Computer algebra system applications in process control

This paper discusses the use of the computer algebra system Maple for demonstrating and applying process control principles. Control engineers and technicians must be familiar with the simple proportional-integral-derivative (PID) controller for single loop control, and with Bode plot analysis for selecting tuning constants and stability range for the controller. Two Maple procedures are discussed: PID() and Bode(). Procedure PID() provides the open loop plant response and the closed loop response to set point changes for a single loop with a PID controller in continuous or sampled environments. Bode() provides amplitude ratio (AR) and phase plots with appropriate scales and grid lines. These procedures demonstrate how the symbolic as well as numerical and graphical capabilities of Maple can be incorporated in procedures that can facilitate the analysis and design of control systems.