Abstract
In this study, we are trying to establish magnetic control system, hoping to modulate the direction and magnitude of the magnetic field. The size of most electromagnets is huge and they consume large electric current. We simulate the surface of the pure iron, and optimize the design to make sure the electric field is uniform. Because we use the square-circuit design, calculate the resistance of enamel insulated copper wire, allocate the wire to the proper place, we can create huge magnetic field and build an electromagnet that is suitable for our research; we also want to build an environment to control magnetic field with small electric current, so we use stepper motor to control the distance between two set of Neodymium magnet, and using other stepper motors to revolve the magnet. The magnet can revolve around the center and rotate by its own. With different direction and magnitude of the magnetic field, we can have lots of application, such as measure the Magnetoresistance.