercial Vehicles

The tyre, as a link between vehicle and road, is an essential component to which great attention is paid when new vehicle concepts are being developed. The main criteria required of commercial vehicles are economy, safety and comfort- Increasing importance, as far as handling of commercial vehicles is concerned, is attached to the frictional behaviour of tyres. The influence of typical parameters, such as wheel load, road speed, inflation pressures of tyres, tyre tread depth and road surface as well as the effect of the scattering of the coefficient of adhesion of the different tyre makes are shown by means of steady-state and dynamic measurements. The directional control behaviour of a heavy commercial vehicle is analyzed with the aid of a simulation system developed by Mercedes-Benz. This includes computer-controlled test stands for tyres, brakes and axle kinematics as well as programmes for simulating the dynamics of a vehicle making use of the measured characteristics. In order to compare fluctuations in vehicle handling as a result of varying the tyre parameters, ISO test procedures, such as “Steady State Circular Test”, “Braking in a Turn” and “Lateral Transient Response Test”, are applied and the results obtained are commented on.