Final Presentation - Drexel Wireless Systems Laboratory - Drexel ...

ECE Team 01
Justin Arling
Kyle O'Connor
Mike Mercieca
Advisors
Dr. Kapil Dandekar
Dr. Timothy Kurzweg

Project Background
-Hunting Park
• The Hunting Park
community is concerned
with the amount of industrial
activity in their area
• They wanted to know how
their air quality compares to
the rest of the city and
nation
• A team was formed with the
Clean Air Council, Chemical
Heritage Foundation, and
others to investigate
2

Project Background
• Philadelphia Air Management Service (AMS)
o Monitors the air quality at various locations
throughout Philadelphia and enforces city, state, and
federal air quality standards
o Weighing Filter Monitor
• $100 - $200 per measurement
• $25,000 - $50,000 to set up a weighing facility
• Data takes 2 weeks to process
o Continuous Filter Monitor (Met-One BAM-1020)
• Cannot be used as final judge of air quality
• $14,300 per device
Ulva, M. et al, “Preliminary Screening System for Ambient Air Quality in Southeast Philadelphia – ECE-19,” Drexel University
Electrical and Computer Engineering Senior Design, 2009
4

Project Background
• The Clean Air Council of Philadelphia (CAC) sponsored
this project to design Air Quality Monitors with the following
specifications:
o Low cost (about $500 per node)
o Low-profile
o Easily Maintainable
5

Last Year's Work
• System for monitoring
particulate matter has been
developed
o Low in Cost
o Small in Size
o Not easy to use
• Technical Components
o Dylos DC1100 Pro Laser
Particle Counter
o XBee Wireless Sensor
Network
o Base Station computer
6

Key Improvements
• Increased size of the network
• Extended overall battery life for each node
• Adjusted network configurations for easier
deployments
• Improved upon the usability of the system
with the following features:
o Intuitive deployment interface
o Automated and continuous data processing
o Real-time visualization of results via the
internet
• Continued validation of data accuracy
7

System Components
8

Work Completed
-Node Construction
9

Node Construction
Node Hardware
• Added a total of 7 new nodes to the system
o Built 3 of the nodes ourselves
o Mentored North Penn High School students in
building the other 4 as part of the EPICS program
10

Work Completed
-Power
11

Power
• Battery life of the older system: ~6 Days
• Parallel battery solution
o Cost - $60 extra per node
o Subject to current flowing from one battery
to the other
•Schottky Diode
•Stops current from flowing from one to
the other
•Low Forward Voltage Drop
12

Power
-Battery Life Comparison
Battery Type
Impact Universal Li-
Ion Rechargeable
Battery (last year)
Capacity Life for
Single
Battery
(days)
Life for
Parallel
Batteries
(days)
Improvement
(%)
8000 mAh 5.2 9.15 75.15
Ultralast Universal
Li-Ion Portable DVD
Replacement Battery
(this year)
5400 mAh 3.41 6.41 88.06
13

Work Completed
-Networking
14

Networking
• Previous issues:
o System range was limited to approximately
150 meters when line-of-sight
o Can take several cycles for a new node to
synchronize with the network's sleep
schedule
• Improvements:
o Implementation of firmware upgrade allows
network hopping and faster sync times
15

Network Hopping
16

Network Hopping
17

Network Hopping
18

Network Hopping
19

Network Hopping
20

Network Hopping
21

Network Hopping
22

Network Hopping
23

Network Hopping
24

Networking
• Previous firmware required all nodes,
including the base station, to sleep
• New firmware allows base station to
remain awake at all times
o Typical sync time is only a few seconds
•Node is turned on and broadcasts signal
•Base station 'sees' node and sends
sleep schedule
•Node begins following schedule
25

Data Collection
&
Visualization
Demonstration
Backup Slides
26

Data Validation
• Humidity Correction Factor
o F = O x H x C
• F - Final Concentration
• O - Output Concentration
• H - Relative Humidity
• C - Correction Factor
• Data was collected in a side-byside
deployment with AMS
monitors for 33 days
o 3,177 usable data points
Lee, J. et al., “Seasonal variations of particle size distributions of PAHs at Seoul, South Korea,” Air Quality Atmospheric Health,
vol. 1, pp. 57-68, 2008.
Tittarelli, T. et al., “Estimation of particle mass concentration in ambient air using a particle counter,” Atmospheric Environment, vol.
42, pp. 8543-8548, 2008.
27

Data Validation
• Correction factors used last year have been updated in
order to account for the new data
Before Correction:
Average concentration
measured 4.98 μg/m 3 (95%
CI 4.71 to 5.24) lower than
measured by Air
Management Services
After Correction:
Average concentration
measured 0.63 μg/m 3 (95%
CI 0.4 to 0.87) lower than
measured by Air
Management Services
28

Data Validation
*Supplemental documentation has been created for a more
detailed discussion on the efforts and results associated with
data validation.
29

Differences from Last Year
Previous Design
New Design
Number of Nodes 5 12
Power (Battery Life) 6 Days >9 Days
Power Consumption Single Battery Dual-Batteries
Network Technology XBee Improved XBee
Network Range
~150 Meters
Up to ~300 Meters
(single hop)
Data Processing
Data Viewing
Manual Process
Excel Output
at Base Station
Automatic &
Continuous
-Mapped Results
-Streaming Data
-Web Based View
30

Engineering Projects in
Community Service (EPICS)
• Worked with students from North Penn High
*Financially supported through IEEE New Initiatives, EPICS in High Schools
31

EPICS
• Worked together to build
an additional four nodes
• Constructed PCBs for the
power circuitry
• Developed a plan to
monitor air quality in
school bus loading zones
32

Timeline
• All deadlines for deliverables were met as scheduled
• Final term milestones were as follows:
o Completed software and data visualization
o Improved data correction factors based on AMS
Deployment
o Deployments in Norris Square and Hunting Park
33

Project Deliverables
34

Budget
Over Budget by roughly $130 - 3.56%
35

Future Work
• Continued data validation to capture yearround
environmental scenarios
• Implementation of a low-cost GPS solution
• Improving air flow to particle counter
• Adding a localized humidity sensor
• Monitoring the battery power remotely
36

Questions
Justin Arling
Kyle O'Connor
Michael Mercieca
- ja98@drexel.edu
- ko43@drexel.edu
- mm533@drexel.edu
We would like to acknowledge the following groups
for their time, effort, and support.
Philadelphia Clean Air Council
Air Management Services
Chemical Heritage Foundation
Hunting Park Stakeholders Group
37

Backup Slides
38

Humidity Correction Factor
39

Data Validation Numbers
40

Power
• 2 Schottky Diodes in Parallel
o Voltage drop of only 0.27 V
o Dissipates heat buildup
41

Constraints
• Economic
o Cost Effective
• $500 per node
o Parts must be cost effective
• Low cost batteries
• Pay as you go Broadband service
• Upgrades were hand created voltage regulator
o Quality did not suffer as a result
• Manufacturability
o Enclosures low-profile and weatherproof
o Relative simplicity of the system
• Allows for future build outs to be successful
42

Constraints
• Sustainability
o Designed for a long lifespan
• Parts are interchangeable
o Increased lifespan of power
• Putting 2 batteries in parallel does this
• Schottkey diodes dissipate heat and reduce wear on
system
• Environmental
o When deploying the systems, buildings, trees, and
weather limit the range
o Nodes need to be hung with vents facing downward
• Ethical Health and Safety
o Goal to improve the public's overall environment
o Project driven by this, not constrained
o Clean Air Council must carefully consider what to do with
the information this project gives
43

Constraints
• Social
o Public has to be supportive and helpful
• This allows for a much larger deployment area
o Without public help, system would be placed in unsafe
area that could lead to theft and tampering
• Political
o Working with and within the Clean Air Council and AMS's
boundaries is a must
o The Clean Air Council's requirements were a driving force
to the project
o Approval from AMS to hang a node at their facility was
required to continue with data validation
o When deploying the system, it needed to be explicitly
stated that the system was a preliminary screening and
not the final authority on the air quality in the area
44

Industrial Budget
45

Drexel Monitor vs Industrial Monitors
AMS Weighing Filter System
Met-One BAM-1020
Ulva, M. et al, “Preliminary Screening System for Ambient Air Quality
in Southeast Philadelphia – ECE-19,” Drexel University Electrical and
Computer Engineering Senior Design, 2009
46

Fall - Proposed
47

Fall - Actual
48

Winter -
Proposed
49

Winter -
Actual
50

Spring -
Proposed
51

Spring -
Actual
52

Data Validation
65