Modelling and control of a novel vibratory feeder

The system identification and real-time control of a vibratory feeder (VF) are discussed. The feeder simply uses a horizontally-vibrating flat bed to feed various parts. Only the 2D motions (translations in the x and y axes) are analyzed here. The system is nonlinear and highly uncertain, because the motion of the part depends on the Coulomb friction on the contacting surface. A modified pulse-width modulation (MPWM) signal is developed to control the vibration of the bed. A four-time-interval control algorithm is investigated so that both bed and part move in the desired manners. Both open- and closed-loop simulations of the VF system are implemented to verify the feasibility of the system model, the MPWM signal, and the control algorithms.