REPULSIVE MAGNETIC LEVITATION

Its fascinating to see an object floating in mid air without any direct physical contact. Me, Ruchik, Nagasai and Hemant wanted to build a system that can levitate a Neodymium magnet repulsively in air. One way to do it is using attractive magnetic levitation and other is using repulsive magnetic levitation. Attractive magnetic levitation is easy to achieve but repulsive magnetic levitation is hard to achieve because of the complexity involved in feedback loop. A robust PD feedback control loop is necessary for stable magnetic levitation. In this setup above, the position of the magnet is sensed using hall-effect sensor. This position feedback is used to correct for errors. The hall-effect value is amplified differentiated and applied to the electromagnetic coils to achieve stability. In the setup shown we have used 4 coils, 4 independent PD loops and 4 hall effect sensors.