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Virtual Laboratories as a teaching environment
A tangible solution or a passing novelty?
Jamie Robinson
Southampton University jmr399@soton.ac.uk
Abstract
Practical science is currently taught in a labor intensive, hardware dependent
fashion. Many of the traditional techniques could be embraced using existing
multimedia technologies, thus enabling self-paced, student driven learning. Here
we consider the role to be played by virtual laboratories. Virtual laboratories
allow students to simulate experiments that may require expensive or dangerous
hardware and materials from the safety of their PC. Virtual laboratories come in
a number of guises, ranging from screen-shot based applications (J C Waller, N
Foster 2000), to virtual reality systems driven by quantum mechanical theory (A
Suzuki et Al, 1999). The former aimed at teaching the usage of a specific piece
of equipment, the latter being a serious research tool.  
Recently virtual laboratories have gained press coverage (news.bbc.co.uk, 2001)
here they are described as "bring(ing) science to life". In this paper we explore
the various aspects of virtual laboratories, and how they can be applied to
teaching of undergraduates, Whether they can "bring science to life".
Classification of Virtual Laboratories
I will classify virtual laboratories into two main categories, depending on how they
gain their knowledge. One, has a limited set of facts inserted by the
programmer, this is the way that the majority of systems currently work. The
second, base their knowledge around a piece of far reaching piece of theory, this
allows a far wider range of experiments to be performed. 
The term Virtual Laboratory is also applied to projects that allow the remote
control of laboratory systems (K Keating et Al, 2000) but this is a topic more
suited to a discussion of network technologies. Online libraries of knowledge,
such as that at Imperial College (H Rzepa, A Tonge, 1998) are sometimes
referred to as virtual laboratories, but usually only as a component of a larger tool
set.
Virtual Reality techniques have been used to create interfaces to existing online
knowledge sources, an example of this is
http://www.sci.brooklyn.cuny.edu/~marciano a virtual environment that provides
hyper-links through interacting with it’s objects.
Fact Based Virtual Laboratories
Fact based virtual laboratories lend themselves best of supplementing traditional
experimental work. In their 2000 paper, Waller and Foster describe a virtual
instrument designed as part of a learning experiment. Their goal was to create a
system to teach people to use the spectrometer in their lab. The software was
then used at part of their undergraduate laboratory course. It is based around a
collection of web pages, which contain screen shots from the computer that
controls the spectrometer, along with still photos of the key steps of instrument
operation. The screen shots are linked using the 'Image Map' technique. This
allows different areas of the image to load different pages when clicked. This
gives the impression of operating the software.  The simulation allows students to
take measurements of a number of samples, as if they were operating the real
spectrometer. Some students were so convinced by the realism of the simulation
that they asked if the software "was somehow interfaced to the real
instrumentation" (Waller & Foster 2000). The simulator forms a safe
environment, that allows their students to learn to operate the equipment, without
the usual fears of damage attached to operating the real spectrometer. It was
noted anecdotally by faculty members, that equipment malfunctions, and
instances of useless data collection were considerably lower than in previous
years. The system they built was specific to that task, and as such is fairly
limited in what it can do. 
D B Armitage, 1999, created a more
wide ranging simulator for the same
experiment. This provided a simulation
whose results were calculated partially
on the fly. Waller and Fosters system
is limited to only those analysis that
they captured. Armitage's software
bases it results on data for a number of
compounds, and then produces
simulated output based on this. This
system also allows the user to adjust
the variables of the reaction in the
same way one would when running a
real experiment. It does however lack
the realistic interface provided by the
screen-shot example, its interface was designed for this application. It's purpose
is to help student to understand the procedure of the analysis, not the operation
of one specific spectrometer, and so it simplified interface is preferable,
highlighting only the more important controls.
Oxford University produced a virtual laboratory to complement their first year
undergraduate teaching (http://www.chem.ox.ac.uk/vrchemistry/). Their system
also falls into the fact-based category, but tries to be a bit less specific, allowing
more user control. In their system, a number of reactions have been filmed, and
you can call them up by selecting two reactants. After viewing the video clip, the
Screen Shots of Armitage's work,
(D B Armitage 1999)
user is quizzed about the reaction they've just created. This is again limited to
the reactions that you can perform, but is closely matched to the experimental
work performed in their lab, and is used as a re-enforcement tool. The use of
video clips gives the virtual situation a higher degree of realism. Video clips are
associated with reality, where as animations are perceived to be fake, although
they may be equally accurate. The use of this system benefits the user in that
they can repeat the reaction a number of times. Similar repartitions in the lab are
often limited for reasons of safety and cost. Equally in a virtual environment
potentially harmful reactions can be viewed many times, where as in a real lab
situation the reaction may require additional safety procedures which are
unavailable in a teaching environment.  
Derivation based Virtual Labs
Derivation based labs allow the user to extend the experiments beyond those
envisaged by the programmer. The results derived are based on solution of a
mathematical model of the situation. By producing results in this way they
extend their usefulness over fact based systems as they can be used to explore
new idea in a research situation. Work by Suzuki et Al (1999) proposed a
system that allows manipulation of virtual
materials at an atomic level. In real world
situations Eigler and Schweizer (1990)
produced the first documented evidence of this
(by spelling their sponsors name using xenon
atoms on a nickel surface) It is however a time
consuming work, limited to very small scales.
Hence the benefits of the virtual material lab
are obvious. In the VR environment, atoms
can be manipulated in much the same way as
macroscopic objects. However when the atoms are positioned, molecular
Screen Shot from the Oxford Virtual Laboratory
(http://www.chem.ox.ac.uk/vrchemistry/complex/default.html)
The result of Eigler and Schweizers
work moving atoms.
http://www.almaden.ibm.com/vis/st
m/atomo.html
dynamics theory steps in, and make the atoms behave like real atoms, in terms
of interatomic forces and interactions. This view of molecular manipulation was
popularized in the film Jurassic Park (Universal Studios, 1993) that shows
manipulation of a DNA strand in much the same was as Suzuki describes the
manipulation of atoms.  
Heermann and Fuhrmann (2000) use
a similar approach in their teaching of
classical mechanics. Their system is
based around a differential equation
solving engine. Users define objects
in their 'experiment' in terms of the
physical characteristics (mass, shape,
position) and their inter-connections,
either chosen from the library, or
created using simple java classes.
The use of this class based system,
allows the user much more freedom
to extend the calculations possible.
Once the system has been defined
the software calculates the
behavious of the system, then returns graphical schematic(s) of the system, and
results of the calculations either as text or graphical output. Previous software in
the same field (examples available from physicsweb.org) limits itself to specific
examples, with limited variables. By concentrating on specific systems, previous
simulators could use optimized, simplified equations to get results, but the
simplification limits their usefulness. It was noted that "the possibility to
investigate situations not foreseen by the teacher greatly boosts (student)
motivation" (Heermann and Fuhrmann, 2000) hence their work is at a clear
advantage. Their calculation system makes no attempt to run in real-time, hence
isn't limited to powerful workstation computers in the way that Suzuki's work is.
This opens the possibility for students to use the software from their own
computers as extension activities, which was found to further boost their
motivation.
Assessment of teaching
"Without assessment, there is no quantitative measure of student performance or
effectiveness of teaching" (R Allen, 1998) and here virtual laboratories borrow
techniques from Computer Based Teaching (CBT) Packages. By the use of
continuous assessment students and staff can be constantly updated with the
status of learning, if a topic isn't grasped then it can be repeated, or alternative
references provided. The benefits of repetition in the virtual environment have
already been mentioned. The Oxford University Virtual Chemistry Laboratory is
an example of this, after performing each reaction, users are taken through a few
multiple choice questions that prompt thought about the underlying theory, a step
The Physics Modeling Environment
Heermann and Fuhrmann 2000.
that is all to easy to overlook in the teaching laboratory environment where time
is often at a premium.
Virtual Laboratories have the added benefit that in the case of an error the worst
that can happen is a program crash, where as errors in a real laboratory can lead
on great expense, both in terms of man power, and repairs (J C Waller, N Foster
2000). This leads to a greater confidence in the student, as they have been able
to experiment and test ideas without the worry of breaking apparatus, "The first
time they were faced with any instrument, they were more worried about
damaging it or making a mistake, than leaning how to use it" (J C Waller, N
Foster 2000).  
It is noted that neither of the derivation-based simulators examined here provide
assessment. This is due partly to their wide range of possible experiments, and
also to their target being partially research related, as opposed to fact-based
simulators that are aimed directly at learning environments. Where these
simulators are used in a teaching environment they are used as tools to complete
a task, and hence are accompanied by a separate assessment scheme.
Technologies
Virtual Laboratories make use of a wide range of multimedia technologies, and
as examples of these we'll examine the 4 examples show here, The Gas
Chromatography-Mass Spectrometry (GC-MS) virtual instrument, Oxford
University Virtual Laboratory, the Virtual Material Laboratory, and the Physics
Modeling Environment.
The GC-MS Virtual Instrument makes use of an internet-based client/server
model. At the client end, it relies on the provision of a basic graphical web
browser, with the ability to display, and process image maps. At the server end it
uses a standard web page server. For realism it relies on a high speed, low
latency data link and as such was designed for on-campus use at Lehigh
University, PA. During its creation the use of streamed video was considered
over the use of static photo to demonstrate some of the apparatus handling
techniques. It was decided however that little was to be gained by such an
implementation, except for higher hardware and software requirements needed
to play the video files. The graphics used were gathered using a off the shelf
screen capture software, and instructive photos scanned using existing
hardware.
The Oxford Virtual Chemistry Laboratory follows a similar line in technological
requirements. The main difference being their inclusion of video files. They
choose the QuickTime format, for these, as the software to display these files is
freely available as a browser plug-in for the Macintosh and Windows platforms.
The author notes however that QuickTime isn't currently supported as a browser
plug-in on most UNIX platforms. The site also employs JavaScript to drive its
multiple-choice questions locally. Most modern browsers now understand
JavaScript, so this isn't a major concern. To provide more browser compatibility,
this marking could be moved onto the web server, however this may cause
excessive processor load, when compared to serving static pages. It was noted
that the quality of some of the video clips detracts from their view-ability, however
the questions that follow each clip often include detail of what was seen. This is
partly indicative of the sites age and the current technology when it was
produced, however the task of updating the video file to use a more loss-less
compression technique would be a significant task, with relatively little gain.  
The Virtual Material Laboratory (VML), employs a distributed computational
system, but for reasons of performance, as opposed to multiple user access.
The VML is split across 3 servers, with a 4th system providing overall control.
The reason for this being that it was realized that the molecular dynamics
calculation were very intensive, and that the 3-D graphical representation
calculations being similarly intensive. Hence
as their goal was to provide a near real-time
interface these two processes were split
between two dedicated systems, one
dedicated to the theory calculation, and a
graphics workstation to render the interface.
User control of the system was provided
using a force-feedback system, which allows
the user to manipulate the simulated atoms
in a virtual 3-D space. As additional
advantage of such a system, advances in
say graphics performance can be handled by
replacing only the graphics server. Likewise
more complex simulations can be handled by the use of different server
hardware. In the test performed by Suzuki et Al, they limited the simulation to a
small atom set, and disabled the force-feedback system. This allowed the
simulation to be run from a single workstation. It was noted, that under these
conditions they produced adequate real-time output, but that for a more
significant number of atoms or real-time force feedback greater computer power
was required, and it was planned to extend the software so the simulation server
could be run on a parallel supercomputer.
The Physics Modeling Environment, is a standalone java application, hence
should run on a wide range of platforms with little modification. The software can
be extended by writing part classes, 'the user simply has to define the
parameters, and the number of connectors for the new part class' 'thus the user
benefits from a ready-made piece of software with an intuitive GUI that can be
extended rather easily beyond the predefined scope' (Heermann & Fuhrmann,
2000). The greatest strength of this implementation, its generalization, is also it's
weakness, in that in all bar the simplest cases the time taken to solve the
differential equations is significant, and hence the software makes no attempt to
do this in real-time.
Summary
Virtual Laboratories borrow technologies from a wide range of fields. They
extend to include a wide range of systems, from simple textual interfaces through
to 3-D virtual reality environments, which try to mimic real-life. The exact design
of a particular system is dictated by its target audience. If one is designing a
system to teach the operation of a particular piece of equipment, then the closer
that the simulation can mimic the real-life device the better. In the modern world
of computer-controlled laboratories, these will typically mimic the lab computer,
and provide instrument feedback both through the usual interface software, and
also through the use of video clips and animations. Virtual systems allow
students to perform repeated experiments, which they may be unable to perform
in real life. In this way these systems can form an important part of a traditional
course, but shouldn't be seen to replace real-life laboratory work. They can
precede real work, and in these cases it has been seen that the preview they
provide can improve safety and the quality of results returned. Virtual
laboratories are also used to perform experiments that aren't currently practical,
and return results based on theoretical calculation. Providing a virtual reality
interface to these calculations allows then to be visualized in a way that may
expose other ideas or facets that hadn't previously been realized. These
visualizations can also be used to explain theories in a teaching environment;
most lecturers find it hard to represent 3-D space on a blackboard, however 3-D
computer environments provide a representation that can be explored in real-
time.
Current virtual laboratories provide a important extension to current learning, but
as such they should not be expected to replace the learning experience of real-
life laboratory work. It is likely that virtual environments in general, will become
an important part of teaching as stricter safety controls are placed on the range
of experiments that can be carried out.  
Thanks
D Bruce Armitage (Thiel College, Greenville, PA), Natalie Foster (Lehigh
University, Bethlehem, PA) for making their software available to me.
References
R Allen,
The Web: interactive and multimedia education. 
Computer Networks and ISDN Systems, 30, 1998, 1717-1727
D B Armitage,
A GC Instrument Simulator
Journal of Chemical Education, 76.2, February 1999, 287
D.M. Eigler, E.K. Schweizer.
Positioning single atoms with a scanning tunneling microscope.
Nature 344, 1990, 524-526
D W Heermann, T T Fuhrmann
Teaching physics in the virtual university: the Mechanics toolkit
Computer Physics Communications, 127, 2000, 11-15
K Keating, J Myers, J Pelton, R Bair, D Wemmer, P Ellis,
Development and User of a virtual NMR Facility,
Journal of Magnetic Resonance, 143.1, March 2000, 172-183
H Rzepa, A Tonge
VChemlab: A virtual chemistry laboratory.
Journal of Chemical Information and Computer Science, 38, 1998, 1048-1053
A Suzuki, M Kamiko, R Yamamoto, Y Tateizumi, M Hashimoto
Molecular simulations in the virtual material laboratory,
Computational Materials Science, 14, 1999, 227-231
J C Waller, N Foster,
Training via the web: a virtual instrument,
Computers and Education, 35, March 2000, 161-167
Internet References
www.chem.ox.ac.uk/vrchemistry
Oxford University Virtual Chemistry Lab
news.bbc.co.uk 2001 
BBC News Article - Virtual Lab brings Science To Life
http://news.bbc.co.uk/1/hi/sci/tech/1111654.stm
physicsweb.org
Virtual Interactive Experiments
http://physicsweb.org/resources/Education/Interactive_experiments/
www.sci.brooklyn.cuny.edu/~marciano
Virtual Multi-Media Internet Laboratories
Access to web pages through a 3D, VRML environment