activities, the use of two tutorials has resulted in a very effective tool for the
students not only to grasp the theoretical concepts of technical drawing but also
to.
Enhancing Visualization Skills in Freshman Engineering Students I. E. Esparragoza School of Engineering Design, Technology and Professional Programs Pennsylvania State University , 25 Yearsley Mill Rd., Media, PA 19063
ABSTRACT - Engineers are required to have a high
volume and size that can be sketched for further
level of visualization skills necessary in the design
analysis. As shown in Fig. 2, the design ideation
process and in the solution of engineering problems.
requires visual analysis and synthesis.
However, many of the freshmen engineering students have problems in processing and understanding visual information or in developing mental images. Due to this fact, the freshman engineering design and graphics course offered on this campus has been structured to expose the students to a series of problems, activities and exercises that assist them in developing and enhancing their visualization skills. Among these activities, the use of two tutorials has resulted in a very
Fig. 1 Role of graphics in the solution of engineering problems
effective tool for the students not only to grasp the theoretical concepts of technical drawing but also to enhance their ability of processing and synthesizing visual information. I. Introduction The study of engineering requires from the students the ability to process visual information and the ability to create mental images of existing objects or objects to be developed. Both abilities are necessaries in engineering. The use of graphics to represent quantities and solve problems, which is a common practice in engineering, implies the ability to model graphically and/or understand the graphical representation of the
Fig. 2 Fundamental role of visual thinking in the design ideation
problem. Classical examples are the use of vectors to represent quantities and the use of free body diagrams in the analysis and solution of engineering problems as
Creativity and innovation in design requires a high
shown in Fig. 1. In the design process, the ideation
level of imagination and it is evident that imagination is
implies the ability to create mental images of objects or
close related to the mental process of generating and
mechanism resulting in a mental picture with form,
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processing ideas and images. Great designers and
freshman engineering design and graphics course
inventors have used the combination of drawings and
offered on this campus has been structured to expose the
imagination to develop magnificent ideas. Many of
students to a series of problems, activities and exercises
these ideas have evolved thanks to designers with
that assist them in developing and enhancing their
amazing visual reasoning skills. All human beings have
visualization skills. The use of two tutorials: Visual
the ability of process visual information the same as all
Reasoning Tutor and Orthographic Projection Tutor,
human beings have the ability to walk. There are some
developed by Professor Yong Se Kim at Sungkyunkwan
people who can run faster than others the same as there
University, Korea, has resulted in a very effective tool
are some people who have the ability of processing
for the students not only to grasp the theoretical
visual information better than others. If practice can
concepts of multiview drawings, and axonometric
allow some people to run faster than others, similarly,
drawings but also to enhance their ability of processing
practice can allow some people to process visual
and synthesizing visual information. These tutorials
information better than others. The difference here is
provide the students the opportunity to solve graphics
that one requires physical training and the other one
problems interactively using solid modeling and
requires mental training. The ideal situation for
computer animations allowing the students to visualize
engineers is not only to process the visual information
in a very effective way the relationship between the
fast but to enhance visualization skills to be used in the
solid object and its projection in the two dimensional
design process and in the solution of engineering
plane.
problems. Enhance visualization skills means to improve the ability to process and interpret visual
II. Engineering Graphics and Visualization
information and to generate visual ideas that can be
Giesecke et al (2004) define visualization as the
transformed into concrete drawings and objects.
ability to study the views of an object; Bertoline and
Engineers, designers and scientists should have visual
Wiebe (2003) describe visualization as the ability to
abilities above average people to be creative and
process and interpret 3-D objects and sketch them in a
resourceful professional.
paper. They also recognized the importance of
However, many of the freshman engineering
visualization in the design process. It is clear that most
students have not had the opportunity to develop the
of the authors in engineering graphics associate
visualization skills necessary in engineering. They have
visualization to the ability of processing and interpreting
problems in the representation of a three dimensional
the visual information of a 3-D object and the study of
space in a two dimensional plane or visualizing a two
its projected views. Based on these definitions and
dimensional drawing as a three dimensional solid
recognizing the necessity of enhancing visualization
object. This problem has been addressed in many
skills in the engineering students, the freshman
engineering graphics textbooks but it probably does not
engineering design and graphics class is the perfect
have the necessary attention in the classroom. It is
course to start exposing the students to the visual
important to emphasize that poor visualization skills in
thinking process. Visualization is a mental process that
engineering represent problems for the engineering
requires practice rather than theoretical definitions.
student in many courses and problems for the engineer
Therefore, the training to help the students to develop
in his or her future performance.
and enhance their visualizations skills can be done by
Due to this fact, the
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means of problems and exercises in the orthographic
physical models is always a good option since they
projection and axonometric drawings topics. These
allow the students to use the five senses with the model.
basic topics provide the elements to visualize a 3-D
However, time and cost building the object make those
object, to synthesize or have a mental image of the
models no efficient. With the new technology and the
object and draw the image in terms of views or
use of computers and multimedia programs, in the
isometric drawings.
freshman engineering graphics course, the use of
In the freshman engineering design and graphics
physical models to show objects has been replaced by
course taught in Penn State Delaware County campus,
the use of multimedia tutorials and complemented by
students are required to sketch multiview drawings and
the use of solid modeling using AutoCAD and
isometric drawings using instruments and AutoCAD.
SolidWorks, where complex objects can be analyzed
They are also exposed to two design projects during the
and created efficiently.
semester and the first one requires the multiview
III. Multimedia Tutorials
drawing of the structure and the second one requires
The use of computers and multimedia systems has
multiview drawing and solid model drawing. Besides
become very popular. Multimedia system is considered
that, some simple exercises and design problems are
a computer-based communication system as defined by
solved by the students in the classroom during the
Burleson, et al. (2001) that includes the use of text,
semester. The primary goal of the class and of each
audio, video, graphics and computer animations. The
exercise is to provide the necessary practical training for
use of multimedia software is becoming very important
the student to develop and enhance visual reasoning that
in the learning process. Therefore, the integration of
they can apply later in other courses and the career.
classroom lectures and multimedia tutorials provides
However, it was found that even though the
not only the theoretical foundations but also the visual
exercises across the semester, many students still had
component for the engineering problems that help the
problems visualizing 3-D objects from the principal
student to grasp the concepts and enhance their
views or sketching the views from the volumetric object
visualization skills.
at the end of the semester. One of the reasons for this is
Poli et al (2003) have shown that multimedia
that most of the problems, as presented in the textbooks,
tutorials are an effective learning tool. They have all the
are in the 2-D plane format of the book. It means those
necessary features for a pleasant and effective learning
students having problems at the end of the semester
experience. In a multimedia tutorial text, audio, visual
need a level of visualization skills which has not been
effects, videos, pictures, and animations might be
reached at this stage and using the traditional format in
integrated in a single program allowing the tutorial to
the classroom. Therefore, it was necessary to introduce
present the topics and support them in a very
more visual aids and exercises to assist the students to
resourceful form. This makes the multimedia to differ
guarantee at the end of the semester a reasonable level
from the traditional textbooks. Books present the
of visualization skills for all the engineering students.
concepts with inanimate text and figures while the
The use of visual aids in the learning process has
computer-related tutorials are dynamic pages containing
been recognized by many educators and researchers as
audio, video and graphics animations. In technical
can be seen in Juarez-Espinosa et al. (2000), Lowrie
drawing the computer graphics animations are a
(2002), Les and Les (2003) among others. The use of
powerful instrument to exercise the visual thinking
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without necessity of using physical models. Besides,
“sweeping operations” available in the program are
multimedia tutorials can provide immediate feedback to
listed under the “action” button in the pull-down menu
the user.
at the top of the screen. The sweeping operations
Due to the necessity of providing more and better
command can also be invoked by clicking the right
exercises to the student and taking full advantage of the
button of the mouse. The first step consists of selecting
new
were
the “sweep face” option from the menu. Then, the edges
introduced in the freshman engineering design and
forming the face are selected by clicking them with the
graphics course to complement the traditional lecturing
mouse. Once a close contour of a feasible face is
and exercises in the classroom: the Visual Reasoning
completed the face is entirely defined by clicking the
Tutor (VRT) and the Orthographic Projection Tutor
center button of the mouse. The sweeping operation can
(OPT). Both tutorials were developed by Yong Se Kim
be performed by dragging the face with the mouse until
at Sungkyunkwan University, Korea.
the face is aligned with an edge in the corresponding
technology,
two
multimedia
tutorials
Visual Reasoning Tutorial (VRT). This tutorial
projection plane. Once the operation is completed the
consists of fourteen missing view problems. Here,
face of the solid is in place as revealed in Fig. 3(b) that
students have to construct a solid model from the two
shows a partially completed solid model. The operation
orthographic projection views given by means of
is repeated for all the faces that can be swept. Edges and
sweeping operations which are the reverse procedure of
vertices can also be swept to complete the inclined and
orthographic projection. Only two principal views are
oblique planes: edges are swept to complete inclined
given; therefore, more than one solution is possible in
surface, like the one to be completed in Fig. 3(b) where
some of the problems. Students are instructed to
first the face is swept and then and edge is swept to
determine if more than one solution is feasible and to
complete the inclined face; vertices are swept to
find all possible solution. This exercise will help them
complete oblique planes. Those faces that cannot be
to practice the visual reasoning. These missing view
completed by sweeping operations can be finished by
problems are designed for the student to complete the
using the “construct” command in the “action” button
visual thinking process depicted in Fig. 2: visual
after all the sweeping faces are in place. In this case, the
analysis by seeing the given views, visual synthesis by
edges for the face to be constructed are selected after
imagining the object, and visual model by drawing the
the “construct” command has been invoked. Users can
solid model. This tutorial provides assistant to the
have immediate feedback after each sweeping or
students during the solution of the problem; therefore,
construction operation by activating the “teacher”
they can check their progress at any stage and determine
window. If the operation performed generates a feasible
if
face, this face will appear green in the teacher window;
the
sweeping
operation
performed
(inverse
if the operation performed generates a partially correct
projection) has produced a feasible solid face.
face, this face will appear yellow in the teacher window;
Figure 3 shows one of the problems available in the
a wrong face will appear red in the teacher window.
VRT tutorial. 3(a) shows the statement of the problem. A solid model is to be constructed using the given top
Orthographic Projection Tutor (OPT). This
and front orthographic views. To construct the solid
tutorial consists of 32 sets of problems each of them
model, faces are to be defined and then swept to the
with more than one exercise involving orthographic
right position in the solid model. The different
projections concepts. The software is designed for the
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students to start solving problems at the highest level. If
starting in the highest level, students are instructed to
the students have difficulties solving the problems at
start from the lowest level and move up once they have
this level the software leads the student to a lower level
solved all the problems in each level. This practice
where he or she can solve simpler problems and review
allows the student to reinforce the concepts and being
the concepts needed for the higher level. The tutorial
better prepare for the higher level problems. Students
uses a learning network where the concepts and
are instructed to move across the learning network so
problems are related and linked according to the
they can choose the level and problems they want to
definitions and concepts in orthographic projection;
work in at any stage. This permits the students to
therefore, students having problem at any level are sent
advance at their pace. In any case, the tutorial keeps the
through the learning network to review the problems
ability to “evaluate” the performance of the students and
and concepts needed for the problems at higher levels.
send them back to a lower level if they do not solve a
Even though the tutorial was designed to start solving
problem properly. The greatest feature of this tutorial is
problems at the highest level, the tutorial has been
the relation between the concepts, problems and
introduced in the freshman engineering design and
graphics animations. Each level contains a good set of
graphics course not only for the student to solve the
problems which are always complemented with a three
problems but also for the instructor to present the
dimensional animation.
concepts for multiview drawings. Therefore, instead of
Fig. 3 Missing view problem partially solved using the VRT tutorial Figure 4 shows a typical problem in the OPT.
observed that on the left side, the solid model is
The example shown belongs to the highest level
shown and this can be moved, rotated, panned,
(level 0) and is identified as Problem 1-AF. It is
zoomed in and out similar to the actions that can be
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performed in any CAD software. On the right side the
by clicking the check button. This action also causes
statement of the problem is given with the space to
the “solution movie” window appears and from here
provide the answer. On this example four faces are
the animation movie showing the projection of the
highlighted, one at a time, and the user should
highlighted face can be played. It can be seen that the
identify the face number in the multiview drawing
animation has four options; therefore, the user decides
shown. The user can check the response immediately
which projection he or she is interested in reviewing.
Fig. 4 Orthographic projection problem using OPT tutorial IV. Conclusion
Most of the students have learned how to use the
The use of VRT and OPT tutorials has replaced
tutorials very quick and only few of them require
the used of physical models in engineering graphics.
additional assistance from the instructor for an
Both tutorials have been used effectively to teach the
effective use of the instructional tutorials. Even
orthographic projection topic and the “glass box”
though some students have had previous classes of
concept which is one of the most critical issues in
technical drawing in high school and the others have
technical drawing. Besides that, both tutorials provide
no previous experience, the entire class have adapted
a good number of exercises for the student to practice
to the programs easily since the tutorials include
and enhance their visualization skills. It is through
problems ranging from very basic ones to more
practice that students can improve the ability to think
complex and challenging problems. Therefore, the
in three dimensions and draw in a two dimensional
variety and level of problems are adequate for any
plane. This mental exercise will enhance the
stage of technical graphics knowledge
visualization skills necessary in engineering.
Students have shown that they enjoy the interaction with the tutorials and learn visualizations
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VI. References
skills while they are challenged to solve the problems. The immediate feedback makes the whole practice a
Bertoline, G.R. and Wiebe, E.N. (2003). Technical Graphics Communication, New York, NY: McGrawHill.
learning experience rather than an evaluation process. The tutorials have solely been used for the students to study, practice and learn but not as a grading tool.
Burleson, W., Ganz, A., and Harris, I. (2001). Educational innovations in multimedia systems. Journal of Education, Vol. 90, No. 1, pp. 21-31.
This is an effective way of removing the grade related pressure so students have the benefits of learning
Giesecke, F.E., Mitchell, A., Spencer, H.C., Hill, I.L., Loving, R.O., Dygdon, J.T. and Novak, J.E. (2004). Engineering Graphics. Upper Saddle River, NJ: Pearson Prentice-Hall.
while playing. The use of traditional lectures and hand drawing exercises is still a fundamental part of the course. The tutorials have come to reinforce the concept taught
Hubbard, C., Mengshoel, O.J., Moon, C., and Kim, Y.S. (1996). Multimedia instructional software for visual reasoning: Visual Reasoning Tutorial (VRT). Proceedings Int. Conference on Multimedia Computing and Systems, pp. 261-268.
using the traditional methods. The use of some simple physical models and exercises does not necessary have to disappear from the classroom. The idea is to integrate all the tools available0020to ensure students
Juarez-Espinosa, O., Hendrickson, C., and Garrett, J. (2000). Using visualization for teaching. Proceedings of SPIE The International Society for Optical Engineering, v 3960, pp 86-95.
have the opportunity to exercise the visual thinking process. Students have effectively applied the concepts
Les, Z., and Les, M. (2003). Shape understanding system: The visual reasoning process. Int. Journal of Pattern Recognition and Artificial Intelligence, Vol. 17, No. 4, pp 663-683.
learned using the tutorials in developing three dimensional solid models using AutoCAD and SolidWorks. It has been observed that the use of
Lowrie, T. (2002). The influence of visual and spatial reasoning in interpreting simulated 3D worlds. Int. Journal of Computers for Mathematical Learning, Vol. 7, No. 3, pp 301-318.
planes in the three dimensional space as well as the use of two dimensional drawing in a plane and the subsequent extruding operation to generate solid models are better understood by the students as a
Merino, D., and Abel, K. (2003). Evaluating the effectiveness of computer tutorials versus traditional lecturing in accounting topics. Journal of Engineering Education, Vol. 92, No. 2, pp 189-194.
result of the tutorials. The use of these solid modeler programs is an important tool in the design ideation process where the visualization plays a fundamental
Poli, C., Fisher, D., Pollatsek, A., and Park-Woolf, B. (2003). Design for stamping: Identifying pedagogically effective components in multimedia tutors and the classroom. Journal of Engineering Education, Vol. 92, No. 3, pp 227-237.
role as depicted in Fig. 1. V. Acknowledgement Thanks to Professor Yong Se Kim from
Zhao, H., and Kim, Y.S. (1994). Computer aided visual reasoning tool for missing view problems. American Society of Mechanical Engineers, Design Engineering Division (Publication) DE v 69-1, 20th Design Automation Conference, pp. 343-349.
Sungkyunkwan University in Korea who developed the VRT and OPT programs for allowing the author to be part of the evaluation process of these two tutorials and for the training in the use of them.
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