Edge Position Controller is used for controlling the edge position of material in the process of Unwinding, Central Guiding, and Rewinding, the following Figure is the figure of assemble and installation of Edge Position Controller in the Unwinding system, it explains and shows that the edge position of material is detected by Photoelectric Sensor, generating a position-tolerance signal, and it is passed to Edge Position Controller for processing, after computing, Edge Position Controller sends a driving signal to a drive unit (this example is hydraulic cylinder), which moves the frame of feeding unit, then getting the purpose of Edge Position Control of material.