Feedback control for electromagnetic vibration feeder: (Applications of two-degrees-of-freedom proportional plus integral plus derivative controller with nonlinear element)

An electromagnetic-type vibratory feeder of is a typical transportation device used in automatic weighers. As existing feeders are driven by feedforward control, the so-called "firing angle control", the driver cannot negate sudden disturbances. In this study, we consider applying a feedback control for such a feeder system. First, we give the two details of modelings for the vibration part and for the electromagnetic force part. Next, a feedback control system is constructed for the electromagnetic vibration feeder for which we propose a two-degrees-of-freedom proportional plus integral plus derivative (PID) controller with nonlinear elements. Next, we apply the feedback control to the feeder with a standard trough. Finally, we consider a method compatible with many varieties of troughs by adjusting a nonlinear element. On the basis of the results of some experiments, we confirm that the two-degrees-of-freedom PID control is more effective than the conventional firing angle control.