DESIGN PROJECT #1
Cardboard Furniture Design
Introduction to Engineering Design
EDGSN 100 Section 003
Team No Show
Team 6
Taylor Hoover, http://www.personal.psu.edu/tjh5287,tjh5287@psu.edu
Jordan Barner, http://www.personal.psu.edu/jdb5450, jdb5450@psu.edu
Dong-ho Kim, http://www.personal.psu.edu/duk20, duk20@psu.edu
Sean Herrmann, http://www.personal.psu.edu/smh5649, smh5649@psu.edu
Submitted to: Prof. Berezniak
Date: 2/23/10
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Spring 2011
PROJECT TITLE
Table of Contents
1.0
2.0
3.0
4.0
Introduction………………………………………………………………………………………. Page 4
Mission Statement…………………………………………………………………………….. Page 4
Customer Needs Analysis……………………………………….…………………………..Page 4
External Research………………………………………….…………………………………… Page 5
4.1 Library/online………………………………………….…………………….……….. Page 5
4.2 Patent research………………………………………………………………………. Page 6
4.2 Benchmarking…………………………………….…………………………………… Page 6
5.0 Target Specification……………….……………….……….………………………………… Page 7
6.0 Concept Generation………………………..…………….……………………………………Page 8
6.1 Structural Integrity…………………………………………………………………. Page 10
7.0 Concept Selection……………………………………………………………………………… Page 11
8.0 Final Specification……………………………………………………………………….…….. Page 13
8.1 Cost Analysis………………………………………………………………………….. Page 14
9.0 Final Design……………………………………………………………………………………….. Page 15
9.1 The Model……………………………………………………………………………… Page 17
10.0 Conclusions……………………………………………………………………………………… Page 18
11.0 References………………………………………………………………………………………. Page 19
List of Tables
Table #1
Table #2
Table #3
Table #4
Table # 5
Table # 6
Table # 7
Table # 8
Customer Importance Table …………………………….……..…..…… Page 5
Competitive Products………………………………………………………… Page 6
Benchmarking of Four Products……………………………………..…. Page 7
Target Specifications……………………………………………….……..…. Page 8
Concept Screening Matrix…………………………………………………. Page 11
Concept Selection Matrix………………………………………………….. Page 12
Final Specifications……………………………………………………………. Page 13
Cost Analysis of Cardboard Chair………………………………………. Page 14
List of Figures
Figure #1
Figure #2
Figure #3
Figure #4
Figure #5
Figure #6
Figure #7
Figure #8
Figure #9
Figure #10
IKEA Chair SKRUVSTA…………………………………………….………..… Page 8
Concept 1….………………………………………………………….………..… Page 9
Concept 2….………………………………………………………….………..… Page 9
Concept 3…………………………………………………………………………. Page 9
Structural Integrity……………………………………………………………. Page 10
Selected Concept………………………………………………………………. Page 12
Cost Analysis of Cardboard Chair………………………………………..Page 14
The Seat Base is Now Square in Nature…………………………….. Page 15
Concept Stands Taller……………………………………………………….. Page 15
Circular Columns…………………………………………………….…………. Page 15
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Spring 2011
Figure #11
Figure #12
Figure #13
Figure #14
Figure #15
Figure #16
Figure #17
Right, Top, and Front Views of the Seat Portion………………… Page 16
Front and Top Views of the Support Column………….…………. Page 16
Top and Front Views of the Chair Base……………………………… Page 16
Final Concept………………………………………………………….…………. Page 17
Prototype………………………………………………………………………….. Page 17
Prototype Follows Model……………………………………….…………. Page 17
Prototype Disassembles into 3 Parts…………………………………. Page 17
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Spring 2011
Abstract (Executive Summary)
Team No Show task was to design a cardboard chair. The only restrictions of this product, is
that it needs to be able to hold a minimum 80lbs load and fit under a 12-inch space. We
narrowed a target consumer, specifically college students living in dorms. From there our
research led to important features such as cup holders, swivel ability, and contemporary
design. Subsequently, sketches and models were made of our chair. Also testing was done on
cardboard structural components to optimize the strength of the chair. Finally the building
process commenced and we built a half scale model of our chair.
1.0 Introduction
The goal set forth by our engineering design teacher was to come up with a functional
cardboard. It chair took many hours of work in and out side the lab to complete this task. The
first step we took was to getting ideas for the chair and finding out the customer wants.
Various research methods were conducted such as browsing furniture stores and giving
personal surveys. From this, we were able to develop a customer need analysis, which allowed
us select and prioritize our features. From there a concept was designed and scale models
were built. This allowed us to express everyone ones ideas. From there, the ideas were
integrated into a final design, in which it was built. From the build, a cost analysis was
calculated and completed. From all these steps and process, Team No Show was able to
engineer a cardboard chair.
2.0 Mission Statement
Our mission is to design and build a cardboard chair. The chair itself needs to have an
appealing design, functional in a college dorm, affordable for the average student, and meet
certain requirements of fitting under a 12-inch space and holding the minimum 80 lbs load.
3.0 Customer Needs Analysis
In process of gather information about customer needs, several approaches were taken. The
first approach was to look at current furniture and get ideas and concepts from them. We
mostly looked through the IKEA Website until we discovered a chair that we were going to base
ours from. Afterward, we all broke up and individually conducted research through a survey.
We then asked our target consumer of what they wanted to see in a cardboard chair. From
there, a customer importance table was constructed and listed all of the needs and rated them
on a 1-5 scale
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Spring 2011
Table #1
Customer Importance Table
No.
Need
Imp.
1
Cardboard Chair
is light weight
3
2
Cardboard Chair
last a long time
3
3
Cardboard Chair
can be easily and quickly
assembled
4
4
Cardboard Chair
meets design requirements
5
5
Cardboard Chair
ability to swivel around
3
6
Cardboard Chair
has appealing design
4
7
Cardboard Chair
fits into a college dorm setting
4
8
Cardboard Chair
is safe for all users
5
9
Cardboard Chair
is affordable for students
3
10
Cardboard Chair
has many extra commodities
2
4.0 External Research
Research is very important in engineering design. If you don’t what is out there, then how can
you expect to make improvements? For that reason we researched the history of cardboard
furniture, cardboard furniture patents, and current chair designs on the market.
4.1 Literature Search
Not knowing much about cardboard furniture, our group decided to search the Internet for
ideas and information about the topic. After some searching, we realized that cardboard
furniture wasn’t as much of an oddity as we thought. In fact, there are many Internet sites out
there that sell either constructed cardboard furniture or blueprints for cardboard furniture.
Through our research we began to realize that cardboard furniture is very practical, and not just
because of the fact that it is cheap. Cardboard furniture is better for the environment,
incredibly easy to ship and move, easy to maintain and repair, and, among other things, highly
customizable.
After figuring out why cardboard furniture is so practical, our next step was to see what type of
design was practical. To do this, we went to IKEA’s website and looked at there designs. This
gave us an idea as to what is important in furniture and also as to what type of furniture is in.
Their website also sparked our imaginations and led us to create our own conepts.
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Spring 2011
4.2 Patent Search
In every design project it is important not to infringe on someone else’s patents. Patent
infringement can leave one liable to pay an abundance of legal fees and fines. Our group
decided it was important to search for cardboard furniture patents on the Internet. We were
only able to find one patent pertaining to cardboard furniture. This was U.S. patent 4,934,756
that patents the use of interlocking cardboard pieces to create a more rigid structure.
4.3 Benchmarking
During our research on cardboard furniture, we came across products that are cardboard chair
would compete against. Out of all of these products, we narrowed the list down to three.
These were products that we felt like we would compete against most. Table 2 shows these
products.
Table #2
Competitive Products
Competitive Product A
Competitive Product B
Competitive Product C
These products were then benchmarked against one of our concepts (we chose concept 2),
using selection criteria that we felt were important in cardboard chairs. Each of these selection
criteria was weighted as to put more importance on some more than others.
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Spring 2011
Table #3
Benchmarking of Four Products
Ease of Use
Aesthetics
Weight
%
25%
10%
5
4
Concept 2 (from Section 6.0)
Ranking
Weighted Score
1.25
.4
Swivels
10%
5
.5
Durable
15%
3
.45
Ergonomics
Cost
Structural Integrity
Extra Features
10%
5%
20%
5%
3
4
2
1
.3
.2
.4
.05
Selection Criteria
Ease of Use
Aesthetics
Weight
%
25%
10%
5
2
Competitive Product B
Ranking
Weighted Score
1.25
.2
Swivels
10%
0
0
Durable
15%
3
.45
Ergonomics
Cost
Structural Integrity
Extra Features
10%
5%
20%
5%
Total Score
Rank
1
4
2
1
.1
.2
.4
.05
Selection Criteria
Total Score
Rank
2.65
4
3.55
2
Competitive Product A
Ranking
Weighted Score
5
5
0
4
4
2
4
1
1,25
.5
0
.6
.4
.1
.8
.05
Competitive Product C
Ranking
Weighted Score
5
4
0
3
3
3
2
1
1.25
.4
0
.45
.3
.15
.4
.05
3.00
3
3.70
1
The benchmarking process saw our concept lose out to Competitive Product A. This meant that
our product would have to improve before it hit the market. Our product lacked in structural
integrity and extra features. The structure in our concept just did not look as if it could both
hold and balance the weight it needed to. Our design also lacked extra features that set it apart
from the rest of the chairs. An extra feature, such as a cup holder, needed to be added to
differentiate our chair from the rest of the pack.
5.0 Target Specification
The target specifications for our chair were set after gaining customer feedback and opinions
about what is important to consumers in furniture. The group members compiled all of the
data obtained from the surveys and ranked the customer needs in order of importance. From
there a list of metrics for the chair were developed that aimed to meet most, if not all, of the
customer needs.
These metrics give the target specifications along with our current
specification value, the ideal value (what is most wanted) and the marginal value (what is at the
bare minimum acceptable). Our specifications were kept in mind as we developed concepts.
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Spring 2011
Table #4
Target Specifications
Feature
Capacity
Height
Width
Depth
Ease of use
Swivels
Fits under bed
Target Specs
Ideal
Marginal
250 pounds
80 pounds
32 inches
28 inches
22 inches
18 inches
22 inches
18 inches
Constructed in less
Constructed in less
than 30 seconds
than 2 minutes
360 degree motion
180 degrees
L, W, or H is less than L, W, or H is 12 inches
or equal to 12 inches
Current Specs
TBD after testing
32 inches
24 inches
22 inches
Constructed in 10
seconds
360 degree motion
Length, width, or
height is 12 inches
6.0 Concept Generation
Concepts generated should be explained through a combination of sketches and accompanying
text. All sketches should be should in digital format (if drawn manually please add scanned
sketches in your report.) Use the Morphological chart (concept combination table), example
provided below, to organize as many concepts as your team can generate. More is better and
will be rewarded.
Our first step in coming up with a concept for the chair was browsing the Internet. Eventually
one design caught the groups’ eyes as something that could work. On the IKEA site we found a
chair named SKRUVSTA, see figure 1, that
seemed to fit most of our customers’ needs and
wants.
This chair featured many of the characteristics
of chairs that our target consumers desired.
Our consumers were looking for something
stylish and comfortable that would be
appropriate for a dorm room setting. This chair
swiveled making it even more practical busy
body college student. The design also looked
as if it could easily be disassembled into three
different pieces making for simplistic assembly.
For these reasons, we chose to use this chair as
inspirations for original concepts.
Figure 1: IKEA Chair “SKRUVSTA”
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Spring 2011
From there, our team created three concepts that incorporated elements of the IKEA chair as
well as the needs and wants of the customers.
Concept 1, figure 2, featured the same circular base and
curved back that the IKEA chair sported. The concept
deviated from the inspiration, with its use of four circular
column legs. These legs could easily be detached making
for easy assembly, disassembly, and storage under a college
student’s bed. The concept also featured a weaved back
that promised to add stability and durability to the chair.
The group’s second concept, figure 3, play direct homage to
the IKEA chair, featuring almost all of the design elements
that its inspirer had. Concept 2 featured a near circular seat
with a curved back. A single circular column supported the
chair. This circular column allowed the chair a full 360
Figure 2: Concept 1
degree range of motion. The single support column,
however, raised questions as to whether the chair would be
strong enough to support the load and would also be able
to successfully balance the weight of its load. This concept
could be disassembled into three parts that allowed for easy
under the bed storage. Oppositely, the chair could be
assembled within mere seconds. As the chair was closely
based off of the IKEA model, the aesthetics of the chair
were top notch and appropriate for a dorm room setting.
Concept 3, figure 4, did not deviate much from the other
two concepts. It instead tried to improve the strength of the structure of the chair. In order to
support the base, the Figure 3: Concept 2
chair used an x
frame. This intended to provide support for the entire
seat base. The design, like the others, is aesthetically
pleasing as it employs a rounded back and circular style
seat. Unlike concept 2, however, the chair is completely
stationary and cannot move.
Figure 4: Concept 3
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Spring 2011
6.1 Structural Integrity
With three different concepts envisioned, it was now important to determine the structural
integrity of the various cardboard elements that could potentially be used in our cardboard
chair design.
This was done
by building Lshaped,
circular, and
square
structural
elements.
Each element
shape was
built at the
dimensions of
2 x 8, 2 x 16,
and 2 x 24,
and tested
twice. A load
was applied
via a lever
until breaking
point. The
data was then
compiled and
analyzed. A
safety factor
was added to
the chart to
Figure 5: Structural Integrity
ensure that
the structural
elements were safe. Figure 5 shows a summary of the data.
From this summary we were able to concur that squares are the strongest structural element,
followed by L-shapes, and then circles. The lack of structural integrity of the circular structural
elements is due to the cardboard being bent in numerous places in order to make a circle. The
L shapes held up well as they featured only one bend. The squares, basically two L’s put
together, held up decisively better than the other 8 and 16 inch elements. For this reason, it
was decided upon that square supports would be featured in our design. Although all the
structural held close to, if not more than, 80 pounds, the use of squares assured us that we
would not have to worry about the structural integrity of our chair.
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Spring 2011
7.0 Concept Selection
The concept development phased saw the creation of the three different concepts. Now our
group was tasked with the difficulty of narrowing the designs down to one. To do this our
group used a concept screening matrix. This matrix allowed for a direct comparison between
the designs and our inspiration using selection criteria we felt were important to have in our
chair.
The criteria we used as our selection criteria were what we felt were most important in creating
a marketable chair. These were ease of use (chair will fit under the bed), aesthetics (chair looks
nice and suits a dorm room environment), the ability to swivel (chair has a full 360 degree range
of motion), durability (chair will last and endure the rigors of a college dorm room), ergonomics
(chair should be comfortable to sit in for long periods of time), cost (chair should be a
reasonable price), structural integrity (chair should be able to hold the loads put on it), and
extra features (chair should have something that sets it apart). These criteria were used in an
effort to narrow our chair concepts down. Table 5 shows how we did this.
Table #5
Concept Screening Matrix
Concepts
Selection
Criteria
1
2
3
IKEA Chair
(Reference)
Ease of use
Aesthetics
Swivels
Durable
Ergonomics
Cost
Structural
Integrity
Extra features
0
0
0
0
0
0
+
0
0
0
+
-
0
0
0
+
0
0
0
0
0
0
0
0
0
0
0
0
0
4
3
-2
4
No
2
5
1
1
1
Yes
1
5
2
-1
3
No
0
8
0
0
2
Combine
Sum +’s
Sum 0’s
Sum –‘s
Net Score
Rank
Continue?
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Spring 2011
As it turned out, concept 1 was eliminated from contention, losing out to concepts 2 and 3 and
also our inspiration/reference chair (IKEA Chair).
Still left with two different concepts, we decided to use a concept selection matrix. This
allowed us to weigh the selection criteria in an effort to decide which chair was better at what
it did overall. Table 6 shows our results.
Table #6
Concept Selection Matrix
Selection
Criteria
Wt
%
Ease of Use
Aesthetics
Swivels
Durable
Ergonomics
Cost
Structural
Integrity
Extra Features
25%
10%
10%
15%
10%
5%
20%
3
4
5
3
3
1
5
5%
1
IKEA Chair (Reference)
Ranking
Weighted
Score
.75
.4
.5
.45
.3
.1
1.0
.05
Ranking
5
4
5
3
3
4
2
1
Concept 2
Weighted
Score
1.25
.4
.5
.45
.3
.2
.4
.05
Concept 3
Ranking
Wt’ed
Score
4
4
1
3
3
4
4
1.0
.4
.1
.45
.3
.2
.8
1
.05
Total Score
Rank
3.45
2
3.55
1
3.30
3
Continue?
No
Develop
No
The concept selection matrix effectively narrowed down our number of concepts to one.
Concept 2 was the winner of the selection matrix and the design that we decided to proceed to
make. Figure 6 shows our selected concept.
Figure 6: Selected Concept
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Spring 2011
8.0 Final Specification
With our concept chosen, it was now time to establish our final specifications, or the final
features and design aspects of our chair. The final specifications did not change much from the
target ones as all of the features remained intact with only two being refined and one added.
The design our team chose allowed us to further refine the ease of use metric. Previously we
had stated that our chair could be constructed in 10 seconds, but now we felt confident that
the chair’s design allowed it be assembled in as little 5 seconds. For marketing purposes, we
made the specification state that the chair could be constructed in less than 10 seconds. After
taking a look at our original consumer needs surveys, we felt that it was important to add some
extra features that set the chair apart. A few of our target consumers had stated that they
would like to see cup holders. We realized that this design feature was incredibly easy to
implement and wouldn’t significantly add to the labor or materials cost. For that reason, we
decided to add 2 cup holders to our final specification list. The addition of cup holders got our
team thinking yet again, and we decided to raise our chair height 6 inches. These 6 inches gave
the chair a taller, more slender appearance, allowing for our team to market the chair as both a
normal chair and also as a bar stool, perfect for the college student demographic.
Table #7
Final Specifications
Feature
Capacity
Height
Width
Depth
Ease of use
Swivels
Fits under bed
Cup holder
Current Specs
TBD after testing
32 inches
24 inches
22 inches
Constructed in 10
seconds
360 degree motion
Length, width, or
height is 12 inches
0 cup holders
13
New Specs
TBD after testing
38 inches
24 inches
22 inches
Constructed in less
than 10 seconds
360 degree motion
Length, width, or
height is 12 inches
2 cup holders
Spring 2011
8.1 Cost Analysis
Figure 7: Cost Analysis of Cardboard Chair
Cost Analysis of Cardboard Chair
300.0
253
250.0
162
200.0
169
150.0
100.0
50.0
3.9
2.8
0.0
1
2
3
4
5
Table #8
Cost Analysis of Cardboard Chair
Components of Chair
Amount Used
Cost per unit
Cost ($)
Base
6.63 sq. ft.
$0.1/ sq. ft.
0.663
Center Post
19.2 sq. ft.
$0.1/ sq. ft.
1.92
13.62 sq. ft.
$0.1/ sq. ft.
1.362
Seat
Total Cost Of Card Board: 1
3.9
Estimated Cost of Hot Glue: 2
1 lbs
$2.76/lb
2.8
Overhead and Employee Costs: 4
10 hr
$16.20/hr
162
Total Cost of Production: 5
Final Selling Price: 6
169
Total Cost x
1.5
14
253
Spring 2011
The results show an extremely steep production cost for the full-scale chair, $169. This
occurred because the chair was a prototype. The design process took enormous amounts of
time and energy to complete the chair. In Cost Analysis Figure, the highest costs were
overhead and employee costs. Furthermore the materials cost for the chair were relatively low,
approximately $6.7. A solution to the high production cost is improving the production process.
Using machines to cut and assemble cardboard on a large scale or finding cheaper employees
and facilities can achieve lower production costs. With dramatically lower production cost, a
target price for the chair would be close about $30 instead of the $253 price tag.
9.0 Final Design
With the final specifications in hand, our team chose to use Solid Works to design and visualize
our final design concept, from which our prototype chair would be built. After a short time, our
team finally came up with our final design. The design was closely based on concept 2,
incorporating the basic shape and structure of that design. Alterations were made to the
design after realizing the limitations of cardboard.
The seat base was now square in nature with its corners
cut off. The front of the seat featured the only curved
lines in an attempt to contour the chair to our
consumers’ bodies. Figure 8 shows a top view of our
design, which illustrates our seat base.
As we decided upon in our final specifications, our final
design was taller than our original
Figure 8: The seat base is square in nature
concept. This was in an effort to make
the chair more marketable to college students. The final design looks more like a
bar stool and thus make influence some of our college student demographic.
Figure 9 shows the tall, slender that our final design sported.
Throughout our design process, we felt that it was important for our chair to
swivel. When we saw the load testing results of the circular columns we became
a little discouraged. The use of circles was the only way that we were going to
be able to our chair rotate. Eventually, we realized that we could simply
use a square support beam to support our chair and wrap a circular
support beam around it. This allowed for strong stability as well as
allowing us to incorporate the design feature we use so desired.
Figure 10 shows how we wrapped a circular column around the square
support column and how the chair fits together. Circular columns were
attached to both the chair base and the bottom of the seat, which allowed
the circular/square hybrid support column to attach to both pieces. This
Circular
allowed for an easy two step assembly process.
The last design element that was added was the addition of the cup
Figure 9:
Concept stands
taller
Figure 10:
columns
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Spring 2011
holders. One cup holder was added to either side of the chair’s arms. The implementation of
two cup holders ensure that the chair would keep a symmetrical look and remain aesthetically
pleasing.
Our chair was created through the use of three components: the seat, the support column, and
the chair base. The seat features a double cardboard ply square in nature base with a back
going around it. The chair sides are angled to improve comfort. On each side a cup holder was
added. A circular column was added to bottom of the seat to connect the seat to the support
column and to also facilitate in swivelling and rotating.
Figure 11: Right, Top, and Front views of the seat portion of the chair
The support column features a
square support encased in a
circular column wrapping. This
allows for stronger stability
than what a circular column
would have brought to the
table, without sacrificing the
ability to rotate.
Figure 12: Front and Top views of the support column
The chair base is what balances
the chair. It is made out of
double ply circular cardboard.
Added to this was a circular
column placed in the middle,
so that the base could attach
to the support column. This
also allows the chair to swivel.
Figure 13: Top and Front views of the chair base
After we decided upon the final design, we built the chair. The chair took us two classes to
build and closely resembles our design model.
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Spring 2011
9.1 The Model
Versus
Figure 14: Final concept
Figure 15: Prototype
The prototype chair has every design
feature that our model concept did. We
were successfully able to implement every
feature, including manipulating the
cardboard enough to be able to make the
chair rotate.
In our prototype chair, we were able to
successfully implement the “Less than 10
second assembly”. The chair disassembles
into three parts for easy storage and is
able to be put back together with relative
ease.
Figure 17: Prototype disassembles into 3 parts
Figure 16: Prototype follows model
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Spring 2011
10.0 Conclusions
We feel that our project was extremely successful. We were able to design a low cost
useful piece of furniture that fits in a dorm room easily. While the cost of the prototype may
have been high, we feel that once the model goes into production, that cost will fall
dramatically. The chair is assembled from three different parts making it easy to store in small
areas when not in use. The assembly is extremely easy taking less than 10 seconds to fully
assemble. It can also support a weight of over 80 pounds. We wanted to make our product
stand out from other chairs so we decided to add a few extra features. The chair can rotate
360 degrees making it more versatile than other chairs like it. It also features two cup holders
so that a student can keep a drink close when studying for that big exam. Overall, our product
meets the criteria presented to us with a few added extras to make it more appealing.
The cup holders allow for
students to study with a drink
close by.
The seat is ergonomically
shaped, designed to fit the
contours of the body
The chair
disassembles into 3
parts making for easy
storage
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Spring 2011
11.0 References
A sample reference list addressing each of the five main types of information sources is given
below. These include: websites (Swanson, 1999, and NASA, 2004), journals (Muriru and
Daewoo, 2002), books (Zacharia and Daudi, 2001), conference proceedings (Peters et al., 2001)
and patents (Wen-Cheng, 1994). Add all references in this section.
Note: That for the author-date system, references are listed in alphabetical order.
Budweiser. Photograph. Innovative Cardboard.com. 2011. Web. 7 Feb. 2011. <http://www.innovativecard
board.com/>.
"Cardboard Furniture." Patent Searching and Inventing Resources. 2011. Web. 3 Feb. 2011. <http://www.free
patentsonline.com/4934756.pdf>.
"IKEA | Fabric Sofas | Fabric Armchairs | SKRUVSTA | Swivel Chair." Welcome to IKEA.com. 2011. Web. 2 Feb.
2011. <http://www.ikea.com/us/en/catalog/products/10074590>.
Photograph. Radio National EarthBeat. 17 July 1999. Web. 7 Feb. 2011. <http://www.abc.net.au/rn/science/
earth/stories/s36786.htm>.
Photograph. Watkins Memorial High School Engineering Foundations. 15 Oct. 2008. Web. 7 Feb. 2011. <http://
watkins4engineering.wordpress.com/2008/10/15/students-design-and-build-cardboard-chairs/>.
"Why Use Cardboard." Cardboard Furniture Company | Cardboard Furniture for People on the Go. Web. 2 Feb.
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