Experimental and Virtual Laboratories in Distance Learning - CiteSeerX

Experimental and Virtual Laboratories in Distance Learning RADIM FARANA, LUBOMÍR SMUTNÝ, MAREK BABIUCH Department of Control Systems and Instrumentation VSB – Technical University of Ostrava 17. listopadu 15, Ostrava-Poruba, ZIP: 708 33 CZECH REPUBLIC

Abstract: - This paper is focused to the use of experimental and virtual laboratories in the teaching of information systems, closely connected to control systems. The Paper presents experience with developing real laboratory tasks in wireless communication systems, using GSM controller and other specialised equipment. Students have developed these laboratory tasks and web connection to these tasks during their semester project in the subject „Database systems“. The projects integrate data measurement, control systems, database systems and other parts and make demands on students to solve these problems together as a whole. This has proved a useful way to grasp the complexity of separately taught subjects. Key-Words: - experiment, virtual laboratory, distance learning, information system, database

1 Introduction Four years ago the Faculty of Mechanical Engineering changed all study programmes to the serial study system, according to the Bologna Declaration. The accreditation process motivated us to change the study plans completely. Now the students are in the third year of a three-year Bachelor programme and have started study specialisation. The study branch subject starts in the fourth semester of the Bachelor studies; the Master study has only a few connected subjects. This is a huge change in study plans. Previously the study system had been parallel and only a small number of bachelor students continued to the master study through a special year of study, including background subjects like Mathematics, Physics, and Mechanics, etc. Now there is more space for the study branch subjects than before, but we have to differ the subjects for bachelor and master study. Previously the subject contents had been similar from 20% to 50%. The second problem is to fill in the study branch subjects. It is now much more time for specialisation. Three specialisations have been made in our study branch “Engineering Computer Science and Control” in the bachelor programme. They are: • Control Systems – focused on basic knowledge of control systems, instrumentation, sensors etc. • Application of Computer Science – focused to computer hardware and software, database systems etc. • Technical Management – information systems, engineering management etc. Thanks to the changes in the studies, we have obtained the possibility to completely change the subject content. At first, we changed the content of subject “Databases and Internet”, which is the fundamental subject in the specialisation Application of Computer

Science. The previous subject content was oriented on database system development only and laboratory tasks were focused on database system problems, Internet connectivity etc. It is clear that we could not change the complete subject content, the main database problems have to be included in the lectures. The principles of exercises taught to show how databases and information systems are connected to other control systems parts were changed. There are many different problems and systems using databases or other ways to store data for their processing, like visualisation and supervisory systems [4, 6, 7], measurement systems [2, 8], instrumentation systems [5] etc. As a first step to connect database problems with other parts of the studies, we found some problems taught in other subjects and included them in the exercises: • Measured data storing and processing (Instrumentation, Sensor Systems). • Control system analysis and further data processing (Control System Theory). • Technological process data storing and analysis (Process Visualisation). • Production data analysis (Management systems). This strategy helped students develop their semester work, bachelor and diploma thesis from these fields of interest. Unfortunately, it was complicated to take data and databases from so many different fields of interest, because the problems had been solved in different laboratories with different equipment. This way is also good for completing a bachelor or diploma thesis, but very complicated for standardised teaching. Realising this, we started to build a special database and information system laboratory, including hardware and software equipment:

• • • • • •

Database server (Microsoft SQL 2000 Server). Application server (web server with ASP technology support). Client program developing systems (PowerBuilder, Microsoft Access database). Data acquisition systems, measurement systems. Supervisory control systems, remote control systems. Control system developing software.

Web server

Network

Specialised laboratory

SQL server

Laboratory tasks

Fig. 1 – Information Systems Laboratory

2 Information Systems Laboratory Figure 1 shows the basic structure of a built laboratory. The main part is a server farm located in a special computer room together with network hardware. All servers are remotely operated using the network. The computer laboratory has been equipped with software for client tools development. Most important is a specialised laboratory, which is built now. The equipment installed in this laboratory is: • Bar code readers – for the development of typical warehouse and sales information systems with online data input, • Simple input carts – for the development of data measurement and data processing systems, connected to existing laboratory tasks used in other subjects from the area of control systems and instrumentation, • Special GSM controller – for the development of simple measurement, data storing and remote control systems with the use of knowledge acquired in subjects from the area of control systems theory, sensor systems and data processing systems, • SCADA/HMI software connected to the laboratory tasks for system visualization and control. Laboratory tasks are used during the exercises for example for data source connection, data storing and online data processing. Some of them need knowledge from special subjects like real-time system programming [1], non-linear control theory [9, 10] or special data processing methods [8]. An important use of this equipment is also in completing semester work, which is an integral part of completing a subject. Figure 2 shows a typical laboratory task developed using GSM controller for data collection and data processing. Web connection has been also developed to present collected data as a part of laboratory task solution. This way forces the student to use knowledge from different study courses.

Client software

Computer laboratory

Data transfer

ª

Data processing

SMS GSM net

Central database I/O

RS 232 GSM controller

Laptop computer

Local database

Dallas Sensor

iButton input

Fig. 2 – Typical laboratory task with use of GSM controller

3 Virtual Laboratory Connection The next logical step was to change the focus to remote laboratory tasks connections. We have good experience with SCADA systems InTouch and Control Web 2000 [4, 6, 7]. These give us the possibility for creating client applications connected to real laboratory tasks by Internet, and also including standard programming interfaces like ODBC, which can be used for developing a data source component. Thanks to this standard interface we can use the SCADA client program as a data source and store the acquired data in the database for developing database client systems. Students appreciate the real system behaviour, which they have analyzed during studying previous courses from the area of control systems theory, identification and modelling. The students cooperate on the production of software support, especially web support for their diploma thesis, mainly in applications utilising subjects such as Automation or Measurement and Sensors Engineering. These diploma projects are plugged into the education process upon completion. The advantage is a presentation of the subjects as well as the Department of Control Systems & Instrumentation. These applications are also used to a large extent in the tutorials of the subjects mentioned above. However, the decisive advantage for the diploma students is also the interconnection between the area of Automation Engineering and Applied Informatics.

Fig. 3 – Presentation of Sensor and Measurement Laboratory

4 Web Support of the Sensors and Measurement Laboratory In the Sensors and Measurement Laboratory the teaching of several subjects of corresponding area takes place. The support of this teaching was developed at the CSI Department using practical applications. This application

module contains a description of all working places, completed by an instruction and a code for practical work and the order plan of the measurement.

Fig. 4 – Web education pages for support of the Sensors and Measurement Laboratory In a Figure 4 can be seen the main window of the application web module. There is a full view of the Sensors and Measurement Laboratory. ‘Clicking’ on a particular working place the associated with place is shown. After the selection of an actual task, we can see the introductory manual for the laboratory exercise. The introductory manual includes the progress of measurement, a description for using devices and the diagram. Also available are the theoretical analysis, mathematical equation and the preparation template of the table for measured values. This application module solves the problems with the distribution of introductory manuals to students, material supply and time demand. The mentioned application is, of course, dynamic and it is possible to gradually complete it and upgrade it. Another application was created in PHP scripted language with SQL server support. This application, which supports the education at the Laboratory of Sensors and Measurement, is an application program module for student attendance and evaluation. This application module removes the use of a paper attendance list and makes it easy for the tutor to have a checking system for attendance and giving credits. This application also enables assessing students’ work during the semester. A student is assessed by the records from the exercise – a particular measurement task and a credited project. This assessment is possible to complete within a web application. The administrators of this application are the tutors, who give lessons at these laboratories. The tutor must complete an appropriate web form for creating an attendance list at the beginning of a term. This

application is user-friendly and has intuitive commands. There is an updated timetable for the tutor after the generation of attendance list (see Figure 5).

Fig. 5 – The web timetable and a list for evaluation and checking attendance The attendance list of a study group is shown after ‘clicking’ on particular subject. The tutor of the practical exercise completes the names of students. The fourteen attendance boxes (number of weeks of the term) are prepared; the other boxes are available for evaluation throughout the term. Students’ acquired points are automatically adding up, so the actual state of point evaluation can be seen. Of course, the students may look at these pages for their results.

5 Conclusion We have now the first experience with solving these problems in the teaching process, and they have showed us that it is complicated to prepare suitable laboratory tasks. However, students are achieving good results and these problems are popular, especially among good students, because they can synthetize their knowledge from different courses.

Acknowledgements: The presented results have been obtained with the support of the Czech Ministry of Education, Youth and Sports, during completing of research project MSM 272300012. References: [1] FOJTÍK, D. Návrh a realizace úprav zvyšující determinovatelnost zpracování zvoleného požadavku IRQ v MS Windows NT/2000/XP využívající obvody PIC-8259A. In Proceedings of XXVIII Seminary ASR 2003 „Instruments and Control“. Ostrava : VŠB-TU Ostrava, 2003, pp. 69-81. ISBN 80-248-0326-7. [2] KOČÍ, P. Assessment of machine Tool Dynamic Properties. Acta Montanistica Slovaca, Vol. 8, 4/2003, pp. 179-181. ISSN 1335-1788. [3] KULHÁNEK, J. Distributed Simulation with Variable Parameters. In Proceedings of XXVIII Seminary ASR 2003 „Instruments and Control“. Ostrava : VŠB-TU Ostrava, 2003, pp. 178-180. ISBN 80-248-0326-7. [4] LANDRYOVÁ, L. Monitoring Technological Processes in SCADA/HMI System with the Support of Decision Making. In Proceedings of International Carpathian Control Conference 2003. High Tatras : TU Košice, 2003, pp. 143-146. ISBN 80-7099-509-2. [5] SMUTNÝ, L. Smart Instruments in Wireless LAN, In Proceedings of International Workshop on Intelligent Mining Systems. Fukuoka (Japan) : KYUSHU University Fukuoka, 2002, pp. 85-90, ISBN 80-86111-90-3. [6] ŠKUTA, J. Control and monitoring of technological processes with LAN and ILAN support. Ph.D. Thesis. Ostrava : VŠB-Technical University of Ostrava, 2003, 199 pp. (in Czech) [7] ŠKUTA, J. & BABIUCH, M. Vzdálené ovládání PC ze systému Control Web 2000 v síti LAN. In Proceedings of XXVIII Seminary ASR 2003 „Instruments and Control“. Ostrava : VŠB-TU Ostrava, 2003, pp. 339-341. ISBN 80-248-0326-7. [8] TŮMA, J. Signal Analyse, the software support for education of signal processing. Acta Montanistica Slovaca, Vol. 8, 4/2003, pp. 159-161. ISSN 13351788. [9] VÍTEČKOVÁ, M. & VÍTEČEK, A. Modulus Optimum for Digital Controllers. Acta Montanistica Slovaca, Vol. 8, 4/2003, pp. 214-216. ISSN 13351788. [10] WAGNEROVÁ, R. Nonlinear Control Systems Synthesis. In Proceedings of 3rd International Carpathian Control Conference. Ostrava : VŠB-TU Ostrava, 2002, pp. 751-756. ISBN 80-248-0089-6.