Robotic Eddy Current Inspection is Non-Destructive Testing (NDT). NDT is required to validate part integrity without causing the part any physical damage. All parts are inspected for surface and subsurface defects using some form of NDT. Eddy Current Inspection (ECI) is one of these disciplines and is used to inspect inaccessible or hard-to-reach surfaces or surfaces where tight defects must be identified and located. It’s an electromagnetic inspection technique that works by inducing an electric current and an alternating magnetic field running around the current (coil) into the part which in turn, generates its own current opposed to that from the coil. The result is called an eddy current or electron flow (i.e., current = voltage/resistance). Part conductivity, wall thickness and surface defects in the part change the eddy current in phase and amplitude and the change is measured as impedance changes in the coil. The allowable change in the part being inspected determines the acceptability of any defects that cause the change. ECI can be used on ferromagnetic and non-ferromagnetic materials. Its limitation is non-conductive materials.