DESIGN PROJECT #1 Cardboard Furniture Design Introduction to Engineering Design EDGSN 100 Section 003
PSU Engineers Design Team 3 Zachary Farr, personal.psu.edu/zaf5003,
[email protected] Kevin Grim, personal.psu.edu/kdg5101,
[email protected] Adam Johnson, personal.psu.edu/ajj5113,
[email protected]
Submitted to: Professor Berezniak Date: 2/23/2011 1
Spring 2011
DESIGN PROJECT 1 – CARDBOARD FURNITURE DESIGN
Table of Contents
1.0 Introduction……………………………………………………………………………………. 2.0 Mission Statement…………………………………………………………………………. 3.0 Customer Needs Analysis……………………………………….………………………. 4.0 External Research………………………………………….………………………………. 4.1 Library/online………………………………………….…………………….……. 4.2 Patent research………………………………………………….………………. 4.3 Benchmarking…………………………………….………………………………. 5.0 Target Specification……………….……………….……….……………………………. 6.0 Concept Generation………………………..…………….………………………………. 7.0 Concept Selection…………………………………………………………………..………. 8.0 Final Specification………………………………………………………………………..…. 9.0 Final Design……………………………………………………………………………….…… 10.0 Conclusions…………………………………………………………………………………… 11.0 References……………………………………………………………………………………
Page 3 Page 3 Page 3 Page 4 Page 4 Page 5 Page 5 Page 7 Page 7 Page 10 Page 12 Page 13 Page 18 Page 18
List of Tables Table 1 Table 2 Table 3 Table 4 Table 5 Table 6
Customer Needs Importance……….………………….……..…..… Page 4 Benchmarking of Three Products…………………………………..… Page 6 Target Specifications……………………………………………….……..… Page 7 Concept Screening Matrix……………………………………….……..… Page 11 Concept Selection Matrix……………………………………….……..… Page 12 Final Specifications……………………………………….………………..… Page 12
List of Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15
Cardboard Chair Prototype …………….………………….………..… Page 6 Ikea Poang Chair…..…………………………………………….………..… Page 6 Ikea Bernhard Chair.……….………………………………….………..… Page 6 Concept Sketches……………………………………………….………..… Page 8 Concept Sketches………………………………………………….………..… Page 9 Concept Model…………………………………………………….………..… Page 10 Top View….………………………………………………………….………..… Page 13 Front View………………………………………………………….………..… Page 14 Right Side View…………………………………………………….………..… Page 14 Isometric View…………………………………………………….………..… Page 15 Assembly Drawing……………………………………………….………..… Page 15 Tube Drawings…………………………………………………….………..… Page 16 Chair Side Drawing……………………………………………….………..… Page 16 Final Prototype…………………………………………………….………..… Page 17 Final Prototype…………………………………………………….………..… Page 17 2
Spring 2011
Abstract This report analyzes the design steps used in the design of a cardboard chair. Surveys of potential customers showed the chair needed to be easy to assemble ad move, as well as simple to store. Structural elements in “L” “O” and ““ shapes were then tested. We developed several concepts, eventually choosing a concept with two flat sides cut into the profile of a chair with cardboard tubes connecting them, forming the back and seat.
1.0 Introduction Chairs are used by nearly everybody nearly every day. We sit in them while we’re in class, we relax on them to watch television, and use them to do work in the office. We are so used to having chairs around all the time that we never stop to think about them. Our design takes the average chair and makes it a little more unique. The design we used made use of tubes for the seating and back portions, a unique design feature that makes our chair interesting and aesthetically pleasing. Our design process involved interviewing and surveying potential customers to gain a better idea of what they would like to see in a chair (See 3.0 Customer Needs Analysis). Our target consumer is the college-‐age student, who needs comfort on a budget, without sacrificing quality and usability. We used the data we learned from our surveys and from research to create several prototype designs, which we narrowed down to one final design (See 6.0 Concept Generation). We believe the engineering design process helped create a chair design that is both unique and functional.
2.0 Mission Statement
The goal of Team 3 was to create a cardboard chair that was functional in a dorm or student environment. The chair was to be easy to store and assemble/disassemble, but also cheap enough for students to purchase.
3.0 Customer Needs Analysis
Customer needs were established through the use of surveys and interviews of potential customers. Individuals were questioned on what they think would be a good feature of a cardboard chair and asked to explain how their ideas would be useful to buyers of the chair. The needs established by the potential customers were then compiled and used in the early design stages of the cardboard chair.
3
Spring 2011
No. 1 2 3 4 5 6 7 8 9 10 11
Cardboard chair Cardboard chair Cardboard chair Cardboard chair Cardboard chair Cardboard chair Cardboard chair Cardboard chair Cardboard chair Cardboard chair Cardboard chair
Table 1 Customer Needs Importance Table Need has a supportive, strong, and comfortable back can safely hold the weight of an average person is easy to disassemble and store looks aesthetically pleasing has a low cost is durable in an indoor environment is hard to tip over can be easily repaired or fixed Is environmentally-‐friendly creates minimal amount of waste during construction can be easily cleaned
Imp. 5 5 4 3 4 5 4 2 3 2 3
4.0 External Research Our search for chair designs yielded many original and unique designs. Many variations of the “generic chair” are available for purchase. The typical chair design features a back, seat, and four legs, and some have armrests. External research consisted of Literature Search, Patent Search, and Benchmarking chairs available on the market.
4.1 Literature Search
Chairs have been with humans for a very long time. Today we use them daily. The chair cannot be attributed to one person, as different people and cultures formed their own type of “chair” simultaneously. Early “chairs” could have included rocks, or simple structures made from logs. Some of the earliest chairs–using the word as we know it today–appeared in the Egyptian era, around 3000 BCE to 500 BCE. These chairs were influenced by designs originating from Asia and Europe. Chairs vary very much in their designs. The word “chair” encompasses anything that is essentially a seat that can be moved. In earlier times, chairs were reserved not for common people, but for higher classes such as kings, bishops, lords, and pharaohs. The majority of people were relegated to using stools or benches–usually without a back. The name “chair” comes from the latin word cathedra which shows the distinct relation between chair and the cathedral, or church. The simplest and earliest chair 4
Spring 2011
designs originated from X-‐shaped chairs (similar to today’s folding chairs) that appeared during the Roman era. The French are credited with the earliest designs of what we see today as a chair. They were the first to implement designs that were largely designed to be functional. The chairs from France were simple and easy to build. They worked hard to make the chair into something that would be comfortable and useful, while also being somewhat stylish. It was around this time that chairs with fabric seats began to appear, and designs began to incorporate fancy designs that were aesthetically pleasing, and also comfortable. Soon after the French redesigned the chair it became popular and construction moved to the factory around the 18th century. These chairs were handcrafted and often very ornate. They required a large amount of material, often involving large solid pieces of wood necessary for carving the design elements. These chairs became the basis for the modern chair, which as evolved considerably. Today chairs are made of many materials, even plastics and metals. Chairs now have many designs, some made for use in the office and some made more for display than seating.
4.2 Patent Search
A basic search for chair patents yields approximately 134 chairs. The patents all cover basic variations of chairs. The majority share the same features, with a simple back and seat, with four legs and arm rests. Some more creative designs do appear in the patents, though not many.
4.3 Benchmarking For our benchmarking portion of development, the chair was compared to two chairs currently on the market, the Ikea Poang Chair and the Ikea Bernhard chair. We compared the specifications of each chair, and ranked them on a scale of 1 to 5, 5 being the best. Our chair came in second place, which is decent considering the other two are commercial products made out of metals and plastics, as opposed to cardboard. Patent search yielded chairs of similar design and specifications to the Ikea chairs. Emphasis in the Benchmarking was placed on the weight supported and cost, with lesser emphasis placed on the other design features. Our design prototype fared well against the commercial comparison products.
5
Spring 2011
Table 2 Benchmarking of Three Products PSU Engineers -‐ Cardboard Chair Prototype
Weight
Selection Criteria
%
Ranking
Value
Weighted Score
Ikea Poang Chair Ranking
Ikea Bernhard Chair Weighted Score
Value
Ranking
Value
Weighted Score
Weight supported (lbs)
20%
3
~160 lbs
0.6
5
375 lbs
1
4
200 lbs
0.8
Cost ($)
20%
3
$78
0.6
2
$99
0.4
1
$139
0.2
Quality
10%
4
4
0.4
5
5
0.5
4
4
0.4
Aesthetics
10%
3
3
0.3
5
5
0.5
3
4
0.3
Weight
10%
5
5 lbs
0.5
3
23 lbs
0.3
4
16 lbs
0.4
Height
10%
5
36"
0.5
5
30 3/8"
0.5
5
30 3/8"
0.5
Depth
5
27 5/8"
0
5
32 1/4"
0
5
19 5/8"
0
Width
10%
5
21"
0.5
5
26 3/4"
0.5
5
17 3/4"
0.5
Total Score Rank
3.4
3.7
3.1
2
1
3
Figure 3 Ikea Bernhard Chair
Figure 1 Cardboard Chair Prototype
Figure 2Ikea Poang Chair
6
Spring 2011
5.0 Target Specification Our target specifications included design features that would be most relevant to the user. Cost, capacity, and quality were the most important factors in our target specifications. For cost, we exceeded the ideal price. In capacity, our estimated capacity (a conservative estimate) exceeds the marginal value, but does not exceed the ideal value. Other target specifications are exceeded in our design, including the dimension specifications. The target specifications represented a goal for our design to achieve, and a benchmark for us to meet. Table 3 Target Specifications Target Specs Feature Current Specs Ideal Marginal Cost
$78.00 <$85.00
<$100
Capacity
160lbs
>180lbs
>140lbs
Height
36"
>32"
>30"
Width
21"
>18"
>16"
Depth
27 5/8"
>24"
>22"
Ease of use
5 >4
Quality rating
4
4
3
4
4
3
Aestetics rating Lifetime
2 years (est)
18 months
>3
1 year
6.0 Concept Generation Concept development began with “boxing out” the basic chair shape. We decided on a simple chair, consisting of four legs and a back. Our first concepts just outlined the general shape. In Figure 4, the basic chair measurements were drawn. The dimensions of the seat and back were approximated, which we used in designing the general shape later in the development process (See Figure 5). The general shape design for our final concept is illustrated in Figure 5, where we started to develop what would become the basis for our two-‐sided chair with the back and seat formed out of cardboard tubes. Our sketches were instrumental in producing the first 7
Spring 2011
manila folder models which were used to develop the half-‐scale mock-‐up. These sketches aided us in developing what would become our final design.
Figure 4: Concept Sketches
8
Spring 2011
Figure 5 Concept Sketches 9
Spring 2011
7.0 Concept Selection
Each of our group members presented their design to the group. The three different concepts were largely similar, which helped in narrowing down the final design. Figure 6 shows an example of one of our designs, which was used as the basis for our final design. We analyzed each concept and looked at both the positive and negative aspects of it. We tried to use the positive aspects from each to produce a final design that would be a well-‐rounded product, featuring a strong, aesthetically pleasing, and original design. Two of our main concepts had slight variations, meaning we had a total of five different model concepts (See Table 4 and 5 below). The concept selection process allowed us to narrow down our final design, which we then modeled in SolidWorks and produced using cardboard.
Figure 6 Concept Model 10
Spring 2011
Selection Criteria
Table 4 Concept Screening Matrix Concepts A
B
C
D
E
Height
-‐
+
-‐
-‐
-‐
Width
-‐
0
0
+
0
Depth
+
0
0
0
-‐
Aesthetics
0
+
-‐
+
+
Ergonomics
0
+
+
-‐
-‐
Cost
0
0
+
-‐
0
Ease of use
+
0
+
0
0
Quality
0
+
0
0
0
Sum +’s
2
4
3
2
1
Sum 0’s
4
4
3
3
4
Sum –‘s
2
0
2
3
3
Net Score
0
4
1
-‐1
-‐2
Rank
3
1
2
4
5
Yes
Yes
Yes
No
No
Continue?
11
Spring 2011
Table 5 Concept Selection Matrix Wt Selection Criteria
%
Team 3 Cardboard Chair Ranking
Concept A
Wt’ed
Value
Score
Ranking
Value
Concept B Wt’ed Score
Ranking
Value
Wt’ed Score
Weight supported (lbs)
20%
3
~160lbs
0.6
2
~180lbs
0.4
3
~160lbs
0.6
Cost ($)
20%
4
~$80
0.8
3
~$100
0.6
4
~80
0.8
Ergonomics
20%
4
4
0.8
3
3
0.6
3
3
0.6
Ease of Use
20%
5
5
1
4
4
0.8
4
4
0.8
Aesthetics
10%
5
5
0.5
3
3
0.3
4
4
0.4
Quality
10%
5
5
0.5
4
4
0.4
5
5
0.5
Total Score
4.2
3.1
3.7
1
3
2
Yes
No
No
Rank Continue?
8.0 Final Specifications The target specifications were the guidelines for creating our final specifications. We took the most important aspects of the design, which we put into Table 6. We wanted to keep cost as low as possible since the average college student does not have excess money to spend on a chair. Our product weight was kept low due to the usage of cardboard, a naturally light material. The overall size dimensions are similar to those of the average desk chair. The incorporation of tubes for the seat and back provides a unique difference between our chair and the typical chair available on the market. The capacity of our chair is similar to chairs available on the market. Table 6 Final Specifications Feature
Current Specs
New Specs
Cost Weight Tube Diameter Width Height Depth Capacity
$79 Approx. 5lbs 3” 21” 36” 27 5/8” ~160lbs
<$70.00 5lbs 3” 21” 36” <28” ~180lbs
12
Spring 2011
9.0 Final Design The final design features a cardboard chair composed of two sides and tubes forming the seat and back. The usage of strong cardboard sides provides the vertical support necessary to have a chair the same height as an average chair, while also providing the aesthetically pleasing looks of the chair. Using tubes, we were able to make a seating surface that is unique from most chairs available today. The tubes also serve to provide the horizontal structure that sustains the load of a person sitting on the chair. In addition, the tubes add to the aesthetic appeal of the chair.
Figure 7 Top View
13
Spring 2011
Figure 8 Front View
Figure 9 Right-‐side View 14
Spring 2011
Figure 10 Isometric View
Figure 11 – Assembly Drawing 15
Spring 2011
Figure 12 – Tube Drawings
Figure 13 – Chair Side Drawings 16
Spring 2011
Figure 14 – Final Prototype
Figure 15 – Final Prototype 17
Spring 2011
10.0 Conclusions Our project was successful. Our prototype design represents the culmination of design work and perfection. A full-‐scale model could be built using our plans and drawings. We believe our chair meets the design requirements set forth in the project, as well as the specifications we intended it to meet. Theoretically, we believe this design could be sold on the market, and possibly adapted to other materials for easy marketability. We were able to successfully utilize the design process to research and learn about cardboard chair design. Using the ideas we formed from our research, we were able to create concepts that were then used to make our final concept, which developed into our final design. This design was utilized in creating a ½ scale model for presentation purposes.
11.0 References Berry, Jennifer. "The Revival of the Cardboard Chair." earth911.com. N.p., 2/11/2011. Web. 18 Feb 2011. Blackburn, Graham. "A Short History of Chairs." FineWoodWorking.com. N.p., n.d. Web. 20 Feb 2011. "Cardboard Chairs 101." Instructables.com. N.p., n.d. Web. 17 Feb 2011. "Cardboard Folders." DesignBoom.com. N.p., n.d. Web. 17 Feb 2011. "History's 40 Chairs." SawDustMaking.com. N.p., n.d. Web. 20 Feb 2011.
18
Spring 2011
