In electromagnetic attraction type of magnetic levitation system, the intensity of the force of attraction depends on the magnitude of the current through the coil. The coil hence must be designed in such a way that it does not get heated while producing the required force. Here Finite element analysis (FEA) is done to find the force produced on the object for a particular current. The position of the object to be levitated is detected by implementing optical sensors. With the change in the position, the output of the sensor varies which in turn alters the current flow through the coil. Here a lab built electromagnet is used to suspend an iron ball. Generally used screw gauge system for modeling of actuator characteristics and to know the distance between the object and coil is replaced by travelling microscope to obtain more accurate results. Commonly used pair of sensors is replaced here by an array of receivers. The array gives wide control range. Also a small permanent magnet is attached to the suspended object to reduce the current magnitude through the coil required to suspend the ball. The sensor output with respect to position is obtained experimentally and plotted. A robust controller is also designed for the system. The simulation results are presented for the same.

Magnetic levitation Travelling microscope Array of sensors Robust controller