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Enhancing Visualization Skills in Freshman Engineering Students

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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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