Ray, B. (2016, June), An Inexpensive Control System Experiment: Modeling, Simulation, and Laboratory Implementation of a PID Controller-Based System  Paper presented at 2016 ASEE Annual Conference & Exposition, New Orleans, Louisiana. 10.18260/p.26212

\bibitem{asee_peer_26212}
  Ray, B. (2016, June), \emph{An Inexpensive Control System Experiment: Modeling, Simulation, and Laboratory Implementation of a PID Controller-Based System}
  Paper presented at 2016 ASEE Annual Conference \& Exposition, New Orleans, Louisiana.
  10.18260/p.26212

Biswajit Ray.  "An Inexpensive Control System Experiment: Modeling, Simulation, and Laboratory Implementation of a PID Controller-Based System".  2016 ASEE Annual Conference & Exposition, New Orleans, Louisiana, 2016, June.  ASEE Conferences, 2016.  https://peer.asee.org/26212 Internet.  26 Apr, 2024

\bibitem{asee_peer_26212}
  Biswajit Ray.
  "An Inexpensive Control System Experiment: Modeling, Simulation, and Laboratory Implementation of a PID Controller-Based System".
  \emph{2016 ASEE Annual Conference \& Exposition, New Orleans, Louisiana, 2016, June}.
  ASEE Conferences, 2016.
  https://peer.asee.org/26212 Internet.  26 Apr, 2024

@INPROCEEDINGS{asee_peer_26212
author = "Biswajit Ray"
title = "An Inexpensive Control System Experiment: Modeling, Simulation, and Laboratory Implementation of a PID Controller-Based System"
booktitle = "2016 ASEE Annual Conference \& Exposition"
year = "2016"
month = "June"
address = "New Orleans, Louisiana"
publisher = "ASEE Conferences"
note = {https://peer.asee.org/26212}
number = {10.18260/p.26212}
}

TY  - CPAPER
AB  - This paper will present a classroom-proven control system experiment that conveys the fundamental concepts of designing a closed-loop system, including the PID controller tuning.  The proposed experiment provides an opportunity for students to model, design, simulate, and implement a complete feedback control system in a very inexpensive way by using only a couple of quad op-amp ICs and a few discrete resistors and capacitors.

A mass-spring-damper mechanical system can be mathematically modeled as a position control system with object mass, viscous friction coefficient, and spring constant as parameters.  A transfer function of this second-order system can be developed with force as input and position as output to study open-loop response of the system.  Then a closed-loop position control system using a PID controller can be designed with reference position as input and actual position as output.  Students can simulate the complete system using Matlab/SIMULINK and develop a set of proportional (KP), integral (KI), and derivative (KD) coefficient values to meet the system’s step response specifications in terms of overshoot/undershoot, settling time, rise/fall time, system stability, and steady-state error.  Once the design is verified via simulation, the laboratory implementation of the system can start.  As shown in Figure 1, the second-order mechanical system can be modeled with three op-amps, and the error generation circuit and PID controller can be implemented with one and four op-amps, respectively.  This implementation approach lets students clearly see and manipulate each block of a typical feedback control system while still realizing a complete system with only two inexpensive quad op-amp ICs such as LM324A.  From a pedagogical standpoint, students are able to study the effects of KP, KI, and KD on system dynamics just by varying the three 100 k potentiometers, independently or any combination thereof.  This provides a simple and direct way to study the following commonly used PID controller configurations: P, I, PI, PD, and PID.  Figure 2 shows the system response for PI and PID controller configurations, illustrating the benefit of adding a derivative component to the controller in reducing overshoot and improving transient response and system stability.

The full paper will present details of modeling, Matlab/SIMULINK simulation, and laboratory implementation of the proposed control system with a focus on studying the effects of KP, KI, and KD on the system’s dynamic performance and stability as well as steady-state error.  A key goal of this paper is to present an inexpensive and easily implementable control system experiment via which students can investigate fundamental concepts relating system dynamics to controller configurations in a clear and concise manner.  A strong feature of the proposed experiment is that students have full access to the system, allowing them to investigate controller-plant interaction at a fundamental level.

 

Figure 1:  Implementation of a closed-loop feedback control system with PID tuning capability.

Figure 2:  System response with PI Controller (KP = 66, KI = 13) [left] and
PID Controller (KP =60, KI = 17, KD = 1.2) [right].





AU  - Biswajit Ray
CY  - New Orleans, Louisiana
DA  - 2016/06/26
PB  - ASEE Conferences
TI  - An Inexpensive Control System Experiment: Modeling, Simulation, and Laboratory Implementation of a PID Controller-Based System
UR  - https://peer.asee.org/26212
DO  - 10.18260/p.26212
ER  -