Teams in Engineering ServiceMiddle School Environmental

Education Team Spring 2009

Jose AlonsoConnie CheungScott Hollwedel

Jeremy JungBlayne LenoirHared Ochoa

Armita PebdaniZach Salin

Alan ToledoAlan Turchik

Julianna WangYon Xiao

Table of Contents

1. Introduction......................................................................32. Quarter Goals....................................................................33. Handheld PM Sensor..........................................................4

Background...............................................................................................4ADC Program.............................................................................................4Assembly...................................................................................................5Testing......................................................................................................6Vernier Sensor Attachment.......................................................................7

4. Lesson Plan Development..................................................75. Classroom Visits................................................................8

Introduction...............................................................................................8Coordinating Visits....................................................................................9Contacts..................................................................................................10Lesson Plans............................................................................................10

6. Assignment Antarctica Game............................................137. Preuss Science Olympiad..................................................148. Lesson Plan Additions......................................................15

Introduction.............................................................................................15Food Batteries.........................................................................................15UV Photography......................................................................................16

9. Budget............................................................................1810. Appendix.......................................................................19

i. PM Sensor Parts.....................................................................19ii. Air Filter Lesson Plan.............................................................19iii. ADC Source Code...................................................................................20

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1. Introduction

The main goal of this project is to increase interest in science and engineering in young students, with an emphasis on middle school girls. Studies have shown that this is the age group where the interest in science and engineering takes the most dramatic downturn. In order to accomplish this goal, this team focuses on several key components with a variety of functions. This team visits classrooms to assist teachers involved in theI-TEST program, helps to test an educational computer game set in Antarctica, and develops environmentally oriented lesson plans. To enhance the lesson plans the team designs and builds a variety of equipment. One of the main areas is the use of particulate matter sensors due to the everyday impact that particulate matter has in an area that is prone to fires.

While still fulfilling the main overall goals of this team, this quarter the team concentrated on testing its handheld particulate matter sensor for optimum experimental conditions with the eventual goal of being introduced into classrooms along with complementing lesson plans. In addition, the team developed a lesson plan that focused on air filtration and proper protection against airborne matter. The team contacted the teacher in charge of Preuss School’s Science Olympiad and began mentoring teams on a weekly basis. Also, the team explored further into I-TEST lesson plans and sought to implement lesson plan concepts into contraptions appealing to middle school students. The team focused on the science behind food batteries and UV photography.

2. Quarter Goals Two Classroom Visits Per Team Member Assignment Antarctica Game Installations Handheld PM Sensor

o Reprogramming for Measurement Displayo Assembly of Two More Sensorso Lesson Plan Developmento Testing and Experimenting

Lesson Plan Additionso pH Scale and Food Batteries

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o UV Rays and UV Lenses

3. Handheld PM Sensor

Background

Air quality is becoming more of an environmental concern. Many daily and popular products emit pollutants that are deemed unhealthy, if not hazardous, to people’s health. Automobiles, for instance, emit carbon monoxide that is a colorless and tasteless yet highly toxic gas. Cigarette smoking as well as passive smoking provokes higher risks of asthma. Even common beauty supplies such as hairsprays contain many chemicals that result with various forms of irritation and nausea. Introducing students to air quality education at a younger age can teach awareness of these pollutants and, perhaps, inspire them to pursue and generate newer, environmental-friendly products and procedures.

This TIES team is developing a particulate matter (PM) sensor to accompany lesson plans on air quality. The main goal is to produce a light and portable system that allows students to manipulate and retrieve live data of the ambient air quality. This sensor is able to detect solid particles, such as dust and pollen, from 1 – 10 micrometers in size. This quarter the work on the sensor was mainly centered on tweaking the program running the sensor, assembling two more sensors, and testing.

ADC Program (Scott)

Some slight changes were made to the components on the newly built sensor. In particular, a much smaller Analog to Digital Converter (ADC) was used. Since we purchased a smaller ADC, we needed to alter stamp controller program to display the measurements, whether displaying each individual measurement or displaying an average of the measurements within a time frame. Figure 1. displays the pin outs from the stamp controller side.

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Instructions for Use of PM Sensor:1. The sensor must be vertical i.e. the screen should be pointed upwards.2. The screen should never read 0. If it does, the wire from the sensor to

the ADC chip is loose and needs be reattached3. Air flows from the bottom to the top so whatever source is being

measured should be on the bottom.4. The output of the sensor is usually variable due to the inherent

variability in the ambient particulate matter concentrations (picture a cigarette smoke plume which is far from homogeneous). It has been validated against a high grade PM counter. It was found that the average of the handheld sensor output matched the high grade PM counter. For typical clean indoor air expect readings of 123 particles per liter.

5. Use provided charger to recharge batteries.

Refer to A-ii for the ADC source code.

Assembly (Yon)

This quarter, we used a different Analog to Digital converter (ADC) than in previous quarters. The previous design called for a 20-bit ADC, which was more than necessary, so we went with an 8-bit ADC as a simpler model. The general pin outs of the ADC are displayed in Figure 3. We connected all the pins to the stamp controller by connecting VDD to pins 8 and 5 and grounding pins 1, 3, and 4. We connected the remaining pins to pins

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Figure 3: general pin outs of 8-bit ADC

Figure 1: pin out of 8-bit ADC from stamp controller

Figure 2: 8-bit ADC

connected to the stamp controller as they are used for the data in and out of the clock.

For the LCD Backlight Screen, we soldered wires to the RX, 5V and GND parts of the backside of the screen. This allowed us to connect the wires to the stamp controller so that it could receive an input and output to display desired results.

We needed to find connectors for the particulate matter sensor because we were missing some sets. We purchased a set of 3pin and 4pin connectors as shown and are figuring out ways to incorporate longer strands of wires to connect it to the stamp controller.

We assembled two more enclosures to hold the particulate matter sensors. We used 3/16-inch acrylic to assemble front panels and covers. Each component was glued together using acrylic cement/glue. The hardware was screwed in using 4-40 machine bolts and the complementing nuts and washers. The cover and battery plate are screwed to the front panel using 4-40 machine bolts. Prior to assembly, each hole was tapped for these bolts; not tapping these holes can possibly result with cracked acrylic.

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Figure 4: LCD schematics

Figure 5: 5pin connector

Refer to A-i for hardware parts list.

Testing (Alan Turchik)

Earlier this quarter we proposed assembling a box in order to test the handheld particulate matter sensor.  A box was made out of clear acrylic, approximately 9 x 9 inches. A square hole was made on the front face of the box at the bottom of the face in which the sensor could be inserted. The idea was that a smoldering object could be placed inside the box. The smoke would fill the box and the sensor could read the density of particles inside the volume of the box. Other ideas involving atomizing flour inside the box were considered for testing the sensor’s capability.

Initial testing consisted of placing smoldering incense inside the box with the sensor. Two major problems arose with the box design. First, the box had the sensor opening located on the bottom of the front face, with the sensor setting on the table on which the box was mounted. The main sensor inlet was located on the underside of the handheld sensor, so the opening in the box effectively blocked the sensor inlet. The other immediately visible problem was that the concentration of smoke in the box became too high too quickly. The particle concentration in the highly concentrated smoke quickly exceeded the measurement range of the sensor.

The solution to these problems include mounting the sensor opening higher and mounting a fan on the backside of the box for air circulation inside the box to ensure that concentrations did not increase significantly.  Below is a drawing of the proposed redesign of the box. 

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Figure 6: SolidWorks model of handheld sensor

When we find the optimum conditions for testing the sensor, we can compare our sensor with an accurate sensor in Prof. Kimberly Prather’s lab.

Vernier Sensor Attachment (Scott)

An idea we investigated this quarter was possibly adapting the handheld particulate matter sensors to use the Vernier LabQuest handheld unit. While the idea was feasible, the LabQuest software would have to be customized whenever using the sensor. The analog voltage from the sensor could be displayed on the screen for the Vernier LabQuest unit, but special parameters would have to be set on the unit to convert the voltage into a particulate matter count. This would be an added level of complexity when using the LabQuest unit. In this regard the unit would be more difficult to use than the standalone sensor, but would provide the advantage of being able to read and analyze time series rather than instantaneous counts.

4. Lesson Plan Development (Alan Toledo)This quarter we finalized and expanded on a previously developed

particulate matter (PM) lesson plan to help increase student knowledge of particulate matter. The original lesson plan introduced students to operating the handheld PM sensor by measuring the concentration of air samples. This quarter we sought to alert students about the effects of air filtration.

Air filtration is a concept that people practice daily—whether for work or for personal health—in order to prevent the passage of foreign particulate matter into or out of the respiratory system. Doctors use surgical masks in

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Figure 7: proposed testing box

order to prevent loose hair or spit from entering the patient as well as block any microbes or bacteria from entering their air passageways. Construction workers are constantly surrounded by air born debris and wear face masks in order to prevent inhaling particulate matter. A recent out break of the swine flu in San Diego caused some people to wear face masks to decrease their chances of contamination. In general, particulate matter is a known cause of respiratory illnesses such as bronchitis and aggravated asthma. By filtering air via handkerchiefs or masks, people try to limit their intake of particulate matter.

For this lesson plan, students measure an air sample and use that result as the control experiment. For each following measurement, students measure the same air sample with various materials separating the PM sensor from the air sample. Using multiple materials to filter the air sample, students will understand that particulate matter can penetrate some materials easier than other materials.

Refer to A-i for soft copy of lesson plan.

5. Classroom Visits (Julianna, Hared)Introduction

Throughout the quarter, TIES students participate in the project “Information Technology-Engineering and Environmental Education Tools” (ITEST1). ITEST is lead by UCSD Jacob’s School of Engineering, in partnership with the San Diego Super Computer Center (SDSC). ITEST works with San Diego middle school teachers to develop hands-on environmental science experiments, utilizing the Vernier LabQuest handheld sensors.2 TIES students attend middle school classes during these experiments, and provide technical and scientific support to the teachers while using the LabQuest sensors. The lesson plans and LabQuest sensors are designed to spark student interest in science and technology as well as increase student awareness about current environmental issues.1 http://ties.ucsd.edu/ITEST/aboutite3tools.html2 http://www.vernier.com/labquest/

Coordinating Visits

A TIES team member is assigned as the teacher visit coordinator at the beginning of each quarter. The coordinator is responsible for arranging the visit schedule which best accommodates both teachers and TIES students. The following is a guideline on how the organization can be done efficiently:

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1) Access ITEST coordination website to obtain equipment rotation schedule. The rotation schedule provides information on which teacher(s) will have the equipment during which week(s). Passwords can be obtained from the TIES team advisors.

2) Contact teacher(s). Contact the teacher(s) a week in advance to inquire their class schedule (day and time). This is done primarily on email, and preferably on Monday to give the teachers time to respond.

3) Create online poll. After obtaining teachers’ schedule, create an online poll (www.doodle.com). The rest of the team will provide their availability using the poll, and the coordinator can decide on the visit time that best accommodate both the teacher(s) and the TIES students. The poll is generally created on Wednesday.

4) Inform the teacher(s) of the visit times. After obtaining the result from the poll, the coordinator will contact the teacher(s) with the visiting times for the following week. This is also done via email, preferably early Thursday so the teacher(s) will have time to respond before the weekend. Ask the teacher(s) to respond in email as a confirmation on the schedule.

5) Confirm with teammates. Upon receiving the confirmation from the teacher(s), inform teammates with date, time, and location of the visit.

6) Online Survey. After each visit, participated TIES students are required to fill out an online survey form for the ITEST research team to gather data about the lessons.3 Additionally, participants need to answer the following questions to complete the survey process (email to peterman@grginc.com):

Teacher Name:

Observation Date:

How prepared was the teacher to lead the lesson you observed? (Choose one)

a) Extremely prepared – he/she had seemed to have reviewed the lesson plan ahead of time, the lesson seemed to be implemented according to a clear plan, and the teacher experienced few (if any) hiccups

b) Generally prepared – he/she seemed to have reviewed for the lesson and seemed to have a general plan, but the lesson would have benefited from more specific planning

c) Unprepared – he/she had not reviewed the lesson beforehand and/or did not seem to have a clear plan for the lesson

Why did you choose that rating? (No more than a few sentences)3 http://www.grgsurvey.net/cgi-bin/rws3.pl?FORM=LessonReportCard

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Contacts

Questions regarding overall ITEST operationJulie Humphrey jchumphr@ucsd.edu

Equipment (Vernier LabQuest & Sensors) AllocationEzequiel Noyola enoyola@ucsd.edu

Teachers involved in the Middle School classroom visitsTeacher School Contact InfoJill Anderson Joan MacQueen Middle School janderson@alpineschools.netBrenden Casey Joan MacQueen Middle School BCasey@alpineschools.netBuster Diggs Joan MacQueen Middle School tigertanker2003@yahoo.comKatie Harris O'Farrell Community School krunner696@aol.comPaul Hannasch O'Farrell Community School phannash@ofarrell-mail.sandi.netGwendolyn Fairley SD School of Creative and Performing Arts gfairley@sandi.netRyan Gallagher High Tech Middle School rgallagher@hightechhigh.orgSean Gardinier Correia Middle School sgardinier@sandi.netVicki Bauer National City Middle School vicki.bauer@suhsd.k12.ca.usSarah Carlock Emerald Middle School luv4n6@cox.netDenise Ingram Los Coches Creek Middle School nesicow@yahoo.comKaren Madsen Wangenheim Middle School kmadsen1@sandi.netShelley Rannikko Standley Middle School srannikko@sandi.netSharon Strathman Jefferson Middle School sharon.strathman@oside.k12.ca.usTrudy Pachon Mark Twain High School NA(Ms.) Craig Kazaoka Palm Middle School NAWalter Solomon Preuss School wmsolomon@ucsd.edu

Lesson Plans

Walking in Sunshine

This lesson plan examines protection measures against UV rays. UV rays come from the sun and can damage the skin and eyes. The earth’s atmosphere protects us from the majority of UV rays from the sun. However, the atmosphere does not completely block UV rays and the condition of the ozone layer, especially in higher altitudes, allows more UV rays to reach the earth’s surface. In the Walking in Sunshine lesson plan, students use the Vernier sensor to record UVA readings. They test sunglasses, sunscreen, and cloth for their UV transmission properties. For all experiments, the students are to first take a control reading pointing the sensor straight up. This is a reading in which there is no protection from the UVA rays. Then one group tests the UV transmission through different sunglasses by placing sunglasses between the sensor and the sun. For the students testing the sunscreen, they have to put 5 different SPF samples of sunscreen on a clear piece of transparency and then test each one individually. The students testing the

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cloths place the UV sensor underneath the cloths, and record the readings as well as the texture/color of the cloths. Problems:

Accuracy of the readingo Students placing the sensor directly on materials, which result

in erroneous readings. It is important to leave some space in between the sensor and the cloth.

o Same transparency paper used to test different sunscreens, which leads to inaccurate conclusion. To solve this problem, smear all different sunscreen on same paper but in different corners, instead of repeating smearing/wiping off the sunscreen.

Iron Stomach- pHear Factor

This lesson plan focuses on the pH of solutions that we taste in everyday life. This lesson plan is a good way for students to understand pH and what makes substances as acidic or basic. At first three students are blindfolded and are given three samples of substances to taste and describe to the rest of the classroom. These students are blindfolded in order to get a non biased description of acids and bases. After this the students experiment using the Vernier sensors and record the pH readings of various test substances (e.g. hot sauce, Mylanta, soap, water, lemon juice, and corn starch). If the students get a reading below seven then the substance is acidic; if they get a reading above seven then the substance is basic.

Problems: Mold on the pH sensors

o Students should clean sensor thoroughly after substance measurement

Negative pH readings from sensoro Make sure calibration is correctly done. Some students “zero”

(a form of quick calibration) their instrument which should be avoided.

Solar Oven

This lesson plan, created by a former team, focused on the idea of solar energy. Sustainable energy sources, such as the sun, are becoming necessary in the global effort to protect the environment. Solar panels are a

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common source of solar energy, transforming the light from the sun into usable energy. It also reduces the need for coal, which generates about 54% of electricity for the U.S. and is the biggest cause of air pollution. The Solar Oven lesson plan allows students to harvest heat from the sun to cook smores. The students take an active role in building the solar oven. Materials include pizza boxes, black construction paper, clear plastic sheets, aluminum foil, and straws. The students use the LabQuest handheld device to record the temperature change inside the oven as they watch their treats heat up. The teacher engages the student further with related questions, for example, “What type of energy was harnessed from the sun?” and “What other types of energy does the sun give off?”

Problems Proper experimental conditions

o For a successful experiment, the weather needs to be sunny and experiment requires ample “cook time”

o For best result, sensor should be wrapped in black tape and held in between the two parts of the pizza box to absorb direct radiation and radiation reflected from the top and bottom of the pizza box.

No major problems occurred in this lesson plano Since the students have plenty of idle time while waiting for

their smores to melt, it may be useful to carry out a discussion for the students

How To Drown a Fish?

This lesson plan focuses on the relationship between temperature and the amount of dissolved oxygen in water. To relate to typical life examples, teachers explain why it is necessary to “bubble” the fish tank as well as maintaining it at a certain temperature range in order to retain enough oxygen for the fish to survive. Students obtain four cups of water at different temperature by adding different amounts of ice, to create a gradient of temperature from ice cold to room temperature. Students record these temperature readings by using the Vernier temperature probe. They bubble each cup and record/plot the oxygen readings immediately afterwards using the oxygen probe.

Before the experiment, the oxygen probes must be calibrated. The TIES students mainly help with the calibration, and the procedures are written clearly in the instruction manual in the oxygen probe box.

Problems

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Calibration can be time consumingo Ensure to have the helpers instead of the students perform the

calibration It is important that students record the oxygen reading one sample at

a timeo Students tend to bubble all samples simultaneously and bring

them back to their tables. This causes the temperatures to fall while measuring other heated samples, leading to inaccurate measurements.

6. Assignment Antarctica Game (Blayne)

Assignment Antarctica is a game in development designed and programmed by the San Diego Supercomputer Center (SDSC) headed by Jeff Sale. It is a 3-D multiplayer computer game where the students all connect to one server, control avatars, and roam around the vast landscape of Antarctica. Students can collaborate and work with each other to successfully complete various objectives, one of which involves collecting UV data from several key locations spread all around the continent. The game’s purpose is to promote environmental awareness of ultraviolet rays and ozone. Antarctica is the appropriate setting because more ultraviolet rays reach the earth due to the Antarctic ozone hole.

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Figure 8: Assignment Antarctica Home Page

The TIES team travels to the middle schools participating in ITEST and installs the game on the school computers. The team must document any bugs or performance issues and provide this information to Jeff Sale (jsale@sdsc.edu) to continually improve the game. Problems usually occur with older computers that can not properly run the game. The most updated version can be reasonably played on these older computers but still requires performance and bug documentation. This version of this game1 and the quick start information5 are provided below which each TIES member should review prior to each installation.

Currently the game is installed on the COSMOS computers, consisting of Apple MacBooks and Dell PCs. The game installs on the MacBooks in at most en minutes and multiplayer game play is relatively smooth. Because the Dells are of an older generation, they do not match the potentials of the MacBooks; however the game still runs relatively smoother compared to previous attempts. SDSC is modifying this game so that the game can run optimally on these older computers, so continuous feedback to Jeff Sale is necessary. One primary concern is to test the game play on the server; so far the MacBooks load the game in a few minutes with seldom server drops. More server testing needs to be performed on the Dell PCs.

So far the key issues occurring at the middle school game installations relate to district firewalls and networks. This, unfortunately, is something that both TIES and SDSC do not have any direct control over.4 http://visservices.sdsc.edu/projects/gamegrid/5 http://ties.ucsd.edu/ITEST/game/QuickStart.pdf

7. Preuss Science Olympiad (Zach)This quarter the TIES Middle School Environmental Education team

began working with the Preuss School’s Science Olympiad. Science Olympiad’s mission is to increase interest in STEM (Science, Technology, Engineering, and Mathematics), especially among female, minority, and other traditionally underserved students through exciting curriculum and challenging regional, state, and national competitions. By providing extracurricular enrichment, the Science Olympiad hopes to supplement and strengthen K-12 science education.

Mr. Nathan Burd (nateburd@gmail.com), a second-year middle school science teacher, manages Preuss’ Science Olympiad team. Last year he was overwhelmed by the time and energy required to support Preuss’ Division B and C teams (middle school and high school respectively). He hopes that in the coming school year TIES students will share the load and take

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responsibility for several events at each level. To maximize success, we should concentrate on the events that apply most to our individual majors, allowing us to provide our engineering skills.6

Mr. Burd and the Science Olympiad teams would like an optimum number of volunteers, with a bare minimum of 5 or 6 to be somewhat successful. It is key that we convince engineers in TIES to volunteer early in the quarter. One option would be to make Science Olympiad tutoring mandatory, with a certain number of hours required per team per week. We suggest that a MSEE member takes responsibility for coordinating tutoring efforts and communication with Mr. Burd. Ideally our tutors will observe the entire session and work with a ‘team’ of 4-8 middle or high school students on their event. According to Mr. Burd, tutors must provide a good deal of creative impetus and design work, as students will likely be unfamiliar with the engineering design process as well as common mechanical or electrical designs.

6 Events by applicable major (and division) Bioengineering

o Bio-Process (B)o Disease Detectives

(B&C)o Science Crime Busters

(B)o Cell Biology (C)o Forensics (C)o Health Science (C)

Chemical Engineeringo Environmental

Chemistry (B&C)o Chemistry Lab (C)

Structural/Civil Engineeringo Elevated Bridge (B&C)

Mechanical Engineeringo Physical Science Lab

(B)o Robo-Cross (B)o Scrambler (B)o Trajectory (B&C)o Egg-O-Naut (C)o Junkyard Challenge (C)o Technical Problem

Solving (C)o Write It Do It (C)

Aerospace Engineering:o Wright Stuff (B)o Egg-O-Naut (C)

8. Lesson Plan Additions

Introduction

Some students are visual learners in which they must physically see a conceptual application in order to understand the lesson. The TIES team seeks to create devices that individually encompass each lesson plan concept. The purpose is to apply key concepts to contraptions that would

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appeal to students and encourage them to pursue futures in science and engineering. This quarter the TIES team sought to include such devices into the pH and UV ray lesson plans.Food Batteries (Jose, Armita)

Inspired by pH lesson plans, the Food Battery experiment focuses on the use of an acidic food as a tool to transfer electrons. Batteries—also acidic—produce electricity by causing a chemical reaction inside the casing. Common batteries use two types of metal that can produce electricity. Since electric current is the movement of electrons from one atom to another in a conductor, in order for electricity to be produced in items that do not contain metals, the item must contain electrolytes. Electrolytes contain charged particles (ions) that can be used to generate the energy required to light a bulb. Food Batteries will hopefully be a fun way for students to visually see that a sample is acidic.

The goal was to replicate this experiment for the Iron Stomach – pHear Factor lesson plan such that students could observe a food’s acidity. Ideally, a luminous light bulb represented a highly acidic food substance and an unlit light bulb represented a more neutral or basic substance. The TIES team sought to replicate this by using small samples similar to the sample sizes that students used; we sought to set up a low powered lighting system where the teacher only needed to insert the probes into the food sample. However, two main concerns included whether the sample size affects current potential while experimenting and whether the most minimal energy consuming light bulb could illuminate using these small sample sizes.

A lemon and potato were used as the test samples. The experiment was conducted by sticking a piece of zinc metal and a piece of copper metal (zinc electrode and a copper electrode) into the lemon and connecting it to an LED bulb with copper wires. Two trials were attempted and each one was unsuccessful. From the first trial, we concluded that the power from an

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Figure 9: Basic Lemon Battery

individual lemon sample was insufficient to light the bulb. The second trial used a less demanding LED which also was unsuccessful due to insufficient power.

Suggestions include purchasing a pre-designed kit and using the components to test on various samples. TIES members can also measure current or voltage potential via multimeter and find equipment that operate with these values. However, teachers can choose to replicate this experiment if they both provide the necessary equipment/samples and perform the tedious setup.

UV Photography (Connie, Jeremy)

The TIES team explored this hobby to include into the Walking in Sunshine lesson plan. Originally, the team sought to fabricate a camera lens that photographs UV Ray skin damage in order to encourage UV protection. However, purchasing a lens unique for this was beyond our budget and designing this type of lens required technical skills surpassing ours. Thus, the team decided to create a lens universal to standard digital cameras that photographs pictures in the ultraviolet spectrum.

Ultraviolet photography is the process of taking photos using only the light from the UV spectrum. UV images shown in Neutrogena sunscreen ads in magazines are usually taken with UV cameras using Quartz lenses. Since our budget does not allow for the purchase of an expensive new camera, we used an alternative method to filter UV light from sunlight. An incandescent UV light bulb was purchased and broken into fragments. A fragment was then placed in front of a regular digital camera lens to filter all light except for UV light. We successfully took UV photographs that can be used in classrooms to demonstrate the existence of UV rays. The purpose behind this lens would be to show that although invisible to the eye, UV radiation does exist and is harmful to the skin.

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Figure 11: Current UV Figure 10: Light Filtration and UV Light

Potential problems include the type of UV light bulb being used. The current bulb is actually a fragment of a UV light tube instead of a bulb. This limits the maximum allowed space between camera lens and UV lens and requires manipulating the lens holder to photograph a “complete” picture. If one seeks to correct this by purchasing a UV light bulb, the lens holder must be machined via lathe to accommodate for this change.

9. Budget (Alan Toledo)This quarter we were bestowed a $500 budget. All expenses for this

quarter were allocated to assembling more hand held particulate matter sensors. Below is the budget for this quarter:

Budget ReportOriginal Budget $500

3 lithium ion batteries and 1 charger

-$45.20

LCD Screens/ADC -$78.19

Linksys Bluetooth -$43.24

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Figure 11: Stuart Collection’s “Bear” in UV light and Visible Light

Connectors -$9.00

Total (remaining) $324.37

10. AppendixAll drawings, models, and lesson plans from this quarter can be found on the MSEE page on the TIES website.

A-i. PM Sensor Parts

Listed as: Part Name – Part Number

PM Sensor – Shinyei PPD20VBasic STAMP – BS2e

Purchased from ParallaxADC - ADC0831 8-bit A/D converter DIPLCD - Parallax 2x16 Serial LCD (Non-Backlit)

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Purchased from Future Electronics3pin Connector – s3b-eh4pin Connector – s4b-eh

A-ii. Air Filter Lesson Plan

Particulate Matter Handheld Sensor Lesson Plan: Air Filter

Introduction:

We have all seen construction workers, doctors, firefighters, and people worried about swine flu wear protective masks over their faces to prevent the inhalation of dangerous foreign objects. This lab will measure the degree of protection that these filter masks provide as well as investigate which materials best filter the air we breathe.

Materials:

1. Handheld particulate matter sensor2. Incense3. Flour or chalk dust4. Filter mask, handkerchief, tissue, air filter paper

Procedure:

1. Turn on both particulate matter sensor and let it warm up.2. Record the base reading.3. Place the filter mask/handkerchief/tissue/paper on the underside of one

of the sensors, covering the air passage way.4. Light the incense5. Hold the sensor about two feet away from the burning incense. Make

sure that the sensor is held horizontally with the screen facing upwards and that both sides of the of the air passage way are unblocked.

6. Wait a few minutes for the incense to spread evenly in the area.7. Record the range of values that the sensor picks up for about 5-10

minutes.8. Now cut up the filter mask and tape it to both ends of the air passage

way.9. Again record the range of values that the sensor displays for 5-10

minutes.

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Image Source: http://www.pdclipart.org/displayimage.php?album=72&pos=222

10. Record the reading on each of the sensors and compare the results.

11. Repeat for each of the filtration materials and for chalk dust instead of incense.

Discussion Questions:

1. Which material worked the best at filtering the incense?2. Which material worked the best at filtering the flour?3. Does the rating on the filter mask or paper supported with the results

(assume incense particle size is 100-500 nm)?4. Bacteria range from around 200-2000 nm. Based on your results which

materials would most likely protect you from airborne bacteria?

A-iii. ADC Source Code

' {$STAMP BS2e} ' {$PBASIC 2.5} 'Program to convert analog sample to digital sample and output through LCD screen DIO CON 9 'Data in/out line on the stamp CLK CON 10 'Time communication between stamp and chipCS CON 11 'CS on ADC adc VAR WORD 'Data read from chip goes here conc VAR WORD 'actual concentration in part/Lcounter VAR BYTE avg VAR BYTE(20) TxPin CON 0 Baud19200 CON 32 HIGH TxPin

PAUSE 1000SEROUT TxPin, Baud19200, [22]PAUSE 500SEROUT TxPin, Baud19200, [12]PAUSE 500SEROUT TxPin, Baud19200, ["Turning on"]PAUSE 5000SEROUT TxPin, Baud19200, [12]PAUSE 500SEROUT TxPin, Baud19200, ["Sensor warm up", 13, "60 sec left"]

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counter = 60DO WHILE (counter > 0)PAUSE 1000IF counter = 10 THENSEROUT TxPin, Baud19200, [149," "] ENDIFcounter = counter - 1SEROUT TxPin, Baud19200, [148, DEC counter] LOOP

SEROUT TxPin, Baud19200, [12]PAUSE 500SEROUT TxPin, Baud19200, ["Ready to take readings"]PAUSE 1000

main:counter = 0

'Take 5 readings from ADCDO WHILE counter <= 20'GOSUB Setup_ADChipLOW CLK 'reset clock HIGH CS LOW CS'SHIFTOUT 1, CLK,MSBPOST, [1111\4] 'pull CS low to initiate conversion SHIFTIN DIO, CLK, MSBPOST, [adc\9] 'read 8 bit number from ADCavg(counter) = adccounter = counter + 1LOOP

'Calculate average adcadc = 0counter = 0DO WHILE counter <= 20adc = avg(counter) + adccounter = counter + 1LOOPadc = adc / 20

'Clear ScreenSEROUT TxPin, Baud19200, [12]

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'Calculate particles/LGOSUB Calculate_PperL

'Output concentration to screenIF adc <= 255 THENSEROUT TxPin, Baud19200, [DEC conc]SEROUT TxPin, Baud19200,[" particles/L"]DEBUG "Concentration: ", DEC conc, CRENDIFGOTO main

Setup_ADChip:

RETURN

'Input: adc'Output: concCalculate_PperL:IF adc <= 255 AND adc > 134 THENconc = adc * 232 - 16750ENDIFIF adc <= 134 AND adc >= 0 THENconc = adc * 107ENDIFRETURN

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