High Precision Algorithm of Metal Detector Based on Balance Coil

Metal detector is widely used in food security and industrial manufacture. In order to solve the product effect problem which used only amplitude feature, the dual channel digital detecting algorithm was put forward, based on amplitude and phase information. Also, the balance coil mathematical model was built, and the metal signal feature was deeply analyzed. Through the coordinate orientating, the amplitude and phase information of metal could be exactly extracted, product learning and clustering algorithm could efficiently separate the metal signal and product effect signal. The experiment results showed that the phase information could separate different material metal effectively, cooperated with the amplitude information, the dual channel digital detecting algorithm could extract the metal information accurately and detect the metal with strong product effect.