Project B.I.N.S.
Senior Design Project:
FPR
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Introductions, a Final Encore
Professor Tessier
Advisor
Jim Doty
EE
Sensor Subsystem
Belief Gratini
CE
Server Subsystem
Marcus Mei
EE
Power Subsystem
Frank Zhang
CE
Firmware
Subsystem
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• Overflow of trash is an environmental and health hazard for parks, cities, and
schools.
• Waste management resources are limited, so we can find ways to better optimize
them.
Problem Statement
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Barrel Integrated Networking System
As a real time, automated, trash-sensing system
B.I.N.S. will:
• Monitor trash levels
• Provide notifications on fill level
• Be self sustaining
Learn more at: http://www.ecs.umass.edu/sdp/sdp21/team01/
Our Solution: Project B.I.N.S.
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Our Solution: The Final Prototype
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Solar panel bracket mounted
on exterior of trash can.
View looking in from where the trash gets thrown in. Screenshot of the where the sensor data goes.
Our Solution: The Final Prototype
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Assembled PCB fitted into enclosure without the roof.
Fully assembled outside of trash can.
The Finalized Block Diagram
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Visualizing the Block Diagram within our PCB
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Visualizing the Block Diagram within our PCB
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• Deep Sleep Mode
• Reduces power consumption
• Turns off everything except RTC, which can be used for storage
• Maximum time of about 70 minutes
• Cycle time of 10 seconds for demo, 15 minutes for practical use
Firmware Updates
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Backend Application
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Sensor
API
Schema
Application
1. Capable of operating from 0°C to 50°C.
2. Capable of operating without sunlight for 1 week.
3. Placement of unit will not impede use of trash bin.
4. Ultrasonic sensor capable of measuring up to 28 in.
5. Sensor capable of making measurement within 10 seconds, accurate to 2 in.
6. Connect to a wifi router within 100 feet obstructed.
7. Weather resistant housing for sensor unit.
8. Should not exceed $100 per unit.
Checklist of System Specifications
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Capable of operating without sunlight for 1 week.
Status: Met
Actual time: 8+ hours continuous running
= 10 days before full discharge
• Tested by having the sensor constantly connected and
outputting to AWS until the connection was lost.
System Lifetime Specification
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Testing setup where the sensor just sat
and took measurements continuously.
Solar Charge Time
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Test setup the PCBA charge controller
circuitry in the engineering quad.
8.4 V
314 min
Sunny Too cloudy
● Extrapolation is linear because of the charge controller operation
• Addressing a major CDR Concern
• Returned to an idea from the post-PDR period (with approval from coordinators)
The Ultrasonic Sensor
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Commercial sensor module used
in final prototype
Commercial sensor module slotted in the system
enclosure and the PCBA components it replaces
(boxed)
• Gather data on sensor
performance at varying target
distances
• Tested with actual trash items
in a trash barrel
• Sensor is allowed to loop
measurements for 2 minutes
before moving to the next
increment
Sensor System Testing
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The “patent pending” demo trash
tool used in testing
The sensor in its enclosure under
test
Sensor Specifications
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Commercial sensor module test results plotted across out
specified operating range (tens of thousands of samples)
Takeaways
• Average measurement time of 15 ms
• 99% Confidence interval [15.41, 15.62]
• At least 99.34% accurate to 2 inches of
expected
• These trends continue up to our specified
distance of 28 inches
Sensor capable of making measurement within 10 seconds, accurate to 2 in. Status: Met
Ultrasonic sensor capable of measuring up to 28 in.
Status: Met
Connection to WiFi Router
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● Gathered data on WiFi connectivity times from
varying distances
○ Using Mobile hotspot
○ Connect to WiFi and output time to AWS,
go into Deep Sleep, repeat
○ Collected 28 measurements
○ Average time to connect: 9.46 sec
Testing the connection time to a WiFi router when standing
100 feet away with an obstructed view
Capable of connecting to WiFi router
within 100 feet obstructed
Status: Met
Mobile hotspot
Ultrasonic
sensor
Distance: 100 feet
• 95% Confidence Level
• Margin of error = 1.31
• 95% Confidence Interval [8.14, 10.77]
• Can say with 95% confidence that we can connect to WiFi from 100 feet away
with an obstructed view in an average time of between 8.14 and 10.77 sec
Analyzing WiFi Connectivity Data
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Placement of unit will not impede use of trash bin.
Status: Met
• The sensor sits underneath and offset from opening.
Physical Specifications
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Weather resistant housing for sensor unit.
Status: Met
• The housing piece is plastic with a rubber seal for
where the solar panels plug in.
Final Unit Cost - Under $100
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Per Unit Price
2 x 3.7V Lithium Ion Batteries 500 mAh $15.90
2 x 2.5W Solar Panels (w/ Connector) $12.99 ($2.18)
Dual Cell Charge Controller (BQ2057) $2.55
4 x Schottky Diode (MBRA210LT3G) $1.52
3 x Voltage Regulators $3.56
4 x Transistors (3 MOSFET, 1 BJT) $0.93
Thermistor NTCLE100E3103JB $0.69
HC-SR04 Ultrasonic Distance Sensor $3.95
ESP-Wroom-2 (WiFi MCU module) $2.60
Estimate of PCB and Res/Caps $3.50
Per Unit Cost: $50.37
Should not exceed $100 per unit. Status:
Met
Demonstration in Progress:
Please turn your attention to the shared screen
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Questions? Comments?
Concerns?
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Additional Resources as
Needed
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Capable of operating from 0°C to 50°C. Status: Partially Met
Why:
• Charge controller circuit design is informed by this temperature specification and
ensures safe charging and operation of the unit from the batteries’ point of view
But:
• While the ultrasonic sensor module used is rated to operate across the entire range,
its accuracy cannot be guaranteed due to fluctuations in the speed of sound.
Temperature Specification
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Comparison of CDR Sensor to New Module
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Hardware:
• 2 x 3.7V Lithium Ion Batteries 500 mAh
• 2 x ALLPOWERS 2.5W Solar Panels
• 4 x Schottky Diodes (MBRA210LT3G)
• BQ2057 Dual Cell Charge Controller
• LM7805 5V Regulator
• TLM760M33 3.3V Regulator
• TPS5602 Adj. Switching Regulator
• RQ5E5025 P-channel MOSFET
• NTC 10k Thermistor
• HC-SR04 Ultrasonic Distance Sensor
• ESP8266 Huzzah Module (ESP-WROOM-2)
List of Hardware and Software
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Software:
● Arduino IDE
● Amazon Web Services (AWS)
● AWS Amplify
● AWS Dynamo
● AWS Synch
● Agilent Data Logger
● Onshape
Custom PCB Schematic
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Custom PCB - Layout
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ESP-Wroom-2
module for reference
Pictured is a model of our PCB from Altium
Designer, with designators to breakdown how
each stage of our block diagram fit on board
Section no longer used
