APD FALL 2010

ME 455 Final Report

Eco-Spin

Team 7Joseph Cha, Ryan Ollie, Kent Utama and Paul Von Hertsenberg

12/14/2010

Do you bike to work or school? Are you tired of forgetting to charge your cell phone overnight? Are you sick of your MP3 player dying due to low battery on your way to school? We’ve got you covered! Introducing Eco-Spin, your power on the go.

Eco-Spin is an affordable product that recycles the energy produced when biking. Eco-spin is easy to install and requires no further maintenance. Just grab the USB cable for your device, plug it into the port and you’re good to go.

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Table of ContentsNOMENCLATURE.........................................................................................................................................3

INTRODUCTION...........................................................................................................................................4

PREVIOUS DESIGNS.................................................................................................................................5

ENGINEEERING FUNCTIONALITY ANALYSIS...............................................................................................16

EMOTIONAL AND AESTHETIC ANALYSIS....................................................................................................17

MICROECONOMIC & MARKETING ANALYSIS.............................................................................................17

COST......................................................................................................................................................18

PROFIT OPTIMIZATION (ENGINEERING MODEL)....................................................................................20

PROFIT OPTIMIZATION (ENGINEERING AND MICROECONOMIC OBJECTIVE)........................................20

NET PRESENT VALUE & CASH FLOW......................................................................................................23

BREAKEVEN POINT................................................................................................................................24

MARKET EXPANSION & DEMAND PROJECTION.....................................................................................25

SUSTAINABILITY ANALYSIS.........................................................................................................................26

PRODUCT DEVELOPMENT PROCESS..........................................................................................................28

BROADER IMPACT.....................................................................................................................................29

CONCLUSION.............................................................................................................................................30

REFERENCES..............................................................................................................................................30

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NOMENCLATURE

Printed Circuit Board (PCB): A mechanical board that supports and connects electric components

Universal Serial Bus (USB): A common port for periphery devices, the Eco-Spin has USB compatibility which covers most phones and mp3 players, notably the iPod and iPhone. When a charge greater than 5 volts is sent to a USB device, it will be forced into charging mode.

Direct-Current (DC) Generator: A key component in our design, DC generators are the opposite of DC motors. Generators consist of an armature and a field winding. An armature (mechanical rotor) is the input, and as it spins, it creates electro-magnetic waves that is collected by the field coils and converted into electrical energy.

Net Present Value (NPV): The sum of Present Values, which represent the incoming and outgoing cash flows from the present, and also expected values in the future. Interest rates also factor into NPV calculations.

Design Optimization

E Power generated in an hour W ٠ hI Inertia lbm ٠ in2

α Angular acceleration rad/s2

dt Tire diameter inω Angular velocity rad/sdr Roller diameter in

Economic Optimization

π Profit $p Price $q Quantity unitsθ Quantity intercept  λp Price sensitivity  λd Design Sensitivity  Δα Change in feature  c Cost $β Part-worth  i Interest %n Period years

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INTRODUCTION

Take a look at the streets of Ann Arbor on any given day, and you will see how popular bikes are as a form of transportation around the town. Bicycles are not just popular in college towns, cities all over the US have people who commute to work on their bikes. Surely most students and adults who use bikes also possess cell phones and/or MP3 players. Why can’t bikers charge these devices while biking from place to place? Our proposal calls for a product that can seamlessly convert mechanical energy created while biking and store it in a rechargeable battery. This product would be unobtrusive and can charge electronic devices which have USB compatibility.

When brainstorming product ideas, we asked ourselves various questions about the marketing, demand, and the practicality of our product idea. From our survey results and product research, we discovered that our largest consumer market would consist of bicycle commuters and bike enthusiasts between the ages of 18 and 30. In the 2009 ACS, 0.55% of the American population commuted to work on bikes. If the US population consists of 250 million people, then there are over 1,500,000 Americans that bike to work every day. Our product promotes sustainability; there is a part of the bike community that is eco-conscious. Our product will also be appealing to those who enjoy “recycling” energy. Ideally, our product should encourage bike use and a healthy lifestyle. Our product should serve as positive reinforcement for healthy living and the welfare of the community. With a price that is cheaper than filling up a tank of gas, why not add a power source to your bike?

There is a list of demands that the product should meet to be competitive and appealing in the marketplace. As a bike attachment, it should be considered part of the bike. Therefore, it should be aesthetically pleasing, fit in with the design of a bike, and should also have protective housing that can withstand rain. The product should be durable, lasting at least three years. The product should be easy to install, and ultimately, the low cost of the product will differentiate it from any other similar product on the market.

This report will entail the research, analysis, goals, and projections for Eco-Spin. Our goal for Eco-Spin is profit maximization, however since Eco-Spin is a sustainable product, maximizing social benefit will also be considered.

PREVIOUS DESIGNSBicycles are natural power generators and there have been many attempts to harness the energy. The mechanical energy typically used for transportation can be converted into electrical energy due to the rotary motion of a bike.

Stationary bikes have been particularly popular to modify to gather electric energy. Bicycles are frequently used to power small electronic devices such as mounted lights and there are many devices currently available. They utilize various methods of power generation and a few examples are illustrated below.

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Pedal-A-Watt The Pedal-A-Watt system [1], shown in Figure 1 below, is a stationary power generator which is capable of generating on average between 125 and 300 Watts of power. It is sufficient to power a small microwave, toaster, and many other household appliances.

Figure 1: Pedal-A-Watt Generator

The Pedal-A-Watt Generator is very expensive and costs more than $400. It is also very limited because it forces the biker to be stationary. Another main drawback of this product is the fact that it has no energy storage. Thus, the appliance has to be placed near the generator accentuates the inconvenience of the design.

Battery-less Bicycle Flashing Lights The Battery-less Bicycle Flashing Lights device [2] uses a tumbling magnet electrical generating system to create an electrical pulse as the wheels turn to flash safety lights located in the front and back of the bicycle. This system generates essentially zero resistance while biking because the magnets on the spokes never touch the generator. The layout of the design is shown in Figure 2 below.

Figure 2: Battery-less Bicycle Flashing Lights

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This system does not have the capability of electrical storage with batteries. It only powers lights. The product costs between $20 and $30 dollars depending on the configuration, plus shipping from England.

Watts Maker Cell Phone Charger Although not commercially available, the Watts Maker Cell Phone Charger [3] comes very close to our design idea. It uses a wheel mounted electrical generator to directly charge a cell phone while riding. The system is shown in Figure 3.

Figure 3: Watts Maker Cell Phone Charger

Some shortcomings of the device is the fact that this product does not have the ability to store power. The absence of battery system can also lead to unstable power or voltage supple which can be detrimental to the cell phone. Moreover, this product also produces large amounts of resistance for the user.

Hub GeneratorThere are a wide variety of hub generators commercially available which connect directly to the hub of a bicycle wheel. The most popular hub generator company is Dynamo [4]. Their product lines cost over $100 and provide a low resistance way to power a bicycle light. An example configuration is shown in Figure 4.

These hubs can also be used to charge small electronic devices such as cell phones or MP3 players. However, these hubs typically require a specific Dynamo tire frame and can be tricky to install. Dynamo only sells lights and has no battery or charger product available.

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Figure 4: Bicycle Hub Generator with Light

Eton American Red Cross Microlink FR160 Multipurpose Radio While not a bicycle powered charger, this hand-crank device charges its battery for an LED light, AM/FM radio and has a power USB port for charging devices via USB cable. It is available for $30 from REI [5] and uses coils and magnets to generate electricity.

Figure 5: Eton American Red Cross Microlink FR160 Multipurpose Radio

We plan to incorporate many of this device’s features into our design but our design uses a bicycle to power the battery instead of a hand-crank. This device is featured later in the Reverse Design section.

There is a market for devices which power electronics manually (via a bike or hand-crank). Many of these devices directly power the electronics and do not have a method for energy storage. We hope to reach into this market with our product but offer a better design which allows for energy storage with batteries.

CONCEPT GENERATION

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Based on the aforementioned requirements and assessment of competing products, our team developed preliminary concepts and designs. Some poor designs and ideas which did not meet the requirements were eliminated. Key concepts were combined together to develop the final product design and features. Alpha prototyped was made to help visualize what the product will be like. Reverse engineering was performed on a product with similar features to gain a insight on the energy generation and conversion mechanism.

Alpha Prototype/Rapid Prototyping

Figure 6: Alpha Prototype

The rapid prototyping portion of our design process consisted of using simple materials to construct a basic model of our product. This exercise helped us recognize any visual design flaws and helped to pinpoint the optimum placement location for our product on the bicycle frame. While this exercise did not address potential circuitry issues that might arise, it was overall a very helpful process and allowed our team to finally observe and analyze a 3D model of the product.

Reverse Design

The reverse design of the device divulges the electrical specifications needed within the housing of our product. Our reverse design target was the Eton emergency radio shown in Figure 5. Apart from the hand crank, the internal organs of our product will be very similar to that of the emergency radio. The hand crank generates electrical power which is then stored in the battery. The battery can charge USB devices, an LED flashlight, and a radio.

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Figure 7: The system incorporates a battery system to store energy

The ease of design for the circuit board was promising; the device itself essentially proved our concepts are all feasible. A bike will also be able to generate more power than the hand crank itself, and this will have to be accounted for in the beta prototype. The hand crank displayed an option of converting rotary mechanical power into electrical power.

The rotating magnet and magnetic coils will be our method of generating power as well. The attachment of our product to a bike wheel was not explored during our reverse design, and this type of contact will need to be researched before making a final decision.

Figure 8: Gear system and the armature

CONCEPT EVALUATION

Each concept we are evaluating should provide the same functionality based on our design requirements. Power generation directly from the bicycle drives these features and we came up

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with several concepts for generating this power. Three different mounting methods were examined for use as we move forward with our design.

Hub Generator

Hub generators are already commercially available. Our product would be similar and provide an efficient way to generate power to charge a battery.

Advantage(s):- Most aesthetically pleasing because it simply replaces an existing bicycle part instead of

adding additional components

Disadvantage(s):- High Cost- Difficult to assemble, requires entire wheel to be removed

Tumbling Magnet

A tumbling magnet concept is shown in Figure 9 below. It provides a less traditional method for bicycle kinetic energy conversion.

Figure 9: Tumbling Magnet Concept

Advantage(s):- Very little resistance for peddling- Cheap to manufacture

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Disadvantage(s):- Less potential for power generation- Installation could be a hassle

Wheel Wall Mounted Friction Drive

A friction driven wheel idea is shown in Figure 10 below.

Advantage(s):- Installation doesn’t require bike disassembly - Connection allows for a gear train to increase power potential

Disadvantage(s):- Without counter weights it could throw off the balance of the bicycle- Adds resistance to biking

Figure 10: Friction Drive Concept

Concept Selection

After examining each concept we decided that a friction drive could best meet our design requirements. It is easy to install and has the potential for large energy production at a low cost. We expanded upon this concept to change the mounting point on the wheel leading to the design illustrated in Figure 11.

Wheel Surface Mounted Friction Drive

Advantage(s):- Same functionality as wall mounted design with added bonus of being able to flip up to

remove resistance

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Disadvantage(s):- Developing a universal connection method may be challenging

Figure 11: Friction Drive 2 Concept

A Pugh chart comparing the four concepts and our design requirements reinforced our decision can be found in Appendix C.

Redefined Design

Moving forward with the wheel mounted friction drive mechanism, we developed a CAD model to mount on a model bicycle [6]. The current design is shown in Figures 12 and 13.

Figure 12: Location of Roller and PCB Housing on Bicycle

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Figure 13: Close up of Refined Design

The model incorporates our design objectives into a lightweight and compact design that charges a battery. An improvement that will be refined for the final design is the mounting feature. The current design uses production parts that should be upgraded for ease of installation. The design can also be developed to be even more compact.

The Beta Prototype is based on this current CAD model.

Beta Prototype

The Beta Prototype makes use of a Minoura BH-95 mount, the gear train from the Eton American Red Cross Microlink FR160 Multipurpose Radio, as well as fabricated housing components and drive axel. At this stage, the model only possesses the housing that transforms mechanical into electrical energy with a Coil inductor. It does not use this electrical energy to charge a battery as our final model will. Figures 14, 15, and 16 show the Beta Prototype.

The emergency radio was powered with a hand crank. The prototype utilizes all the components of the radio but will use the rotational motion of the bike tire instead of a rotating human hand. The product is split into two housings. The housing featured in the beta prototype consists of a cylindrical roller, drive shaft, gear train, and DC generator. The second housing will hold the PCB, battery, and USB slot and will be attached in a more accessible spot.

The build of the Beta Prototype revealed some design changes that models didn’t foresee. We will incorporate the following changes into the next prototype and the final design: The Radius of the friction wheel needs to decrease from 4 inches due to the torque it transmits on the housing. The friction wheel must be mounted from both sides in order to withstand the torque from the rear wheel while maintaining contact with the wheel.

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Figure 14: Beta Prototype Front View

Figure 15: Beta Prototype Roller View

Ultimately, the beta prototype is promising for our product outline. Using off the shelf products, the product with all the functionality we require can be made for 50 dollars. It is reasonable to assume that the manufacturer’s cost of the materials could fall below 30 dollars. Our product will be able to sell at a price far below any competitive products, though our final product will need a much more rugged design than the beta prototype.

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Figure 16: Beta side-view

Beta-Plus Prototype

The Beta-Plus Prototype expanded upon the Beta Prototype by increasing the stability of the friction roller as well as adding the PCB and battery. We continued to make us of the Eton American Red Cross Microlink FR160 Multipurpose Radio for all our major components. Figure 17 illustrates all the components of the Beta-Plus Prototype. Notably, the cylindrical roller has been reinforced and offers stability on both sides of the bar it mounts onto. The beta prototype consisted of a 4 inch cylindrical roller while the beta-plus uses a 3 inch roller. Even though 4 inches was an optimized number, the roller was too large and rubbed against the structure of the bike. Thus, the constraint for the roller diameter should be <= 4 inches.

Figure 17: Beta-Plus Prototype Side View

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The PCB sits on a standard bike rack for this version of the prototype. Our final design has it fixed to the frame as shown earlier in the CAD model. Figure 18 is a close up view of the PCB housing and USB cable. This prototype is fully operational and its functionality was demonstrated by charging a Blackberry Cell Phone at the University of Michigan Design Expo on December 9th, 2010.

Figure 18: PCB View

The PCB used in the Beta-Plus Prototype worked to charge the battery as well as the phone but it consisted of components unnecessary to our design. The PCB, DC generator, and batteries were extracted from the Eton hand-crank radio. All components of that model were still included on the board. This consists of the circuits for the AM/FM radio and flashlight as well as circuitry for the battery and power conversion. Because of these unnecessary components, the actual size of our PCB will be much smaller than our Beta-Plus prototype.

To ensure that the circuit would not blow out, members of our team turned the hand crank as fast as possible for thirty seconds. Thus, the maximum RPM that the rotor could handle was approximately 140 RPMs. This matches up nicely with our initial engineering optimization which found an optimal diameter of four inches for the cylindrical roller and an RPM of ~136.

ENGINEEERING FUNCTIONALITY ANALYSIS

When taking into account the optimization of our device, it is important to recognize the constraints. Namely, our product calculations are completely reliant on bicycle dynamics and the speed and power of the average bike user. The average speed of a commuting biker (10 mph) and a median bike diameter of 26 inches are constant inputs that are used to determine power generated. Ultimately, these inputs will lead to the electrical power generated and then stored in the battery. This battery will then discharge into a USB device. Obviously, the more energy stored in the battery the greater the energy that can be charged into a USB device (though the charging rate of a USB device from the product will be fixed).

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The angular speed and gear calculations are used to find the torque and velocity transmissions from the cylindrical roller to the rotor. The cylindrical roller is pressed into the back bike wheel, and is connected through a drive shaft to a gear train. Thus, the torque and velocity of the bike wheel can be converted into the torque and velocity transmitted into the rotor of the DC generator. Power generated is the product of torque and velocity and the mechanical energy of the rotor will be converted after an efficiency loss into electrical power that can be stored in the battery.

Subsequently, the solver model has two variables cylindrical roller diameter and gear train ratio. Due to the laws of physics which state that energy cannot be created or destroyed, power cannot increase from a transmission from the bike tire to the rotor of the dc generator. There will be actual losses in the reduction of radius size from a bike tire to the rotor diameter, but the ideal model suffers no change in power. Thus, torque and velocity are inversely proportional in the model. The torque generated is a constant predicted from estimations in bike tire inertia and angular acceleration.

Battery calculations were also used in consideration of the power generated. Battery capacities can be specified in either mA•h or w•h depending upon the situation. The internal battery will use w•h calculations because overall power capacity is most important. The time period of use is assumed to be a 30 minute commute. Rough estimations of charging times for external batteries uses mA•h as current capacity dictates charging efficiency and speed. Charging time is taken as the proportion between internal battery capacity and external battery capacity. An iPhone 3GS has a 1000 mA•h lithium ion battery and was considered the standard battery in our calculations.

In this optimization, the DC generator is assumed to have 50% efficiency. The size and rpm of the device is ignored, it is assumed that the DC generator will be built to achieve 50% efficiency. The two variables used to calculate power generated are gear train ratio and cylindrical roller. Gear train ratio ultimately doesn’t affect power generation, but it will be important to find the optimum input rotor rpm into the DC generator. The calculation entered into solver.

E=0.52× 0.8 × I × α × d t ×ω× πdr × 30

Where E is the power generated in an hour (W•h), I is inertia (lbm*in2), α is the angular acceleration (rad/s2), dt is the tire diameter (in), ω is the bike angular velocity (rad/s), and dr is the roller diameter (in).

The cylindrical roller is assumed to transmit 80% of power due to friction losses. The DC generator operates at 50% efficiency and the average commuter bike trip is assumed to be 30 minutes, or 50% of an hour.

Ultimately, this solver model is very limited for Eco-spin. Power generated in the bike will be highly dependent on efficiency losses that don’t occur in ideal calculations. Losses such as friction will affect the optimization of the product. An ideal optimization of the product would have a target objective of minimizing losses.

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EMOTIONAL AND AESTHETIC ANALYSIS

The intended emotional appeal of Eco-Spin lies in the fact that it promotes energy sustainability and encourages the user to go “green”. There are two options for our product and they would appeal to consumers differently. There is our normal product which focuses on profit maximization, and our “green” product that promotes sustainable living. In other words, the goal of our “green” product design is to use materials and components that don’t leave large carbon footprints. By advertising and implementing these environmentally friendly practices, our goal is to encourage the user to think twice about his personal energy consumption with the hope that Eco-Spin’s positive environmental impact will promote sustainable living and a healthy lifestyle.

Furthermore, along with promoting an eco-friendly product, we intend to make our final product as aesthetically appeasing as possible. Eco-Spin has an engineering goal of being inconspicuous to the user, thus our aesthetic design will also mimic this style. The overlying shapes of the product will be two housings and the cylindrical roller. The housings will be a dark translucent color so that the inner electronic components don’t “jump out” at the user, but are still visible to visually remind them of what Eco-Spin is accomplishing.

MICROECONOMIC & MARKETING ANALYSIS

The main objective of the microeconomic modeling is to determine the optimal selling price to maximize profit. In order to determine this selling price, it is necessary to estimate the cost and market demand of the product. This section will discuss in detail the production and business costs as well as the market demand based on the survey results.

COSTAll costs associated with the manufacturing, production, and distribution of Eco-Spin. Costs can be divided into fixed costs which will be expected annually regardless of quantity produced, and variable costs, which are the per unit costs of production.

Fixed CostsFixed costs can be broken down into First Year Sunk Costs and Fixed Variable Costs. First Year Sunk Costs are costs associated with the development of the product, manufacturing process, testing as well as the R&D department. Fixed Variable Costs are costs associated with the operations of the factory which include salaries and administrative costs such as rent, utilities and insurance.

First Year Sunk Costs       $720,000  Design Engineering $145,000    Manufacturing Process Development $125,000  

 Manufacturing Equip. & Initial Tooling   $410,000  Testing Equipment $40,000

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Fixed Variable Costs       $900,000  Employees $500,000    Marketing $200,000    Cleaning & Equip. Maintenance $30,000    Facility Rent (8500 sq. ft.) $42,000  

Utilities $11,000Insurance $75,000Safety $25,000Miscellaneous Expenses $17,000

Table 1: Fixed Costs Associated with Eco-Spin

These are the costs estimates in order to bring Eco-Spin into production. First year sunk costs are fixed costs that only need to be paid to start up production. Fixed variable costs are annual, thus the first year there will be a total of 1.6 million dollars, while the following year would cost $900,000.

These were the assumptions used for first year costs. Design Engineering can consist of hired engineers or the hiring of an outside firm to optimize product functionality. Manufacturing process development will require at least one engineer. Though we are renting the facility, all equipment and tooling will be bought. An injection molding machine will be needed for the plastic housings, but the housings are relatively small and consequently only a small injection molding machine is needed. Soldering and electrical component stations will be needed along with mills and the standard assembly lines. Additional testing equipment will also be necessary.

These were the assumptions for fixed variable costs. Our estimations include 10 salaried employees who will manufacture the product. Marketing will be an important component of our annual fixed costs. Rent for an 8500 sq. ft. facility was available in Ann Arbor for five dollars per square foot. Cleaning and equipment upkeep also calculate into our expenses. Utilities were taken to be approximately 25% of the rent. Insurance, safety, and miscellaneous expenses are also taken into account.

Variable CostsVariable costs are associated with the manufacturing of each unit. These costs arise from material costs, packaging cost and hourly line worker wages. For a more detailed Bill of Materials with sources, see Appendix L.

Material Costs       $24.70  Cylindrical Roller Aluminum $2.00    Roller Cover Rubber $0.60    Spur Gears Aluminum $4.10    Roller Housing w/ Mount Plastic $1.30    DC Generator $2.00    Battery Housing Plastic $1.30  

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Battery NiMH $7.00PCB $5.00Wiring $0.30Mount for PCB Housing Aluminum $1.10

Packaging Cost       $0.50Variable Costs (per item)       $25.20

Table 2: Variable Costs Associated with Eco-Spin

PROFIT OPTIMIZATION (ENGINEERING MODEL)Based on the cost and revenue approximations, a profit optimization model was developed to fulfill the engineering objectives of the product. For this engineering-oriented product, a Nickel Zinc (NiZn) battery will satisfy the basic expected performance. The NiZn battery will have a charging time of 40 minutes and a lifetime of 1 year. NiZn will also be the battery utilized in our “green” design. Figure 19 below shows the demand, cost, revenue and profit/loss when fulfilling the engineering objectives is the main goal of developing the product.

It can be seen that when only the engineering objectives are considered in developing the product, Eco-Spin will not be profitable due to the demand level being too low to generate enough revenue to outweigh the production costs.

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Figure 19: Profit Optimization of Engineering-Oriented Product

In order to make Eco-Spin profitable, it is necessary to account for customers’ needs and preferences. Concordantly a survey was conducted to potential customers. Based on the survey results, the price and design sensitivities of the product were quantified and a more holistic and comprehensive model was developed which substitutes microeconomic objectives for engineering objectives. The findings are detailed in the Design Sensitivity section below.

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PROFIT OPTIMIZATION (ENGINEERING AND MICROECONOMIC OBJECTIVE)The main objective of the economic analysis is to determine the selling price that will maximize profit. Knowing the price sensitivity as well as the production costs and taking into account customers’ needs and preference through the design sensitivities, the profit optimization formula can be written as

π=p ∙ (θ− λp ∙ p+λd ∙∆ α )−cπ=p ∙ (θ− λp ∙ p+λd ∙∆ α )−c¿−cvariable ∙ (θ− λp ∙ p+λd ∙ ∆ α )

Price SensitivityThe price sensitivity (λp) is the change in consumer demand when the price of the product changes. The sensitivity can be determined based on consumer survey and scaling the result to the target market size. Using the equation

q=θ−λp ∙ pwhere q is the demand, θ is the quantity intercept, and λp is the price sensitivity. Based on the CBC survey conducted, the price sensitivity can be seen in Figure 20 below.

Figure 20: Price Sensitivity Figure 21: Charging Time Sensitivity

Design SensitivityDesign sensitivity (λd) is the change in consumer demand when one or more features of the product are altered. In the case of Eco-Spin, the charging time, product lifetime and size are the features that will deter or encourage buyers to buy the product. The sensitivities can be quantified based on the survey result and the value of the change in feature (Δα). Taking into account price and design sensitivities, the new demand can be can be determined by using the equation

q=θ−λp ∙ p+ λd1 ∙ ∆ α 1+λd2 ∙ ∆ α 2+λd 3 ∙ ∆ α 3

Based on the CBC survey conducted, the design sensitivities can be seen in Figure 21 above and 22, 23 below.

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Figure 22: Product Lifetime Sensitivity Figure 23: Product Volume/Size Sensitivity

Linear equations were fitted to the levels and part-worths in order to calculate the design sensitivity of the variables. The levels used in the Volume/Size category are approximate volumes as the survey asked consumers whether they’d prefer the size to be that of common household objects such as a tissue box. The data from the CBC is analysis is listed below in Table 3.

Name Level Part-Worth

Price($)

25 0.512

35 -0.073

45 -0.439

Charging Time(Min)

20 0.75140 -0.037

60 -0.714

Product Lifetime(Years)

1 -0.6493 0.2235 0.426

Volume / Size(in3)

30 0.448

70 0.034110 -0.482

Table 3: Part-Worth Values for the Price and Design Attributes

As shown in Figure 24 below, using the price and design sensitivities quantified from the CBC survey results, the maximum profit is achieved when Eco-Spin is sold at $40 per unit. At this price level, the demand and profit are 500,000 units and $5,635,000, respectively. This version of Eco-Spin utilizes a Nickel-metal Hydride (NiMH) battery unit which has shorter charging time of 30 minutes and longer lifetime of 5 years. In our profit optimization model, three types of batteries were used as variables rather than using the solver equation. While the engineering optimization found electrical power generated, the economic optimization goes a step further and considers the power capacities of batteries on the market.

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Figure 24: Profit Optimization with Engineering and Microeconomic Objective

NET PRESENT VALUE & CASH FLOWUsing the aforementioned revenue and costs estimates, a net present value and cash flow projections were performed in order to determine the profit projections of Eco-Spin. Some assumptions that were made throughout this process include:

Constant interest rate Stable economic condition No increase in component costs Fixed product price Customer demand will behave similarly to our survey results

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Figure 25: Three-Year Projection of Cash Flow and Net Present Value

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Year Income Payment Cash Flow NPV1 3,155,262 -3,457,815 -302,553 -100,7812 4,461,004 -3,898,075 562,929 557,1233 8,400,000 -6,792,000 1,608,000 2,046,000

Table 4: Three-Year Projection of Cash Flow and Net Present Value

As can be seen in Figure 25 and Table 5 above, for the first year of operations, it is predicted that Eco-Spin will have negative cash flow and net present value; a situation that is very common in newly launched products. Even though an initial investment should provide positive cash flow in the first year, low production numbers and little market penetration will leave Eco-Spin in the negative for the first year. However, NPV jumps to a positive value in the second year which situates the break-even mark between the first and second years. This matches up with our break-even analysis performed below, which predicted a total time of 1.28 years. Eco-Spin will see a positive cash flow and net present value for the first time as the market begins to expand and more products are sold in the second year. Payments in the second year consist of the annual costs and a dividend payment (30% of the profit) to investors. In the third year, Eco-Spin will go into full production and will sell in stores nationwide. After the third year, investors should expect to see a positive return on investment as all investment money is returned.

BREAKEVEN POINTA breakeven analysis was also performed for Eco-Spin based on the pro-forma calculations.

NormalFirst-year Sunk Cost ($) 720000Fixed Cost ($) 900,000Variable Cost ($) 25.20Selling Price ($) 40Annual Income ($) 1,498,000Interest Rate (%) 6

Table 6: Pro-Forma Statistics

(First Cost on annual basis) + (Operating Cost) = (Annual Income from Rent)

First cost∗i (1+i )n

(1+i )n−1+¿cost=Annual Income

Annual income was taken as the average of profit and investment in the first 3 years. A 10% markup was also added into the profit margins of the pro-forma model. Salvage values were low since a factory was rented and not bought, and equipment salvage values were considered to be negligible. Costs were already given and an investment of 1,000,000 dollars is assumed. The demand model was created based on our market expansion and demand projections below.

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Interests were given as 6%. Based on this calculation, it was determined that the breakeven point for regular Eco-Spin is approximately 16 months or 1.28 years.

MARKET EXPANSION & DEMAND PROJECTIONInitial market ranges will be dictated by the bicycle commuter population. Currently, no market exists for electronics charging bike accessories. Some bikes gather power but they are stationary. Some bike accessories use a roller similar to ours yet they only power headlights. Other accessories require installation and even the purchasing of a new bike tire rim. The product will be inexpensive and USB compatibility will be appealing to a wide variety of consumers. Consequently, our target market will be bicycle commuters. They tend to use the bike for long and constant periods of time, and all commuters surely have a phone. Commuters are just the initial market; Eco-Spin will also be attractive to college students, healthy bike enthusiasts, and eco-conscious people.

Eco-Spin will first be sold in cities in the state of California in the first year. This is based on the assumptions that the climate in California is more agreeable and Californians are usually considered to be more environmentally conscious. All data was extracted and interpolated from the American Consumer Survey (ACS) 2009, conducted by The Census Bureau. This annual survey tracks the amount of people who commute to work using bicycles. This information supports the trend of growth in the percentage of bike commuters, let alone the growth in the actual population from year to year. Nationwide percentages are given along with the percentages of the top 90 bicycle commuting cities.

In our initial three year period, we expect to sell 500,000 units total. This would be 33% of the bicycle commuter market share. In the first year of production, Eco-Spin will be sold in sporting goods stores and bicycle stores in California as well as online. Market projections for the first year were aggregated from the California surveys in the ACS. The following year, Eco-Spin will be marketed in the West Coast of the United States, namely Oregon and Washington and possibly Arizona. Cities in these states were added into the market size. In the third year, Eco-Spin will be marketed nationwide. This expansion will coincide with full-scale production of Eco-Spin. Thus, in the third year a total market size of 500,000 is targeted. Figure 26, 27 and Table 7 and below show the market expansion, demand and market share projections. Note that the total quantity sold over the three year period falls under 500,000 units, signaling unique consumer purchases throughout the three year period.

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Figure 26: Eco-Spin Market Expansion

0 1 2 30

100000

200000

300000

400000

500000

600000

Market SizeProduct Demand

Year

Am

ount

(x10

00)

Figure 27: Eco-Spin Market Size and Demand

Year 1 Year 2 Year 3Market Size 112253 253466 500000

Demand 53882 111525 210000Market Share 0.48 0.44 0.42

Table 7: Market Size and Demand

SUSTAINABILITY ANALYSIS

Eco-Spin is inherently conscious of the environment since it recycles power to charge electronics with little added effort by the user. It can take your phone or other small electronic device “off the grid”, allowing you to power your phone with just your own body.

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Eco-Spin is inherently a “green” product, but our sustainability analysis explored how “green” Eco-Spin really is. Our plan consists of materials that will help achieve our goal of profit maximization. If our business objective was social benefit, then the exploration of non-toxic Eco-Spin components would be necessary. Both options will be explored in the sustainability analysis.

Battery selection was considered with both traditional nickel-metal hydride (NiMH) rechargeable batteries as well the more environmentally friendly lithium ion (LiIo) or nickel zinc (NiZn) rechargeable batteries. Because LiIo and NiZn are similar in nature and data for NiZn couldn’t be found, a comparative life cycle assessment (LCA) can be calculated comparing only the batteries.

Two different methods of comparison from the SimaPro database are used. The Environmental Design of Industrial Products (EDIP) and Eco-Indicator 99, results are shown for each respectively in Figures 28 and 29 below. It is important to note that there is no data available currently for NiZn batteries so the comparison is only between LiIo and NiMH batteries. We will assume that the NiZn batteries will have similar (or even better) results than the LiIo because it uses non rare earth metals and has extremely good recycling potential.

Figure 28: EDIP Comparison of LiIo Battery (Left) and NiMH Battery (Right)

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Figure 29: Eco-Indicator 99 Comparison of LiIo Battery (Left) and NiMH Battery (Right)

These figures show that both the EPID and Eco-Indicator 99 indicate LiIo batteries as a more environmentally friendly alternative by about a factor of 2. Cost aside, if LiIo batteries last at least half as long as the NiMH batteries, they are better for the environment.

PRODUCT DEVELOPMENT PROCESS

Figure 30 below shows our initial process diagram from the beginning of the project. Figure 31 is a Design Structure Matrix (DSM) from the end of the project that shows which tasks effect the completion of other tasks.

Our initial concept showed a much more linear process as the project matured, it was quickly realized that many tasks happen concurrently and effect the final result of other tasks.

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Figure 30: Process Flow Chart

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

1.      Brainstorm Design 1

2.      Survey/Info Gathering 2 X

3.      Alpha Prototype X X 3 X

4.      Reverse Design 4

5.      Define Objectives/Requirements X X X 5

6.      Project Proposal X X X X X 6

7.      Analyze/Optimize Engineering Analysis

X X 7

8.      Micro-economic Analysis X 8 X

9.      Market Research 9 X

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10.  CAD Model X X 10

11.  Beta Prototype X 11

12.  Progress Report X X X X X X X X X X X 12

13.  Marketing Models 13

14.  Business Plan 14 X

15.  2nd CBC X X 15

16.  Econ Analysis Revision X 16

17.  Beta+ Prototype X X 17

18.  Final Report X X X X X X X X X X X X X X X X X 18

Figure 31: Design Structure Matrix for Development of Eco-Spin

CONCLUSION

Eco-Spin reflects our team values by embodying the goals that we originally set out to accomplish. Our aim was to create an attractive product that the consumer would find highly useful and easy to operate (minimal assembly required). The team values include creating a product that: actively recycles energy, is reliable, and promotes fitness and a healthy lifestyle. Eco-Spin will be a relatively inexpensive product when compared to current products in bike accessories. A selling price of 40 dollars is comparable to filling a single tank of gas.

Eco-Spin is an innovative product that converts wasted potential energy into electrical energy to power portable electronic devices. Our product will incorporate a USB port so that users will have versatility in charging different electronic devices. In just 40 minutes of active biking time, Eco-spin will charge an iPhone 3gs, which houses a 1000 mAh cell phone battery. Furthermore, to regulate the charging cycle, we have implemented an internal NiMH rechargeable battery pack.

Our target market is people that commute to work using their bicycles. This market size represents 0.55% of the United States population and the highest concentration resides on the West Coast. For the first year, Eco-Spin will be marketed in California. By year three, our product will be sold nationwide and Eco-Spin’s market share will be 48%, 44%, and 42 % for the first three years respectively. An initial investment of 1 million dollars is required to start the production of Eco-Spin, and at a unit price of 40 dollars we will break even in approximately 16 months.

Our engineering calculations and beta-plus prototype have proven that the Eco-Spin is a realistic product. With low costs of materials and an untapped bicycle commuter market, Eco-Spin is

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poised to become a profitable product. With a sustainable design and a reinforcement of healthy living, who wouldn’t want to take this product for a spin?

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REFERENCES

[1] http://www.econvergence.net/Merchant2/graphics/00000001/electron.jpg

[2] http://www.freelights.co.uk

[3] http://www.wirefly.com/learn/wireless_news/bicycle-cell-phone-charger-creative-inventions-of-2008/

[4] http://www.bikedenver.org/bicycling-resources/ride-guide/bicycle-visibility/

[5] http://www.rei.com/product/791977

[6] Bicycle model from http://artist-3d.com/free_3d_models/dnm/model_disp.php?uid=270 3D Artist: Jaipur

[7] http://www.census.gov/newsroom/releases/archives/american_community_survey_acs/cb10-cn78.html

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APPENDIX A: ELECTRIC GENERATOR EFFICIENCY CALCULATIONS

Goal: To find the efficiency percentage for the conversion of mechanical energy to electrical energy

Average biker can produce 100 watts in an hour (athletes can reach up to 300 watts)

Average person bikes for half an hour, thus produces 50 watt•hours

iPhone battery has a capacity of 1200 mAh (mili-ampere•hours)

USB charges devices at 5 volts, thus 5 V * 1.2 Ah = 6 Watt•hours

iPhone could gather a full charge from a 30 minute bike trip with a conversion rate of 6/50=12%.

Our target conversion rate will be 12%.

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APPENDIX B: SURVEY AND RESULTS SUMMARY

Group 7 Survey(Ryan Ollie, Kent Utama, Joe Cha, Paul Von Hertsenberg)

Project Idea: Attachment to bike that converts mechanical energy into electrical and stores it in a battery. In turn, this battery can charge a USB based device or a headlight

What we expect to learn from the survey: How useful this item would be? Potential generated power based on the biking amount of the user. Any concerns they would have with our product

Ten Questions:

1. How often do you bike? – Multiple Choicea. 0-4 Times a weekb. 5-9 Times a weekc. 10-14 Times a weekd. More than 15 times a weeke. Neverf. Other: ______________

2. How often do you lock your bike to a rack per week? - Semantic Differential

0% of the time ----------------------------------- 100% of the time

3. How long do you bike per session? - Open Ended

4. What do you primarily use your bike for? - Constant Sum

Please assign a total of 100 Points to the following options __Leisure __Travel__Exercise

5. What feature would you most likely want to add to your bike? -Itemizeda. Collapsibleb. GPSc. Phone chargerd. Made of bamboo

Our concept is to be able to use the energy that you generate while riding a bicycle to propel you as well as charge your phone via a generator attached to the wheel. This would enable you to simultaneously ride and charge your phone.

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6. Given this information, if you added a phone charger to your bike, would you ride it ______

- Comparative More oftenLess oftenSame amount

7. Would you mind added resistance during your bike session if it charged your phone?

Please circle one: (Yes/No)

8. How often do you charge your phone while using your car? - Itemized Category a. Oftenb. Sometimesc. Never

9. Rank from 1 to 3 (one being most likely) what you most likely would prefer to charge/power during bike travel? - Rank Order

Cellular Phone ____MP3 Player ____LED Headlight ____

10. Do you have any concerns about biking with a battery attached to your bicycle? - Open Response

CBCWeight (weight of a football, weight of a brick, weight of a gallon of milk, weight of a bowling ball)Affordability ($25, $35, $ 45)Interface (Power outlet, USB cable, raw wires)

ResultsFrequency of biking:

0-4 Times a week (60%)5-9 Times a week (11.4%)10-14 Times a week (6%)

Never (20%)

Frequency of locking bike:All the time (60%)

¾ of the time (11%)½ of the time (3%)¼ of the time (6%)

Never (20%)

Riding Influence:More often (15%)

Same amount (82%)Less often (3%)

Resistance Influence:Yes (53%)No (47%)

Charge Phone in Car:Often (47%)

Sometimes (41%)

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Average length of time biking:21 minutes

Features Desired:Collapsible (35%)

GPS (38%)Phone charger (21%)

Different Materials (6%)

Never (12%)

What to Charge:Cell Phone (26%)MP3 Player (29%)

LED Headlight (44%)

Use of Bike:Leisure (26%)Travel (48%)

Concerns:

Most respondents seemed unconcerned (60%), some were concerned about weight (12%), while few others fear electrocution.

CBC:The CBC results were dominated by weight (weight of a football) followed by price ($25) then interface (USB).

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APPENDIX C: PUGH CHART

Design 1 Design 2 Design 3 Design 4

Design Criteria

Weight(1-5)

Friction Generator(side

mount)

Dynamo Hub Generator

Tumbling Magnet

Friction Generator (top mount)

Weight 3 80 50 90 80Lockable 4 -- -- -- --Efficient 4 60 100 40 60Safety 5 -- -- -- --Ease of

installation 3 50 0 50 50

Price 4 60 0 70 60Minimal Friction 4 30 70 100 60

Cost to manufacture 4 50 20 70 50

Environmental impact 4 -- -- -- --

Economic impact 3 -- -- -- --

Durability 4 60 80 40 60Noise 2 80 80 100 80

Practicality 4Market

demand & trends

4 -- -- -- --

Versatility 3 30 20 40 50Aesthetics 4 50 80 50 60Stability 5 40 100 90 100

Maintenance 2 50 30 50 50Power

generation 5 80 70 40 80

Weighted Totals 2580 2680 2970 3100

The Weighted totals of the first 3 designs are similar, the advantages of design 4 (ability to disengage resistance, center balanced with bike) lead to a higher weighted total.

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APPENDIX D: QFD

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APPENDIX E: GANTT CHART

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APPENDIX F: REVERSE DESIGN EXERCISE

1. What is the main functional task that the product is meant to accomplish? What other uses might it have?

The main functional task is to provide mechanically generated electricity for emergency survival situations (converted into radio signals, light, charging capability).

2. Who are the intended users and market for this product? Can it be used as is in the US and other countries or would it need modifications?

The intended users are all people who find themselves in potentially life-threatening situations and need a fast and reliable power source.

3. What is the price range for this product? What about its competitors? How large is the market for this product in the US? In other countries?

The price range of the product is $30-$35. Its competitors advertise their similar products for about the same price range. The market in the US is huge, due to the large number of outdoor enthusiasts.

4. How good is the product’s craftsmanship (i.e., the initial perception that this is a well-made, well-functioning, high quality product)?

The product is very aesthetically appeasing with a great color scheme. The plastic housing is thick and durable and the circuitry and chips are well assembled, making the product function very efficiently.

5. How do you think the product works? Be specific. What do you expect to find after disassembling it?

The product uses a rotational cranking motion to generate electricity and power a radio, flashlight, and USB charging port.

6. Begin disassembling the product. What is the function of each component?

There are thousands of components. However, they can be grouped into the housing parts (plastic coverings, screws, nuts, and Plexiglas screens), electronic components (circuit board, wires, batteries, and antennas)

7. How do the various components work together?

The mechanical cranking components create a mechanical force that is converted into an electrical current. The current runs through a complex system of circuitry and becomes usable electricity. It is divided between powering a light bulb, radio, and USB port.

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8. How was this component manufactured? What materials were used?

The plastic housing and plastic internal parts of the product were injection molded. All other metal components appear to be milled/lathed.

9. How might another device serve the same function as one or more of the existing components?

A bicycle wheel rigged with an opposing friction generating wheel would accomplish the same rotational motion when generating electricity.

10. Is there a more economical way to achieve the same functionality?

Essentially, there is no practical alternative way of generating the same amount of electrical power from an economic standpoint.

11. Is there a more environmentally sound way to achieve the same functionality?

NO.

12. Now that you have studied the product more closely, how would you modify the product to increase its market appeal? Modify its price? Effect its manufacture in other countries? Use in a global market?

In order to increase the product’s market appeal, we considered modifying the price and overall visual appeal to satisfy other foreign markets.

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APPENDIX G: USER SCENARIO

Write a short story of a user in the environment that your product will be used in. Give it some thought, and use details about the environment and the user. (Are there distractions around? Might the user have something else on his mind? Are her kids nagging her? Is the user a worker performing a repetitive or monotonous task?) If appropriate, describe the problem, difficulty, or aggravation that the user is facing (this should be the problem that you are trying to solve). The goal of this exercise is to help you to see the situation from the user’s point of view. Keep this scenario around and refer to it as you explore design alternatives. The scenario will also illustrate the need for your product, and it will highlight important issues that your product should address. These exercises can help you to avoid large oversights that can lead to a poor, difficult to use, or useless product.

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Adam Manson, your every day white collar worker, wakes up Monday morning ready for a new week of work. Adam maintains a very active lifestyle and enjoys biking the commute to work. It takes him 20 more minutes to get to the office, but he enjoys the benefits of biking instead of driving every day. Biking helps maintains his physique, cuts costs, and he avoids the emissions his car would emit every day on the way to work. Unfortunately, on this particular day Adam is ready to for work but his phone is on low battery. Adam simply could have forgotten to charge his phone the night before or perhaps his mischevious cat, Mr. Whiskers, turned off the surge protector in the middle of the night. Luckily, this is a non-issue for Adam since he has an Eco-Spin attachment on his bike. Any device Adam possesses with a usb charger (phone, ipod, etc.), can simply be plugged into the Eco-Spin and will be charged by the mechanical energy Adam expends on the way to work. With little added effort on Adam’s part, he can charge his phone while biking to work.

On Adam’s way home after work, he is not worried about the battery status of his phone. However, he is worried about how dark it has become and worries about biking in such conditions. Adam is not perturbed because he can simply switch the mode on the Eco-Spin and voila, the Eco-Spin headlight activates. Adam can safely bike home now in the dark.

APPENDIX H: TEAM ROLES

RolePrimary Team Member(s)

Administrator / Reviewer Monitors project and judges outcomes accurately. Sees the big picture. Compares results with goals.

Paul

Troubleshooter / Inspector Repairs problems and solves difficult impediments to progress.

Joe, Ryan

Producer / Test Pilot Brings tasks to fruition and reality. Treats tasks realistically. Pushes performance envelope. Makes things happen.

Kent

Manager / Coordinator Supervises and leads tasks. Encompasses a practical perspective. Focuses effort and saves time.

Paul, Kent

Conserver / Critic Preserves the team’s and project’s goals and concerns. Addresses aesthetic and moral issues.

Ryan, Joe

Expediter / Investigator Experiences the team goals, gets facts and know-how.

Kent

Conciliator / Performer Detects and fixes interpersonal issues. Paul, Kent

Prototyper / Model Maker Builds and tests rough prototypes. Kent, RyanVisionary Imagines various product forms and uses. RyanStrategist Speculates on and plans project and product future. JoeNeedfinder Evaluates human factors and consumer issues. Paul

Entrepreneur / Facilitator Explores new products and methods, inspirers and motivates.

Joe

Diplomat / Orator Harmonizes team, client, and customer. Ryan

Simulator / Theoretician Attempts to understand phenomena; analyzes performance and efficiency.

Kent, Joe

Innovator Synthesizes new products; improvises solutions. Ryan, Paul

Director / Programmer Supervises and leads tasks. Encompasses a practical perspective. Focuses effort and saves time.

Paul, Kent

There exist a variety of ways to describe and present team roles. One approach is to distinguish important roles according to titles and brief distinguishing features. The categorized roles are not meant to pigeonhole or otherwise limit a team. They are simply meant to provide guidance and assist us in understanding how a design team functions.

APPENDIX I: INFO GATHERING

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By now you should have an idea of what kind of information you don’t yet know and you need to find out. Make a list of how you intend to get that information. You may want to draw up a Gantt chart or a task list for each of the team members. How can you get the information that you need? Where can you look? Who can you talk to? Who can you talk to to find out whom you need to talk to?

- User interviews: Talk to people who could represent potential users (and other stakeholders) of your product. Who will you talk to? What kinds of questions will you ask?

Talk to bike enthusiasts, start up conversations at bike racks, catch them while they bike

- Expert interviews: Talk to people who know more about the product domain, environment, etc than you do. You may get questions answered quickly this way. Who will you talk to? What kind of questions will you ask?

Bike store employees (typically knowledgeable enthusiasts) for their own knowledge and possible community pooling as well

- Study users: Where can you go to watch users in their environment? Remember the IDEO video? Where do you plan to go to watch users at work? What things will you look for?

Watch bikers, check out bike racks to look for different styles of bikes for standardization of attachment

- Personal experience: What kind of personal experience do you plan to gain? Can you spend some time in the user’s environment? Can you go through the processes in the problem environment and encounter the problem yourself? What kinds of notes will you take?

I bike as well, typically stationary. I can get a feel for the watts calculated on a bike by a standard user

- Product domain: How will you find out what other products are out there? How will you compare products?

Most bike stores do not have our competitors in stock, thus info gathering through the internet and the reverse design of the emergency clock radio will have to suffice.

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APPENDIX J: OBSERVATION OF PEOPLE

LOOK AT WHO, WHAT, WHERE AND WHEN.ASK YOURSELF (AND OTHERS) "WHY"Who is the person?Can you tell whether they are a student?

Yes, they are students at UMCan you tell what their major might be?

Computer ScienceWhat makes you think that?

Their appearance, stereotypesAny thoughts about their interests or hobbies?

Computer games, watching football, sports

Who are they with? How do they relate to others?

They look pretty friendlyWhat does their posture and body language say?

They are in a hurryWhat is their social interaction style?

They look fairly approachable & friendly

How are they dressed?What are they carrying and how?

Backpack on their backWhat does that say about their situation or priorities?

They like backpack because it’s convenientHow would you describe their personal style?

Practical

What are they doing?Do they seem to be enjoying this? How can you tell?

Yes, they will stop doing what they’re doing if they don’t like itIf waiting, how are they passing time?

N/AWhat is the quality of their activity — Fast? Tentative? Impatient? Reflective?

FastDo they seem to have a plan or just going with the flow?

They have a plan on where they’re going

Where are they?What are the surroundings like? Crowded? Littered? Noisy? Calming? Attractive? Friendly? Clean? Artificial? Sterile? Crowded, noisy, a lot of studentsDoes this affect their behavior? How? Yes, they try to bike faster

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LOOK AT WHO, WHAT, WHERE AND WHEN.ASK YOURSELF (AND OTHERS) "WHY"

Who is the person?Can you tell whether they are a student?

Yes, they are students at UMCan you tell what their major might be?

Undecided (freshman)What makes you think that?

Their looksAny thoughts about their interests or hobbies?

Sports

Who are they with? How do they relate to others?

They look pretty friendlyWhat does their posture and body language say?

They’re comfortable around their friends, engaged in the conversationWhat is their social interaction style?

They look fairly approachable & friendly

How are they dressed?What are they carrying and how?

Backpack on their backWhat does that say about their situation or priorities?

They like backpack because it’s convenientHow would you describe their personal style?

Practical

What are they doing?Do they seem to be enjoying this? How can you tell?

Yes, they seem engaged in the conversationIf waiting, how are they passing time?

N/AWhat is the quality of their activity — Fast? Tentative? Impatient? Reflective?

Slow pacedDo they seem to have a plan or just going with the flow?

They are just going with the flow

Where are they?What are the surroundings like? Crowded? Littered? Noisy? Calming? Attractive? Friendly? Clean? Artificial? Sterile? Not too crowdedDoes this affect their behavior? How? Yes, they walk slowly while talking

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APPENDIX K: DESIGN FOR THE ENVIRONMENT WORKSHEET

MET Matrix Worksheet

Material Cycle | Energy Use | Toxic Emissions

(input/output) (input/output) (output)

_____________________________________________________________________________

Production and supply of all materials and components

Mining required for metal components, toxins and petroleum from injection molding of plastics, iron/other metals required for PCB. Attempting to make the design as small as possible to reduce materials.

_____________________________________________________________________________

In-house production

Input- raw materials, energy required for machining parts

Output- Waste materials, toxins from production

_____________________________________________________________________________

Distribution

Output- Emissions from trucks/boats/planes

_____________________________________________________________________________

Use:

operation

The use phase is the most environmentally conscious part of this product because it produces energy sustainably because the user is generating their own power.

servicing

Fabrication of replacement parts might be necessary if a failure occurs

_____________________________________________________________________________

End-of-Life system:

recovery

Metals can be recycled

disposal

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Solid waste from land filling, toxins and other emissions if incinerated

DfE Improvement Options Worksheet

DfE Strategies Improvement Options

1. New Concept Development

1. De-materialize

2. Increase versatility

2. Physical Optimization

1. Make as efficient as possible

2. Downsize

3. Increase versatility

3. Optimize Material Use

1. Use recycled metals/plastics

2. Minimize amount of materials used

3. Use by-products

4. Optimize Production

1. Use non petroleum based cutting fluids

2. Decrease production steps/parts

5. Optimize Distribution

1. Strategic factory locations to minimize shipping

2. Less packaging

6. Reduce Impact During Use

1. Difficult to change on our design but we could increase

positive impact during use with solar panels etc.

7. Optimize End-of-Life Systems

1. Recycle Metals/plastics

2. Offer ‘take backs’ on the PCB

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APPENDIX L: BILL OF MATERIALS

Part Name Qty MaterialMat cost Origin Process Assembly Add. cost

Total part cost Source

Cylindrical Roller 1 aluminum 2.00 Buy 2.00 A

Roller cover 1 rubber 0.50 Buy Bind 0.10 0.60

Gears 2 Spur 4.00 Buy Gear lubricant 0.10 4.10 B

Roller housing with mount 1 plastic .90 Make Injection molding Bind 0.40 1.30 C

DC generator 1 Mixed 2.00 Buy 2.00 D

Battery housing 1 plastic .90 Make Injection molding Bind 0.40 1.30 C

AA Battery 4 NiMH 7.00 Buy 7.00 E

PCB 1 Mixed 5.00 Outsource 5.00 F

Basic wiring 1 Wires 0.20 Buy Simple solder 0.10 0.30

Mount for housing 2 aluminum 1.00 Make Milling Screw 0.10 1.10

Packaging 1 cardboard 0.50 0.50 G

Total 25.20

A. http://tewarehouse.com/7-04115 B. Spur Rods come in 1 ft lengths, (1/2 inch spur gear) at http://www.mcmaster.com/#gears/=a4wa5q C. Simple Java calculator, inputted a total volume of 60 in3 and a thickness of .2, http://kazmer.uml.edu/Software/JavaCost/index.htmD. Toy DC motor, http://www.ecrater.com/p/4850802/small-dc-motor-for-electrical-tool-andE. 4 Sanya eneloop AA batteries, http://www.amazon.com/Sanyo-Eneloop-Pre-Charged-Rechargeable-Batteries/dp/B000IV2YLY/ref=sr_1_4?s=electronics&ie=UTF8&qid = 1292290032&sr=1-4F. http://www.ladyada.net/library/pcb/costcalc.html G. http://www.industryreserve.com/Box-Packaging-Inc-Ship-Box-8X6X6-866_p_63479.html

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APPENDIX M: ENGINEERING OPTIMIZATION

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