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GNEG 1103 Introduction to Engineering FALL 2013

Team Design Project

Portable Phone Charger

Project Presentation

December 2, 2013, 8:00- 9:15 A.M

Derek Richard, Jarod Brunick, Luis Ramirez, Mason Torgerson

Alex Stratigakis

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Abstract

This report explains the processes and steps we took to develop our product by using the Engineering

Design Method. From a feasibility study to the actual creation of our product this report follow our

progress.

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Table of Contents

Abstract---------------------------------------------------------------------------------------------------------------- 2

1.0 Introduction---------------------------------------------------------------------------------------------------------- 4

2.0 Requirements and Constraints----------------------------------------------------------------------------------- 5

3.0 Basic Features-------------------------------------------------------------------------------------------------------- 6

4.0 Engineering Design Method-------------------------------------------------------------------------------------- 6

4.1 Identifying the Need and Defining the Problem------------------------------------------------- 6

4.2 Assemble Design Team (operating Styles)-------------------------------------------------------- 7

4.3 Identify Constraints and Criteria for Success----------------------------------------------------- 7

4.4 Search for Solutions------------------------------------------------------------------------------------ 8

4.5 Feasibility Study----------------------------------------------------------------------------------------- 8

5.0 Preliminary Design-------------------------------------------------------------------------------------------------- 8

5.1 Analyze Potential Solutions-------------------------------------------------------------------------- 8

6.0 Detail Design--------------------------------------------------------------------------------------------------------- 9

6.1 Analyze Potential Solutions-------------------------------------------------------------------------- 10

7.0 Results and Conclusions------------------------------------------------------------------------------------------- 10

Appendices:

Appendix A Evaluation Matrixes

Appendix B Cost Structure

Appendix C Project Pictures

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1.0 Introduction

With cell phones become such an integral part of our lives many of us are now faced with the problem

of keeping our phones charged all day. With frequent use the phones we rely on run out of battery

power too fast for our lifestyles. We either have to plug our phone into a wall or car charger every

change we get or we can use one of the many rechargeable portable power packs that are available on

the market. These portable power packs, however, must be charged from the grid at one point or

another. What happens when we either don’t have time to charge these devices or there is no wall to

plug into?

This report explores three possible solutions to this problem. The criteria used in the selection of the

final product are safety, size, customization, power capacity, and weight. By using the engineering

design method, solutions are developed and the best design that fits the criteria, requirements, and

constraints is chosen. Finally the cost structure is explained and future improvements are suggested.

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2.0 Requirements and Constraints

Must be safe

Safety is always a key requirement. without a product being safe it cannot be marketed to the

public.

Must make a profit

For this project we are a start up company. for that reason we must develop a product that can

be manufactured to make a profit so that the company is sustainable.

$90 limit

We were given a $90 budget by NWACC for materials.

Available time to meet

All of our team members are enrolled in other classes and have lives outside of this project that

we had to work around in planning times when we could meet to discuss our project.

Must be small enough to fit in pocket without notice

We decided that for this product to be marketable it would need to be small enough to fit in a

pocket without notice.

Must be completed by 12/2/13

The completion date for our project was set by our instructor for Monday morning on the

second of December.

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3.0 Basic Features

Easy use plastic case

This means easy use for the operator in replacing batteries or charging device as well as making

it easy to assemble during the manufacture process.

Replaceable batteries

Replaceable batteries make it easy to charge on the go because there is no time needed to plug

the phone charger into the wall. All that has to be done when the batteries are drained is to put

new ones in the charger.

Simple one step charge process

Easy to use USB charging design. Just plug the USB cable that all smart phones charge off of into

the device, and it starts charging.

4.0 Engineering Design method

4.1 Identifying the need and defining the problem

At the beginning of the semester when we were trying to decided on a project, Mason had the idea of

doing a portable phone charger. All of us knew how fast the battery can drain on smart phones when we

use them a lot and also how hard it can be to find time to charge them on the go, so we decided to find

a better way. We realized that there were many different kinds of portable phone chargers already on

the market, but we had only seen ones that ran on a lithium-ion battery. These had to be charged from

the wall just like your phone. In the end, These devices could extend your battery life for up to three

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times as long. This was fine for urban everyday use, but not so good for an extended backcountry

environment or an emergency situation in which plugging into the grid is not an option. We looked

around but could only find one device that didn’t use the grid to charge its battery without an expensive

solar panel. Because of this we recognized the need for an inexpensive, durable, off grid, portable phone

charger.

4.2. Assemble Design Team (operating Styles)

At the beginning, deciding who to put on a team was difficult, but when we started evaluating our

operating styles we found it easier to build a team that would work well together. Our operating styles

were as follows.

Derek Richard – Catalyst/Visionary

Jarod Brunick – Director/troubleshooter

Luis Ramirez – Integrator/Harmonizer

Mason Torgerson – Administrator/Stabilizer

4.3 Identify Constraints and Criteria for Success

We had many criteria and constraints for the success of this project. The most important ones where:

Time

We were required to have this project done in time for the school engineering fair on December

third.

Aesthetics

We had to design a product that was attractive in appearance but still functional. with the size

of this project it wasn’t to hard to decide on the key aesthetic features.

Performance

We decided that the product would have compete with the existing competitor products in its

charge size. This determined the size of batteries we used.

Safety

This project was going to incorporate electronic parts so we had to think about the risk of

electrical shock or other electrical dangers when designing it.

Effect on Surroundings

The size of this project would make its effects on its surroundings minimal but it would need to

be able to fit in everywhere without being displeasing. It wouldn’t be able to make annoying

noises, look out of place, or cause unsightly marks on surfaces it came in contact with.

Availability

The charger would have to be ready to work at any time that the phone would.

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4.4 Search for Solutions

Originally we thought of many concepts for our design. The greatest variable was what kind of battery it

would use: AA, AAA, lithium etc. Also the number of each battery we would need and the electronics we

would need depending on these factors would be crucial to success.

4.5 feasibility Study

In our initial planning, as a group, we quickly narrowed our selection down to three choices for

batteries: AA, AAA, or Lithium-Ion. Mason also found the electronics required to charge a phone with

any of these choices.

Potential Solutions

AA batteries

AAA batteries

Lithium-ion battery

5.0 Preliminary Design

We created an evaluation matrix for our project and analyzed each solution with it to determine which

solution we would go ahead with.

5.1 Analyze Potential Solutions

Weight AA Batteries AAA Batteries Rechargeable Ion

Property W S S x W S S x W S S x W

Safe 5 5 25 5 25 0 0

Compact 3 5 15 5 15 4 12

Customizable 4 5 20 5 20 1 4

Ease of Use 3 4 12 4 12 4 12

Power Capacity 4 4 16 3 12 5 20

Weight 1 4 4 4 4 3 3

Total 92 88 51

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The lithium-ion batteries got such a low score because we found them unsafe for us to use. Mason had

the battery in his backpack when it started smoking and shortly after removal from his pack went up in

flames.

The AA and AAA batteries where close, but the power capacity of the AA batteries compared to weight

and size made it more fitted to our need.

In the end we decided to use AA batteries.

6.0 Detail Design

After deciding on the AA battery option we started to test the American made electronics we had with

the batteries. The original parts burned up on us, so we ordered some new imported parts that we knew

would work. These worked out great and we didn’t have any more problems with that part.

Once we had the electronics working we started on the design of the case for the electronics. We

decided to use a 3D printer to do a prototype. Starting with a simple box design we used this to figure

out the errors in the printers measurements and find a base design that would fit its purpose.

After finding the base dimensions we explored door designs that would enable the user to access the

batteries to replace them. We had three ideas.

Potential Solutions

Option 1 – One like those on the back of calculators that use a plastic latch built into the door

Option 2 – A sliding door like those on the fuse cover of Christmas lights

Option 3 – A pop off lid with two fingernail grooves to pull it off from the sides.

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6.1 Analyze Potential Solutions

Based on the ease of use, the durability and the easy of manufacturing, we decided to use the Option 3.

Property Weight Option 1 Option 2 Option 3

W S SxW S SxW S SxW

Ease of use 5 4 20 4 20 5 20

Durability 5 5 25 4 20 4 20

Ease of manufacturing

4 2 8 3 12 5 20

Option 1 Score = 53

Option 2 Score = 52

Option 3 Score= 60

7.0 Results & Conclusions

Based on the decisions we made about our product, we ended up with a cell phone charger that uses

two AA batteries and charges a phone through a USB connection. The case is made of durable ABS

plastic and one side lifts off to allow access to the batteries inside. It allows the use of a wide range of

batteries including rechargeable AA batteries and is extremely versatile in its ability to be used in nearly

any environment needed by an average human being. The size of this charger is small enough to go

unnoticed in a pocket and is safe for human use. Last of all the cost is low enough to make It affordable

for everyone (see cost structure in appendix B). Considering our options, we believe this to be the best

solution to the problem identified at the beginning of this report.

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Appendix A Evaluation Matrixes

Evaluation Matrix A

Weight AA Batteries AAA Batteries Rechargeable Ion

Property W S S x W S S x W S S x W

Safe 5 5 25 5 25 0 0

Compact 3 5 15 5 15 4 12

Customizable 4 5 20 5 20 1 4

Ease of Use 3 4 12 4 12 4 12

Power Capacity 4 4 16 3 12 5 20

Weight 1 4 4 4 4 3 3

Total 92 88 51

Evaluation Matrix B

Property Weight Option 1 Option 2 Option 3

W S SxW S SxW S SxW

Ease of use 5 4 20 4 20 5 20

Durability 5 5 25 4 20 4 20

Ease of manufacturing

4 2 8 3 12 5 20

Appendix B Cost Structure

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Appendix C Project Pictures

The Initial Measurements

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The First Prototype

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The Final Print

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The Completed Product Straight Off the Printer