Driver’s Dream Cup Holder
Nick Magnuski
Sophia Reyes
Steve Strine
Marcy Urbance
The intent of this project is to design a cup holder for the center console of a midsize car that is well-crafted,
versatile across vehicle interiors, and holds a wide variety of cups. The optimal design will maximize profit by
minimizing manufacturing cost, maximizing customer satisfaction, and maximizing segment market share. The end
product will strike a balance between simplicity of design and ability to accommodate a range of cup and bottle
sizes. Our proposed cup holder implements spring-loaded blocks for a variable gripping height in a relatively
simple design that is easy to use.
TABLE OF CONTENTS
1.Introduction.................................................................................................................................. 4
1.1.1 Definition of Need ............................................................................................................. 4
1.1.2 Background/Previous Designs ........................................................................................... 4
1.1.3 Design Objectives .............................................................................................................. 7
1.1.4 Design Decisions ............................................................................................................... 7
1.2 Product Development Process .............................................................................................. 8
2. Concept Generation .................................................................................................................... 8
2.1 Concept Selection Process .................................................................................................... 8
2.3 Final Design Concept.......................................................................................................... 12
2.4 Prototype Description ......................................................................................................... 13
3. Engineering Analysis ................................................................................................................ 15
3.1 Design Variables................................................................................................................. 15
3.2 Engineering Models ............................................................................................................ 16
3.3 Engineering Optimization Study......................................................................................... 17
4. Economic Analysis ................................................................................................................... 26
5. Marketing Analysis................................................................................................................... 31
6. Additional Design Consideration.............................................................................................. 34
6.2 Ergonomics ......................................................................................................................... 36
7. Final Design Recommendations ............................................................................................... 36
8. Conclusion ................................................................................................................................ 37
References..................................................................................................................................... 38
Appendix B: QFD Chart ............................................................................................................... 40
Appendix C: Gantt Charts............................................................................................................ 41
Appendix E: Design Flowchart..................................................................................................... 43
Appendix F: Technical Analysis................................................................................................... 44
Appendix G: Engineering Model.................................................................................................. 45
Appendix H: Survey ..................................................................................................................... 47
Appendix I: Model Comparison ................................................................................................... 73
Appendix J: Business Plan............................................................................................................ 74
Business Opportunity................................................................................................................ 74
Financial Data ........................................................................................................................... 75
Supporting Documents.............................................................................................................. 76
2
Nomenclature
Outer Radius
Inner Radius
Height block
Height Cup holder
Height of Total Device
R2
R1
Hb
Hc
Ht
Number of gaps
Gap size
Gap variation
Profit
Demand
Ng
gs
gv
π
Q
Length of outside of block
Length of inside of block
Removable bottom inner radius
Removable bottom Outer radius
Removable Bottom arc length of opening
Force to wedge bottom
Force to pull bottom
b
a
Rb1
Rb2
Lb
Fwedge
Fpull
Microeconomic Demand
Cost
Fixed Cost
Variable Cost
Cost of wage
Cost of materials
Price
Qe
C
Cf
Cv
Cw
Cm
P
Stress
σ
Total market potential
θ
Friction Force
µ
Price elasticity
λP
Circumferential distance between blocks s
Performance Cupholding
Pc
Performance Ease of Use
Pe
Ergonomic Performance
E
Tip Angle
Фhc
Versitality
V
Base wall thickness
Tw
Vector of design characteristic elasticities λd
Vector of design variables
α
Wage line worker
Wl
Wage supervisor
Ws
# of blocks
Z1
Bottom?
Z2
Cup holder height
Z3
3
1. Introduction
1.1.1 Definition of Need
Johnson Controls Incorporated (JCI) has suggested that we explore an improved design including
a look at craftsmanship, selected from an automotive interior. We have chosen to improve the
design of a cup holder. We are designing a cup holder for the driver that will automatically
adjust to container size. A new cup holder needs to be designed to adjust to various containers
because there has been an increase in soft drink serving size by 52% from 1977 to 1996 resulting
in bigger cups being used [2]. Therefore, there is now a greater range of cups available in the
market and much of which are bigger then what the average cup holder will hold. The design
will be optimized for specific engineering components and also to maximize profit. The cup
holder also needs to provide versatility of use in various vehicles as well as multiple functions
extending beyond a simple cup holder. Overall, we are designing a well-crafted cup holder that
is easy to manufacture, service, and dispose of, to hold a wide variety of cups while not
interfering with driving and other controls within the center console.
1.1.2 Background/Previous Designs
Cup holders can be placed in two general categories: permanent and temporary. Permanent cup
holders are available for use at any time, while temporary cup holders can be stowed away when
not in use. A permanent cup holder for the driver is the primary focus of our design. In order to
determine the current state of the art of cup holders different designs were researched by looking
at various car cup holders, talking to users and car dealers, and conducting a patent search.
To determine the current problems consumers have with their cup holder’s informal interviews
with family and friends were conducted. Some of the responses to these interviews are shown in
Appendix A. The major problems that were gathered from these discussions were cups tipping,
too small or too large for specific cups, and in the way of controls.
The Honda Accord cup holders were made adjustable by using tab devices around the cup shown
in Figure 1. The Volkswagen Passat also had a similar type of design. The problem with these
cup holders is that a small water bottle is not gripped by the tabs and will tip. Also the tabs in
the Accord cup holder where very easy to push; therefore, a cup could easily tip back and forth
within the holder. On the other hand the Passat tabs were very tight, causing Styrofoam cups to
become grooved by the tabs. In this design obtaining the correct balance of tightness for the
grips is a difficult issue.
4
Figure 1: Honda Accord Cup Holders [3]
A self-adjustable cup holder, US patent # 6,637,709 is another solution to cup size variability, a
side view of this cup holder mechanism is show in Figure 2. The sides of the cup holder expand
when a larger cup is slid into the cup holder. However, this cup holder does not support cups
smaller then the original holder size and also top-heavy cups will tend to tip because the cup
holder only grips the bottom of the cup [1].
Figure 2: Self-Adjustable Cup Holder US patent # 6,637,709
The cup holder shown in Figure 3 also provides some adjustability. The expanding arms of the
cup holder are flimsy and can easily be caught on and broken off.
5
Figure 3: Cup Holder
A solution to an existing cup holder problem is to buy a cup holder adapter or to buy another cup
holder to attach elsewhere. One example of an attachable cup holder is shown in Figure 4. This
cup holder can be secured to the drivers’ side window by way of a suction cup. The adjustability
is provided by having one wall slide in and out that locks in place (Patent # 5,573,214). Having
an additional add on cup holder creates many problems, such as in this design if the cup weights
to much the suction cup could release. Also the adjustment requires the user to use both hands
for adjustment which could interfere with driving [3].
Figure 4: Window Cup Holder (Patent 5,573,214)
A more functional cup holder for the driver needs to be developed. Current cup holders only fit
certain cups resulting in tipping causing inconveniences and distractions to the driver.
6
1.1.3 Design Objectives
Our proposed design must satisfy the following specifications and performance:
• Accommodate a variety of sized cups ranging from a Nalgene water bottle to a pop can.
• Be easy to use, in that no directions would be required to operate it efficiently
• Have high performance quality
• Manufacturing ease; minimal parts, ease of assembly
• Versatility for use in various vehicle makes and models
• Applicable for multiple uses: change tray, cell phone holder, etc.
• Visually appealing, finish, and aesthetics
• Ease of Maintenance and cleaning
• Low cost to manufacture
• Safe for hands and fingers
• Durability – breakage and ring tension
Appendix B contains a Quality Function Deployment (QFD) worksheet that quantifies these
specific design criterions and provides a matrix of correlations.
1.1.4 Design Decisions
A number of important decisions need to be made at the design stage of the process. The
relevant decisions in regards to a cup holder can be generally divided into dealing with spatial
and placement issues, and specific cup holder functionality.
The first category is spatial and placement. The location of the cup holder needs to be decided,
and for this project such a decision space is contained to the center console. The exact volume a
cup holder occupies can typically be classified as temporary or permanent. In other words, the
holder can be a non-moveable feature of the interior, or it can slide, fold, or otherwise extend out
from either full occlusion or to accommodate larger cups. Some examples of temporary space
occupied by a cup holder are knee space, dashboard space, and arm rest space.
Still within the same category, but dealing more with human interaction, are the issues of target
user and task interference. A designer needs to decide whether the cup holder(s) will be used by
the driver exclusively, the driver mostly, or the driver and passenger equally. Essentially, the
priority of use needs to be determined. Also, the spatial location of the cup holder, especially if
it is temporary, may block some tasks the driver might be performing while driving or at rest.
The designer has to decide which tasks, such as operating radio controls or using the ashtray,
might need to be performed in parallel with or in place of cup holder use.
The second category is specific cup holder functionality. Here the designer decides both what
range of uses to accommodate and how to achieve this. The spectrum of cup sizes that fit in the
cup holder is determined, as is perhaps a few selected cup shapes that are most common for the
target audience. Similarly, the climate and driver aggression ranges are determined. Also, the
variety of other objects the cup holder might store is determined. The designer then determines
how to physically hold the cups in place. This is primarily a geometric problem, but includes
deciding whether to make room for mug handles and how high to grip cups and bottles when in
the cup holder.
7
The designer also decides if the cup holding mechanism will be automatic or user-activated. An
automatic system, which might be passive with no moving parts, simply holds the object when
placed in and releases when pulled out. A user-activated system can require moving the cup
holder into temporary space and/or adjustment to tailor the fit to the desired object size. The
designer must then determine if such operation requires power or other forms of energy.
Associated with these decisions is a tradeoff with simplicity, affecting both manufacturing and
user cognitive requirements, and safety, particularly the possibility of small children getting
caught in the mechanism.
1.2 Product Development Process
Shown in Appendix E, is the product development process that was used in the design of the cup
holder. At different points throughout the process iterations were needed. When narrowing
down the possible solutions more ideas were thought of and the brainstorming phase was
revisited. Also during the refining and narrowing solutions stage the design requirements needed
to be rethought to make sure the most important objectives would be able to be met and other
objectives were sacrificed. After the preliminary design was chosen it failed and was rejected in
the verify concept step; therefore, the process began again at the brainstorm stage. Once the new
design was chosen and a prototype was made, many iterations occurred between further analysis
& modeling and refining the design before the second prototype was created. Further steps can
be taken to create a preliminary production model and move onto the production stages if the
production model is approved. The Gantt chart that was followed to complete the design
development process is shown in, Appendix C.
2. Concept Generation
2.1 Concept Selection Process
To evaluate the tradeoffs in our possible designs, a Pugh matrix was created (see Appendix D).
Five possible solution concepts and our final design concept were generated and are explained
below. Each concept was compared based on weights for each of the following design criteria:
• Durability
• Cost
• Ease of Manufacturing
• Universality
• Safety
• Adjustability
• Required user interaction
• Novelty of design
• Cleaning capability
• Versatility
• Reliability
• Cup Hugging Ability
• Quality Feel
8
After each concept was scored on each criterion the design with the highest score was chosen.
The design concepts that were compared are explained and sketches are shown below.
2.2 Alternative Concepts
Design six is the simplest of all the cup holders we created, shown in Figure 5. This prototype
utilizes four torsion springs as the source of gripping power for the four cup grips extending from
the side of the cup holder. The torsion springs are mounted on rods directly below the gripping
rods. When a cup is placed in the holder the grips rotate inward about the support rods (just
above the center of the torsion spring) near the top of the cup. During this rotation the torsion
springs apply a horizontal force to the side of the cup holder and an equal force to the base of the
grips. When the base of the cup reaches the bottom of the cup holder the grips apply horizontal
forces on the sides of the cup preventing the cup from moving or tipping over while the vehicle
is moving. When a large cup or bottle is placed in the holder the torsion springs are fully
compressed and the grips are rotated inward 90 degrees and reside in a cavity on the side of the
holder. Upon removal of a cup the grips spring back to their original horizontal position. To
clean the cup holder, the grips would be rotated upward above the horizontal position. This is
possible because the torsion spring is only applying force to the base of the rods, not the top.
This design is both simple and easy to manufacture. However, the design is so simple it may
break easily and also be perceived as cheap.
Figure 5: Design Six
Design five involves the use of gravity and a gear train for operation and is shown in Figure 6.
When a cup is placed in the holder the weight of the cup pushes the false bottom downward. A
notched rod attached to the center of the false bottom also moves downward through the actual
base of the cup holder. As the notched rod moves downward it contacts a cylindrical gear
located below the actual base of the cup holder causing it to rotate counterclockwise. Two
notched rods then interface with the rotating cylindrical gear, one on the top and one on the
bottom. The notched rods are each a part of a c-shaped device that moves horizontally inward as
the gear rotates counter clockwise. The top portions of each c-shaped device act as grips for the
cup being put in the holder by sliding through sides of the top of the cup holder and grasping the
cups. When the cup is removed four compression springs below the base of the false bottom
cause it to rise vertically rotating the cylindrical gear clockwise, allowing the c-shaped rods to
move outward releasing the cup holder. This idea is unique because a cup’s weight is used to
hold it in place. This results in less work for the user and a more sophisticated feel to the cup
9
holder. A few disadvantages of the design is that if the cup being place in the holder isn’t heavy
enough to overcome the vertical force of the compression springs nothing will happen and the
complicated manufacturing process involved.
Figure 6: Design Five
The fourth design is shown in Figure 7 it also involved the use of compression springs. When a
cup is placed in the holder two shoe-horn shaped grips accept the cup and adjust according to the
cup size. The grips adjust position by moving horizontally towards the holder walls and also
through the vertical rotation of the grip. The back of each grip pivots on two horizontal rods
which are connected by a compression spring to a lateral support mounted on the outside of the
holder. When the grips move toward the holder walls the rods connected to the grips compress
the springs attached to them creating an equal and opposite horizontal force on both sides of the
cup. When the cup is removed the springs decompress returning the grips to their original
position. An advantage of this cup holder is the ability of the grips to rotate and fit to the contour
of the cup being placed in the holder. The simple design without many components make the
cup holder cheap and easy to manufacture. One disadvantage is items may get stuck beneath the
horizontal rods. It is also possible that the horizontal rods may break if a cup was placed in
between a grip and the wall of the cup holder or on the grips with too much vertical force.
10
Figure 7: Design Four
The third design, Figure 8, requires no mechanical mechanisms in the functioning of the cup
holder. It is designed to provide adjustability and support for a variety of beverage containers by
utilizing elastic material. Traditional cup holders occupy a cylindrical shape around three inches
in depth inside the center console. This holder utilizes the contour of the console between the
gear shifter and the armrest between the seats. The height of the console at the gear shifter is
lower than it is at the armrest so there is normally a gradient between the two locations. This
holder would require a four-inch deep semi-cylindrical shape to be contoured into the gradient in
the center console. A piece of leather material would then be attached to the bottom and side
edges of this half cylinder forming a pouch. The leather material would have horizontal bands
sewn into it so that the leather could expand depending upon the size of container placed in the
holder. The elastic bands would also provide horizontal support to all containers ensuring they
did not tip over or fall out when the vehicle was in motion. A positive attribute of the design is
the elastic material will always adjust to the correct size of the container being placed in it.
Making it very versatile, therefore it could be used for things such as change and cell phones
without any risk of getting them caught. However, the elastic material may also make the design
feel cheap because it may wear out too quickly. It is also possible that the leather material could
be cut or ripped.
Figure 8: Design Three
11
The second design, Figure 9, employees’ circular rings and an elastic force to hold containers.
There are two circular rings positioned 90 degrees apart used to support the containers inside the
cup holder frame. Each ring has two mounting rods located 180 degrees apart from each other
on the outside of the ring which mount into holes on the outside of the cup holder frame. The
mounting rods of the smaller ring go through holes in the mounting rods of the larger ring. Both
sets of mounting rings extend through the outside of the cup holder frame to the outside of the
cup holder and have a short bar perpendicular to the rod centered on it. There are also two
support rods, one located above the mounting rods and one located below the mounting rods, on
the outside of the cup holder. On each of the support rods there are two perpendicular bars; one
is located in line with the bar on the large ring mounting rod and one for the small ring. Elastic
bands are placed on the bars on each mounting rod and connected to the support bars above and
below them to ensure that the small and large ring rotate in an opposite directions. The static
position for each ring is regulated by stops located on the bottom of the holder. The stops only
allow the rings to rotate far enough so that they are separated at the top by a distance large
enough to accept a pop can or a small water bottle. When a larger drink container is placed in
the holder it pushes down on both rings causing them to rotate in opposite directions until the
gap between them is large enough to accept the container. When the container slides between
the rings the rings exert an inward force on the container attempting to return the rings to their
initial static position, this is due to the elastic bands applying force to the mounting rods. It
supports, adjusts to all container sizes and is very universal because of its compact size;
however, the design would be a complicated manufacturing process that would result in
moderate production costs. The design also fails to grip taller cups at a higher location than
shorter cups.
Figure 9: Design Two
2.3 Final Design Concept
The first design, Figure 10, was created by combining some of the concepts integrated into the
sixth and fifth designs. This design uses three grips surrounding the cup that can travel in the
vertical direction to adjust to support a variety of containers. Each grip is a hollow trapezoid.
The hollow space inside each grip allows for a compression spring to fit inside. This spring is in
turn connected to the base of a cavity designed to accept the vertically traveling grip. When
12
there is no force on a grip the fully extended compression spring supports the weight of the grip
maintaining the grip in a full upright position. The grips are positioned relative to each other so
that a pop can or thin water bottle may be placed between them without applying force to the top
of any grip. However if a larger container is placed in the holder its size can be accommodated
by placing it on top of anywhere from one to all three of the grips. The weight of the container
will apply a downward force to the top of a grip overcoming the upward force from the
compression spring causing the grips to move down into their cavities and out of the cup holding
areas. Any grips that remain in their original position will act as the sides of the cup holder by
applying a supporting horizontal force to the sides of the container. When the container is
removed the vertical force applied by the compression springs will return them to their original
position. The advantages of this design are the user doesn’t have to do a great amount of work to
use it and it provides good lateral support to each container. However, this holder may be hard
to keep clean and its depth of occupancy in the console may make it unusable for some cars.
Also, if a lightweight container was placed on the grips it may not have enough vertical force to
compress the springs or it might completely pop out of the cup holder if a large force was applied
and then released.
Figure 10: Design One
2.4 Prototype Description
The final design was first verified by making a quick prototype made of planting foam. This
prototype is shown in Figure 11.
13
Figure 11: Foam Prototype
After the design was verified it was modeled and analyzed in ADAMS software and is shown in
Figure 12.
Figure 12: ADAMS Drawing
Finally a working prototype was constructed in the machine shop in through the following
processes. First the outside of the cup holder was made from PVC pipe and cut to dimension
using a band-saw. The removable bottom and base of the holder were then designed in BobCAD and created out of Plexiglas using a laser cuter. Next springs were created using a device
that tensioned and coiled small diameter music wire because the ones our design required could
not be purchased. Following the creation of springs, three screws were screwed in the holder
base and then fitted with hollow rods of Plexiglas to be used as spring supports. The buttons and
removable bottom supports were then made by lathing, boring, and band-sawing a piece of round
UHMW polyethylene. After the buttons were created a hole for the spring and spring support
14
was drilled in each one of them. Next the removable bottom supports were attached to the holder
base by screws. Final assembly included placing the springs in the drilled out button cavities,
placing each button on a spring support, and then placing the PVC around the interior holder
pieces.
Some of the major problems encountered in prototyping were making the springs, and cutting the
buttons properly to fit their cavities. Creating springs with a coefficient of stiffness that allowed
them to support one button, but also be forced down by an empty container was difficult and not
fully achieved. While creating the springs it was a challenge to maintain proper tension and
spacing for each coil to produce the ideal product. When the buttons were cut on the band-saw
there were problems keeping the button material flush against the band-saw table because of the
torque on the piece from the cutting blade. This resulted in some crooked button pieces which
had to be re-cut and sanded so that they we fit and function properly in their cavities. After
overcoming obstacles such as these the final prototype became a working device that
accomplished most of its desired design objectives with great consistency. A picture of the final
prototype can be seen in Figure 13.
Figure 13: Final Prototype
3. Engineering Analysis
3.1 Design Variables
In this project we have limited our cup holder to a permanent space in the center console, and
have selected a preliminary functional design. Therefore the primary design variables concern
the cup holder geometry and material selection.
15
Geometry variables are as follows:
• Depth and diameter of the base hole
• Depth of cup holding space
• Inner diameter made by blocks
• Height and width of the blocks
• Radial spacing and arrangement of the blocks
• Removable bottom dimensions
Material selection variables are as follows:
• Block material
• Spring tension
Other variables we have considered but left as parameters might be investigated in a more
technical analysis or for specific manufacturing concerns. Some of these include:
• Location of base hole within the console
• Block thickness
• Spring free and compressed length
• Pull tab dimensions
• Curvature of true bottom
• Height and diameter of spring post
• Block color
3.2 Engineering Models
The four engineering models identified for analysis in this project are mechanics, dynamics,
ergonomics, and craftsmanship. Mechanics analysis will be used to examine the strength and
durability of the sliding blocks and springs. The blocks will be under stress laterally when a cup
or bottle is wedged in, and will experience a number of distributed and point loads when an
object pushes them downwards. The block surface friction with the cups could also be
considered, as well as spring strength.
Models from dynamics will help assess block geometry, spring strength, and cup holder
performance when the car is in motion. The block height and width, listed as design variables
above, will be partially dependent on the optimal gripping height of the determined range of
cups. This, in turn, will depend on a 2DOF analysis of lateral forces likely to be experienced
during normal driving. The spring choice will also impact the kinetic energy stored when a user
pushes blocks down with a cup.
Ergonomic studies will ensure proper interface with the driver and passenger. Human “down
strength” will be evaluated in determining the stiffness of the springs within the blocks. The cup
holder mechanism needs to be examined with respect to child safety, for example to prevent a
child’s hand from getting stuck.
16
Craftsmanship metrics should also guide the design of the cup holder. To allow a seamless
integration with the visual flow of the cockpit, the cup holder geometry and material selection
will need to be considered. As these are product characteristics (and design variables in this
project), the relevant perceived attributes will need to be identified and matched with customer
input from the research phase.
3.3 Engineering Optimization Study
The optimal cup holder will ideally fulfill the many design requirements listed previously page 7.
However, since most of the requirements stated are qualitative in nature, and the analytic
approach to design taken here dictates quantitative variables, parameters, and overall measures of
requirement satisfaction, the quantitative and qualitative must be bridged. The first step is to
consider the objectives of the cup holder project from an engineering standpoint. The several
design requirements can be generally grouped into the following five categories:
1.
2.
3.
4.
5.
Performance (Cup Holding)
Performance (Ease of Use)
Ergonomics
Versatility
Craftsmanship
To avoid any confusion in later text, the term versatility is taken to mean ease with which the cup
holder can be mounted without modifications in various vehicles. While these objective
categories are still highly qualitative, they will provide a context for the following discussion of
model variables and parameters.
The geometry alone of a cup holder such as ours contains dozens of dimensions that could be
treated as variables. The relevant variables can be extracted by referring again to the QFD in
Appendix B. Looking at the normalized importance scores, it can be seen cup holder width and
depth are key, as are block dimensions. Also, to capture ergonomic and craftsmanship
characteristics, removable bottom dimensions will be considered. Thus there are eight variables
in this model:
Table 1: Design Variables
VARIABLES
Outer Radius
Inner Radius
Height Cup holder
Length of outside of block
Length of inside of block
removable bottom inner radius
removable bottom Outer radius
Removable Bottom arc length of opening
name
R2
R1
Hc
b
a
Rb1
Rb2
Lb
value
1.975
1.375
4
0.875
0.75
1.38
1.81
0.88
unit
inch
inch
inch
inch
inch
inch
inch
inch
Shown are nominal values, as well as units. The short list of variables is made up for by an
extensive list of parameters:
17
Table 2: Design Parameters
PARAMETERS
Nalgene Radius
Pop can Radius
Height of Nalgene
Height of Pop Can
95% Male Hand circumference
Finger Thickness
Finger Breadth
Thumb Breadth
Hand Breadth
Diameter of dime
Vertical Force applied on block (by user)
Horizontal Force (by vehicle)
Sigma_yield material
Sigma_compressive@10%compression
plastic coefficient of friction
Max Pull force on tab 5% Women ages 21-30
Number of Blocks
number of user-operated parts
number of incorrect container configurations
base wall thickness
Radius of sides of block
Depth of Block into outer cupholder
Radius of curvature of bottom
Spring Post Height
Spring Post Diameter
Spring Diameter
Removable bottom thickness
Underhang at block fully up
Snap on Top Outer Radius (R2 + d + (1/16))
Snap on Top Inner Radius
Snap on Top depth into cup holder
tab width
tab length
name
Rnalgene
Rpop
Hnalgene
Hpop
Cm
Tf
Bf
Bt
Bh
Dd
Fv
Fh
sigma_yield
sigma_c
mu_p
Fmax_tab
Nb
Np
Ni
Tw
Rb
d
Rbt
sph
spd
Ds
tb
Hh
Rs2
Rs1
Hs
tw
tl
value
1.75
1.25
8
4.75
12.5
0.6
0.9
1.04
3.8
0.75
5
1.37
4350
6750
0.55
8.16
3
4
4
0.25
0.75
0.125
3
1
0.375
0.5
0.25
0.25
1.98
1.3
0.5
0.5
1
unit
inch
inch
inch
inch
inch
inch
inch
inch
inch
inch
lbs
lbf
psi
psi
none
lbf
#
#
#
inch
in
inch
inch
inch
inch
inch
inch
inch
inch
inch
inch
inch
inch
Not all are relevant to the optimization model, such as snap-on top dimensions, but are included
for the sake of design completeness.
Certain variables and parameters determine the following dependent variables, which are used to
calculated objective function terms:
Table 3: Dependent Variables
18
DEPENDENT VARIABLES
name
Approximated Area of block, A= ((b+a)/2)* (RA
Inner Circumference
C1
Outer Circumference
C2
circumferential distance between blocks
s
tab pull force
Fpull
number of gaps
Ng
gap size
gs
gap variation
gv
Height block
Hb
Height of Total Device
Ht
value
0.59
8.64
12.41
3.24
0
19
0
0
4.25
8.5
unit
inch^2
inch
inch
inch
lbf
#
inch
inch
inch
inch
Tab pull force is derived as follows:
A wedge force can be produced in the removable bottom if Rb2>R2:
⎛ R − Rb 2
Fwedge = σ c ⎜⎜ 2
⎝ Rb 2
⎞
⎟⎟(t b s )
⎠
The pull force is in turn calculated as:
F pull = µ c Fwedge
Gap count, size, and variation are functions mainly of the number of blocks, and the tolerance
between the removable bottom and the block outer perimeter. For example,
gap size = max[(Lb-b),(R1-Rb1)]
Next the model constraints must be determined. Using a Nalgene bottle and a pop can as two
cup holding design standards, the first constraints are:
outer radius >= Nalgene radius + tolerance
inner radius >= pop can radius + tolerance
where the tolerance is assumed one eighth inch. To avoid making the unit too wide,
outer radius <= 2.25in
Also, dimensionally,
outer radius >= inner radius
inner radius >= 0
Cup holder height is also constrained from above:
19
H c <=
H na lg ene
2
For functionality the block dimensions are constrained as follows:
a >= 0
b >= 0.25in
C
a <= 1
3
a <= C1/3
a <= b – tolerance
a >= dime diameter
s >= 0
Removable bottom dimensions are constrained as follows:
Rb1 <= R1
Rb1 >= 0.5in
Rb2 >= R1
Rb2 <= R2
Lb >= b
Finally, ergonomic concerns give these constraints:
R2-R1 >= finger thickness
Fpull <= max pull force
sigma <= sigmayield
The above constraints are summarized and put in negative-null form in the table below:
Table 4: Constraints
20
CONSTRAINTS
Outer Radius > Nalgene Radius + (1/8)
Inner Radius > Pop Can Radius + (1/8)
R2<=2.25
R2>=R1
R1>=0
Hc<=Hnalgene/2
a>=0
b>=0.25
a< 1/3 of inner circumference
a<b-(1/8)
a>=dime diameter
s>=0
Rb1<=R1
Rb1>=0.5
Rb2>=R1
Rb2<=R2
Lb>=b
R2-R1>= Finger thickness
Fpull<=Max Pull force
Sigma<= Sigma_yield
name
Rnalgene+(1/8)-R2<0
Rpop+(1/8)-R1<0
R2-2.25<=0
R1-R2<=0
-R1<=0
Hc-Hnalgene/2<=0
-a<=0
0.25-b<=0
a-C1/3<0
a-b+(1/8)<0
Dd-a<=0
-s<=0
Rb1-R1<=0
0.5-Rb1<=0
R1-Rb2<=0
Rb2-R2<=0
b-Lb<=0
Tf-(R2-R1)<=0
Fpull-Fmax_tab<=0
sigma-sigma_yield<=0
With all model variables, parameters, and constraints outlined, the objective function can be
derived. The most consequential objective of the cup holder is clearly to hold cups well. To
simplify analysis of cup holding performance, the height of the cup holder, the inner diameter of
the casing for the cup holder and the thickness of the gripping blocks were considered. In order
to get some sense of which height, diameter, and thickness produced the best cup holding
properties we ran an engineering model using Adams.
Adams was used to create our basic cup holder design for three different types of beverage
containers. Because the gripping diameter of our cup holder changes with the size of the
container by displacing the gripping blocks downward, it was important that we analyzed the
performance of the holder for three different scenarios. The three scenarios analyzed were all
three blocks being displaced, one block being displaced, and none of the blocks being displaced.
The beverage containers used for these scenarios were a Nalgene Bottle when all three blocks
were pushed down, a medium coffee cup when two were pushed down, and a soda can when
none were pushed down. For each of the three situations a different holder was created in
Adams to represent the gripping ability of our design on each container.
For each scenario the variable dimensions were changed three times each and the holder was
analyzed at a 0.6g acceleration to determine how well it gripped the container. (A nominal value
used for the maximum acceleration or cornering force that a cup would undergo while in a car
under normal (not excessively aggressive) driving conditions was 0.6g or about 19.32 ft/(s2)).
The variable dimensions for the three-blocks-down scenario were height and inner casing
diameter of the holder, for the one-block-down and no-blocks-down scenarios the variables were
height and gripping block thickness. The tip angle of each container was measured for every
combination of design variables to quantify how well they combined to grip the container. Tip
angle for each container was determined by placing a marker at the center of the bottom diameter
21
and plotting the movement of the marker in the vertical direction during acceleration. The
maximum vertical displacement for each container was then used in combination with its base
diameter to quantify a maximum tipping angle.
Figure 14: Performance Model Diagram
Rear
Highest
Contact
Point
Vertical
Base
Tip
The data produced from completing this simulation was analyzed to determine if there is the
general effect that changing each of the design variables had on the tip angle of each container.
The general results for the scenarios were that as holder height increases and the inner diameter
of the holder’s gripping surface becomes closer to the maximum outside diameter of the
container, less tip angle occurs. We treated tip angle as a measurement of how much rotational
momentum the container has to flip out of the holder when a hard deceleration occurs.
Rotational momentum is important because when the container hits the inner edge of the holder
the horizontal momentum from mass in the container that is above the highest contact point
between the container and the holder will translate to rotational momentum. The rotational
momentum then causes the container to rotate around the highest contact point between the
holder and container, leading to the tip angle. If the point of contact between the holder and
container is too low the rotational momentum will cause the container to rotate out of the
container. A tight fit inner diameter helps prevent rotation of the container out of the holder
because the back end of the container contacts the back edge of the holder creating a counter
torque to offset some of the rotational momentum.
In order to complete an engineering analysis with the data obtained we plotted tip angle vs. both
inner gripping diameter and holder height. For each scenario tested we used linear regression
analysis to determine a best fit line for tip angle vs. holder height as inner gripping diameter
varied, and for tip angle vs. inner gripping diameter as holder height varied. Plots of these
scenarios are given here:
Figure 15: Tip Angle Plot
22
tan(tip angle) vs. Hc
0.18
0.16
0.14
nalgene1
0.12
Pop Can
0.1
0.08
Coffee Cup
nalgene2
0.06
nalgene3
0.04
0.02
0
0
1
2
3
4
5
Hc
Figure 16: Tip Angle Plot
lateral tip vs. D2
0.18
0.16
0.14
0.12
Nalgene
0.1
0.08
Coffee Cup
0.06
0.04
0.02
0
3.5
3.7
3.9
4.1
4.3
4.5
4.7
D2
Figure 17: Tip Angle Plot
lateral tip vs. D1
0.1
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0
Pop Can
Coffee Cup
2.5
2.7
2.9
3.1
3.3
3.5
D1
Note that D2 is twice R2, and similar for D1. It was assumed correlation between the three
variables was minimal. Fitting linear trend lines to these data is a gross approximation; however,
23
the trends are consistent and believable and given the time frame of this project, many
simplifications are necessary.
The three trend lines resulting from the above three plots give tip angle as a function of Hc, R1,
and R2. For example:
φ Hc = tan −1 (m Hc H c + bHc )
The first objective function, Performance (cup holding), is then calculated as:
Pc = −(φ Hc + φ R1 + φ R 2 )
The next objective function, Performance (ease of use), minimizes the complexity of the design
and maximizes finger clearance. This can be stated as:
Pe = -# parts - # incorrect uses + block separation
In terms of the model variables and parameters,
Pe = -Np – Ni + s
The Ergonomics objective function attempts to minimize the pull force necessary to remove the
bottom plate, as well as maximize the outside radius to avoid hands getting wedged:
E = -Fpull + R1
Versatility is a sum of the total unit depth and the total unit diameter. Minimizing this will
increase the ability to fit the Driver’s Dream in a multitude of vehicle platforms.
V = –true depth – (outer diameter + wall thickness)
Or,
V = –Ht – (R2+Tw)
Finally, Craftsmanship looks at gaps formed between the blocks and the removable bottom:
C = –#gaps – gap size – gap variation
In terms of model variables,
C = –Ng – gs – gv
Having defined all five objective functions, a basic monotonicity analysis demonstrates
relationships between model variables and each objective. The following table also lists relevant
dependent variables:
24
Table 5: Monotonicity
1 Outer Radius
R2
2 Inner Radius
R1
3 Height Cup holder
Hc
4 Length of outside of block
b
5 Length of inside of block
a
6 removable bottom inner radius
Rb1
7 removable bottom Outer radius
Rb2
8 Removable Bottom arc length of opening
Lb
circumferential distance between blocks
s
tab pull force
Fpull
number of gaps
Ng
gap size
gs
gap variation
gv
Height of Total Device
Ht
Pc (+)
Pe (+)
+
+
+
E (+)
Vr (+)
Cr (+)
+
+
-
+
+
-
+
+
-
-
-
Each of these objective functions was modified slightly to give values roughly within a range of
10. The model objective function is then a weighted sum as follows:
f = 10Pc + 5Pe + E + V + C
The reasoning behind these weights are to emphasize the true purpose of the cup holder in that it
serves to hold beverage containers, to increase the importance of ease of use, and to give equal
consideration to ergonomics, versatility, and craftsmanship. Certainly these weights and this
objective strategy is subjective and somewhat arbitrary. These weights could be tuned in further
studies to reflect marketability, or upscale target audience, for example. The objective function
is summarized here:
Table 6: Objective Function Summary
OBJECTIVE
max engineering performance
Perf(cupholding)
Perf(easeofuse)
Erg
Vers
Craft
Pc+Pe+E+V+C
-(phi_Hc+phi_R1+phi_R2)
-Np-Ni+s
-Fpull+R1
-Ht-(R2+Tw)
-Ng-gs-gv
To find the optimal values for the eight variables, the model was optimized in Excel using the
built-in Solver tool. A summary of results is given in the following table:
Table 7: Optimized Design Values
25
Engineering Optimized Design
R2
R1
Hc
b
a
Rb1
Rb2
Lb
1.975
1.375
4
0.875
0.75
1.375
1.81
0.875
Full details of constraint activity and variable sensitivity are shown in Appendix G. At
optimality the solution is bounded by:
•
•
•
•
•
•
minimum radius of a pop can
maximum half-height of a Nalgene bottle
minimum clearance for fingers
block trapezoidal requirement
small change requirement
block/removable bottom interface
Sensitivity analysis shows an overwhelming dependence on the minimum inner radius as
constrained by the pop can radius. This is due in part to the tip angle analysis in cupholding
performance, although decreasing R1 would destroy the functionality of the cupholder.
So far the cup holder height has been relatively unconstrained. In the next sections the impact of
Hc on profit and cost will better characterize this important variable.
4. Economic Analysis
The first step in the economic modeling was to determine a market size. Because cup holders
represent at least a small portion of the cockpit in every vehicle, the target market was narrowed
to vehicles with a center console contiguous with the dashboard, yet large enough to
accommodate a design of this volume. Thus the midsize car segment was chosen, with 2003
sales as a continuous measure of demand. In actuality the demand would be discretized into
specific models by manufacturer: for more discussion on this topic, refer to the business plan in
Appendix J. Segment sales were taken from [6] and are shown in the table below:
Table 8: Midsize Car Sales Figures (2003)
MIDSIZE
Camry
Accord
Taurus
Impala
Altima
Grand Am
Malibu
Sebring
413000
397000
300000
267000
201000
156000
122000
100109
26
Postulating a maximum acceptable price of $15 per cup holder, the following graph illustrates
the simple tradeoff between price and demand:
Figure 18: Cost Function
Cost Function
2000000
1750000
1500000
y = -97805x + 1956109
Demand
1250000
1000000
750000
500000
250000
0
0
5
10
15
20
Price per cupholder ($)
In this preliminary analysis, optimal profit would be obtained by maximizing revenue. Using
revenue = price x demand, the following revenue curve is obtained:
Figure 19: Revenue Curve
27
Revenue
10000000
9000000
8000000
Revenue ($)
7000000
6000000
5000000
4000000
3000000
2000000
1000000
0
0
5
10
15
20
Price per cupholder ($)
Here it can be seen the optimal price is $10.00 for maximum revenue. This value will only be
used as a base design price, for comparison with optimization results. In actuality the profit is a
function of Demand, Price, and Cost:
∏ = P (Q) − C
The profit equation can be expanded further to show dependency on the price and design
variables. This is stated as:
~T
∏ = P(θ − λ P P + λ d ∆α~ ) − C
where Π is profit, P is price, θ is total market potential, λP is price elasticity, λd is a vector of
design characteristic elasticities, α is a vector of design variables, and C is cost. With a cup
holder it is very difficult to directly translate design variables into product characteristics that
effect how the user perceives the product and how inexpensive the product is to manufacture.
For this analysis the cupholder height, Hc, will be used in both the function for Demand and the
function for Cost to represent an elementary tradeoff between design functionality and cost.
Looking first at revenue as a function of P and Hc, the total market potential and price elasticity
have already been estimated from the Cost Function in Figure 18 above. Thus:
θ = 1,956,109
λP = 97,805
Cup holder height can be related to demand by assuming a greater height accommodates a larger
range of containers, and will therefore translate into increased market share and customer
satisfaction. Assuming cup holder depths are normally distributed about a value roughly half the
height of the pop can, maximum market share multiplied by the cumulative function gives the
total sales. The design variable of cup holder height was used as operating variable, and for the
normal distribution a mean of 2” and a standard deviation of 1” was assumed. For example, the
28
Driver’s Dream design with height equal to two inches would capture 50% of the market. These
numbers were based on a very quick approximation of standard cup holder depths as measured
during the benchmarking process. A better elasticity value will be determined in the Market
Analysis section (pg 30). Therefore, the demand function in this section will be called the
Microeconomic Demand Function, Qe:
Qe = 1,956,109 − 97,805P − 1,956,109(1 − normdist ( H c ))
Costs for the cupholder can be divided into fixed operating costs and variable material and wage
costs
C = Cf + Cv
Fixed cost is composed of sales expenses and equipment upkeep, as detailed in the business plan
in Appendix J. One-time investment costs are ignored here and examined in the business plan as
well. Fixed cost per year can be summarized as:
Cf = $139,000
Variable cost is a sum of wage cost and material cost:
Cv = Cw + Cm
Calculations for material cost per part and for total payroll cost per hour are given in Table 9
below:
Table 9: Cost Analysis
Cost Analysis
material volume (cm^3)
material density ABS (g/cm^3)
ABS Cost ($/lb)
CupHolder Material Cost With ABS
spring cost per holder ($)
Number of Components Manufactured
Number of Lines Needed for Each Component
Number of Line Workers Per Component Line
Number of Assembly Lines Needed
Number of Workers per Assembly Line
Number of Workers Needed to Transport Material
Estimated number of line and transport workers
average wage line and transport worker $/hr
average number of supervisors
average wage line supervisor $/hr
average molding time per part (sec)
183.88
1.025
0.79
0.31
0.10
4
1
2
1
5
2
15
13.00
1
26.00
90
29
In the above calculations, wage cost is assumed a function of Hc. Cup holder height can be
related to assembly difficulty, and thus the number of workers required to assemble the device.
Therefore the number of workers on the assembly line scales from 2 to 5 relative to Hc.
Inputting demand into the model produces first the material cost:
Cm = $0.41(Q)
Research into manufacturing methods led to the determination that the injection-molding process
would be the bottleneck of the Driver’s Dream production. Therefore, man-hours required are
found by dividing demand by average molding time per part as given in Table 9 above. Cw can
now be rewritten as:
Cw =
Q
(Wl + Ws )
160
where Wl is line worker wage and Ws is supervisor wage. Assuming there is one supervisor
necessary, Wl and Ws are calculated:
Wl = $13(11 + H c ))
Wl = $26(1)
To restate briefly, Cost is given by:
C = Cf + Cm + Cw
With the groundwork laid for interdependencies between Price, Demand, and Cost, the next step
is to re-optimize the Driver’s Dream Cup Holder to maximize profit. With the additional
variable of price added since the construction of the engineering optimization model, two new
constraints are added to provide reasonable upper and lower bounds:
P >= $5
P <= $15
Furthermore, the model was simplified to speed calculations and shift focus to the relevant
variables. For this analysis the height of the block, Hb, was assumed equal to the sum of the cup
holder height, Hc, and the removable bottom thickness, tb:
Hb = Hc + tb
Then total cup holder height, Ht, was set to the sum of Hb and Hc:
Ht = Hb + Hc
Results of the optimization are shown in Table 10 below:
30
Table 10: Economic Model Results
profit
revenue
cost
price
#blocks
rem. bottom
height
demand
our design
(Hc=4",P=$10)
$
7,524,336
$
9,335,570
$
1,811,234
$10.00
3
1
4.00
933,557
optimal for profit
$
$
$
7,568,004
9,262,175
1,694,170
$10.67
3
1
4.00
868,204
For comparison they are presented next to the Cost, Revenue, and Profit figures resulting from
the design given by the Engineering Analysis. Constraint activity is identical to that for the
Engineering Model. Changes from the engineering-optimized design are minor, only a slight
increase in price per unit. However, this result was predictable: the model of demand using a
normal distribution forces assignment of parameters to define the distribution. Without market
data the chosen values conveniently cause the optimization results to roughly agree with the old
design.
A more in-depth study of market forces and another look at the relevant design variables will be
covered in the next section.
5. Marketing Analysis
Given the previous exploration of the economic fundamentals in the context of Driver’s Dream
design, a more analytical and meaningful relationship between design characteristics and
customer demand is needed. Assuming the target market is still midsize autos as detailed in the
previous section – except that now a more realistic goal of 50% of the market is set – what
elements of the design and price are most important to the customer and what values will
maximize customer satisfaction (and thus profits)? Clearly the cup holder height, Hc, is a critical
design variable. However, in this section two more characteristics, as well as price, will be
evaluated to gage marketability.
The first characteristic is number of blocks, or Nb. Our nominal design assumes three blocks
based on flexibility in adapting to various container sizes. To determine if customers are willing
to pay for more or would prefer less, Nb was opened to discrete values of 0, 2, 3, and 4. The
second characteristic is the removable bottom. This will become a binary variable, i.e. a
removable bottom is either present (1) or not (0). Obviously both these characteristics are not
specifically design variables as defined in the Engineering Analysis, as both are inherently
discrete. Yet they capture important aspects of the cup holder functionality and using Discrete
Choice Analysis it will be shown they can be quantitatively linked to product demand.
The first step in our DCA study was to conduct a survey of classmates. For this, levels for each
of the aforementioned characteristics, as well as price, were determined and are shown in Table
11 below:
31
Table 11: Characteristic Levels
symbol
p
z1
z2
z3
w=1
w=2
$5
$10
0 blocks
2 blocks
w/o bottom w/bottom
Hc=2"
Hc=3"
w=3
$15
3 blocks
w=4
4 blocks
Hc=4"
where z1 is # blocks, z2 is removable bottom, and z3 is cup holder height.
A partial-factorial question structure was designed using SAS software, and the survey was
administered to roughly 36 respondents. The survey can be found in Appendix H. Using the
Logit Model, part-worths for the characteristic levels, and a no-choice option, were calculated
and are summarized in the following table:
Table 12: Part Worths
p
z1
z2
z3
NC
w=1
0
0
0
0
w=2
w=3
w=4
-0.654017 -1.403981
1.455087 2.155793 2.210517
1.199142
0.731445 0.430609
1.718538
These part-worths give utility at the discrete characteristic levels. With the goal of eventually
returning to optimization in Solver, spline interpolation was used to approximate product utility
as a continuous function of characteristic value. A sample calculation of product demand based
on given characteristic values is shown below:
Table 13: Demand Sample Calculation
value
p
$12.00
z1
3
z2
1
z3
2.8
total utility of new product
utility of no choice
utility
-0.94
2.16
1.20
0.67
3.08
1.72
Pr(our product)
Pr(no choice)
79.60%
20.40%
market size 1956109
monopoly demand 1,557,116
50% of market 778,558
This method can be iterated to find design elasticities for each of the characteristics. The
following graphs represent these elasticities, with trend lines fit:
32
Figure 20: Product Characteristic Elasticities
lam bda_z1
lam bda_P
900
900
800
800
700
700
y = -22093x + 995520
600
600
500
500
400
400
300
300
$5
$7
$9
$11
$13
$15
y = 11929x 3 - 174930x 2 + 785421x - 315514
10
2
lam bda_z2
4
lam bda_z3
900
900
800
800
y = -79634x 2 + 512314x + 9924.8
700
700
y = 245470x + 541117
600
600
500
500
400
400
300
3
300
0
non-removable
removable
1
2.00
2.50
3.00
3.50
4.00
Comparing first the price elasticity to that estimated in the Economic Analysis, it can be seen
here that demand drops more than four times less rapidly with price. On the one hand, it is
possible the survey did not fully explain the consequences of price considering the number of
units produced. On the other hand, the original price elasticity was calculated using somewhat
artificial price boundaries.
The demand elasticity for Hc is shown to be vastly different from the cumulative normal
distribution function employed in the Economic Analysis. Here demand peaks near 3.2”, and
has less variability across the range of cup holder heights.
Demand elasticity for number of blocks was modeled as a complex polynomial, but the
important trend is that four and three blocks lend roughly equal demand, with an almost linear
drop-off below. Also, a removable bottom is clearly demonstrated as a customer-preferred
characteristic.
To re-optimize the design for profit, the demand is tied to product characteristics via utility as in
the calculations above (Table 13 & Figure 20). Returning to the elementary profit equation:
∏ = P (Q) − C
33
Qm, the Marketing Demand Function, is now a function of P, z1, z2, and z3, and cost is a function
of z3 as before. Yet the new model cannot be directly input into Solver since z1 and z2 are
inherently discrete. Instead of enumerating all cases by complex parametric study, the design
space can be limited by examining the elasticities. First, a removable bottom yields an obvious
advantage over a non-removable bottom, so all cases where z1=0 can be eliminated. Second, a
cup holder with zero or two blocks is far less preferable than one with three or four, so the
possibilities are again cut in half. What remains are two parametric studies:
•
•
•
•
z1 = 1
z2 = 3 or 4
z3 is variable
price is variable
This is in a form that can be handled by Solver. Results of the two cases are presented below:
Table 14: Marketing Parametric Study Results
profit
revenue
cost
price
#blocks
rem. bottom
height
demand
parametric study 1
(#blocks = 3)
$
6,317,896
$
7,865,870
$
1,547,974
$10.00
3
1
4.00
786,587
optimal for profit
(#blocks = 3)
$
9,317,002
$
10,685,100
$
1,368,098
$15.00
3
1
3.19
712,340
parametric study 2
(#blocks = 4)
$
6,385,914
$
7,948,730
$
1,562,816
$10.00
4
1
4.00
794,873
optimal for profit
(#blocks = 4)
$
9,455,814
$
10,841,955
$
1,386,141
$15.00
4
1
3.19
722,797
In both cases the optimization algorithm finds a greatly improved design, albeit through
maximizing the price and setting Hc to the value representing the peak of the design elasticity
curve in Figure 20 above. On the surface, a four-block design seems to have an advantage as it
produces approximately $140,000 more profit. However, this highlights a limitation of the
model: the relatively simple cost model does not account for expense derived by adding blocks.
This increase in complexity without penalty is probably unrealistic, and further analysis would
need to account for such tradeoffs.
A final comparison of all design iterations and the resulting changes in profit, etc. can be found
in Appendix I.
6. Additional Design Consideration
6.1 Impact of Product
The design of the Drivers Dream Cup Holder is intended to have a positive impact on all that it
affects. Throughout the design process we kept in mind the environmental and human
interaction effects our product would have. There has become a growing concern for the future
of our natural resources. Also the society within which we manufacture our product will be
34
impacted. It has been estimated up to 80% of the environmental impact of a product is
determined during the design stage [4]. As designers we must take into account these issues
when choosing materials for our product, determining the ease of assembly and disassembly, the
ability to recycle the product after use, and consumer safety during use of the product.
We have chosen to use ABS as the material of which to manufacture our cup holder. Since we
are purely composing the cup holder out of ABS it can easily be reused for other purposes. The
recycle ability of ABS is growing based on a study: Composition, Properties and Economic
Study of Recycled Refrigerators, from PlasticsResource.com information on plastics and the
environment. The data they collected clearly indicate that the value of recovered plastics,
particularly ABS, will increase [5]. Thus, we are confident that the use of this material will be
effective in terms of our responsibilities to consumers, society and the environment.
Another aspect of environmental impact is the ease of disassembling the cup holder for
recycling. The design of the cup holder was created with ease of assembly and disassembly in
mind. We designed the snap on top for ease of removal from the center consol and easy access
to the inside mechanics of the cup holder. This is for the purpose of fixing and more importantly
for the disassembly of the product at the end of its life time for recycling. To ensure that the cup
holder is easy to disassemble for recycling we have also minimized the materials used. This is
important to mention again since with only one material, minus the springs, the cup holder does
not need to be completely broken apart. We have successfully created a product that can be
easily recycled, yet is still functional.
Another environmental issue is to design the manufacturing process to be as safe as possible.
This includes materials that are environmentally friendly, as previously mentioned. This will
prevent spills and leaks of various toxic chemicals and will prevent harmful fumes. Also the
manufacturing design includes minimal emissions and utility use; thus minimizing air and water
pollution. Also, in designing the manufacturing process, waste and scrap materials should be
prevented as much as possible. Through the process of injection molding we have prevented the
possibility of scraps that can ultimately have an adverse effect on the environment.
The design must also be tailored to the needs of the consumer and the capacities of the
manufacturer. These human interactions with the cup holder are based on the manufacturability,
and usability of the product. The society of the area within which the cup holder is being
manufactured will also be impacted due to an increase of jobs. The manufacturing process we
have designed includes 16 workers paid a substantial wage in proper working conditions
provided by Johnson Controls Inc. The human interaction during the manufacturing process
should be a positive experience given that the cup holder is fairly easy to assemble.
The use of cup holders while driving has been the cause of many accidents in the United States.
We hope to decrease this concern with an automatically adjustable cup holder large enough for a
Nalgene bottle. The consumer using the cup holder will find it easy to operate and thus have a
lower potential to cause accidents while using it. In effect we will decrease the number of
negative human interactions and generate safer driving circumstances.
35
We have designed out cup holder to produce a positive impact on both the environment and
human interactions, to the best of our knowledge. Ultimately, our design reflects good judgment
and values that we maintain as citizens of this society.
6.2 Ergonomics
In designing the Driver’s Dream cup holder anthropometric data was used to determine some of
the dimensions. The size of a 95th percentile male’s fist was taken into account so that a man
could place their whole fist in the cup holder when the buttons are depressed. This will aid in
cleaning. It was also important that fingertips would fit between a soda can and the side walls of
the cup holder, this helped determine the width of the buttons. Some other measurements that
took ergonomics into account were the cup holders total height, so that the bottom could be
reached by as many people as possible. Also the finger grips for the removable bottom need to
be large enough for a male to pull it out. A person also must be able to create the grip force
between a finger and the thumb to pull out the bottom.
7. Final Design Recommendations
The Final design of the Drivers Dream Cup Holder has accomplished our original goal. We set
out to design an adjustable cup holder that accommodates a variety of sized cups ranging from a
Nalgene water bottle to a pop can. We also designed our cup holder to be easily manufactured,
easy to use, and easy to maintain and clean, as well as versatile among various vehicles. We also
anticipate that our cup holder will be applicable for multiple uses such as a change tray or a cell
phone holder. The design of our cup holder is also safe for all sized hands and fingers as well as
durable to withstand the downward forces of constant usage. We have accomplished all of these
specifications within our single design.
Our final design has three push down blocks, a removable bottom for easy cleaning, and a height
of 3.2 inches. These have been determined through engineering, marketing, and economic
analyses. We conducted a survey for the marketing analysis and found that among the people
surveyed they preferred a low cost product with three support blocks, a removable bottom, and at
least a 3.2 inch depth of the cup holder. However, we failed to include a brief description of our
prototype, we assumed that our audience had a good idea of what we were interested in from
visually seeing our prototype. People may have assumed that they were buying this cup holder
for themselves, while in fact we would have liked them to take the perspective of a car
manufacturer buying a large quantity of cup holders. Overall, the surveyed audience prefered the
low cost but not as strongly as the economic analysis showed. These helped to support our
decision on specific dimensions and critical aspects of our cup holder.
The material we recommend for manufacturing our cup holder is Acrylonitrile Butadiene Styrene
(ABS). We chose this material because it is the material most often used to produce the center
console area where our cup holder would be placed. We initially set out to achieve better
craftsmanship of cup holders and found it difficult to demonstrate in our prototypes given limited
resources. A good prototype would have accelerated the craftsmanship analysis of the cup
holder. However, we intend the actual finished design to be more precise and of better quality
due to the manufacturing process of injection molding and the use of a single material, ABS.
36
8. Conclusion
During the initial stages of our project we completed a survey on the typical cup holders that are
available in today’s marketplace, and it became apparent that cup holders appear to be an
afterthought to automotive design. Cup holders appear to be one of the last items designed into
the console. This was very interesting because everyone we spoke to had a relatively strong
opinion on the quality of their car’s cup holder, many people had gripes about their designs.
This was interesting because it seemed that the car manufacturers were missing out on a key
statement from consumers. If a manufacturer had the ability to put an affordable cup holder in
their car that performed better than that of their competitors it seemed that they would be able to
market it very well as an additional component of interior quality. We treated the size constraint
as an absolute but we were determined that we could produce what consumers were looking for
by designing a cup holder characterized by its ability to conform to a variety of cup sizes while
acting as a multi-functional storage area.
The initial steps in actually designing our concept were difficult because we had to create a
functional prototype that had a design suitable for mass production. In previous design courses
the members of our group had not been required to design for a mass production market. We
were previously free to design and build with the intent of only creating one and only one final
piece. This caused difficulties because we had a couple designs we felt might hold cups better
than our final design, but they would be either too difficult to manufacture, or would not last
very long in day to day use. Because of this we ended up choosing one of our most simple
designs as the final product. Although the final design was simple it still had to be revised
several times on paper before it was ready to undergo prototyping. If there weren’t time
constraints on this project our group would still be trying to perfect the design on paper. We
learned that perfection is pretty unrealistic and that utilizing programs such as Adams and
Unigraphics is key to keeping the design process in steady progression.
Another issue encountered initially in our design process was defining the qualities of
craftsmanship that pertain to a cup holder. When trying to define craftsmanship we often found
ourselves listing traits associated more with functionality of the device. After we eventually
decided upon some of the basic principals that define craftsmanship, it became difficult to design
around them. When designing we attempted to create something that would look sharp, feel
solid, and functional well at the same time. Because it is difficult to actually measure the
qualitative traits of feeling and seeing a concept in its working environment when designing it,
we had to settle on the fact that if we created a design that fulfilled our functionality
requirements with tight production tolerances, it would be perceived as having good
craftsmanship.
Although we do have what we feel to be a great design, one area of concern is the ability to
capture the market with the ferocity that we have predicted in our business plan. To ensure that
we would be able to take the sector of the cup holding market that we desire to, it is key that we
do more user surveys on our project. Several short term use analysis surveys on our product
from consumers would be very helpful in getting initial thoughts and reactions to the adequacy
of our design. A handful of products could also be given out to users so that we may get some
feedback on problems that one may encounter when using the holder on a daily basis. Any
37
suggestions or positive reactions received could be used to further improve our design, making it
more marketable to all of the car companies.
The opportunity to design and create an engineering and business plan for a practical device was
a great learning experience for everyone the Driver’s Dream Team. Although all of our team
members had some experience in the subjects emphasized by the business and marketing portion
of the course, none of us had ever really had the opportunity to use the knowledge in
collaboration with our engineering back round. Three of our group members had previously
participated in summer engineering internships where we were able to view the real world
interaction between engineering and marketing/business portions of a company. Coming into the
project it was fair to say that the three of us had an inclination towards feeling that the
marketing/business portion of the companies we worked at had a tendency to push numbers,
deadlines, and suggestions into the engineering portion of the company without understanding or
caring about the affect that it would have on the engineering process for the product being
created. Although some conflicting priorities between these two sectors will never be resolved
completely the knowledge gained from seeing a marketing perspective on a product analysis
gave us a better idea of where their requests were coming from.
References
[1]United States Patent and Trademark Office, 8 Oct. 2004 <http://www.uspto.gov>.
[2]“Food Portion Sizes Growing with Our Waistlines”, Colorado Department of Public Health
and Environment, 5 Oct 2004 <http://www.cdphe.state.co.us/steps/portiongrowth.html>.
[3]Honda Website, 10 Oct 2004, <http://www.honda.com.>
[4]“Directive of the European Parliament and of the council on establishing a framework for the
setting of Eco-design requirements for Energy-Using Products and amending Council Directive”
92/42/EEC, Brussels, January 8, 2003. 453 final 2003/0172, <http://europa.eu.int/eurlex/en/com/pdf/2003/com2003_0453en01.pdf>
[5]“Composition, Properties and Economic Study of Recycled Refrigerators,” December 11,
2004,
http://www.plasticsresource.com/s_plasticsresource/doc.asp?TRACKID=&CID=174&DID=381
[6]“IN DEPTH: BEST SELLING AUTOMOBILES”, Business First, April 12, 2004,
<http://buffalo.bizjournals.com/buffalo/stories/2004/04/12/focus2.html?page=2>
38
Appendix A: Information Gathering
Some comments gathered from friends and family:
“ The cupholder pulls out, which I like. On the other hand, it pulls out
right on top of the only place to hold things in the whole front of the car,
the place I put coins, sunglasses, a cassette. All of that has to be moved
to pull it out, except coins, which are skinny.
“
It has fixed size circles. I would like for it to handle water bottles of
assorted diameters and fast food cups, even more diameters. I think I have
seen some with springy insides that adjust.
“
The pull out thing is fairly close to the tray below, so tall things are top
heavy and too easy to knock over.
“
I've seen some cupholders that are fairly think plastic and not well braced,
so that I've wondered what would happen if you had a relatively heavy and/or
full container in there and bounced over something.
“ While taking one of my elderly riders to the Dr a couple of weeks ago, I
discovered that her water bottle wouldn't fit into the cup holder. She
had to hold it the whole way into town and back. A cup holder made of
some sort of elastic material that could accommodate that various types
of soda and water bottles would be nice.
“
The current Passat design is acceptable. Two cupholders with small clips
that adjust to a reasonable variation in different cup sizes. But they take up
valuable space in the center where I need to access and store some of the
following:
1. Sun glass clips. I put these on and off all the time. They are fragile
and I need a ready place to store them when not driving or driving in
low light or night conditions.
2. Cell phone cradle. I'd like to keep it off the seat and off the floor,
and I use an earbud while driving. Not practical to keep it in my
pocket (if I have one) or on the passenger seat (especially if there
is a passenger).
3. GPS used for navigation.
39
Appendix B: QFD Chart
+
+
++
++
Ergonomic correctness
Versitility across vehicles
Usability for non-drinks
Easy to maintain, clean
Low cost
Safety of hands, fingers
Durability/breakability
7
6
6
7
9
9
3
3
3
9
5
4
6
1
1
1
9
9
3
9
3
1
3
3
1
1
3
1
9
Spring Post Height (+)
Spring Post Thickness (-)
True Bottom Curvature (+)
9
5
3
2
1
5
2
5
5
2
4
3
4
2
4
5
3
2
3
1
4
5
5
5
4
3
1
2
2
5
5
1
2
3
2
3
5
4
5
3
4
3
3
Spring Tension (+)
Pull-out cupholder
Manufacturability
9
Honda cupholder
High quality and craftsmanship
9
Our Proposed Design
Ease of use
+
+
Pull Tab Size (+)
1
++
Removeable Bottom Thickness (+)
9
3
--
Removeable Bottom Diameter (+)
9
3
-
Spring Diameter (+)
Block Height (-)
Not interfere with vehicle operation
Block Width (+)
Depth of Base Hole (+)
9
10
8
W eight
Accommodate cup size range
Diameter of Base Hole (+)
-
Number of Blocks (+)
+
Block Wall Thickness (+)
+
9
3
9
3
3
1
3
1
1
1
9
1
9
3
3
1
9
9
3
1
Measurement Unit mm
mm
mm
mm
9
1
3
3
mm
#
mm
3
mm
mm mm3 mm
9
9
9
1
mm
mm
N
Base Value 0.00 0.00 9.00 0.00 0.00 1.00 0.00 0.00 0.00 0.00 0.00 4.00 0.00 0.00
Importance Rating
Total 214
214
158
163
120
141
93
66
43
51
15
115
115
163
Normalized 0.20 0.20 0.15 0.15 0.11 0.13 0.09 0.06 0.04 0.05 0.01 0.11 0.11 0.15
40
Appendix C: Gantt Charts
October Gnatt Chart
October
1 2 3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Measurements of Car
Junk Yard
Choose Cars
Generate Concepts
Talk to people
Research previous Designs
Finish Defining Need
Design Objectives (QFD)
Design Criteria
Patent Search
Develop a few Ideas
Ergonomic Concerns
Choose Final Idea
Layout Design Process
Develop Final Idea
First CAD Drawings
First Prototype
Proposal
Presentation
Ergonomic Analysis
Stress-Strain
Materials
Dynamics Analysis
Craftsmanship Analysis
Optimization Modeling
Marcy Gone
NOVEMBER Gnatt Chart
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
1
2
3
4
5
6
7
8
9 10 11 12 13
Ergonomic Analysis
Stress-Strain
Materials
Dynamics Analysis
Craftsmanship Analysis
Optimization Modeling
2nd Prototype
Progress/ Design Review
Manufactuing Analysis
Cost Analysis
Surveys
Thanksgiving Break
DECEMBER Gnatt Chart
Expo Prototype
Bus. Plant Report
Bus. Plan Presentation
Final Paper
Team
Marcy
Sophia
Steve
Nick
Due Date
41
Appendix D: Pugh Chart
3
Tapered
Block
center
Spring Circles Elastic pieces Gears Fold down
Design Criteria
Weight
Sketches
Design Design Design Design Design Design #6
#1
#2
#3
#4
#5
Durability
2
+
+
-
-
-
--
Cost
2
+
0
++
+
-
++
Ease of Manufacturing
2
+
-
+
+
--
+
Universality
2
+
+
0
0
0
++
Safety
1
++
0
++
+
++
+
Adjustability
1
++
+
-
0
+
+
Required User
Interaction
Novelty of Design
1
+
0
+
+
+
0
1
+
++
+
0
++
--
Cleaning Capability
2
-
0
+
-
0
0
Versatility
1
-
-
+
0
0
+
Reliability
2
0
0
+
-
+
+
Cup Hugging Ability
2
+
0
-
0
++
+
Quality Feel
2
+
+
--
0
++
--
18
10
13
7
16
17
2
10
1
6
3
3
3
3
9
6
8
10
15
7
4
1
8
7
+
0
Total Points
42
Appendix E: Design Flowchart
Appendix F: Technical Analysis
Diameter of a soda can = 2.5 inches
Diameter of a Nalgene = 3.5 inches
Inside radius R1 = 2.5 inches
Outside radius R2 = 3.5 inches
Block thickness bt = 0.5 inches
Height of a Nalgene = 8 inches
Height of a soda can = 4.75 inches
Outer cup holder height = 2.375”< Hc< 4”
Average block height Hb = 3.1875 inches
Pinch length/thickness of removable bottom tab = 2mm<L<1cm
Total height of cup holder = 2 * Outer cup holder height =Ht = 3 inches
ABS Tensile Strength = 40-50 MPa
Hc
R1
R2
Ht
L
bt
Hb
Appendix G: Engineering Model Results
Target Cell (Max)
Cell
Name
$C$3
Pc+Pe+E+V+C
Original Value Final Value
-140.2
-140.2
Adjustable Cells
Cell
Name
$C$25 R_2
$C$26 R_1
$C$27 H_c
$C$28 b value
$C$29 a value
$C$30 Rb1 value
$C$31 Rb2 value
$C$32 Lb value
Original Value Final Value
1.975
1.975
1.375
1.375
4
4
0.875
0.875
0.75
0.75
1.38
1.38
1.81
1.81
0.88
0.88
Constraints
Cell
Name
$C$90 Rnalgene+(1/8)-R2<0 value
$C$91 Rpop+(1/8)-R1<0 value
$C$92 Tf-(R2-R1)<=0 value
$C$93 a-b+(1/8)<0 value
$C$94 a-C1/3<0 value
$C$95 Dd-a<=0 value
$C$96 sigma-sigma_yield<=0 value
$C$97 Fpull-Fmax_tab<=0 value
$C$98 R1-R2<=0 value
$C$99 -R1<=0 value
$C$100 -Hb<=0 value
$C$101 Hc-Hnalgene/2<=0 value
$C$102 -a<=0 value
$C$103 0.25-b<=0 value
$C$104 Rb1-R1<=0 value
$C$105 0.5-Rb1<=0 value
$C$106 R1-Rb2<=0 value
$C$107 Rb2-R2<=0 value
$C$108 b-Lb<=0 value
$C$109 -s<=0 value
$C$110 R2-2.25<=0 value
Cell Value
-0.1
0
0
0
-2.13
0
-4342
-8.16
-0.6
-1.375
-4.25
0
-0.75
-0.625
0.00
-0.88
-0.44
-0.17
0.00
-3.24
-0.275
Formula
$C$90<=0
$C$91<=0
$C$92<=0
$C$93<=0
$C$94<=0
$C$95<=0
$C$96<=0
$C$97<=0
$C$98<=0
$C$99<=0
$C$100<=0
$C$101<=0
$C$102<=0
$C$103<=0
$C$104<=0
$C$105<=0
$C$106<=0
$C$107<=0
$C$108<=0
$C$109<=0
$C$110<=0
Status
Not Binding
Binding
Binding
Binding
Not Binding
Binding
Not Binding
Not Binding
Not Binding
Not Binding
Not Binding
Binding
Not Binding
Not Binding
Binding
Not Binding
Not Binding
Not Binding
Binding
Not Binding
Not Binding
Slack
0.1
0
0
0
2.129793266
0
4341.511936
8.16
0.6
1.375
4.25
0
0.75
0.625
0
0.875
0.435
0.165
0
3.237175
0.275
45
Adjustable Cells
Cell
$C$25
$C$26
$C$27
$C$28
$C$29
$C$30
$C$31
$C$32
Reduced
Gradient
R_2
R_1
H_c
b value
a value
Rb1 value
Rb2 value
Lb value
Final
Value
1.975
1.375
4
0.875
0.75
1.38
1.81
0.88
Name
Rnalgene+(1/8)-R2<0 value
Rpop+(1/8)-R1<0 value
Tf-(R2-R1)<=0 value
a-b+(1/8)<0 value
a-C1/3<0 value
Dd-a<=0 value
sigma-sigma_yield<=0 value
Fpull-Fmax_tab<=0 value
R1-R2<=0 value
-R1<=0 value
-Hb<=0 value
Hc-Hnalgene/2<=0 value
-a<=0 value
0.25-b<=0 value
Rb1-R1<=0 value
0.5-Rb1<=0 value
R1-Rb2<=0 value
Rb2-R2<=0 value
b-Lb<=0 value
-s<=0 value
R2-2.25<=0 value
Final
Value
-0.1
0
0
0
-2.13
0
-4342
-8.16
-0.6
-1.375
-4.25
0
-0.75
-0.625
0.00
-0.88
-0.44
-0.17
0.00
-3.24
-0.275
Lagrange
Multiplier
Name
0
0
0
0
0
0.00
0.00
0.00
Constraints
Cell
$C$90
$C$91
$C$92
$C$93
$C$94
$C$95
$C$96
$C$97
$C$98
$C$99
$C$100
$C$101
$C$102
$C$103
$C$104
$C$105
$C$106
$C$107
$C$108
$C$109
$C$110
0
98.43129349
55.78956604
30.83333302
0.00
31.66666639
0
0.00
0
0
0
17.67536736
0
0
-10.00
0.00
0.00
0.00
20.00
0.00
0
46
Appendix H: Survey
Driver’s Dream Cup Holder
Survey
Team #5
Nick Magnuski
Sophia Reyes
Steve Strine
Marcy Urbance
Directions: Each question pertains to the following design dimensions.
• Number of support blocks within the cup holder: 0, 2, 3, or 4 blocks
• Removable bottom or no removable bottom
• Cup holder height: 2”, 3”, or 4”
• Price: $5, $10, or $15
47
Block
Soda Can
Block
Height
Soda Can
Removable
bottom
handle
Removable
bottom
handle
Key
1.
A) two blocks, removable bottom, cup holder height =3”, price = $15
B) Zero blocks, no removable bottom, cup holder height =2”, price = $5
C) Four blocks, removable bottom, cup holder height = 4”, price = $10
48
D) No Choice
49
2.
A) Four blocks, no removable bottom, cup holder height = 2”, price = $5
B) Zero blocks, removable bottom, cup holder height = 4”, price = $10
C) Two blocks, no removable bottom, cup holder height = 3”, price = $15
D) No Choice
50
3.
A) Zero blocks, no removable bottom, cup holder height = 4”, price = $10
B) Three blocks, removable bottom, cup holder height = 2”, price = $15
C) Two blocks, removable bottom, cup holder height = 3”, price = $5
D) No Choice
51
4.
A) Four blocks, removable bottom, cup holder height = 4”, price = $10
B) Two blocks, no removable bottom, cup holder height = 2”, price = $5
C) Three blocks, no removable bottom, cup holder height = 3”, price = $15
D) No Choice
52
5.
A) Four blocks, no removable bottom, cup holder height = 2”, price = $15
B) Zero blocks, no removable bottom, cup holder height = 4”, price = $5
C) Two blocks, removable bottom, cup holder height = 3”, price = $10
D) No Choice
53
6.
A) Three blocks, removable bottom, cup holder height = 3”, price = $10
B) Four blocks, no removable bottom, cup holder height = 4”, price = $15
C) Zero blocks, removable bottom, cup holder height = 2”, price = $5
D) No Choice
54
7.
A) Two blocks, no removable bottom, cup holder height = 4”, price = $5
B) Zero blocks, removable bottom, cup holder height = 3”, price = $15
C) Three blocks, no removable bottom, cup holder height = 2”, price = $10
D) No Choice
55
8.
A) Four blocks, removable bottom, cup holder height = 4”, price = $10
B) Zero blocks, no removable bottom, cup holder height = 2”, price = $5
C) Three blocks, no removable bottom, cup holder height = 3”, price = $15
D) No Choice
56
9.
A) Zero blocks, no removable bottom, cup holder height = 4”, price = $10
B) Two blocks, removable bottom, cup holder height = 2”, price = $5
C) Four blocks, no removable bottom, cup holder height = 3”, price = $15
D) No Choice
57
10.
A) Two blocks, removable bottom, cup holder height = 3”, price = $10
B) Three blocks, no removable bottom, cup holder height = 4”, price = $5
C) Zero blocks, removable bottom, cup holder height = 2”, price = $15
D) No Choice
58
11.
A) Zero blocks, no removable bottom, cup holder height = 3”, price = $10
B) Three blocks, removable bottom, cup holder height = 4”, price = $5
C) Four blocks, removable bottom, cup holder height = 2”, price = $15
D) No Choice
59
12.
A) Four blocks, no removable bottom, cup holder height = 2”, price = $15
B) Three blocks, removable bottom, cup holder height = 4”, price = $10
C) Zero blocks, no removable bottom, cup holder height = 3”, price = $5
D) No Choice
60
13.
A) Zero blocks, no removable bottom, cup holder height = 3”, price = $10
B) Four blocks, no removable bottom, cup holder height = 4”, price = $5
C) Two blocks, removable bottom, cup holder height = 2”, price = $15
D) No Choice
61
14.
A) Zero blocks, removable bottom, cup holder height = 4”, price = $15
B) Two blocks, no removable bottom, cup holder height = 2”, price = $10
C) Three blocks, no removable bottom, cup holder height = 3”, price = $5
D) No Choice
62
15.
A) Three blocks, removable bottom, cup holder height = 4”, price = $10
B) Four blocks, no removable bottom, cup holder height = 3”, price = $5
C) Zero blocks, no removable bottom, cup holder height = 2”, price = $15
D) No Choice
63
16.
A) Three blocks, removable bottom, cup holder height = 2”, price = $10
B) Zero blocks, removable bottom, cup holder height = 3”, price = $15
C) Two blocks, no removable bottom, cup holder height = 4”, price = $5
D) No Choice
64
17.
A) Four blocks, removable bottom, cup holder height = 3”, price = $5
B) Three blocks, no removable bottom, cup holder height = 4”, price = $15
C) Two blocks, no removable bottom, cup holder height = 2”, price = $10
D) No Choice
65
18.
A) Four blocks, removable bottom, cup holder height = 3”, price = $5
B) Three blocks, no removable bottom, cup holder height = 2”, price = $10
C) Two blocks, removable bottom, cup holder height = 4”, price = $15
D) No Choice
66
19.
A) Four blocks, no removable bottom, cup holder height = 3”, price = $10
B) Three blocks, removable bottom, cup holder height = 2”, price = $15
C) Two blocks, removable bottom, cup holder height = 4”, price = $5
D) No Choice
67
20.
A) Four blocks, no removable bottom, cup holder height = 4”, price = $15
B) Zero blocks, removable bottom, cup holder height = 3”, price = $5
C) Two blocks, no removable bottom, cup holder height = 2”, price = $10
D) No Choice
68
21.
A) Four blocks, no removable bottom, cup holder height = 3”, price = $10
B) Three blocks, removable bottom, cup holder height = 2”, price = $5
C) Two blocks, removable bottom, cup holder height = 4”, price = $15
D) No Choice
69
22.
A) Two blocks, no removable bottom, cup holder height = 4”, price = $15
B) Four blocks, removable bottom, cup holder height = 2”, price = $10
C) Three blocks, removable bottom, cup holder height = 3”, price = $5
D) No Choice
70
23.
A) Four blocks, removable bottom, cup holder height = 2”, price = $5
B) Two blocks, no removable bottom, cup holder height = 3”, price = $10
C) Zero blocks, removable bottom, cup holder height = 4”, price = $15
D) No Choice
71
24.
A) Three blocks, no removable bottom, cup holder height = 4”, price = $15
B) Four blocks, removable bottom, cup holder height = 3”, price = $5
C) Zero blocks, removable bottom, cup holder height = 2”, price = $10
D) No Choice
72
Appendix I: Model Comparison
ENGINEERING
engineering
optimized
profit
revenue
cost
price
#blocks
rem. bottom
height
demand
n/a
n/a
n/a
n/a
3
1
4.00
n/a
ECONOMICS
our design
(Hc=4",P=$10)
$
7,524,336
$
9,335,570
$
1,811,234
$10.00
3
1
4.00
933,557
optimal for profit
$
$
$
7,568,004
9,262,175
1,694,170
$10.67
3
1
4.00
868,204
MARKETING
parametric study 1
(#blocks = 3)
$
6,317,896
$
7,865,870
$
1,547,974
$10.00
3
1
4.00
786,587
optimal for profit
(#blocks = 3)
$
9,317,002
$
10,685,100
$
1,368,098
$15.00
3
1
3.19
712,340
parametric study 2
(#blocks = 4)
$
6,385,914
$
7,948,730
$
1,562,816
$10.00
4
1
4.00
794,873
optimal for profit
(#blocks = 4)
$
9,455,814
$
10,841,955
$
1,386,141
$15.00
4
1
3.19
722,797
73
Appendix J: Business Plan
Business Opportunity
Objectives
The Driver’s Dream cup holder will be produced and manufactured by JCI or a comparable
company. The main objective is for this cup holder to become the cup holder of choice in
midsize vehicles. Over the next three years it is hoped that the Driver’s Dream cup holder will
be placed in 50% of all new midsize vehicles purchased. The product line will also be expanded
to produce a model that can be used in various other sized vehicles.
Product Description
The Driver’s Dream cup holder is an adjustable cup holder for the driver of a midsize vehicle. It
will automatically adjust to a variety of containers; while not being intrusive to the driver
controls or to the driver. The Driver’s Dream has the following advantages over an ordinary cup
holder:
• Ergonomic
• Easily adjustable to various container sizes
• Easy to use and clean
The Driver’s Dream line will be expanded to include various additions for different consumers.
The line will expand to include a cup holder that will fit in larger variety of cars. It will also be
expanded to include options for a larger variety of cup sizes if needed. A line will also be
included that incorporates a heating/cooling element to the cup holder. This will allow
beverages to be kept at a desired temperature.
Market Analysis
The market the Driver’s Dream is currently targeting is the owners of midsize cars; this market is
divided as shown in Figure 1.
Nissan
10%
Chrysler
5%
GM
29%
Honda
20%
Toyota
21%
Ford
15%
Figure 1: Market size of automakers in midsize vehicles
The type of driver of midsize cars that is being targeted are those drivers who spend a lot of time
driving in their car by themselves. The driver would want to accommodate many different types
of cups and water bottles.
74
Capital and Personal Resources
The new product line initial start-up costs are $1,050,000. This initial investment is to pay for
the costs of development, design, manufacturing engineering, manufacturing equipment, and
initial material costs. JCI will be able to fund this new project with revenues from other projects.
The production of the Driver’s Dream cup holder will be done at an existing JCI facility that has
extra floor space.
Financial Data
Capital Equipment and Suppy List
The Driver’s dream will require 3 injection molding machines and dies, assembly line
equipment, ABS plastic, and springs.
The cost of supplies per part is a total of $0.41. The cost of ABS per cup holder is $0.31 and the
springs cost $0.10.
Break-Even Analysis
The number of cup holders that need to be made to break-even is approximately 720,000 as
shown in Table 1 and Figure 2. This amount of cup holders will be produced before the end of
year one in order to keep up with demand.
Figure 2: Break-Even Analysis
$20,000,000.00
$15,000,000.00
$10,000,000.00
Break-even Point
$5,000,000.00
$0.00
-$5,000,000.00
-$10,000,000.00
0
500000
1000000
1500000
2000000
2500000
3000000
Number Produced
Table 1: Break-Even Analysis
Break-even Analysis
Break-even Amount
Assumptions:
Average Per-Unit Revenue
Average Per-Unit Variable
Cost
Total fixed costs 3 years
720,000
$10.00
$2.00
$5,965,200.00
75
Pro-forma Income and Cost
Table 2 shows the profit & loss statement for Driver’s Dream cup holder for the next three years.
Along with what the companies net present value is for the three years.
Table 2: Profit & Loss Statement 3 years
Year
Initial
Demand
Sales
Material costs of goods
Gross margin
Expenses:
Payroll
Sales and marketing
Depreciation
Equipment (Initial)
Equipment upkeep
Utilities
Total Op Costs
Profit before tax
TAX
Net profit
NPV
2005
2006
2007
712,000
$7,120,000.00
$356,000.00
$6,764,000.00
726,000
$7,260,000.00
$363,000.00
$6,897,000.00
741,000
$7,410,000.00
$370,500.00
$7,039,500.00
$1,444,200.00
$100,000.00
$8,000.00
$1,494,000.00
$100,000.00
$8,000.00
$1,555,000.00
$100,000.00
$8,000.00
$19,000.00
$12,000.00
$1,583,200.00
$5,180,800.00
$1,554,240.00
$3,626,560.00
$19,000.00
$14,000.00
$1,635,000.00
$5,262,000.00
$1,578,600.00
$3,683,400.00
$19,000.00
$15,000.00
$1,697,000.00
$5,342,500.00
$1,602,750.00
$3,739,750.00
$1,050,000.00
$1,050,000.00
($1,050,000.00)
$8,100,734.49
The assumptions made for calculating the cash flows for the next three years are shown in Table
3. It was also assumed that JCI or a similar company would have enough floor space for this
new project and that they also would be able to fund the initial investments for the project. The
discount rate was determined using the Capital asset pricing model, using a risk free rate (the rate
of a 15 yr bond) of 4.08%, a market rate of 10% and a Beta from JCI of 0.765.
Table 3: Rate Assumptions for Cash Flows
Tax Rate
30%
Discount Rate
8.61%
Rate of demand increase
2%
Supporting Documents
Patents
A patent search of United States Patents and Trademark website of patents granted after 1976.
The search was done by searching “cup holder.” The search presented 1411 items of which most
were not applicable; the applicable patents are shown in Table 4. A table of the applicable cup
holder patents is shown in Table 1 below. These cup holders did not have the range of
adjustability that is needed for car owners, especially those that are included as part of the center
counsel.
76
Table 4: Summary of “Cup Holder” Patent Search
Patent #
Description
D493,072
Adjustable cup holder
6,776,381
Cup holder
D497,779
Cup holder
6,799,705
Cup holder closure and release apparatus
6,796,591
Glove compartment and cup holder device for
automobile
6,732,894
Vehicle cup holder arm assembly
6,712,325
Cup holder for automobile
6,705,580
Cup holder for a motor vehicle
6,702,243
Cup holder for a vehicle
6,702,241
Cup holder
6,698,703
Compartment mounted automotive beverage
container holder
6,670,583
Heated cup holder system
6,644,526
Motor vehicle central console
6,637,709
Self-adjustable cup holders
6,637,617
Inflatable vehicle cup holder
5,573,214
Window Cup holder
Technical Analysis & Benchmarking
Technical analyses that were performed are shown in Appendix F.
Benchmarking was done by looking at existing cup holders in midsize vehicles and by making
various measurements of a Pontiac Grand Am to determine if the Driver’s Dream would fit into
the existing center console. These measurements were of the current cup holder area, this area
could be increased in order to fit the Driver’s Dream. The important measurements are shown in
Table 5.
Table 5: Grand Am Center Console Dimensions
Total Depth of Console
8.01 in
Length
6.59 in
Width
4.12 in
77