Design and digital implementation of a pid controller for a simulated rotary knife cutter /

Abstract

This investigation deals extensively with control system engineering in both theoretical design as well as direct implementation in both analog and digital terms. A rotary knife cutter, which is a commonly used piece of manufacturing equipment, is simulated in a laboratory environment using two independent servo-mechanisms placed side-by-side. The fIrst servo simulates the infeed roll, while the other simulates the knife cutter. The object of this study is to use classical Pill control, designed via Matlab and Simulink, to manipulate the overall system performance. Digital implementation is achieved using control codes programmed in MS-Quick C, interfaced through a PC and a digital-to-analog and analog-to-digital converter. The physical system and its simulation, the mathematical modeling of the servo-systems, and the design and implementation of the controller are all presented within the context of this study. Final implementation shows that direct digital implementation of the PID controller is adequate for the rotary knife cutter. However, there are several problems with the controller when switching from speed control to position control due to the controller design as well as the presence of noise in the system.