Classification of non-magnetic metals based on eddy current array sensors

With the promotion of the circular economy, there has been a growing focus on recycling scrap metal. Eddy current detection offers a new direction for the classification of non-magnetic metals. However, most existing research employs double-coil eddy current sensors, and there is a need to improve the detection range and accuracy. Aiming at the above problems, this paper proposes a classification of non-magnetic metals based on eddy current array sensors, which uses sensors to obtain the mutual inductance trajectory of the metal as it passes through each receiving coil, and uses the phase value of its amplitude peak point for the classification of the metal. The paper discusses the impact of different running trajectories and lift-off heights on the classification accuracy. The experimental findings indicate that compared to the dual-coil sensor, the effective detection range increases by over five times. Moreover, the classification accuracy within the detection range reaches 98.4%.