Friction is the resistance of a body against movement on a base. Static friction means that a body remains at rest under the action of a force. If a limit value is exceeded, the body begins to move on the base, resulting in dynamic friction. Self-excited friction oscillations, also known as slip–stick phenomenon, occur if the static friction is significantly higher than the dynamic friction.

The tribological system in TM 260.04 allows a clear demonstration of the transition from static to dynamic friction and the occurrence of friction oscillations. The experimental unit contains a rotating stainless-steel disk and a loosely fitting friction ring as the friction pair. The contact force between the friction partners can be adjusted gradually up to a maximum of 40 N by means of weights.
A tension spring prevents the friction ring from rotating. The necessary holding force is measured by a force sensor.

The TM 260 drive unit is required in order to conduct experiments. The experimental unit is mounted quickly and easily on the frame of the drive unit with quick-action chucks. The disk is driven by a clampable coupling between drive unit and gear unit. The display and control unit of the drive unit shows frictional force and speed and allows the continuous adjustment of the speed.

The frictional force and the coefficient of friction can be determined in experiments. The frictional forces are measured by a force sensor. Friction rings made of different materials are included in the scope of delivery to study different friction pairings.