Session F1D INTEGRATING INSTRUCTIONAL TECHNOLOGY ...

Session F1D INTEGRATING INSTRUCTIONAL TECHNOLOGY METHODOLOGIES IN A STATE OF THE ART INDUSTRIAL CONTROL LABORATORY Wilfrido A. Moreno1 , James Leffew1 , Oscar Cárdenas2 , Niurka Ramos3 , Norali Pernalete1 , Franklyn Díaz1 , and Víctor Alvarado1 Abstract - Recent observations confirm the escalating concern of the general engineering educational community about enhancing the teaching of traditional Control Theory courses. The objective of this project is to improve the learning experience in a new Industrial Control Laboratory using the latest techniques in instructional technology by incorporating newly developed software tools in order to better deliver, not only the mathematical foundation, but also to enhance the important relationship of the interdisciplinary nature of a typical Introductory Control Course in Engineering. At the University of South Florida, Department of Electrical Engineering, an effort is under way to develop a set of Control Laboratory Experiments in a web-managed environment to introduce the students to techniques needed for the design and implementation of automatic industrial control systems. The Conclusions and Future Work estimate the impact of the innovations on the student, teacher and department. .

Introduction This paper summarizes the initial effort to introduce the WebCT tool into the Industrial Controls Laboratory, with the objective of enhancing the student’s learning process and preparation for the work force. It includes a complete explanation and description of the recent instructional technology methodologies in a state of the art Industrial Controls Laboratory On the one hand, there is clear evidence of the need to modify the current method of teaching Industrial Control Systems. The final report by the NSF/CSS Workshop on New Directions in Control Engineering Education expressed the necessity to include “...a set of diverse materials that integrate classical control methodology with crossdisciplinary examples, applications, software aids, and visual-interactive learning aids (based in WWW or CDROM access for maximum convenience) as an essential ingredient for preparing the student for a professional engineering career.” [1, p.55] On the other hand, modern computers, the World Wide Web (WWW) and software packages are excellent resources to improve the learning/teaching process. The introduction of technology into the educational process has been evolving

for many years. Recently, software has become available that is capable of managing a complete course, like WebCT. This package offers a wide variety of tools, which are capable of delivering distance learning to many students, wherever they are. Additionally, it has many quality features including visuals aids, interactive performance and cooperative work.

Antecedents Several universities are presently using Remote Laboratories to accommodate those students who cannot attend regular laboratory activities for a variety of reasons and to provide laboratory capabilities for campuses without on site equipment. For example, the University of Tennessee at Chattanooga (UTC) has developed an Internet Laboratory. Students have access to real data in real time and can perform experiments to control pressure, temperature, voltage, flow, position or speed without being tied to a fixed location. [2] Another example is the Virtual Control Laboratory of the University of Edinburgh. This laboratory consists entirely of virtual experiments. When used as a teaching aid before the physical lab experiments, student laboratory performance is greatly enhanced. [3] The article by Gadoura shows a broad revision of different multimedia applications in Control Engineering Education. The article presents some applications in Stanford University, the University of L’Aquila, Oregon State University and the University of Maine. It points to the importance of creating more real-world laboratory experiments with novel applications as a means to improve educator capabilities and overall education levels. Additionally, it expresses the need for continued update of the laboratory (computer visualization, interactive and virtual) environment as technology advances. [4] Another example is the Web-based Virtual Laboratory of the Department of Electrical Engineering of the National University of Singapore. This laboratory has been designed as a remote laboratory based on distance learning concepts. Its concept is a cluster of general-purpose and/or specialized instruments interfaced to a set of personal computer systems that are connected to the Internet. [5]

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University of South Florida (Electrical Engineering Department, Tampa FL, 33620) Universidad de Los Andes (Venezuela) 3 Universidad Simón Bolívar (Venezuela) 2

0-7803-6424-4/00/$10.00 © 2000 IEEE October 18 - 21, 2000 Kansas City, MO 30th ASEE/IEEE Frontiers in Education Conference F1D-8

Session F1D The last sample is the Control Engineering Laboratory of the Polytechnic University with virtual instruments used for real-time experimentation in a remote access environment. In this case, to minimize the lack of students’ real-time interaction with the experiment, the actual experimental setup is observed with a video camera. The video is sent to a Web page and the student’ remote computers receive the digitized compressed video feed. [6] All of these examples show the increasing interest and motivation for incorporation of computer-aided laboratory activities to promote distance learning.

Instructional Technology The Instructional Technology (IT) is a source of information, tools, knowledge and delivery of services to support the learning/teaching process. Fardanesh states that IT “…presents solutions, strategies, procedures and models for execution of instruction for different learners and in a variety of conditions.” [7, p.3] The instructional technology methods are not only just innovative tools for research; in teaching they should and will become instruments for deliberate use to improve learning. In this case, specific and significant effort will be expended to incorporate the WebCT environment in order to promote better access to different and multiple sources of information on the WWW. These sources will include content, references and companies interested in study areas associated with the Laboratory. A web-based implementation will offer many additional features not available in a classic laboratory environment, which will be describe in the next section. This prototype described here in was designed based on an operational and functional approach. The first stage was to assemble the instructional design. The final user would be supported through the system to pursue the Laboratory objectives from low-level to high-level skills, including critical thinking concepts. However, the instructional design framework based on only Web-based environments may not be a complete solution by itself. Furthermore, when this learning process is instituted with a total absence of assistance and supervis ion to orient it, loss of reliability of the educational technology resources ensues. As an alternate experience, in this project basic concepts of instructional design were applied to overcome these drawbacks in teaching and learning methods. The next phase was the design of virtual and real experiments that were organized to accord the instructional sequence. Finally, all content was adapted to WebCT where in each page the student receives clear instructions to continue.

skills through mediated information and instruction, encompassing all technologies and other forms of learning at a distance”. [8] Some research studies have been quite consistent in finding that distance learning classrooms report similar effectiveness results as reported under traditional instruction methods. In addition, research studies often point out that student attitudes about and satisfaction with distance learning are characterized as generally positive. [9] Some of the features of distance learning are: Instruction monitoring, performance standards, timely feedback, cooperative learning, active learning, time on task, search on the web and diversity. One can find two categories of distance education delivery systems: Synchronous and Asynchronous. • Asynchronous: Asynchronous instruction does not require the simultaneous participation of all students and instructors. Rather, students may choose their own instructional time frame and gather learning materials such as E-mail, CD-ROMs, audiocassette courses, videotaped courses, correspondence courses, WWW-based courses, etc. according to their schedules. The advantage of asynchronous delivery is that it provides the student with flexibility of location and time. • Synchronous: Synchronous instruction requires the simultaneous participation of all students and instructors. Included are the Web-managed courses, interactive TV, audio graphics, computer conferencing, video conferencing and others. The advantage of a synchronous instruction delivery is that it offers “real time” interaction. [10]. Both concepts can be integrated in the Laboratory concept with virtual and/or real experiments, see Figure 1.

Figure 1. Distance Learning and Remote Laboratories.

When designing web-based courses, one must be aware of different levels of involvement: § Web-enhanced: Course meets on a regular basis and Distance Learning some materials are on the web. § Web-delivered: All materials are on the web and no scheduled class. The United States Distance Learning Association defines § Web-managed: Closed environment, password distance learning “…as the acquisition of knowledge and protected, student, site tracking and interactivity. 0-7803-6424-4/00/$10.00 © 2000 IEEE October 18 - 21, 2000 Kansas City, MO 30th ASEE/IEEE Frontiers in Education Conference F1D-9

Session F1D [11]There are several Web-Managed Software packages available: Cyber Ed, TopClass, Web Course in a Box, CourseInfo and WebCT. The University of South Florida is licensed to use the last two software packages. The team, who developed this project, decided to use the WebCT format for an Industrial Controls Laboratory.

WebCT Introduction WebCT is a software package that facilitates the creation of a Web-managed educational environment. It is used to create entire courses or enhance an existing course. Different tools are available to users such as content pages, file uploading, bulletin boards, chat and electronic mail, student selfevaluation and grading capabilities, on-line exams and references, search and others features. Some advantages are: v Versatile: Includes different resources on the web. v Adaptable: Can be adapted for subject area. v Communication: E-mail and personal interaction. v Anytime: Open 24 hours, 7 days a week. v Dynamic: Modifiable anytime. v Anyplace: Can be accessed wherever you want. The most important features of the WebCT format are the capability to provide password protected access, grading and online testing, private e-mail and chat rooms. A WebCT course is like a virtual classroom. The student has direct access to his/her teacher and classmates, either in asynchronous or synchronous mode. The WebCT course is a private place where teachers and students share the same goal.

Overall Laboratory Concept The goal of this laboratory is to introduce students to the most recent, state of the art, software and hardware technologies for the design and implementation of automatic control systems. The student is first introduced to the basic components of an automatic control system and the available hardware/software tools in the laboratory. Then, a more detail approach to Programmable Logic Controllers (PLC’s) and Data Acquisition Systems (DAQ) is given throughout the semester. Finally, the concepts of system modeling, tuning control and primary and final control elements are given at the end of the course so students can evaluate if their design satisfies desired specifications or characteristics. A final project is performed at the end of the course in which students apply all the concepts learned with the specific tools provided. [12] At the University of South Florida’s Department of Electrical Engineering, this laboratory concept has been implemented using a WebCT format so that students have all the experiments available via the WWW. The WebCT format provides students with the ability to access the experiments, their grades, the theoretical background for

each experiment and real time simulations as pre-laboratory activities as well as to consult related material on the Internet. Instructors, on the other hand, are provided with better control of the student’s activities and a more detailed organization of the information related to the course. These factors provide for a higher quality of interaction between students and the instructor. The first step taken at the University of South Florida was to build an experiment for a remote industrial control laboratory via the Internet. This experiment consisted of the speed control of a DC motor over the Internet. [13,14] The software tools used to implement this experiment were derived from software packages provided by National Instruments Inc. LabVIEW and the Internet Developer’s Toolkit were the two main software tools used in the developmental stage of this experiment. A set of appropriate user interfaces, Web pages and LabVIEW Virtual Instruments (VI’s) were integrated to structure a remote control via the Internet. [15] The design concept was based on Control and Data Acquisition Systems techniques. It consists of the following elements: computer technology, Programmable Logic Controllers (PLC), Data Acquisition Systems (DAQ), and software programming tools. A design framework was implemented which included real-time database and display editors (i.e., historical data, alarms, sequence of events, and automatic generation control) all of which were supported by up-to-date hardware/software tools. Students have the option to choose to control the speed of the DC motor using the controller programmed in LabVIEW or the one loaded into the PLC using RsLogix 500. A Pentium PC, equipped with the latest software and hardware technology, was connected to the Internet and functioned as the Internet Server by executing the program entitled “Windows HTTP Server” as shown in Figure 2. The server periodically “pools” information through the Ethernet card. The site information includes an updated system status, images and system parameters. These signals, such as voltage level, set point operation and some other features are collected onto the hard disk of the server. This system is password protected. The user interface provides easy remote access to the different control units by using a discrete snap shot image of the control panel system. It offers extensive capabilities for teleoperation, access control, unlimited monitoring, and other multimedia services. In addition, remote control, network reliability, and safety features are integrated into the design tools (Matlab, Simulink, LabVIEW, Rslinx, Rslogix 500, PLCs, DAQ Board, etc.). Each of these communicates with the server, the system, and the user interface via a computer network.


Session F1D his/her learning. All of the tools are organized with different icons that afford ease of movement into the virtual classroom.

User or client

User or client

Remote and Local User Interface Control

Server

Station

PLC DAQ

Local System

Process 2 Process 1

Processes

Figure 3. Experiment Page in WebCT format. Figure 2. Overall System Diagram. At the moment, this is one of several experiments available through the WebCT Controls Laboratory site. This Controls Laboratory allows students to demonstrate and validate the study of the analytical concepts taught in the first feedback control system course. Students are introduced to the real-world control and modeling issues with the most recent, state of the art, technologies. In addition, they are exposed to writing and maintenance of engineering reports, a very common practice in the professional field of engineering. In the future, the plan is to implement a shared laboratory concept in which two or more departments will be involved in sharing equipment and in coordinating the experiments. Students will then be exposed to the multidisciplinary nature of Control Systems and to the faculty and students from different disciplines. Furthermore, the concept of shared laboratories could be extended to different Universities or campuses.

WebCT Course: Industrial Control Laboratory The student enters the WebCT environment by passing through the Welcome Page, The Home Page and finally he/she arrives at the Experiment Page. (Fig 3) In this page, the student selects the current experiment. Each experiment follows the same sequence. It includes Objective, Theoretical Framework, Pre-laboratory Activities, Activities (virtual experiment or real experiment) and Postlaboratory Activities. In this WebCT course the student has many sources of information for help in order to optimize

An example of a real experiment using WebCT via the Internet is, the DC motor speed control system. It consists of a web interface that controls an existing application such as the DC Motor Speed Control (Virtual Instrument) VI. The application DC Motor Speed Control VI was created to make it accessible from a web site. The example uses HTML pictures. The left frame displays the DC Motor Speed Control VI process panel image and the right frame is used for controlling the DC Motor Speed Control VI. All control is done through calls to the victrl.vi CGI VI. The victrl.vi CGI is used to set Boolean, numeric and string control values of any running VI. It is also used to open and close panels of other VIs and to set VIs running. More information about the source code of victrl.vi is described in [16]. When the process is running, it generates a dynamic image of the control panel of the system and refreshes it every second. Then, if a click on the control panel of the system on the user side is made, a dynamic image is reloaded with the new action, and the server starts refreshing to keep the server updated for real-time monitoring and control. At the same time a real-time video image and audio of the system is received, so the student can see the results with the HTML page and the real-time video. Actually the video is not embedded in the HTML of the system. Tests are shown in Figure 4. The HTML pages of the process are composed of two pages: one contains the HTML code that acquires the image, and the other contains an updating picture of the control panel of the DC Motor Speed Control VI. The code is presented in more detail in [16]. This code is provided with the CGI Write Reply VI to update the screen of the user with an embedded image of a server-push animation of the front panel of the DC Motor Speed Control VI. The image updates


Session F1D approximately once a second for a duration of 600 seconds. The animation works only with browsers that support serverpush animation. Other browsers simply receive a static image.

Figure 4. DC Motor Speed Control Web Page. Consider figure 4, the process is started under given conditions of PID gain, no load applied, and a set point of 900 rpm. It shows the process’s response; the PID output voltage, the generator’s state, and the load switches. Other tests over the Internet were performed such as a change in the set point during continuous operation of the system and switching the generator and the load on/off.

Conclusions In this paper a prototype of a Web-managed Laboratory Course based on the use of the WebCT format has been presented. This developed design has many advantages capable of serving a great variety of people at anytime, anywhere, in interactive mode. The reason to pursue this instructional methodology is the importance of communication and monitoring in the learning process. With this method the professor has the ability to have ongoing interactive contact with the students. Each experiment establishes for the students: a guide for searching the WWW, simulations in real time, a cooperative environment between students and teachers, quick access to the grade record and the opportunity to do remedial activity if required by the teacher; for the teacher: a permanent information update, a confidential communication with the students, increased student motivation and permanent control of the students activities; for the department: a maximization of the use of expensive laboratory equipment,

optimization of the use of the human resources (hour/professor) and a better use of existing facilities. With the use of Instructional Technology the following goals can be reached: • Increase motivation • Develop a graphical approach to improve concept visualization • Activate learning • Promote cooperation and interaction among students • Introduce students to the world of virtual instruments • Facilitate access for students to relevant Instrumentation and Control sites in the WWW The set of ideas and experiments developed during this project, as well as the evaluation procedures are directly applicable to the development of an enhanced Instrumentation Laboratory and related engineering laboratories. Additionally, other, non-engineering, multiuser laboratories can benefit directly from this endeavor. The outcome of this work is the result of a team effort where expertise from engineering educators and instructional designers was focused on a common goal and the use of the latest software/hardware tools in conjunction with existing instructional methodologies were employed in the development of a Web-managed laboratory concept.

Future work It is within the College of Engineering goals to support cooperative interaction within departments in order to create interdisciplinary experiences for the students. The Electrical Engineering Department is working closely with the Chemical Engineering department in the design of a common Controls Laboratory, which will be developed using the new Industrial Controls Laboratory format. Additionally, in order to evaluate the performance of the Industrial Controls Laboratory under WebCt a set of activities have been programmed to be performed concurrent with the first Laboratory session offered. These assessment procedures are being designed to evaluate the software tools, the interaction between the different employed technologies, and the instructional design.

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Antsaklis, P. & Associates, “Report on the NSF/CSS Workshop on New Directions in Control Engineering Education” Control System IEEE, October 1999, V.19, No. 5. pp. 53-58. Zurawski, L. “ Internet Laboratory Tests Control Systems Parameters”. Control Engineering. Online. August 1999. http://www.manufacturing.net/magazine.archives/1999/ct10801.99/ 9908cy.htm The ECOSSE Control Hyper Course. University of Edinburgh. 1998 http://www.chemeng.ed.ac.uk/ecosse/control/course/map/intro.html Gadoura, I. “Multimedia Applications in Control Engineering Education” Helsinki University of Technology, 1997.


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http://saato014.hut.fi/Hyotyniemi/publications/97_report106/GAD OURA/GADOURA.html Chen, S. “Web-Base Virtual Laboratory” National University of Singapore, 1999. http://vlab.ee.nus.edu.sg/vlab/ Overstreet, J. and Tzes, A, “An Internet -Based Real-Time Control Engineering Laboratory” Control System IEEE, October 1999, V.19, No. 5. pp. 53-58. Fardanesh, H. “Instructional Technology at its Exigency”, Journal of Instructional Science and Technology, V. 3, No 3, March 2000. http://www.usq.edu.au/electpuble/e-jist/Vol3No3/index.htm United States Distance Learning Asso ciation, 1999: http://www.usdla.org/02_definition.htm The Institute for Higher Education Policy. “What’s the Difference?” A Review of Contemporary Research on the Effectiveness of Distance Learning In Higher Education, April 1999 WestEd Agency, San Francisco, 1995 http://www.wested.org/tie/dlrn/distance.html University of South Florida. “Improving Teaching and Learning trough Web-Enhanced or Web-Delivered Courses” An Intensive Workshop on WebCT, Tampa. FL., January 26-February 23, 2000. Industrial Controls Laboratory. Reference Manual. University of South Florida, 1999 Cardenas R. Moreno, W. Pernalete N. and Diaz, F., “Prototype of a Remote Industrial Controls Laboratory via the Internet. IASTED International Conference, Santa Barbara, CA, October 28-30, 1999. R.A. Cardenas, W.A. Moreno, N. Pernalete, F. and Diaz, F., "Development of an Industrial Remote Controls Laboratory Via Internet: A "Real" Industrial Application" IV Congreso Interamericano de Computación Aplicada a la Industria de Procesos, San José, Costa Rica, 2 al 5 de Noviembre de 1999. National Instruments Inc. LabVIEW Reference Manual. 1998. Cardenas, R. A. “Remote Supervisory control via the Internet” Master’s Thesis. University of South Florida. 1999.
