Robotics Engineering CTE502

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Nov 29, 2013 (3 years and 6 months ago)

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1

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Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material and Structural Design


The History of Engineering

Revised
29 November 2013



Robotics Engineering

DoDEA
-

Career and Technical Education

Identifying Elements of Structural Design

Exercise 1


The
History of Engineering

Objective:

You will research the origin
of mechanical engineering and create a detailed timeline of ten (10)
significant accomplishments in mechanical engineering throughout history. You will also research one of many
popular engineers and inventors and describe their contributions to mechanical

engineering and the impact their
work has had on society.


Information:

Cultures and societies have flourished as the result of key inventions that have reduced our
burden, increased productivity, or enriched our lives. History is built upon the people an
d their innovations and
there have been many contributions recognized as milestones during the history of mechanical engineering.

Milestones are placed upon timelines to mark significant events. Timelines help us realize the relationship between
as well as

the sequence of these milestones. Timelines lend a greater appreciation of these accomplishments over
time. Milestones representing significant accomplishments in
e
ngineering are many. From the abacus, horse
collar, and movable type to the invention of t
he clock, automobile, and International Space Station there are many
contributions that engineers have made throughout time. Engineers such as
:




Ada Byron



Al
-
Jazari



Archimedes



Benjamin Banneker



Bonnie Dunbar



Dean Kamen



Erna Schneider Hoover



Leonardo da
Vinci



Charles Goodyear



Frederick McKinley Jones



Garrett A. Morgan



Hedy Lamarr



Hertha Ayrton



Jacques de Vaucanson



Karl Benz



Alexander Parkes



Ole Kirk Christiansen



Kenneth J. Dunkley



Lillian Gilbreth



Lonnie G. Johnson



Marie Curie



Mark Dean



Nikola Tesla



Philip Emeagwali



Robert Fulton



Leo Ba
e
kelan
d


…have all place
d

their m
ilestone

upon the timeline of innovation and service to th
is important
career
field.


Research Resources:

Web Site

Description

http://www.history
-
timelines.org.uk/


Timelines of People, Places and Events.


http://office.microsoft.com/en
-
us/templates/timeline
-
TC001016265.aspx


Templates to
produce timelines in MS Word.

http://www.black
-
inventor.com/


Famous Black Inventors

http://www.women
-
inventors.com/


Famous Women Inventors

http://en.wikipedia.org/wiki/List_of_inventors


List of inventors


Nomenclature:
Research and develop a detailed (two to three sentences) definition for each of these terms. It’s
important to realize that many

words have multiple definitions. Some of which may have nothing to do with this
course of study. Make sure your definitions fall within the context of this lesson.


Innovation

Milestone

Timeline

Mechanical Engineering

Invention

Inventor


Deliverables:

All deliverables
must
be word processed with the required student ID information in the footer of
the document.

The questions must be included in the deliverable and the answers must be highlighted.


1.

Graphic
timeline of ten significant events in engineerin
g history

from the dawn of civilization up
to

present day.

2.

Detailed
definitions for each of the terms found in the Nomenclature section

above
.

3.

An original
200 to 300 word
composition identifying
one
engineer/inventor and describing their contribution
s

and impact upon
our civilization
.
See the list of recommended individuals in Information section of this
document.


Conclusion:

Understanding how far civilization has come through the actions of innovative minds is nothing
short of remarkable. Regardless
of nationality, race, gender or socioeconomic standing the power of innovation has
brought about marvelous inventions that have contributed to the quality of life around the globe. Innovation is a skill
within all of us that must be exercised to become pr
actical. Through practice, you may become th
e

inventor
who

finds a cure for cancer, designs an engine that doesn’t pollute or solve the world’s energy crisis.

Page
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of
16

Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material and Structural Design


The History of Engineering

Revised
29 November 2013



Robotics Engineering

DoDEA
-

Career and Technical Education

Identifying Elements of Materials
and
Structural Design

Exercise 2
-

Material
s

Objective:

At the completion of this exercise, you will demonstrate your knowledge
of the properties of various
materials
, how

they are manufactured

and
then converted into the products we use
.


Information:

Closely examine the
display
that you’re reading this document from. What is it made of?
Undoubtedly, you’ll recognize
a type of
plastic, some metal and
perhaps
glass. You may also notice a bit of paint
here and there.
Although you cannot see inside the d
evice, it’s pretty clear that this

display

was manufactured from
a variety of
materials using processes that compress, stretch,
mold,
separate, fasten and coat
the
component parts

needed
to
construct

it. Of course, this would be true for any
modern
product
.
Identifying these m
aterials, their
characteristics
and application
s
, as well as how they’re processed into a useable form
s

allow us to understand how
stuff is
actually
made
.


Materials science is
a
fi
e
ld of study
that
appl
ies
the properties of matter to
the
areas of science and engineering.
Scientists that design new materials and discover
their applications

investigate the relationship
s

between the
atomic
structure
s within
materials
to better understand
their properties

and invent new materials
.


Materials fall into the following broad categories:



Biomaterials



Ceramics



Composite Materials



Metals



Polymers



Semiconductors

Mechanical properties of materials include:



Strength



Elasticity











Primary Manu

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Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material and Structural Design


The History of Engineering

Revised
29 November 2013




Plasticity



Hardness



Toughness



Fatigue


Normally
, materials are first considered for their
mechanical
(or physical)
properties
. However, some materials have
other
traits

that could benefit or

even
interfere with a product’s
manufacture or usefulness.

Electrical
properties

identify the
degree of the material’s ability to conduct or
oppose

the flow of
electricity.

Optical properties

rate the materials ability to transmit
light. Some materials are transparent while others are
translucent or opaque. Patterns in the m
aterial may also distort
or diffuse light while pigment
may be added to
change the color.

Chemical properties

determine how material
s

react with other
materials
. This includes oxidation or rusting.
Thermal properties

determine how materials
respond to form
s of energy like heat
and types of light.
Researchers, scientists and engineers must
be knowledgeable of all these
characteristics
if they are to
successfully
design
new materials
for
the
companies that make
stuff.


Primary manufacturers

process raw (natural) materials like wood, ore, minerals, natural gas and petroleum into
industrial materials also called standard stock.
The company that built
th
e

display
that
you’re studying
purchased
the standard stock like sheet metal, circuit boards
, plastic graduals and semiconductors from primary
manufactures. The display’s manufacturer
process
ed the standard stock
into the shapes
and form
s

needed to
assemble

and test
the
end product
. The process of converting industrial stock in
to

a finished produ
ct is
called
secondary manufacturing and there are six
methods

involved in this process:




Casting and Molding



Forming



Separating



Conditioning



Assembling




Finishing

The materials and manufacturing industry is incredibly vast and
provides many opportunities for
career
s
in Science,
Technology, Engineering and Math (STEM). For right now, l
et’s focus on just one
category of materials sometimes
referred to as plastics. We’
ll
determine
the origins of plastic, its
properties and
its
manufacturing processes.



Plastic is a

generic name sometimes given to a category of materials more
precisely

known as

p
olymers
. The word
“polymer” is derived from the Greek word
polumerēs
, which means
consisting of many parts or segments. The
se

segments

are
actually
replicating molecules called
monomers

(mono
means "one").

Polymerization is the process
by which
monomers
react (
combine
)

to form
long chains
that link to other polymer chains forming the ma
terial we
know as plastic. It’s these linkages and the molecular structure of the polymer that determines the material’s
properties.
Polymer
s can be
synthetic b
ut are
common in nature

as well
.

While hair, fingernails, feathers, cellulose,
proteins, rubber
and starch are all naturally occurring polymers, synthetic polymers are typically made from
chemicals refined from petroleum oil.


Partially s
ynthetic
polymers

(
like
gum elastic)

have been
around
since
1832

but i
t wasn’t until 1907 that fully synthetic polymers made the
scene.
Because plastic
from synthetic polymers
is
easier and
cheaper to
manufacture and much lighter tha
n

metal, the polymer industry has
become

larger than the
steel,
aluminum

and
copper industrie
s combined.
In fact, p
olymers

have a range of uses

that substantially surpass
that of any
other c
ategory
of materia
l
.
Ap
plications
include a
dhesives,
solvents,
coatings,
and
foams
. P
ack
aging,

textile
s,
industrial fibers, composites, electronic
devices, bio
medical devices,
and
optical devices

have also been born from
advances within this industry. Polymer research has also led to the spectacular innovations
in the emerging field of
high
-
tech ceramics
.

Considering the impact, polymers have upon
modern life, i
t’s important to understand how plastic is produced and applied in the
manufacturing process
.


“I was trying to make something
really hard, but then I thought I
should make something really soft
instead, that could be molded into
different shapes. That was how

I
came up with the first plastic. I called
it Bakelite.

Leo Baekeland

-

1907

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Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material and Structural Design


Materials

Revised
29 November 2013








A
crylonitrile (
C
3
H
3
N
)

Butadiene (
C
4
H
6
)

Styrene (
C
8
H
8
)


Let’s examine just one type of synthetic polymer in greater detail. It’s the familiar material that LEGO™ uses to
make all those
plastic
bricks, beams, plates and wheels. It’s a polymer commonly called ABS plastic which stands
for the three monomers used t
o construct the material; A
crylonitrile, Butadiene and Styrene.
ABS is a
thermoplastic and its m
olecular formula is
(
C
3
H
3
N

∙ C
4
H
6



C
8
H
8
)
n

T
hat’s a lot of carbon, hydrogen and nitrogen
atoms to

figure out how to
put together. The diagrams above may provide a clearer understanding of the molecular
structure of the monomer components and how they might fit together to form
the

small
polymer chain of ABS
plastic also shown above
.


ABS plastic

is a common
thermoplastic

used to make light
weight and
rigid products such as pip
e
, musical
instruments, automotive body parts,
helmets
, and toys
.

Thermoplastic melts to liquid when heated and
typically
harden
s

to a
strong
,
glasslike material
when
it’s
cooled
.

Polymer
s are broken down by breaking the intermolecular
bonds between them. This can be

done by

either heating
the material or introducing other monomers (like solvents)
to substitute existing reactions in the material.

The result is a reshaping or disintegration

of the polymer chains in
the polymer material.


It’s all about how the monomer
molecules
are structured and how the
y

react to produce polymer chains.
Engineers
can choose the characteristics of the materials they develop by tweaking the monomers used to build the material.
The
longer
the
polymer
chains

and increased intermolecular bonding
between the chains
… the stronger the
material becomes
.
Also, t
he

closer
the chains are
packed
together
the

more rigid the material becomes. The
polymerization
of
Acrylonitrile, Butadiene and Styrene
creates a
tough
and safe
material suitable not just for
LEGO™ but for many
consumer
products we use today.

Heated thermop
lastic can be
blow and
vacuum formed,
extruded, as well as inject
ion
, thermo
-
set, compress
ion
, insert,
and
transfer molded into a wide variety of
objects
that

serv
e

a multitude of applications.



Research Resources:

Web Site

Description

http://science.howstuffworks.com/plastic.htm


How Stuff Works

-

How Plastics Work

http://entertainment.howstuffworks.com/lego.htm


H
ow LEGO™ Bricks Work

http://www.youtube.com


YouTube
-

How do they do it? LEGO

http://www
-
materials.eng.cam.ac.uk/mpsite/default.html


Univ. Cambridge
-

Materials Selection and Processing

http://pslc.ws/


PSLC
-

Polymer Science Learning Center

http://www.pbs.org/wgbh/buildingbig/lab/index.html


PBS
-

Information
about

force
/
load upon materials
/
shapes
.

http://www.iteaconnect.org/Publications/HITSKITS/PH31D.PDF


ITEA


HITS Manufacturing Processes

http://www.materialsworldmodules.org/modules/polymers.shtml


Materials World Modules

-

Polymers Module

http://www.wolframalpha.com/


Wolfram Research
-

Computational Knowledge Engine

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16

Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material and Structural Design


Materials

Revised
29 November 2013


http://www.sciencegeek.net/eChem/eChem.html


eChem
-

3D Molecule Model Builder


Nomenclature:
Research and develop

a detailed (two to three sentences) definition for each of these terms. It’s
important to realize that many words have multiple definitions. Some of which may have nothing to do with this
course of study. Make sure your definitions fall within the context

of this lesson.



Secondary manufactur
ing



Primary manufactur
ing



Industrial Stock



Casting
/
Molding Processes



Forming Processes



Separating Processes



Conditioning Processes



Assembling Processes



Finishing Processes



Monomer



Polymerization



Composite Materials


Questions:


All deliverables
must
be word processed with the required student ID information in the footer of the
document.

The questions must be included in the deliverable and the answers must be highlighted.


1.

Partially s
ynthetic
polymers

(gum elastic)

have been ar
ound since 1832
, but there wasn’t a strong interest to
move away from natural polymers until the 2
nd

World War. Why?

2.

How would you categorize the mechanical properties of a pencil eraser?

3.

How does the choice of materials affect the
usefulness
of an object
?

4.

Using terms from the Nomenclature section of this lesson…
From nature to your book bag… Describe the
manufacturing process

and life cycle

of a pencil.

5.

From the video, “How do they do it? LEGO™”…
In 1999
,

when the video was produced our planet had 6 billion
people on it. At that time there were 62 bricks for every

man, woman and child on Earth.
Calculate the
approximate number of
LEGO™ bricks are on our planet today
.

How many towers could you build to the
Moon

with that number of bricks
?


Procedure:

Materials Lab

In this activity, you

ll
closely
examine and
then
categorize various materials according t
o

their
mechanical

properties. Each sample that you’ll evaluate is identified with a

number. Complete the

table below
rating each
material from
0

to
3

(
3

being
the
highest)
and identify
the name
and type for
each
material sample.



Required Materials and Equipment:

Volt
-
Ohm
-
Mil
l
ia
m
meter

(Multimeter)


Get
the following samples from your instructor
:


Particleboard

Wood

Plywood

Aluminum

Plastic (PVC)

Brass

Fiberglass

Steel

Glass

Ceramic

Rubber

Cotton

Cardboard

Plastic (Acrylic)

Wax


Sample

ID #

Strength

Elasticity

Plasticity

Hardness

Toughness

Fatigue

Conductivity

Opacity

Material

Name

Material Type

1











2











3











4











5











6











7











8











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Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material
and Structural Design


Materials

Revised
29 November 2013


9











10











11











12











13

1

1

2

1

1

2

0

3

Cardboard

Biomaterial

14











15












Deliverables:

Adhere to

the required format for
all
assigned work. All work must be complete to receive credit.




1.

Detailed
definitions for each of the terms found in the Nomenclature section.

2.

Detailed answers to the queries listed in the Questions section.

3.

Completed table from

the Materials Lab.


Conclusion
:

Our stuff is made from the raw materials harvested from our Earth’s natural resources. Primary manufacturers
convert these natural supplies into industrial materials or standard stock. Standard stock like sheet metal,
thread,
wood, fibers, plastic granules, and other materials are purchased by secondary manufactures where it’s casted,
molded, formed, separated, conditioned, assembled and finished into the products we purchase from stores.
Knowing the characteristics of
these materials, how they’re produced and processed helps engineers realize the
limitations of materials as they design solutions to modern engineering problems.



Page
1

of
16

Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material
and Structural Design


Materials

Revised
29 November 2013



Robotics Engineering

DoDEA
-

Career and Technical Education

Identifying Elements of Materials and
Structural Design

Exercise 2b


Making Plastic From Milk

Objective:

At the completion of this activity, you’ll demonstrate the polymerization
process using the monomer called casein that’s found in milk. You’ll create an organic
plastic and mold it into a pair of dice.


Information:

Casein plastics have been around since Leonardo da Vinci’s time. He
used the material to gesso his canvas before painting
a

masterpiece. The first plastic
buttons for clothing were made of casein, but the milk based plastic had not been
considered for
larg
e scale
manufacturing until 1897 in an attempt to manufacture
white chalkboards. The
raw materials (milk) used in the
process w
ere
expensive
compared to synthetic polymers. S
o when polymers from petroleum were
invented
,
the production of
casein plastic was

mostly
abandoned.

It

s stilled used
today
to make paper

glossy

and glues
stronger
for bookbinding.



Milk is
colloid,

or
globs of the
protein casein
suspended in water. Doesn’t that
sound yummy?

In this state, the casein is
essentially a
monomer that can

be
processed to make plastic
, but

only if the molecules could get close enough to
combine.

This process is called polymerization. Polymers are formed by
combining

(associating)
small molecules or monomers into long chains

of
molecules
. Although most plast
ics are produced from petroleum

products

and
natural gas, plastic from casein is
just one of thousands
organic polymer
s
that
exist in
nature. Since

most
of
c
ow milk is made up of
the protein
casein
under the right
conditions t
his protein can
be processed
i
nto
a natural
form of
plastic
.

Adding an acid
like
vinegar to milk causes the casein molecules to unfold
freeing the
monomers to
replicate
and produce
long chains of the polymer.
This
process
is called denaturing.
Adding heat speeds up the
reaction
and causes a more complete separation of the
casein molecular chains from the water.

Casein Formula:
(OH)C
18
H
14
N
2
O
3
C(=O)
x




Structural Diagram

3D Structure (Ball and Stick)

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of
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Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material
and Structural Design


Materials

Revised
29 November 2013


Research Resources:

Web Site

Description

http://www.youtube.com


Making Plastic From Milk Easy

http://www.sciencegeek.net/eChem/eChem.html


eChem
-

3D Molecule Model Builder

http://www.wolframalpha.com/


Wolfram Research
-

Computational Knowledge Engine


Nomenclature:
Research and develop a detailed (two to three sentences) definition for each of these terms. It’s
important to realiz
e that many words have multiple definitions. Some of which may have nothing to do with this
course of study. Make sure your definitions fall within the context of this lesson.


Gesso

Colloid

Denaturing

Casein

Acid

Associating


Questions:

All deliverables
must
be word processed with the required student ID information in the footer of the
document.

The questions must be included in the deliverable and the answers must be highlighted.


1.

What are the differences in casein content between 1%,
2% and whole milk?

2.

What other foods could be used as an acid to perform the denaturing process in this activity?

3.

What atoms are represented by the grey, white, red and blue balls in the 3D structure of the casein model?


Procedure:

Pair of Dice Lost? Pai
r of Dice Regained


Required Materials and Equipment:
This experiment can be performed at home.



9 Ounces of 2% milk



4 Tablespoons of White Vinegar



Small Mixing Bowl (Microwave Safe)



1” x 4” Cardboard Strip, 2 Each

Steps:
Complete each of the following
steps in th
is order
:

1.

Study the video, “Making Plastic from Milk

Easy” listed in the Research Resources section.

2.

Pour the milk into a microwave save bowl and heat in the microwave on high for two (2) minutes.

3.

Pour the vinegar into the heated milk and stir
until the casein finishes polymerization.

4.

Strain the casein and knead the material into a ball while mixing it into a smooth consistency.

5.

Set it aside on a paper towel to drain for about 30 minutes.

6.

Fold and tape the two cardboard strips into forms to make

two separate cubes.

7.

Allow the cubes of casein to dry for a day or two.

8.

Remove the casein
cubes
from the forms and mark them as dice.


Deliverables:

Follow the required format for
all
assigned work. All work must be complete to receive credit.






Detailed
definitions for each of the terms found in the Nomenclature section.



Detailed answers to the queries listed in the Questions section.



Completed casein dice project
.



eChem


3D molecular model of
:

a.

A
crylonitrile (
C
3
H
3
N
)

M
olecule

b.

Casein
(OH)C
18
H
14
N
2
O
3
C(=O)
x

Molecule

(Extra Credit)


Conclusion
:

Knowing what polymers are and making them yourself are two distinct learning experiences. In this activity you
applied your knowledge of polymerization and created plastic from the casein

in milk
.

You also used

a CAD
program to design a polymer molecule. In doing so, y
ou learned that monomers can be made to recombine in long
molecular chains by changing the molecules’ shape through the process of denaturing. You also learned that
thermal energy can speed up the
reaction process. It may be interesting to note that we
ingest

polymers every day.
C
heese
makers use a similar process to produce some of world’s finest cheeses. There may not be much
difference between those single slices of chees
e

you find in the grocery

store and the plastic that keeps them
separated.


Page
3

of
16

Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material
and Structural Design


Materials

Revised
29 November 2013





Robotics Engineering

DoDEA
-

Career
and

Technical Education

Identifying Elements of Materials and
Structural Design

Exercise
3



Fasteners and Fastening

Identifying Elements of Materials and
Structural Design



Objective:


At the completion of this exercise, you will demonstrate your knowledge of the
engineering/design process along with forces, materials, loads, and the structure of
bridges to design and build a model bridge that will
support a weight designated by your
teacher while utilizing the minimum amount of resources to maintain fiscal integrity.

Information:


One of the problems that engineers face today is to build a structure that is safe,
aesthetically pleasing and provides
function. Prototypes are often used in the design
process to test strength; the sh
a
pe of the structure is the most important feature for supporting its load.

Nomenclature:

Vocabulary Words



Load

Force

Resistance

Tension

Compression

Shear

Architectur
al structure

Civil structure

Steel

Reinforced steel

Reliability



Research Resources:

Institution

Web Site

Description

PBS

http://www.pbs.org/wgbh/buildingbig/

Information regarding building various
structures on large and small scales.



US Military
Academy at
West Point

http://bridgecontest.usma.edu/index.htm

Provides virtual software for bridge
building as well as a physical bridge
model for

construction using simple
materials.



http://architecture.about.com/od/greatbuildings/Great_
Buildings_and_Structures.htm

Excellent source of information f
or a
wide variety of architectural structures.


Institute of
Structural
Engineers

http://www.istructe.org/Pages/default.aspx

Provides information on a career in
structural engineering.


Questions
:

4.

Research and develop a detailed definition for each of the terms found in the Nomenclature section of this
document. Many words have multiple definitions. Some of which may have nothing to do with the field of
Robotics Engineering. Make sure your definit
ion falls within the context of this lesson.

5.

Analyze the changes in structures from the ancient Egyptians to today. What differences and similarities do
you see between then and now?

6.

What shapes provide more support for load bearing structures? Why?


Page
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of
16

Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material
and Structural Design


Materials

Revised
29 November 2013


7.

Diff
erentiate between tension and compression and explain how these forces are balanced on a bridge.

8.

How does the choice of materials affect the structure? Give examples throughout history.

9.

Why are trusses frequently used in the construction of bridges and skyscrapers?

10.

What are the advantages and disadvantages of the truss design?

Procedure:

Exercise Instructions


Required Materials and Equipment:
Get these materials and tools from your in
structor.

File folders

Cardboard base

Wood glue

Pins

Ruler

Scissors

Wax paper




Steps:
Complete each of the following steps in the assigned order:

1.

Use the Engineering/Design worksheet to design a model bridge that will support a designated load.

2.

Document each stage of the process fully.

3.

Build your model.

4.

Perform mathematical computations to predict load bearing ability.

5.

Weigh your model.

6.

Test your structure by adding weights incrementally. If time allows, refine and retest.

7.

Perform destructive te
sting for maximum efficiency.

8.

Report results.


Conclusion
:

In completing this exercise you will be able to recognize the importance of triangles related to structural
engineering. You will see that triangles are the basic geometry involved in building structures like bridges. A truss
is a structure made of one o
r more triangles built using straight members connected by joints. Tension and
compression are forces that act on a truss. The forces of tension and compression must be balanced for a bridge
to be stable. Different situations require different materials

based on their properties. When using members to
build a truss, it is important to identify whether the member will be subject to more tension or compression as to
what type to use. Hollow members have different characteristics than solid and steel acts

differently than carbon
-
steel and the thickness makes a difference in terms of support but also adding load to the structure. Combining the
right elements to produce a safe, reliable structure within the budgetary requirements is not an easy task.



Page
5

of
16

Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material
and Structural Design


Materials

Revised
29 November 2013




Robotics Engineering

DoDEA
-

Career
and

Technical Education

Identifying Elements of Structural Design

Exercise 4


Truss

Design

Identifying Elements of Materials and Structural Design


Objective:


At the completion of this exercise, you will demonstrate your knowledge of the
truss design and necessary components to support a load.

Information:


One of the problems that engineers face today is to build a structure that is safe,
aesthetically pleasin
g and provides function. Prototypes are often used in the
design process to test strength; the shape of the structure is the most important
feature for supporting its load.

Nomenclature:

Vocabulary Words



Load

Force

Resistance

Tension

Compression

Shear

Architectural structure

Civil structure

Steel

Reinforced steel

Reliability





Research Resources:

Institution

Web Site

Description

PBS

http://www.pbs.org/wgbh/buildingbig/

Information regarding building various
structures on large and small scales.



US Military Academy at
West Point

http://bridgecontest.usma.edu/index.htm

Provides virtual software for bridge
building

as well as a physical bridge
model for construction using simple
materials.



http://architecture.about.com/od/greatbuildings/
Great_Buildings_and_Structure
s.htm

Excellent source of information for a
wide variety of architectural structures.


Institute of Structural
Engineers

http://www.istructe.org/Pages/default.aspx

Provides information on a career

in
structural engineering.





Questions:

11.

Research and develop a detailed definition for each of the terms found in the Nomenclature section of this
document. Many words have multiple definitions. Some of which may have nothing to do with the field of
Robotics Engineering. Make sure your definition falls within the context of this lesson.

12.

Analyze the changes in structures from the ancient Egyptians to today. What differences and similarities do
you see between then and now?

13.

What shapes provide more
support for load bearing structures? Why?

14.

Differentiate between tension and compression and explain how these forces are balanced on a bridge.

15.

How does the choice of materials affect the structure? Give examples throughout history.

16.

Why are trusses freque
ntly used in the construction of bridges and skyscrapers?

17.

What are the advantages and disadvantages of the truss design?



Page
6

of
16

Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material
and Structural Design


Materials

Revised
29 November 2013


Procedure:

Exercise Instructions


Required Materials and Equipment:
Get these materials and tools from your instructor.

Lego Mindst
orms NXT kit

Weights

Platform to support weights
(optional)







Steps:
Complete each of the following steps in the assigned order:


9.

Collect materials.

10.

Create a truss design without the internal members to span a distance identified by your teacher
(30
-
60
cm suggested)

11.

Predict how much weight will be supported by this truss.

12.

Put the platform on the truss and begin to slowly add weights. Document how much weight it can hold
(for more than 3 seconds) before the structure fails. How did your predictio
n match the results?

13.

Reassemble the truss structure utilizing the internal members and the triangular reinforcements.

14.

Predict how much weight will be supported with this truss.

15.

Repeat the test with the weights. Document your results.

16.

Discuss the reasons f
or the differences observed.


Conclusion
:


In completing this exercise you will be able to recognize the importance of triangles related to structural
engineering. You will see that triangles are the basic geometry involved in building structures like br
idges. A truss
is a structure made of one or more triangles built using straight members connected by joints. Tension and
compression are forces that act on a truss. The forces of tension and compression must be balanced for a bridge
to be stable. Diff
erent situations require different materials based on their properties. When using members to
build a truss, it is important to identify whether the member will be subject to more tension or compression as to
what type to use. Hollow members have differe
nt characteristics than solid and high strength/low alloy steel acts
differently than carbon
-
steel or quenched and tempered steel. The thickness makes a difference in terms of
support but also adds load to the structure. Combining the right elements to p
roduce a safe, reliable structure
within the budgetary requirements is not an easy task.



Page
7

of
16

Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material
and Structural Design


Materials

Revised
29 November 2013




Robotics Engineering

DoDEA
-

Career and Technical Education

Identifying Elements of Structural Design

Exercise
5



Designing and Analyzing Virtual Structures

The
goal of the West Point Bridge Designer Challenge is
to design
a structurally sound bridge that costs the
least amount of money

to construct
. Before you start
this competition, each team must login to a computer
workstation and create a folder for your

team
named

“C:
\
Temp
\
WPB
D
”. Next, launch the West Point Bridge
Design Software. Each team must also maintain a
design log. This will be your
deliverable and evidence of
completion of this task
. As you complete each new
successful bridge ask for
the instru
ctor
to validate the
load test and initial next to the new bridge name on your
design log. Save each bridge with a unique file name
into your folder in
to

the “C:
\
T
emp
\
WPB
D
” folder. Files
should be named bridge1, bridge2, and bridge3 in order
as each new su
ccessful bridge is saved. Again… Your
bridges will be saved to the C:
\
T
emp
\
WPB
D

folder.


1.

Fill out the top of the “Design Log” with your name(s) and team name.

2.

Start the West Point Bridge Designer software

3.

Select “Create New Bridge Design” and use the desig
n Wizard.

1

Read only

2

No

3

Deck Elevation = 20 meters; standard abutments; no pier;
no

cable anchors

4

Medium strength; standard

5

Suspension

6

Enter team name; designer: team member initials (ex. jk/rb)

7

Read, then select finish

4.

Begin designing!

5.

Save
each design to the proper folder with the proper name.

6.

Have a monitor initial each successful design.


Good luck! You have
60

minutes.










Page
8

of
16

Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material
and Structural Design


Materials

Revised
29 November 2013


WEST POINT BRIDGE DESIGN
ER

COMPETITION

Design Log

Judge’s Official Rating Sheet

















Team:



Final Ranking:


Entrant Init
:

# 1

#2



Bridge

New Cost

Monitor’s Initials

Brid来

乥w⁃潳t

Monitor’s Initials

1.



26.



2.



27.



3.



28.



4.



29.



5.



30.



6.



31.



7.



32.



8.



33.



9.



34.



10.



35.



11.



36.



12.



37.



13.



38.



14.



39.



15.



40.



16.



41.



17.



42.



18.



43.



19.



44.



20.



45.



21.



46.



22.



47.



23.



48.



24.



49.



25.



50.




I certify these results to be true and accurate to the best of my knowledge and

ability.























Judge’s Name (Print)

Judge’s Signature




Page
9

of
16

Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material
and Structural Design


Materials

Revised
29 November 2013





Robotics Engineering

DoDEA
-

Career & Technical Education

Identifying Elements of Materials and
Structural Design

Exercise 2a


Utilizing Engineering Design Process to
Build a Support Structure

Identifying Elements of Structural Design


Objective:


At the completion of this exercise, you will demonstrate your knowledge of the
shape that will support the most weight.

Information:


One of the problems that engineers face today is to build a structure that is
safe, aesthetically pleasing and provides function. Prototypes are often used
in the design process to test strength; the shape of the structure is the most
important feature fo
r supporting its load.

Nomenclature:

Vocabulary Words



Load

Force

Resistance

Tension

Compression

Shear

Architectural structure

Civil structure

Steel

Reinforced steel

Reliability





Research Resources:

Institution

Web Site

Description

PBS

http://www.pbs.org/wgbh/buildingbig/

Information regarding building various
structures on large and small scales.



US Military Academy at
West Point

http://bridgecontest.usma.edu/index.htm

Provides virtual software for bridge
building as well as a physical bridge
model for construction using simple
materials.


http://architecture.about.com/od/greatbuildings/
Great_Buildings_and_Structures.htm

Excellent source of information for a
wide variety of architectural structures.


Institute of Structural
Engineers

http://www.istructe.org/Pages/default.aspx

Provides information on a career in
structural engineering.





Questions:

18.

Research and develop a detailed definition for each of the terms found in the Nomenclature section of this
document. Many
words have multiple definitions. Some of which may have nothing to do with the field of
Robotics Engineering. Make sure your definition falls within the context of this lesson.

19.

Analyze the changes in structures from the ancient Egyptians to today. What di
fferences and similarities do
you see between then and now?

20.

What shapes provide more support for load bearing structures? Why?

21.

Differentiate between tension and compression and explain how these forces are balanced on a bridge.

22.

How does the choice of mate
rials affect the structure? Give examples throughout history.


Page
10

of
16

Robotics Engineering


DoDEA Career and Technical Education

Identifying Elements of Material
and Structural Design


Materials

Revised
29 November 2013


23.

Why are trusses frequently used in the construction of bridges and skyscrapers?

24.

What are the advantages and disadvantages of the truss design?




Procedure:

Exercise Instructions


Required Materials and Equipment:
Get these materials and tools from your instructor.

File folder

Scissors

Masking Tape




Steps:
Complete each of the following steps in the assigned order:


17.

Collect materials.

18.

Document the entire process using the engine
ering/design process handout.

19.

Use materials to create a structure that will support a weight provided by your teacher. This may be a
series of textbooks, a brick or some other weight.

20.

Test your structure, modify as necessary and re
-
test.

21.

Record your obser
vations.

22.

Clean up.


Conclusion
:

In completing this exercise you will be able to recognize the importance of the engineering design process in all
aspects of engineering. In this exercise you saw that columns play an important role in structural engineering.
Columns are used in many str
uctures to support great weights in the form of floors and roofs. Choosing the correct
materials and deciding the height and diameter of the column is not an easy task. Many factors must be taken into
account when constructing a safe, reliable structure
within the budgetary requirements. Documentation is the key
to ensuring that mistakes are learned from and successes are repeated.