Almost all mtbs (and eddy current brakes) are equipped with electromagnets, which are responsible for the magnetic attraction between the braking system and the rail. The magnetic attraction is a major performing index of electromagnetic brakes. Therefore, this subtopic is devoted to a better understanding of the effects of the magnetic attraction of a pole shoe moving over a rail. Influences of motion-induced eddy currents on the spatial distortion of the magnetic field and consequently on the magnetic attraction are studied, considering different pole shoe velocities (all spatial directions), geometries (track and pole shoe), material, surface topology (rail corrugations), and additional layers (e.g. pick-up weldings, contamination, friction modifiers). The involved new case of running over switches and crossings will be used to analyse to which extent the electromagnetic forces contribute to the dynamic behaviour of the pole shoe at fast 3D geometric transitions, including large interruptions (with respect to the pole shoe's dimensions), different conducting bodies and materials.

The general aims of this research topic are:

• Identification of relevant influences on the magnetic attraction of the pole shoe on a straight rail considering the motion of the mechanical system.
• Accounting for varying 3D geometry and material of the rail, as it is observed at switches and crossings; the influence of altered pole shoe geometry is considered as well.
• Gaining insight into the complex dynamic behaviour of the electromagnetic-mechanical system of one pole shoe and the rail when the track diverges, typical for switches and crossings.
• Understanding the impact of additional layers consisting of contaminants (e.g. leaves, dust, grease, and moisture) and friction modifiers (e.g. sand or Sandite), and pick-up weldings on the magnetic attraction between pole shoe and rail.