Rotating Electromagnetic System for Railway Track Crack Detection Michele Buonsanti 1,a , Giovanni Leonardi 1,b , Giuseppe Megali 1,c and Francesco Scopelliti 1,d 1 Mecanics and Materials Department, University “Mediterranea” of Reggio Calabria, Via Graziella Feo di Vito, I-89060 Reggio Calabria (Italy) a michele.buonsanti@unirc.it, b giovanni.leonardi@unirc.it, c giuseppe.megali@unirc.it, d francesco.scopelliti@unirc.it Keywords: Fatigue fracture, Fracture dynamics, Non-Destructive Testing, Rotating Magnetic Field, FEM, Rail Maintenance. Abstract. The aim of this paper is to provide an alternative methodology, high reliability, in order to monitor, exploiting non-invasive techniques, railway track. In this particular case study, the presence of structural defects is assessed through an innovative system. The proposed approach provides the use of rotating magnetic field. Within this framework, the Eddy Current Techniques (ECTs) have greatly increased their importance for their capacity to detect the magnetic field variations caused by the presence of material alterations. Whilst the researches in this field propose various solutions to the detection of flaws (in surface and subsurface), a still open problem concerns the difficult detection of defects due to the geometrical complexity of the structure and the particular orientations of the crack. Particularly, this contribution proposes an approach based on Finite Element (Finite Element Method, FEM) for the modeling of railway tracks, in order to obtain a rapid and precise assessment about their integrity. Introduction The problem of control and maintenance of railway track is important for the modern management of railways because it implies a high cost and it has consequences on the safety levels. Moreover, a large part of the infrastructure was designed and built for an use that was much lower than today. Just think about the sharp increase of the axle loads and trains number, length and speed. This implies an increase of the stress which may cause a higher speed evolution of the phenomena of degradation. However, the time between the damage detection, the scheduling/planning of maintenance interventions and the resolution of the problem, was reduced to the point to require a reformulation of programming methodologies and control. In this perspective analyses using non-invasive techniques (Non Destructive Testing, NDT) had a strong expansion. The most common defects in railway are Rolling Contact Fatigue (RCF) cracks of rail [1]. These cracks are governed by a number of factors including environmental conditions, rail and wheel profiles, track curvatures, grades, lubrication practices, rail metallurgy, vehicle characteristics, track geometry errors, and rail grinding practices [2]. They all play a role in the formation of RCF and - universally - can be used to control and minimize RCF. For this kind of diagnosis, NDT technologies assure the required quality and accuracy. This paper proposes the development of NDT approach, which uses remote field Eddy Currents (ECs) induced by a Rotating Magnetic Field (RMF). In particular, in EC Techniques (ECTs), the variation of magnetic field H, induced by the variation of ECs, is considered to detect the rail flaws. The normal component of H, i.e. H ┴ , is measured by suitable sensors, since it is not influenced by the exciting coils. But, if the crack orientation is vertical to the sensor longitudinal direction, the inspection could be insensitive to the defect presence. Therefore, a methodology of inspection insensitive to crack direction could be very useful in order to improve the quality of the analysis. In this way, a RMF sensor can detect defects through effects exercised in both the x-axis and y-axis. In this way we proposed the use of a system able to generate a RMF, rotating perpendicularly to the inspection plan. Its major advantage is that it allows detection of defects, regardless of their shape and