Revision History - wordpress.up.eduwordpress.up.edu/egr13peacocklane/files/2013/...2.docx · Web viewThe requirements section includes a block diagram of the major ... cells, harness

FUNCTIONAL SPECIFICATIONS VER. 1.0 10/4/2013TEAM PEACOCK LANE

Requirements and Functional SpecificationsSun Tracking Solar ArrayEE 480 SENIOR DESIGN PROJECT PREPARATION

Team Members:

Elise King (Fall Team Lead)

Caitlin Greeney (Spring Team Lead)

Beverly Raposa

Julius Jose Raposa

Faculty Advisors:

Dr. Zia Yamayee (Primary)

Dr. Robert Albright (Secondary)

Client:

Dr. Heather Dillon - University of Portland

Industrial Advisor:

Jeffrey Cook -Bonneville Power Admin

UNIVERSITY OF PORTLAND SCHOOL OF ENGINEERING PAGE 1


Revision History

Ver. Date Author Reason for Changes

0.9 20 September 2013 Elise KingMade final edits before submitting to Dr. Yamayee.

0.95 27 September 2013 Beverly Raposa

Made specific additions to several sections and edited formatting. Added Revision history section

1.0 3 October 2013 Caitlin Greeney

Made grammar corrections. Made minor adjustments to content. Updated Revision history.



Table of Contents

TABLE OF CONTENTS___________________________________________________________________3

TABLE OF FIGURES_____________________________________________________________________4

TABLE OF TABLES______________________________________________________________________4

INTRODUCTION_______________________________________________________________________5

REQUIREMENTS_______________________________________________________________________7OVERVIEW:___________________________________________________________________________7CLIENT SPECIFICATIONS___________________________________________________________________8GENERAL SPECIFICATIONS_________________________________________________________________9TECHNICAL SPECIFICATIONS_______________________________________________________________10

USE CASES___________________________________________________________________________10USE CASE #1: CLASSROOM DEMONSTRATION__________________________________________________10USE CASE #2: 24-HOUR SUN TRACKING______________________________________________________11USE CASE #3: LIGHTING A HOME__________________________________________________________11

USER INTERFACE______________________________________________________________________12

DEVELOPMENT PROCESS_______________________________________________________________13

MILESTONES_________________________________________________________________________16

PRELIMINARY BUDGET_________________________________________________________________20

FACILITIES___________________________________________________________________________23

RISKS_______________________________________________________________________________23

CONSTRAINTS________________________________________________________________________24TECHNICAL__________________________________________________________________________24ECONOMICAL________________________________________________________________________25ENVIRONMENTAL______________________________________________________________________25SOCIAL_____________________________________________________________________________25POLITICAL___________________________________________________________________________25PROFESSIONAL_______________________________________________________________________25ETHICAL____________________________________________________________________________25LEGAL_____________________________________________________________________________25HEALTH/SAFETY______________________________________________________________________26SECURITY___________________________________________________________________________26MANUFACTURABILITY___________________________________________________________________27SUSTAINABILITY_______________________________________________________________________27STANDARDS_________________________________________________________________________27CODES_____________________________________________________________________________27



CONCLUSION________________________________________________________________________27

BIBLIOGRAPHY_______________________________________________________________________29

GLOSSARY___________________________________________________________________________30

APPENDICES_________________________________________________________________________31

Table of FiguresFigure 1: Block Diagram of Device__________________________________________________________________6Figure 2: User Interface_________________________________________________________________________12Figure 3: Development Process___________________________________________________________________14Figure 4: Light Tracker with 4 Solar Cells____________________________________________________________29Figure 5: Sun Tracker with Single 4 Cell Panel________________________________________________________30Figure 6: Arduino Control of Two Servos____________________________________________________________31

Table of TablesTable 1: Milestones____________________________________________________________________________15Table 2: Initial Budget__________________________________________________________________________18



Introduction

In 1931, Thomas Edison told his friends Henry Ford and Harvey Firestone, “I’d put my

money on the sun and solar energy. What a source of power! I hope we don’t have to wait until

oil and coal run out before we tackle that” (Rogers). Edison had the right idea; the sun’s energy

is ever present and just waiting to be harnessed into usable energy. Solar energy involves the

use of photovoltaic cells that allow the sun’s energy to be converted to energy that can be used

for everyday purposes. As the demand for energy continues to increase, the need for

renewable energy sources becomes more and more important. If we want to insure that there

will be resources in the future and that non-renewable sources will not be depleted, the focus

needs to switch to renewable sources. One important renewable source that needs to be

harnessed is the sun! Since solar energy is still a relatively expensive method for producing

power, it is very important to maximize the power output. Tracking the sun is one way to

increase power production by 30-40%.

This is where Team Peacock Lane’s sun tracking solar array comes in. The goal is to

design and construct a solar array that can track a light source or the sun. The idea of being able

to track a light source is critical to our project because its main purpose is to be used as a

teaching device. Dr. Dillon, a mechanical engineering professor at the University of Portland,

has asked for a demo that she can use to teach about solar and energy production in her

laboratory classes. The goal is that students will be able to interact with the array by moving a

light source and the solar panels will move with the light to adjust the angle and direction for

the greatest energy production. Students will also be able to easily gather information about

voltage, current and position on a user-friendly display.

The basic design of this project consists of a small solar panel that is mounted on a rack

system, which can self-adjust three dimensionally using two servos. We plan to construct a

small cone that will have four photoresistors mounted to its surface. The cone will then be

mounted on the frame that holds the panel. The photoresistors are very sensitive to light and

will be able to sense minute changes in light intensity. An Arduino microcontroller will take the

photoresistor information and adjust the solar panels to the best location to produce maximum



energy. The Arduino will be programmed to determine which photoresistor is the brightest and

then moves the servos to point the panels in the direction of the highest intensity of light. The

Arduino will continue to check and adjust the panels to keep the brightest point in the center.

We chose to use an Arduino microcontroller because of its ability to control multiple servos and

control an output display.

The key features of the design are the ability to see in real time how movements of a

light source affect production output of a solar array and to be able to clearly communicate

data to students during the demonstration. The device needs to be portable so that

demonstrations can be performed during lab or lecture in different classrooms. It would also be

beneficial to the client if the device could be mounted on the roof in order to provide students

with data as the device tracks the sun across the sky. An important feature of the device is

providing data to students during a demonstration. The student should be able to see the

voltage and current values that cause the panels to move to their optimal orientation.

This document will explain the requirements and functional specifications for this

project. The requirements section includes a block diagram of the major components of the

device and specifications for its functionality. We will also address the use cases and user

interface of this device. The development process, milestones, preliminary budget, facilities,

risks and constraints will also be discussed. At the end of this document is a glossary of

technical terms that are significant for the understanding of the project.



Requirements

Overview:

The main components of the Sun Tracking Solar Array can be found in the block diagram below:

Light Source: Solar energy is the analog input signal into the system. It will be in the form of a

light source such as a light bulb or the sun.

Photoresistors: When light of a certain frequency falls on a photoresistor, electrons begin

moving causing a current. Thus a current can be drawn from the photoresistor load and a

power measured.

Solar Cells: Solar cells, also called photovoltaic (PV) cells, harness solar energy and convert it to

electrical energy. PV cells are made mostly of the semiconductor material silicon, which absorbs

the sun’s energy and allows electrons to flow freely in the silicon. An electric field is intrinsic to

the PV cell.


Figure 1: Block Diagram of Device


Servo Motor: These motors will change the position and angle of the frame to which the PV

cells are attached, allowing the device to point towards the brightest source of light.

Arduino: Arduino boards are an “open-source electronics prototyping platform based on

flexible, easy-to-use hardware and software”. This will function as the “brain” of the device by

taking in the information from the photoresistors, performing logic on the information, telling

which servo motor to move and sending voltage and current information from the solar panels

to the display.

External Power Source: The Arduino requires a power source to function.

Display: This will display the current and voltage measurements from the PV cell.

Client Specifications

Portability: Dr. Dillon requested that the device be transportable from a classroom on the first

floor of the Shiley School of Engineering building to the roof where the device would observe

the sun for an extended period of time. Since there are at least two flights of stairs and several

doors to maneuver, this device will most likely be mounted on a custom frame made to fit

through the doors properly. There is also a possibility of mounting the frame on a cart to make

it more convenient to transport.

Lab View: Dr. Dillon requested that the information gathered by the Arduino, which will be

used to make the decision to move the servomotors, be available to students using the

program/device Lab View. Since the device will be mainly used for classroom demonstrations

for mechanical engineering students, using familiar programs in the mechanical engineering

program will work best for Dr. Dillon and her students. Real-time voltages, currents, power and

position will also be displayed. Students are not given access to data over an extended time

period, so using two methods to gather data is the best option.



Extended vs. Classroom Use: Dr. Dillon would like to use the device for classroom

demonstrations and for potential lab exercises on the roof of the engineering building. In

addition to portability, mentioned above, this presents two requirements:

Durability: Since this device has the potential to be moved often and used outdoors,

there should be some type of water-proof casing for the electronic devices. There is the

possibility of creating a custom-made Plexiglas casing for the electronics.

Motors: Using the tracking device to track the sun outdoors and to track a halogen light

indoors, will cause two different movements: slow, over a 24 hour period and fast, over

a few seconds. As a result, the device will need servomotors that can handle both types

of movement. However, using a stepper motor is also a promising compromise for both

kinds of movement.

General Specifications

Aesthetics: Since the tracking device will be moved often (see Portability) the device and its

frame must be designed in such a way that the size, shape and weight are within the user’s

ability to move. In general, the device and frame must be able to fit through a standard

doorframe and be lighter than 150lbs (given the assumption that two average persons would

be used in transport of the device and frame).

Noise: Since this device will be used indoors in a smaller classroom setting, the noise level

should not harm the user. The only parts of the device that could potentially cause noise are

the servomotors. In general, the noise level should not exceed 60dB (normal conversation

levels).

Endurance: Since the device will be moved often, it must be able to endure basic abuse that is

caused by bumping against walls or doorframes during transport. See “Aesthetics” above for

further discussion.



Interaction: Since this device will be used in lab and as a demonstration for mechanical

engineering students, the device must be able to connect into a Lab View device for laboratory

purposes and data collection.

Technical Specifications

Power: The Arduino requires an external power source to function. This will most likely be a

battery capable of producing 5V; however, there is also a possibility that a properly functioning

device will be able to generate enough electricity to power itself under direct sunlight.

Coding: Since an Arduino microcontroller is the device platform, knowledge of the coding will

be required to create an algorithm to move the servomotors.

Welding: Since the device will require a frame, knowledge of welding and how to design a

sturdy structure to support the device is necessary.

Use Cases

Use Case #1: Classroom Demonstration

Primary User: Student/ Professor

Goal: Fast tracking of a halogen light source

Scenario: The Sun Tracking Solar Array has been set up in the front of a classroom. The

professor hands a student a halogen light source and asks him/her to shine it on the solar cells

by moving the light in an arc above the device. The student does so and the device follows the

halogen light source in the same arc pattern.

Potential Problems: Other sources of light in the classroom could obscure the ability of the

device to track the halogen light source. The halogen light may not be bright enough or may be

too far away.



Fixes: Dim the lighting in the classroom and verify that the halogen light source is close enough

for the tracking device to sense.

Use Case #2: 24-Hour Sun Tracking

Primary User: Student

Goal: Slow tracking of the sun and data collection over a 24-hour period

Scenario: The Sun Tracking Solar Array, with its frame, has been set up on the metal mounts

provided by the school on the roof of the Shiley School of Engineering. The data collection

device, Lab View, has been successfully connected to the Arduino in the Sun Tracking Solar

Array. The device is left to track the sun in its arc through the sky throughout the day, and data

is collected the following day using the Lab View program.

Potential Problems: Without a clear sky, the sun’s rays can be scattered (through clouds),

which would make it more difficult for the device to track a clear light source throughout the

day. Any rate of precipitation is a potential harm to the electronics used in the device as well as

in the data collection device, Lab View.

Fixes: When collecting long-term data, check the weather to work on clear days so the device

can function at its peak. In case of unexpected precipitation, the Plexiglas casing built into the

design should offer sufficient protection from the elements. However, the casing should be

checked for any cracks prior to outdoor use.

Use Case #3: Lighting a Home

Primary User: Average Homeowner

Goal: To supplement the power needed to light a home

Scenario: The Sun Tracking Solar Array and its frame has been successfully set up in a

residential backyard, away from any overhead obstruction that could obscure the sun from



reaching the device. The array is left to track the sun year-round to provide electricity to the

home.

Potential Problems: Since the Arduino requires energy to function, there is a risk that the

device will utilize more energy than it produces over a year long period, especially if the

weather is naturally overcast, like it is in the Northwest.

Fixes: Having the option to only use the Sun Tracking Solar Array during sunnier months could

prove to be more efficient than having it track year-round for home power production. Another

consideration would be upgrading to a different device to control servo movement that does

not need an external power source.

User Interface

The user interface consists of a Nokia 5110/3310 monochrome LCD, which displays the

measured angles in the x-axis and y-axis, current, voltage and power produced. By displaying

these values, the user can collect data that shows which angle produces the most power. Figure

2 illustrates what a possible user interface would look like.



Figure 2: User Interface

The user can also interact with the device by shining a flashlight onto the solar panel

and photoresistors, causing the device to move and orient itself toward the light and adjust the

angle of the panel for maximum power production.

Dr. Dillon has also asked Team Peacock Lane to incorporate Lab View data collection to

the project because it is a program that mechanical engineering students are familiar with. The

user interface for Lab View is a program on the computer that students can use to analyze data.

This program will be especially important with tracking the sun over a 24-hour period when it is

mounted on the roof.

Development Process

In order to accomplish the goal of creating a Sun Tracking Solar Array, the team will split

the overall developmental process as illustrated on Figure 3. After the initial planning through

the project proposal, functional specification and design document, the construction of the



actual device will begin. The team will acquire a solar panel donated by the City of Portland.

These panels will be examined for compatibility with the device and individual solar cells will be

purchased if necessary. Beverly and Caitlin will learn to program the Arduino Microcontroller

and develop an algorithm for determining the angle for maximum power production. Julius will

examine the solar cells for collection and measurement of power, voltage and current. Elise will

connect the motors and servos to the solar panel. The team will collaborate from there to

connect all the components within the frame in order to construct the whole device. Once the

device is functional, testing and debugging will be performed. The functionality of the device

will be presented on Founder’s Day and documented in the Final Report.


Functional Specifications

Design Document

Program Arduino Microcontroller

Assemble Breadboard

Examine Solar Panels

Construct Device

Test and Debug

Founder’s Day Presentation

Final Report

Project Proposal



Figure 3: Development Process


Milestones

Table 1 lists the milestones necessary for the completion of the project.

Table 1: Milestones

Number DescriptionMajor/Minor

Completion Date

1 Functional Specification v0.9 Minor 20-Sep-13

2 September Program Review Minor 27-Sep-13

3 Functional Specification v0.95 Minor 27-Sep-13

4 Project Website Launched Minor 27-Sep-13

5 Functional Specification v1.0 Major 4-Oct-13

6 Acquire Solar Panels Minor 11-Oct-13

7 Component Selection Completed Major 25-Oct-13

8 October Program Review Minor 25-Oct-13

9 Design Document v0.9 Minor 1-Nov-13

10 Design Document v0.95 Minor 8-Nov-13

11 Design Document v1.0 Major 15-Nov-13

12 Final Budget Major 15-Nov-13

13 November Program Review Minor 22-Nov-13

14 All parts ordered Major 29-Nov-13

15 All parts received Minor 17-Jan-14

16 January Program Review Minor 24-Jan-14

17 Arduino Microcontroller Functional Major 24-Jan-14

18 Breadboard Functional Major 7-Feb-14

19 February Program Review Minor 14-Feb-14



20 Frame Received Minor 14-Feb-14

21 Device Constructed Major 21-Feb-14

22Device Testing and Debugging Completed Major 7-Mar-14

23 Final Report v0.9 Minor 21-Mar-14

24 Final Report v0.95 Minor 28-Mar-14

25 Final Report v1.0 Major 4-Apr-14

26 Final Program Review Minor 4-Apr-14

27 Founder’s Day: Project Presentation Major 8-Apr-14

28 "Post Mortem" Presentation Minor 17-Apr-14

Functional Specification v0.9: First draft of the Functional Specifications is submitted to Dr.

Yamayee for review and revision.

September Program Review: Elise King will give a presentation regarding the progress of the

project to students and faculty. Team members will be introduced, background information on

the project will be given, major milestones and a block diagram of the device will be explained.

Design challenges, important decisions and risks will be discussed.

Functional Specification v0.95: Second draft of the Functional Specifications is submitted to

Dr. Yamayee and industrial advisor for review and revision.

Project Website Launched: The Project Website, which allows public access to documents,

regular project updates and team member contact information is launched.

Functional Specification v1.0: Final draft of the Functional Specifications is submitted to Dr.

Yamayee, Dr. Albright and industrial advisor for approval.



Acquire Solar Panels: Solar panels donated by the city of Portland are acquired and inspected

for compatibility with the project.

Component Selection Completed: All project components are selected for purchase,

including the Arduino Microcontroller and breadboard, servos and motors, solar cells (if

necessary) and other hardware necessary

October Program Review: Julius Jose Raposa will give a presentation regarding the progress

of the project to students and faculty. Completed and upcoming milestones will be highlighted,

design components will be presented and concerns will be discussed.

Design Document v0.9: First draft of the Design Document is submitted to Dr. Yamayee for

review and revision.

Design Document v0.95: Second draft of the Design Document is submitted to Dr. Yamayee

and industrial advisor for review and revision.

Design Document v1.0: The final draft of the Design Document is submitted to Dr. Yamayee,

Dr. Albright and the industry advisor for approval.

Final Budget: The Final Budget, which includes all component costs and other projected costs

is submitted to the EE/CS faculty

November Program Review: Caitlin Greeney will give a presentation regarding the progress

of the project to students and faculty. Technology used in the project will be demonstrated.

Completed and upcoming milestones will be highlighted, and concerns will be discussed.

All Components Ordered: All project hardware including motors, servos, wires, resistors, etc.

are ordered. This milestone does not include the Arduino Microcontroller and breadboard and

display as these will be purchased ahead of time for characterization.

All Components Received: All project components will be received and stored in the Senior

Design Lab until project construction.



January Program Review: Beverly Raposa will give a presentation regarding the progress of

the project to students and faculty. Evidence of project construction will be presented.

Completed and upcoming milestones will be highlighted and concerns will be discussed.

Arduino Microcontroller Functional: Algorithm for maximum power detection is functional

and microcontroller is programmed.

Breadboard Functional: Breadboard is wired to the Arduino Microcontroller, servos, motors

and solar panel. Both Arduino and breadboard are capable of moving solar panels for maximum

power production.

February Program Review: Julius Raposa will give a presentation regarding the progress of

the project to students and faculty. Evidence of project construction will be presented.

Completed and upcoming milestones will be highlighted and concerns will be discussed.

Frame Received: Frame is constructed and received from Engineering Technicians.

Device Constructed: The device is constructed with all the components including the Arduino

Microcontroller, breadboard, motors and servos, solar panels and frame. At this point, the

device is functional, but may have bugs.

Device Testing and Debugging Completed: All necessary testing and debugging for the

device must be completed.

Final Report v0.9: First draft of the Final Report is submitted to Dr. Yamayee for review and

revision.

Final Report v0.95: Second draft of the Final Report is submitted to Dr. Yamayee and

industrial advisor for review and revision.

Final Report v1.0: The final draft of the Final Report is submitted to Dr. Yamayee, Dr. Albright

and the industry advisor for approval.

Final Program Review: Team Peacock Lane will give a presentation regarding the progress of

the project to students and faculty. A background of the project, design methods, product



architecture and data collected will be presented. Issues will be discussed and the functional

device will be demonstrated.

Founder’s Day: Project Presentation: Team Peacock Lane will give a presentation

highlighting the functionality, uses and other aspects of the project. The device will be

demonstrated.

“Post Mortem” Presentation: Team Peacock Lane will give a presentation on aspects that

contributed to the success of the project and areas for improvement to students and faculty.

Preliminary Budget

The following table, Table 2, lays out the initial budget for this project.

Table 2: Initial Budget

Part Description Qty Rate Subtotal References

Arduino Starter Kit

Starter Kit for Newsite Uno R3 - Bundle of 6 Items: Newsite Uno R3, Breadboard, Holder, Jumper Wires, USB Cable and 9V Battery Connector

1 $ 34.00 $ 34.00 1. http://www.amazon.com/Starter-Kit-Newsite-Uno-Breadboard/dp/B0051QHPJM/ref=sr_1_3/183-4237672-5937057?ie=UTF8&qid=1379626898&sr=8-3&keywords=arduino+starter+kit

*Servo Motor Hitec 33485S Deluxe HS-485HB Karbonite Gear Servo Specs : Motor Type: 3 Pole Bearing Type: Top Ball Bearing Speed (4.8V/6.0V): 0.20 / 0.17 sec @ 60 deg. Torque oz./in. (4.8V/6.0V): 72 / 89, Torque kg./cm. (4.8V/6.0V): 5.2 / 6.4 Size in Inches: 1.57 x 0.78 x 1.49, Size in Millimeters: 39.88 x 19.81

2 $19.00 $38.00 http://www.amazon.com/Hitec-33485S-Deluxe-HS-485HB-Karbonite/dp/B002HPUKS8/ref=sr_1_14?ie=UTF8&qid=1379628345&sr=8-14&keywords=servo+motors



x 37.85, Weight ounces: 1.59, Weight grams: 45.08

Nokia Monochrome LCD Display

Nokia 5110 LCD Screen: The Nokia 5110 LCD is low-cost, monochrome LCD display with 84x48 resolution. It is often used for 8-bit AVR/PIC projects.

1 $6.00 $6.00 1. http://learn.adafruit.com/nokia-5110-3310-monochrome-lcd/overview 2.http://www.amazon.com/Nokia-5110-LCD-Screen/dp/B0068EUIXG/ref=sr_1_5?ie=UTF8&qid=1379628569&sr=8-5&keywords=nokia+monochrome+lcd+display

Photoresistors 20pcs Photo Light Sensitive Resistor Photoresistor Optoresistor 5mm GM5539 5539 Specs:Maximum Voltage: 150 Volt DCMaximum Wattage: 100mWOperating Temperature: -30 ~ +70 deg CSpectral Peak: 540nmLight Resistance (10 Lux): 50-100 Kohm

1 $13.00 $13.00

*Plexiglass Acrylic Sheet, Transparent Clear, 3/8" Thickness, 12" Width, 12" Length (Pack of 1)Specs: Brand NameSmall Parts Part NumberSLU-0375-C Overall Length12 inches Length Tolerance+0.000/-0.187 inches Thickness3/8 inches Thickness Tolerance+/-0.03125 inches Width12 inches

Ads2

$40.00 $40.00 http://www.amazon.com/dp/B000FPC3F0/ref=biss_dp_t_asn



LowerTemperature Range-20 Degrees Fahrenheit Upper Temperature Range170 Degrees Fahrenheit FinishSmooth Indentation Hardness90-103 rockwell_M Pkg Qty1 Tensile Strength Max 10000 PSI

Total: $131.00*denotes that materials may be obtained through the University of Portland without any costs to the team

All parts and components will be purchased through the Electronics Technician. Based

on the preliminary budget, the estimated cost of the device is within the allotted budget of

$300. The cost of the device depends greatly on the functionality of solar panels donated to the

school and the availability of servos that were recycled from previous senior design projects.

Facilities

This project will require the standard senior design lab room with access to specific lab

equipment. Access to computers/laptops, Lab View and basic circuit analysis tools are

necessary. In addition, access to tools for building the frame and casings for the project, which

include welding and wood tools, are also necessary. For testing purposes, access to the roof of

Shiley, which will be the test site for long term tracking abilities of the device, is necessary.

Risks



With any technical project there are expected risks throughout the process. The

following are risks that have been considered and contingency plans for what should be done if

the situation does arise.

1. Trouble may arise with the mechanical aspects of the project. Due to inexperience with

mechanical parts, a potential issue includes interfacing the solar panels with the servo

motor.

Contingency: Ask a mechanical professor or mechanical technicians for assistance on

development and assembly. Dr. Dillon has offered to help with mechanical components

that the team may not have experience with.

2. The team may not be able to satisfy all of the client’s specifications, such as the ability of

the device to slowly track the sun over a 24 hour period and do fast moving classroom

demonstrations. Issues may arise because specific motors are designed for optimal

ranges of speed and accuracy. (servo motors vs. stepper motors)

Contingency: If the device is incapable of adapting to both speeds, the team will focus

on the functionality for classroom demonstration. A motor with optimal speed for

making quick movements given a short amount of time will be selected.

3. While ordering materials, the team may receive some defective parts.

Contingency: If there is enough money in the budget, extra parts will be ordered as a

backup for the key components. The team will also order parts early and test for

defectiveness early on in the process so that there is enough time to return and

exchange faulty products

4. Working with Lab View may present issues because no one in the team has experience

with the program.

Contingency: If issues with Lab View arise, Dr. Dillon, who has experience with the

software and says that it is easily adaptable and easy to troubleshoot, will be consulted.



5. The solar panels donated to the school may be too large and the servos may not be able

to support and move the panels.

Contingency: Order appropriate sized panels that are compatible with the specifications

of the project or consider purchasing larger motors.

6. If milestones are over due and deadlines are missed, the team may be off track with the

schedule for the rest of the project.

Contingency: To insure that this does not become an issue, steps to achieving each

milestone will be decided and delegated long before the deadline of each milestone. If

milestones or deadlines are missed, the task should be completed within two days of

the original deadline and team members not involved with the milestone should step in

to assist.

Constraints

Technical- The project relates to technology because solar energy is continuously developing

and improving. As technology advances, solar power becomes more and more realistic and

affordable. The project focuses on tracking the sun, which is the type of technology used to

maximize power output. The team hopes the device will help bring awareness of solar energy

and sun tracking technology.

Economical- Tracking the sun makes solar more efficient, however significant costs in

production and maintenance are added. As technology further develops, the cost for

production and maintenance should decrease.

Environmental- Solar is a great source of clean energy. Solar energy helps to offset carbon

emissions and is not harmful to the environment. The project in particular will hopefully bring

awareness to students that solar is a great alternative to non-renewable resources.



Social- Since this project will be used for demonstration purposes, the social aspect is

important. Students need to be able to understand and gather information from viewing the

device. Also this project will hopefully inspire discussion about solar and green energy practices.

Political- Government initiatives and incentives make solar more affordable and economical.

Since the cost of solar is quite high, government subsidies help make solar projects possible.

Government support for solar projects will make the development of solar a quicker, more

affordable process.

Professional- Sun tracking solar does not specifically apply to professional constraints, but

there are professional engineers that focus on these technologies.

Ethical- Clean energy is increasingly becoming an ethical obligation. As non-renewable energy

sources are being depleted, it is crucial for research and development to focus on green

projects. The team practices good ethics by educating students about solar and tracking

technology, which are clean energy alternatives to fossil fuels.

Legal- According to the Legal Intelligencer, there are ten legal issues in solar energy projects,

which include:

1. Transaction Structure- Power purchase agreements (PPA), solar system ownership and

solar system leasing.

2. Incentives- Federal investment tax credit, grants, rebates and other loan programs.

3. Financing- Determines how the balance of the solar development will be paid for and

secure financing as necessary.

4. Location, Zoning & Permitting- Ensures that the project can be constructed in

compliance with all applicable environmental, land use and zoning requirements and

that all the necessary permits to construct and operate the system can be timely

obtained.

5. Engineering, Procurement & Construction- Gaining the appropriate assistance with

components of the project that is out of the scope of the client.



6. Energy Regulation- Concerned with interconnection with the energy grid becoming a

producer of power instead of just a user.

7. Renewable Energy Credits- Environmental credits that evidence the generation of clean

renewable energy. States require that a specific percentage of the power sold by utilities

in the jurisdiction come from renewable sources.

8. Allocation of Risk- Operational and regulatory risk. The owner of a solar system relies on

the system’s performance, yet a variety of factors such as component defects, shading,

and severe weather may adversely impact performance. Also regulatory programs or

incentives are not always guarantied over long periods.

9. Operations and Maintenance- Solar systems require periodic maintenance and repair in

order to operate efficiently and reliably.

10. Market Conditions- Market conditions could change, affecting numerous aspects of a

solar project. Return on investment could be altered if the price for power increases or

decreases.

Health/Safety- In general, solar panels are safe and effective. Compared to burning fossil

fuels, PV systems do not produce the toxic air and greenhouse gases. According to the U.S.

Department of Energy, only a few power-generating technologies have as little environmental

impact as photovoltaic solar panels. However, there are potential health and safety concerns

with the manufacturing and disposal of solar panels.

Security- Using a more diverse spectrum of energy sources, including clean energy, would

lessen the demand for foreign oil and other fossil fuels in the U.S. Being able to produce enough

energy to support the needs of the U.S. would be a big step to becoming a fully sustainable and

self reliant country, which would greatly affect its national security.

Manufacturability- Solar panels are manufactured in large-scale factories. This project

would need to be further developed before considering mass production. The Arduino is a good

option for small-scale development, but would not be very efficient for mass production. In

addition, larger panels and larger motors will be necessary if this device was designed for large-

scale power production.



Sustainability- The development of clean energy technology is a significant step toward

sustainability. If the amount of non-renewable resources being utilized for energy production

can be limited, this would insure that other resources will be available in the future.

Standards- The North American Board of Certified Energy Practitioners (NABCEP) is the “gold

standard” for PV and Solar Heating Installation and PV Technical Sales Certification. NABCEP

aims to raise industry standards and promote consumer confidence in solar.

Codes- The Solar America Board for Codes and Standards (Solar ABCs) collaborates and

enhances the practice of developing, implementing, and disseminating solar codes and

standards. The Solar ABCs provide formal coordination in the planning and revision of solar

codes and standards. This collaborative effort also provides access for stakeholders to

participate with members of standards, making bodies through working groups and research

activities to set national priorities on technical issues.

Conclusion

The Sun Tracking Solar Array will be designed and built to track a light source or the sun

for maximum power production. This device will provide the client, Dr. Dillon, with classroom

demonstrations to educate students about solar and its energy generation. The device will be

used in a classroom setting with a light source or mounted on the roof of the engineering

building to track the sun for a 24-hour period. This document highlights the requirements, use

cases, user interface development process and milestones involved in the project. The

preliminary budget, facilities, risks and constraints were also addressed. Team Peacock Lane

looks forward to designing and building a successful device to help promote knowledge of solar

energy and the benefits of sun tracking technology.



Bibliography

Arduino - HomePage . (n.d.). Arduino - HomePage . Retrieved September 11, 2013, from

http://www.arduino.cc/

Gotanda, B. H., & Reiter, D. (2011). Fueled by the sun: 10 sizzling Legal issues in solar energy

Projects. The Legal Intelligencer, 243(113), 0.

How do solar cells work?| Explore | physics.org. (n.d.). physics.org | Home. Retrieved



September 14, 2013, from http://www.physics.org/article-questions.asp?id=51

NABCEP. (n.d.). NABCEP. Retrieved September 13, 2013, from http://www.nabcep.org/

Nokia 5110/3310 monochrome LCD + extras ID: 338 - $10.00 : Adafruit Industries, Unique & fun

DIY electronics and kits. (n.d.). Adafruit Industries, Unique & fun DIY electronics and

kits. Retrieved September 16, 2013, from http://www.adafruit.com/products/338

Properties of Sound Waves - Sound Waves for Merit Physics. (n.d.). Sound Waves for Merit

Physics - Home. Retrieved September 15, 2013, from

http://meritsoundwaves.weebly.com/properties-of-sound-waves.html

Rogers, H. (n.d.). THE WAY WE LIVE NOW - 6-03-07 - RECONSIDERATION - Current Thinking -

NYTimes.com. The New York Times - Breaking News, World News & Multimedia.

Retrieved September 20, 2013, from http://query.nytimes.com/gst/fullpage.html?

res=9F0DE2DC1430F930A35755C0A9619C8B63

Solar ABCs: Codes & Standards. (n.d.). Solar America Board for Codes and Standards. Retrieved

September 12, 2013, from http://www.solarabcs.org/codes-standards/index.html

http://www.oregon.gov/ODOT/HWY/OIPP/docs/life-cyclehealthandsafetyconcerns.pdf. (n.d.).

Oregon.gov. Retrieved September 15, 2013, from

www.oregon.gov/ODOT/HWY/OIPP/docs/life-cyclehealthandsafetyconcerns.pdf

Glossary

Photovoltaic (PV) - device used to convert solar radiation into direct current electricity

using semiconductors that exhibit the photovoltaic effect.

Arduino microcontroller - an open-source electronics prototyping platform based on

flexible, easy-to-use hardware and software. It's intended for artists, designers,

hobbyists and anyone interested in creating interactive objects or environments.



Photoresistors- When light of a certain frequency falls on a photoresistor, electrons

begin moving causing a current. Thus a current can be drawn from the photoresistor

load and a power measured.

Servo motor - rotary actuator that allows for precise control of angular position, velocity

and acceleration.

Lab View - system-design platform and development environment for visual

programming language. Can be used for data acquisition and analysis..

Voltage - change in potential energy between two points.

Current - net flow of charges per time.

Power - rate of change of energy with time. Power= Voltage X Current.

Multimeter - device used to measure voltages and currents.

Appendices

The final device may look similar to the devices found in Figure 4 and 5. An example of how an Arduino can be used to control multiple servos is shown in Figure 6.



Figure 4: Light Tracker with 4 Solar Cells



Figure 5: Sun Tracker with Single 4 Cell Panel



Figure 6: Arduino Control of Two Servos


Documents

Revision History - wordpress.up.eduwordpress.up.edu/egr13peacocklane/files/2013/...2.docx · Web viewThe requirements section includes a block diagram of the major ... cells, harness