Structure and fields of application
The RepTiL (Realistic Pattern Mechanics in Lab) is a hybrid test bench that enables friction coefficient tests to be carried out on tire tread blocks on different road surfaces and under various climatic conditions. The RepTiL offers the possibility of simulating and measuring the rolling motion of a single passenger car tire tread block. The measurements enable comparative predictions and the generation of hypotheses about tire performance and the behavior of the individual tire tread block when sliding on a surface.
The RepTiL reproduces the rolling motion of a tire tread block on a tire with three degrees of freedom. A vertical and rotational movement of the sample holder simulates the freely rolling wheel using two independently controllable servo motors. The third degree of freedom for describing slip is achieved by a horizontal displacement of the track, which is controlled by an additional servo motor.
The vehicle speed can be adjusted between v = 0 mm/s and v = 1000 mm/s with variable slip. A normal force of up to 1000 N can be applied to the sample holder. The sliding distance, speed, and load can thus be adjusted according to the specifications of a real tire. Four piezoelectric force transducers in the sample holder can measure the normal force and the frictional forces in the contact plane. In addition, the vertical and rotational movements are recorded during the tests. The test bench is set up in a climate chamber in which temperatures from -20 to +40 °C can be achieved. This enables tests to be carried out under summer and winter conditions. The RepTiL enables friction coefficient investigations on road surfaces made of, for example, asphalt, glass, aluminum, ice, and snow. For certain surfaces, the deformation of the tire tread block can be recorded with a high-speed camera and included in the analysis process of the measurements.
