Magnetic Levitation Model (Ball Suspension, with Controller)

For a college project, we need to design and build a magnetic levitation model, whose function is to levitate a metallic ball at a desired height. An electromagnet will be present, whose strength, as determined by the amount of current passing through it, will control the position of the ball, counteracting gravity. There will be sensors to detect the ball position, and amplifiers will be used to use the ball position to make corrections in the current in the electromagnet, thereby providing a stable operation. PFA a possible schematic as reference.