DOI: 10.2478/V10051-008-0025-3 Implementation, Effectiveness and Experience With Remote Laboratory in Engineering Education Andreja Rojko, Matjaž Debevc, Darko Hercog Fakulteta za elektrotehniko, računalništvo in informatiko, Univerza v Mariboru, Smetanova 17, 2000 Maribor, andreja.rojko@uni-mb.si, matjaz.debevc@uni-mb.si, darko.hercog@uni-mb.si Modern educational methods bring many new challenges from the pedagogical, as well as from the technical aspect. One of the more significant is the integration of information and communication technology into the educational process. These is particularly noticeable in the engineering education where the requests of the industry for a faster and more efficient acquisition of knowledge and practical skills lead to a constant search for new solutions in the learning process which would attract and motivate students, as well as be user friendly. This is especially difficult to be reached with the practical education which is usually composed of laboratory exercises that are bound to a specific time and place. One of the possible solutions are the remote laboratories which offer the possibility of the implementation of real remote laboratory experiments in the educational institutions' laboratories and, therefore, enhance the students' knowledge and capability for dealing with some technical problems without the need for their physical presence in the laboratory. In the article, the example of a successful implementation of the remote laboratory in the field of engineering, developed and operating in the Moodle environment, is presented. The laboratory does not only represent the framework for the experiment implementation, but it also offers courses with complete documentation, therefore courses can be performed on distance. As an example, the case of the most widely used course from remote laboratory is presented, i.e., the "Control of nonlinear mechanism" course. Special attention is given to the description of the booking process for remote experiments, the execution of remote experiments and the applied user interface. The evaluation of the interface usability from the point of view of end users was performed via the acknowledged SUMI method. Additionally, another questionnaire was prepared in order to investigate the students' opinion about working in the remote laboratory. The results have shown that the presented remote laboratory is user friendly and accepted by both teachers and students as a suitable and interesting supplement to the conventional laboratory exercises. Key words: Remote laboratory, Mechatronics, Usability evaluation. 1 Introduction Due to the increasing use of information and communication technology (ICT), modern educational processes bring numerous changes in all areas. These changes are also visible in the fact that we are ever more willing and fast in our transition from the traditional learning to e-learning. E-learning represents the integration of the use of multimedia tools, as well as web media and communication tools (Downes, 2005). Moreover, a transition from traditional learning to constructivistic learning (Huitt, 2003), as well as finding solutions for problems where the importance of the students' own researching and designing their knowledge with practical work, followed by the group discussions of the problems and learning by doing is increasing (Costa et al., 2007; Alterovitz and Ramoni, 2007). In this way the students are learning to manage and solve complex problems from various perspectives. One of the most important aspects of the designing of a quality study process in the field of technical engineering education is adequately prepared and designed laboratory work. Especially the industry expects from the educational institutions that the students will in the course of their studies gain practical experience by using the systems they will be later on operating with, especially due to the pressure of the market and a fast development of engineering (Äström, 1994). For this purpose, the educational institutions prepare laboratory exercises in such a way that the students have the chance of gaining knowledge by working on experiments and systems and performing the analyses by themselves, (Bauer et al., 2007). Such laboratory work with concrete experimental devices demands time and physical presence of the students, as well as of the teaching staff. Moreover, suitable adjusting of dates for the live performance of laboratory exercises is necessary. This can be particularly difficult, especially with larger classes of students. Furthermore, the preparation of suitable laboratory experiment for larger classes demands greater financial investments (Nedic et al., 2003). To solve the problems of live laboratory exercises at an educational institution, a need for offering the students additional possibilities for acquiring knowledge of experimental systems outside the real laboratory, i.e., without their direct physical presence, is visible. Thus, the following approaches, which are supported via the World Wide Web, are increasing in use (Bencomo, 2004): ■ videos of exercise implementations, ■ virtual laboratory experiments and ■ remote laboratory experiments. Despite the constantly increasing popularity of the video in the World Wide Web, the video lacks interactivity and it is for this reason that the students cannot get practical experience, but only the basic insight into the exercises. The other alternative is virtual laboratories which offer simulation environments. These environments offer the chance that the students familiarize themselves with the theoretical aspects and perform experiments in a certain interactive virtual environment that can be two- or three-dimensional. Although virtual laboratories can be quite attractive (e.g., Boeing 777 flight simulator) (Trego, 1995), they are only a poor substitute for practical work on physical devices, because simulations cannot include all the aspects of the real world. For this reason, remote laboratory experiments which offer practical work on real devices on distance are increasingly being introduced. Among the first remote laboratories were the laboratory experiments in robotics (Taylor and Trevelyan, 1995) and system control (Bohus et al., 1995). For a certain institution, especially in the case where the institutions are cooperating with other institutions in the preparation process of the laboratory experiments, this means fewer investments into the necessary technology. On the whole, it is being ascertained that planning and development of remote laboratory experiments which are included in the direct environment of e-contents is not a simple process. The materials and equipment, as well as the interaction have to be adequately planned, elaborated and evaluated for their usability. In our research, we wanted to find the answer to the question of how to design remote laboratory experiments so that they are going to be an efficient replacement of real laboratory exercises. Thus, we were focusing on the following aspects: ■ the explanation of the remote laboratory experiment implementation and its learning objectives on an example of nonlinear system control in the field of engineering, ■ the explanation of didactical experience in working with the students on distance where it was established how the students accept remote laboratory experiments in comparison with real experiments in the laboratory, ■ the description of the usability evaluation of the system for remote experiments which was done via the standardized method SUMI. 2 Implementation of remote exercises With distance education, there are, from the perspective of teaching methods, various chances of the implementation of remote exercises, such as individual approaches, approaches one-to-many and approaches many-to-many (Cohen et al., 2004). Individual methods, among other things, include the implementation of interviews, preparation of seminar papers, implementation of various e-contents and other forms where the students perform the tasks individually. The methods one-to-many with distance education usually include the presentation of the assistant with the aid of videoconference, streaming video or webcasting (Reynolds et al., 2008) and lately also with hypervideo technology which enables interactivity within the video (Debevc et al., 2008). With the method many-to-many, we are dealing with discussion groups, debates, simulations, case studies and project work. Due to the extreme development of the ICT, it is today possible to enable the students a high degree of interactivity and cooperation with the implementation of remote exercises without the physical presence. Despite this, the social contact can be maintained with the aid of adequate communication and remote discussion tools. Nowadays, computer technology offers (Bencomo, 2004): ■ better human-computer interaction, ■ more natural and intuitive graphical user interfaces, ■ high degree of interactivity, ■ access to remote computer applications. In the field of engineering, it is important for the students that in their studies and exercise implementation they get acquainted with the physical laws that describe the operation of these systems. Scientists and engineers usually use computers for calculating and graphical imaging of the responses of these technical systems onto various initial states and inputs. With technical systems, we are thus tackling time responses, spectra, Bode and Nyquist diagrams, etc. The knowledge and comprehension of these basic system descriptions represent one of the important aspects for the comprehension of the operation of technical systems. The development of ICT and distance education have thus provided the students the chance to get acquainted with technical systems according to an individual didactical method in the World Wide Web and to perform remote exercises independent of time and place, so that they the students are performing the experiments and solving problems. Didactically speaking, it is about the principle of problem learning and learning by doing. These are student-oriented learning processes where the teacher is not in the main focus, but on the side and intervenes only when necessary. Didactically speaking, the use of remote laboratories provides the students with the access to experiments 24 hours per day and from any location whatsoever. An even greater advantage for the students is that they can, if they want and understand it, perform the exercise quickly. On the other hand, they can also take some more time and repeat the exercise in a greater detail with the goal of improving their comprehension of the system operation and its reactions if they find it difficult. By this, the learning process is improved, because there is constant link between the theory and practice, so that the students on real devices examine theoretical bases and gain the necessary practical experience and skills which are fundamental in the engineering studies. On the other hand, remote laboratories and the implementation of remote exercises offer an equal inclusion into the learning process also to the persons with special needs. In this way, better position in the modern, technologically-driven society is enabled for them. 3 Remote laboratory for automation and mechatronics As an example, we will present a remote laboratory which is intended for the students in the field of automation and mechatronics and which was constructed at the University of Maribor, Faculty of Electrical Engineering and Computer Science (Hercog et al. 2007). The purpose of the remote laboratory is offering students and lecturers an alternative way of implementing the regular learning process or for its supplementation. In the framework of the remote laboratory, there are more extensive courses at disposal and they cover the basic theory from the field of operation, modeling, simulation, control, design and implementation of electrical and mechatronic device. The courses, which demand on average 50 hours of intensive work from the students, are practially oriented. Focus point of every course are remote experiments. The web portal of the remote laboratory was designed and constructed in the framework of the Moodle webcasting tool with which the user management and the inclusion of the web learning materials were facilitated (Brandl, 2005). The access to the contents of the remote laboratory is enabled only for registered users. The registration is free of charge and it is possible to register right on the web portal of the remote laboratory. All the data and necessary documentation are at disposal in Slovenian, as well as in the English language which enables the use of the laboratories to foreign students, as well. The basic, introductory website is designed in such a way that it offers the users by entering into the system Figure 1: Introductory website of a remote laboratory all the necessary data about the laboratory, this being the description of the remote laboratory, the possibility of logging into the system and the necessary data for the implementation of exercises in the private environment (Figure 1 - functions of the remote laboratory). Additionally, the programs which the students must download on their own computers are also at their disposal. These are the programs which are necessary for the operation of the LabVIEW environment and for the video presentation of remote experiment. 3.1 Remote laboratory architecture and principle of operation Remote laboratory is composed of the laboratory server, DSP-2 control systems and several objects under control (Figure 2). DSP-2 control systems are connected to the lab server which is, in turn, connected to the Internet. Embedded control systems execute predefined control algorithms and through the analogue and digital I/O signals drive the real process (DC motor, nonlinear mechanism, SCARA robot). At the same time, data visualization and parameter tuning program is running on the lab server. This program receives selected data from the control system and displays them in the experiment graphical user interface (GUI). Each experiment GUI also contains controller parameters which can be changed on-the-fly by the user. On each value change event, new parameter value is transmitted to the control system. Experiments GUI, which are created using LabVIEW, are further published on the Web using a LabVIEW built-in Web Publishing Tool. Once the GUI is published, anyone on the Web can access and control an experiment using the standard Web browser. Two additional servers are also running on the labs server: (1) Web server and (2) visualization server. The first one is responsible for displaying remote laboratory web pages while the latter enables live video broadcasting. Visualization solution is based on client-server architecture (Gergic and Hercog, 2006). Server applica- tion grabs the images from FireWire cameras, located inside the remote laboratory, and sends JPEG (Joint Photographic Experts Group) compressed images to the client application which decompresses and displays the received images to the remote user. 3.2 Courses in remote laboratory When the student logs in the system, groups of courses appear. For each course, adequate documentation is prepared in the remote laboratory, as well as remote experiments. In the documentation, all key data for teachers and students are stated, together with those that are necessary for the informing about the course and for a successful implementation of the course. Inside a specific course, the following is at the ones' disposal: Course Overview, Course Objectives, Documentation, Execution, Authors, Poster, Photo Gallery and other materials. In the "Course Overview" section, the data of the course, the necessary entering conditions, the structure of the course and the evaluated time demandness are stated. The description of the course includes a short summary of the course and a description of the main chapters. Its basic purpose is to provide the user with a basic description in a few sentences. The necessary entering conditions include the description of the necessary knowledge which are the basis for the comprehension and implementation of the course. The conditions are stated as concrete conditions in the sense of the knowledge which is required. Thus, the knowledge of, e.g., physics at the high-school level can be required, the knowledge of the linear algebra basics, etc. Also the requirements concerning knowledge of programming in specific programs are stated here. The course structure shows logical units or modules which the course is composed of. Usually, one logical unit corresponds to one chapter in the documentation. The structure of the course is sometimes presented in the graphical form, so Figure 2: Block scheme of remote laboratory that it is visible how the individual modules are combined and in what order they can be performed. Time demand-ness defines the necessary average time for each logical unit or module of the course, as well as the total time which is needed for the entire course execution. In the "Course Objectives" section, course objectives are concisely stated, together with the expected learning outcomes and the suggested method of achieving the desired learning outcomes. The expected learning outcomes relate to a gained knowledge or skills, while the suggested method of achieving the learning outcomes describes the related procedures. In the "Documentation" section, all theoretical background of the course is stated, together with the necessary literature for additional studying. The theory is combined with the exercises for students which can be theoretical, computational and simulation exercises, or remote experiments. With each task, it is specifically stated what the task of the student is and what results, together with their comments, must be in the report which the students should provide their mentor with. Furthermore, there is also documentation for the teacher at disposal. Besides the key to the exercises, it also offers advice on how to include the course into the study program, as well as the description of the most common problems that appear with the practical implementation of the course. This documentation can be provided on a specific demand from the author of the course and is not posted on the website of the laboratory. In the "Implementation" section, all the necessary data which are needed for the practical implementation of remote experiments are collected. Besides the short description of the experiments and the instruction for the implementation of experiments, also the necessary software, is available (See Figure 3). On the website, there is also the link to the booking table for the reservation of dates of the remote experiment implementation (See Figure 4). With the aid of this table, the users can make a reservation of a date which suits them best for the implementation of the remote experiment. The booking table is one of the most important elements for a successful use of the remote laboratory, because it regulates the access to the experiment in such a way that only one user can use it on the reserved date and time. The user simply clicks on the desired date and time and the colour of the date and time change, adequately. Those, marked in green, are still free, while those, marked in red, are occupied. Course Contrc»! of nonline^rmechanism ' WindcKvs Jnterret Explorer ^^^^ T |?Vl hittp://rerriQMBb.r&.feri,uni-mb.si/courje/view.php?id=6&i«^ ^ iF^"?^ ifnCoufi« Control of nonlifiMfmecharkism | ] ^ ^ ' 0 ' P^ge ' Toofe » -^ Faculty af ElBccrical Engineering and Computer Science DSP-based Remote Control Laboratory Home Control of nonlinear mechanism Vou ar« logged in as Student Return to my normal role Course Menu Control of nonlinear rrn ^^ Course overview ^^ Course objectives Doc LI mentation ^^[Execulionl Q Poster Auttiors Participants Administration Si] Unenroi tne from Control of nonlinear met nanism Control of nonlinear mechanism Execution In this expenmem it is possible to test efficiency of different motion controllers wnen controlling mecnanism with nonlinear dynamicMechanism, shown on pictures below, is driven by DC motor ESCAP 219P (12 V) with ircrementa! encoder. As a controller DSP-2 control system is applied Three motion control algorithms are implemented In remote laboratory; • Cascade corrlroller composed from P position controller, PI velocity conlmller, PI current controller. User can tune parameters of position and velocity controller. • Computed torque controller. Position and velocity gain are tunable Inner nonlinear loop can be disabled • PD controller with position and velocity feedback loop (the controller is available as sub option of computer torrjue controller). Position and velocity gains are tunable. Some signals are presented in graphs ; user can observe actual and reference position, position error and actual and reference cunent. Other signals can be monitored numerically IH/IPORTANT! For the execution of the remote eitperments LabVIEW Rutx-time Engine must be installed on computer Additionally, for transfer of live picture Webcam client program is required ■ Runfbook this experiment http://reTTKrtelab.rct.reri.un i-rrb.5l/rnDd/boDkrng/view.php?id=87 9 Internet | Protected Mode: Off Si IOC* T Figure 3: Implementation of a remote experiment, website ^ Control of nc^nlinear mechanism: Booking - Control of nonlinear mechanism - Wiidows internet Explorer □d® * jifln http://remotelab.ro.feri.tfii-fr4).si/mod/booJ^ng/view.php?kJ=87©tirnesl(3t= 1 d pRli Uit v^ Fj^tes lools Heb Tn Control of ncrJinedr mechtfwm: Goolir>g - control of A ■ ' 0 A* ' iiä'Eäy« ' ^Ta* . O Booking - Control of nonlinear mechanism 27.5.2008 - 2.5.2008 A Server time reported t» tocal time Eone : 30. Mav 2008 10:05:19 Server tirne: SO. 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