Hypermedia Teaching of Mechanics- MechANha Thorsten
Hampel
Reinhard
Heinz-Nixdorf lnstitut Universitat-GH Paderborn 33102 Paderborn +49 5251 60 6551
hampel@ uni-paderborn.de Ferdinand
rks@ uni-paderborn.de
Ferber
Wolfgang
Laboratorium fur Technische Mechanik Universitat-GH Paderborn 33100 Paderborn +49 5251 60 2282
H. Mijller
Department of Mechanical and Chemical Engineering Heriot-Watt University Edinburgh EH14 4AS +44 131 451 3689
jferbl @Itm.uni-paderborn.de
[email protected] integration in our didactic concepts: All of our animation systemsvisualise effects and parameterswhich are covered in our lectures and tutorials. Hence, by modifying these parametersin animation systems,studentsget a much better idea of the underlying physical and mathematical aspects. Modern electronic learning environments offer possibilities to focus on a student-centred approach for learning. Therefore the mechANZma knowledge-baseand information system develops new forms of teaching and learning methods. The problem of conventional learning, for example with the help of blackboards, flip charts and overhead slides, makes non-integrateduse of thesemedia. A student who attendsa lecture with many other students,e.g., twice a week, is not able to transfer the presentedmaterials to tutorials, or even to access literature referenced in the courses at home. Hence no continuous access to the essential educational material is guaranteed. However, a student should have accessto the same material regardless of the place where me learning takesplace. Especially, materials worked on in group meetingsor presentedin a lecture should be available whenever needed. The sameholds, of course, for the own homework of the students which might be presented in a tutorial. A student who does his /her homework must get me samematerials as in group working at the university or during the lectures. In the classic form of learning, this continuity was realised in a primitive form by means of pen and paper. Students prepare lessonsby reading and by browsing through books and papers, and they annotate their copies or their own summaries. In tutorials and lectures they have to write down what is written on the blackboard and compare their notes with referencedbooks and papers. In the context of collaborative learning it becomes more and more difficult for the students to lively participate in the ongoing
1. ABSTRACT In this paper we describe the mechANZma project, a joint venture between the department of computer science and the laboratory for mechanics at the University of Paderborn, Germany. 1.l Keywords Hypermedia learning, co-operative learning, studentcentred learning, multimedia, animations, visualisations
2. INTRODUCTION The term rnechANIma tries to establish a connection between “mechanics” and “animation.” The mechANZma project is not simply a computer program or a collection of materials for a mechanicscourse, but rather it stands for a philosophy of new methods for the teaching and a better understanding of mechanics. We try to develop new methods and didactic concepts of teaching mechanics in many different courses taught at the University of Paderborn. The evaluation of new teaching environments and didactic arrangementsfor me daily use of new media in lectures, tutorials and student assignmentsis a particularly important part of our research. Animation systems developed by ourselves offer many advantages for the Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, to republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. ITiCSE ‘98 Dublin, Ireland 0 1998 ACM l-58113~OOO-7/98/0008...
Keil-Slawik
Heinz-Nixdorf lnstitut Universitat-GH Paderborn 33102 Paderborn +495251606411
$5.00
112
discussion and at the sametime, take notes which they will used later when they prepare for their exams. Additional successful and effective forms of learning need studentcentred structures of teaching. Student-centred forms of learning are defined as presenting different views on the subject to allow students to develop a personal and individual understanding. This may be achieved by the use of electronic media called multimedia and hypermedia with the help of new educational didactic concepts and appropriateinfrastructure. Modern electronic learning environments offer possibilities to enhance a student-centred approach for learning by providing course materials just in time and with new ways of representation. To achieve better success in the understanding of the presentedmaterial and in order to let students develop their own insights in the topics, it is necessaryto offer a wide range of high quality information. The student has to extract the core information from a multitude of imported facts. In conventional forms of learning the students get the information step by step (portions of the presentedsubjects)and they are required to take an examination later. The students do not feel responsible for the selection of the information. Modern forms of learning require the willingness to accept responsibility for the selection and for the filtering of fundamental knowledge. The processof extracting the real essencemay be defined as the real achievementof learning. The social embedding of an individual learning process is mandatory in this form of teaching in order to create a motivating and stimulating atmosphere which helps the individual student to cope with the complexity of the materials, and which may prevent him for getting lost in hyper(media) space. In addition, the systematicexploration of the diversity and variety of concepts is emphasised through presentationof “one-best-way solutions”. The goal of the mechANZma project is to reduce the break-down in the use of electronic media and to create an interactive learning environment that can be actively worked upon by the students. Such an integrated approach cannot be accomplished by a single research group that createsa high tech island within the department of the university. The term “Alltagspraxis” (every-day-life practice) [2],[3],[41 has been used to indicate the goal of setting up a learning suggestive infrastructure that can be used under the typical constraints of the day-to-day teaching constraints imposed at a university. 3. COMPUTER SUPPORTED COOPERATIVE LEARNING One goal of the mechANZmaationproject is to achieve of a continuous flow of information between the students and the lectures. Electronic mail and the concept of Workgroup computing are widely spread in of our modern society.
113
Large companies use intranet solutions and groupware products to achieve a faster and less complicating flow of information. At non-computer science institutions of our university the concepts are not always consistently implemented. Therefore we try to establish a new “communication layer” and structure on top of our traditional organisations and forms of communication with our students. Studentscan communicateby electronic mail among each other and, of course, send emails to the staff. A few years ago we developed the idea of a direct access for students to all teaching material available at our institute, the Laboratory for Technical Mechanics (LTM). As a consequence,we have established a special Webserver called Hyperg [l] now Hyperwave. Hyperwave allows a more structured design of web publishing and active working with the materials than conventional web publishing systems. Hyperwave developed from a specialist’s system to a widely used modern Web information server, which may be accessedby common internet WWW clients, such as the Microsoft Internet Explorer, Netscape etc. Hyperwave implements a fully object oriented hypermedia database which allows to integrate all digital media such ashypertext, movies, sounds and animation. Especially the Hyperwave feature for the protection of documents with special accessrights, Unixlike group and user structures are necessarypre conditions to organise a course based on electronic media. Limited accessto documentsis particularly necessaryfor documents which underlie copyright constraints and may only be read by the registered participants of the course. Consequently, access rights and a user /group structure are absolutely essential for the use of Web-basedteaching environments. Hyperwave offers an easy way to use user interfaces including a set of special tools which allow in a very simple interactive way to insert hypertexts and all forms of hypermedia documents onto the server. On Microsoft Windows PC platforms it is even possible to down- and upload documents into the databaseby simply drag and drop documentsand icons into the server structure mirrored into the Microsoft Explorer. Additionally the Hyperwave information server offers special forms of structuring the material with the help of “collections” and “clusters,” a concept equivalent to traditional file systems. Besides the featuresmentioned above, Hyperwave allows for a full text search over the whole database which involves rather complex search terms, e.g., regular expressions, which makes it possible to work with a large number of hypermediadocuments. As a webserver Hyperwave guaranteesthat students have continuous access to the latest release of electronic documents. Mistakes which are found in lectures or tutorials can easily be corrected and published on the information server. Printed versions require much longer turn-around times. It is even possible for students to put
programming environments in order to find an alternative for the Visual Basic language which can only be used on PC platforms. The screenshot below (Figure 2) shows first results. Our experiences indicate that especially visual programming environments such the IBM Visual Age Environment offer a modern object oriented environment for application design. One important aspect for the selection of Visual Age are the mechanism provided to easily design user interfaces. The rather complex interface design of conventional programming environments can be realised in a highly interactive way. One of our students developed a system for the course on statics (Figure 2). With the help of that visual programming environment the programming effort could be realised within two months.
their homework on the server and discuss it in tutorials. This concept called “learning-supporting infrastructure” was introduced by [:!I for collaborative learning with the help of integrated teaching and learning environment and satisfies many requirements to achieve more flexible forms of combining individual and social learning processes.
Figure 1: One part of the mechAMma system developed by our students
Figure 2: Prototype of a visualisation system as a JAVA applet
Animation systems developed by ourselves offer a number of important advantages for the integration in our didactic concepts. The most important aspect is that all our animation systems visualise exactly the effects and parameters addressed in the lectures and tutorials. Hence, by modifying these parameters in animation systems, students get a much better idea of the underlying physical and mathematical effects. The next step for us will be the construction of a JAVA bean set for the fast and easy creation of additional visualisations an animations. With the help of such beans as mechanics elements it will be much simpler to create an animation with an visual JAVA development environment. The programmer simply has to compose and combine beans out of an set of visual components and arrange them with a low amount of time. An additional advantage for the use of JAVA will be to make use of the various modern class libraries presently developed by SUN or other JAVA developing groups. Currently SUN is developing a special 3D API for the construction of highly interactive 3D applications and visualisations. First tests for the animation of our optical experiments show good results. The visualisation of a “compressive edge load on a half plane” which is shown in Figure 3, allows to manipulate all necessary mathematical and optical parameters in a very
4. VISUALIZATIONS AND ANIMATIONS The requirement to tisualise complex mechanical effects was the initial spark for the mechAhVma project. A few years before the term “multimedia” was created we had tried to develop small simulation programs, e.g., to visualise caustic ([!i],[6],[9],[10]) effects, which are difficult to present in real experiments. One important aspect of our concept of mechANIma is to use popular programming environments such as Microsoft “Visual Basic” or Borland “Delphi” which can be handled by students without special knowledge in computer science. Consequently, we are still testing a great range of visual development environments and computer languages. However, so far the best results were achieved by using the Visual Basic development kits. Our experiences show, that students of mechanics only need 4-5 weeks to adjust and to produce results with a appropriate cost-to-effort ratio. High end programming environments such as the family of Microsoft Windows C development solutions offer far greater opportunities, but require much longer time for nonexperts to produce results. Especially for students who just want to visualise an effect which is needed for further studies the motivation to use simple easy and visual programming environments is very high. At the current stage of the mechANIma project we evaluate newer JAVA 114
intuitive and interactive way. It is even possible to use the whole system on a touchscrcen terminal without connection to a keyboard (all numerical input fields are accessible through a small calculator-like input control). In our laboratory one of these touchscreen terminals is available to the public 24 hours a day. Besides the animation systems students can access the whole mechANZma collection of electronic teaching materials like manuscripts, homework exercises, exams, etc. Also the latest news about lectures or additional events are accessible through these information systems which are connected to the university-intranet. The installation of such terminals was a very important milestone to accomplish a continuous access to media as mentioned in the first section.
Figure 4: Special animation systems for the caustic effect developed in the mechANIma project.
6. VIRTUAL LABORATORY As an additional way to illustrate complex mathematical derivations it is planned to prepare virtual views of the experiments. Figure 5 shows one such examples by using Apple Quicktime Virtual Reality to give students an idea of the real experiment. Our experiences show that students can understand the caustic effect (say) much better, if it is shown in a conspicuous manner. The Quicktime VR format allows in a relative simple way to create three-dimensional panoramic views by taking pictures of the real surrounding and the experiments.
Figure 3: Special animation systems for the caustic effect developed in the mechAMma project.
5. COMPUTER ALGEBRA SYSTEMS
Another important component of mechANZma is the integration of computfs algebra worksheets into the Rather complex Hyperwave information system. mathematical derivations are much easier to understand if it is possible to automatically plot functions and equations, modify parameters, or simply by changing a number. An example screenshot of the mathematical aspects of the “compressive edge load on a half plane” visualisation is added in Figure 4. Course materials contai!:ling computer algebra worksheets offer a great flexibilily due to the possibility of direct interaction. Therefore, the concepts of characterising individual learning as a self-organising process is achieved by enhancing the possibilities for the student to interact with the hypermedia system.
Figure 5: First impression of the virtual laboratory project..
7. CONCLUSION
As a conclusion, mechANZma is still under construction and will never enter a stage of being complete. The field of technical mechanics is much too complex to say that a hypermedia system and information systems holds all information and visualisations for the whole sector of mechanics. Additional animation and simulation systems
115
are still necessary. New technologies will lead to exciting opportunities for the future, and social embedding of hypermedia into learning processeswill always be a great challenge.
8. ACKNOWLEDGMENTS Our thanks go to the various students in our laboratory helping us to develop new materials for the mechANZ#ra project. Especially we would like to thank the developersof the miscellaneousvisualisation systems.
9. REFERENCES [l] K. Andrews, F. Kappe and H. Maurer, HyperG and Harmony: Towards the next generation of networked information technology, CHI’95, Denver, May 1995 [2] Brennecke, A. and Keil Slawik, R, Alltagspraxis der Hypermediagestaltung: Erfahrungen beim Einsatz des WWW in der Lehre. In Biicker, H-D.: SoftwareErgonomie’95 Mensch-Computer-Interaktion Anwendungsbereiche lernen voneinander, Teubner (1995). [3] Brennecke, A., Engbring, D., Keil-Slawik, R. and Selke, H., Das Lehren mit elektronischen Medien lernen - Erfahrungen, Problemeund Perspektivenbei multimediagestiitztem Lehren und Lernen. In: Wirtschaftsinformatik 39 (6), 563-568 (1997). [4] Brenneke, A. and Keil-Slawik, R., Notes on the Altagspraxis of Hypermedia Design. In: Maurer, H. (Ed). Educational Multimedia and Hypermedia. Proceedingsof ED-MEDIA 95, Graz, Austria, June 1721 (1995).
[51 Ferber, F. and Herrmann, K. P., Simulation von Versagensablaufen in faserverstkkten Verbundwerkstoffen. In: VDI-Berichte 73 1, 303-314 (1989) [61 Ferber, F. and Herrmann, K.P., Einsatz von Multimedia in der experimentellen Spannungsanalyseam Beispiel bruchmechanischer Untersuchungen mittels der Schatten- und Spannungsoptik, GESA-Symposium, lo.- 11. Oktober 1996, Schliersee. r71 Hampel, T., Analyse des Einsatzes und der Alltagspraxis von Multimedia in Forschung und Lehre der Technischen Mechanik - Entwicklung eines hypermedialen Animations-, Simulations- und Informationssystems -Diplomarbeit (HSII) filr den StudiengangInformatik, presentedfor review, Prof. Dr. Reinhard Keil-Slawik, Universitat- GH Paderborn, (1996). 181 Brennecke, A. and Keil-Slawik, R., Einsatz elektronischer Lehr- und Lernumgebungen in der Software-Ergonomie Ausbildung. In: Liskowsky, R., Velichkovsky, B. M. und Wiinschmann, W. (eds.): Software-Ergonomie ‘97 - Usability Engineering: Integration von Mensch-Computer-Interaktion und Software-Entwicklung. pp.83-92, Stuttgart: Teubner (1997). [91 Manogg, P.; Anwendungen der Schattenoptik zur Untersuchung des ZerreiSvorganges von Platten. Dissertation, Ernst-Mach-Institut, Freiburg, (1964) [ 101Radaj, D.; Zur Didaktik und Geschichte der Bruchmechanik. Materialpriihmg 12, Nr. 7, 236-237, (1970)
116
