Transcript presentation

Otter Sensing
Kenji Nanto
Jared Lesicko
Miceal Rooney
Introduction
• Otters in Illinois
• Local otter population
• Difficulties in otter research
• Commercial availability
Sites where biologists from the Illinois Department of
Natural Resources detected evidence of the presence
of river otters (i.e., tracks, scats, or prey remains),
1999–2004.
Objectives
• Record ID, time, and temperature
• Three day battery life
• Weather proof durability
• Cost savings
Design Structure
Original Design
• Design and build own antenna and receiver
Antenna
Receiver Circuit
U2270B
Complications
• Antenna sensitivity/size
• Receiver unable to output sine wave
Coil 1 Oscillation
Simulated Envelope Detector
New Design
• Same overarching structure
• Uses three commercially available products from
Texas Instruments
– RI-ANT-G01E: antenna
– RI-RFM-007B: receiver/driver
– RI-CTL-MB2B: controller
Receiver
RFM-007B
Initializing Receiver
• Command using ASCII protocol from a
terminal emulator
– “V”: returns the device’s serial number
– “L”: puts device into Line Mode, standard
operation for our purposes
Initializing Receiver (cont.)
Response to “v”
Normal data stream in Line mode
Successful read
View of command terminal
RS232 to TTL
MAX-232
RS232 Shifter SMD
RS-232 to TTL
• RS-232 logic levels
– 1: 𝑉 < −3 𝑉𝑜𝑙𝑡𝑠
– 0: 𝑉 > +3 𝑉𝑜𝑙𝑡𝑠
• TTL logic levels
– 1: 0 < 𝑉 < 0.8 𝑉𝑜𝑙𝑡𝑠
– 0: 2.2 < 𝑉 < 5 𝑉𝑜𝑙𝑡𝑠
00 0
00
11
00
11
1
00 0
1
ASCII “L” in RS-232
ASCII “L” in TTL
Temperature Sensor
• Diode outputs analog voltage based on
temperature
– 𝑇𝑒𝑚𝑝𝑒𝑟𝑎𝑡𝑢𝑟𝑒 [°𝐶] =
𝑉𝑜𝑢𝑡 𝑚𝑉 −500𝑚𝑉
10𝑚𝑉/℃
– 𝑉𝑜𝑙𝑡𝑎𝑔𝑒 𝑎𝑡 𝑃𝑖𝑛 𝑚𝑉 =
𝐴𝐷𝐶 𝑅𝑒𝑎𝑑𝑖𝑛𝑔
1024
× 3300𝑚𝑉
Control Unit
• Arduino Mega 2560 + Adafruit Data Logging Shield
• Powered By Car Battery
• Serial Input
• Voltage Reading from Temperature Sensor
• DS1307 – Real Time (Low Power Backup - 12mm 3V lithium coin cell)
Control Unit (cont.)
Power Supply
• Main source: 75 Ah car battery
– Maximum Required capacity:
𝑇𝑜𝑡𝑎𝑙 𝑃𝑜𝑤𝑒𝑟 𝑈𝑠𝑒𝑑 𝑊 × 72 ℎ𝑟𝑠
12𝑉
(𝑀𝑖𝑐𝑟𝑜𝑐𝑜𝑛𝑡𝑟𝑜𝑙𝑙𝑒𝑟 + 𝑇𝑒𝑚𝑝 𝑆𝑒𝑛𝑠𝑜𝑟 + 𝑅𝑒𝑐𝑒𝑖𝑣𝑒𝑟) × 72ℎ𝑟𝑠
=
12𝑉
−4
(2.4𝑊 + 1.65 × 10 𝑊 + 3.6𝑊) × 72ℎ𝑟𝑠
=
= 𝟑𝟔𝑨𝒉
12𝑉
12𝑉 𝐵𝑎𝑡𝑡𝑒𝑟𝑦 𝑅𝑎𝑡𝑖𝑛𝑔 𝐴ℎ =
Voltage Regulator
• Required for receiver and microcontroller
• Allowed 𝑉𝑟𝑚𝑠 ≤ 50𝑚𝑉
𝑀𝑎𝑥 𝐶𝑢𝑟𝑟𝑒𝑛𝑡 𝐷𝑟𝑎𝑤 = 3𝐴
𝑉𝑜𝑙𝑡𝑎𝑔𝑒 𝐷𝑟𝑜𝑝 𝑎𝑡 3𝐴 = 0.5𝑉
𝑉𝑟𝑚𝑠 = 0.5𝑚𝑉
Power Supply (cont.)
• Logic converter: 2 standard 9V batteries
– Required capacity:
𝑇𝑜𝑡𝑎𝑙 𝑃𝑜𝑤𝑒𝑟 𝑈𝑠𝑒𝑑 𝑊 × 72 ℎ𝑟𝑠
9𝑉
𝑀𝐴𝑋232 𝑃𝑜𝑤𝑒𝑟 × 72ℎ𝑟𝑠 9 [𝑚𝑊] × 72ℎ𝑟𝑠
=
=
= 𝟕𝟐𝒎𝑨𝒉
9𝑉
9𝑉
9𝑉 𝐵𝑎𝑡𝑡𝑒𝑟𝑦 𝑅𝑎𝑡𝑖𝑛𝑔 𝐴ℎ =
Current Status
The Good
The “To Be Fixed”
• Battery life exceeds
requirements
• Data storage difficulties
• Sensing range
• Data transfer
• Housing in progress
Future Work
• Cleaning up circuitry
• Expansion using multiplexer and additional
antennas
• Duplication of system
Ethical Considerations
• Low frequency RFID requires no license
• Avoid harming and interfering with wildlife
• Security Concerns
Acknowledgements
Prairie Research Institute
Samantha Carpenter
Professor Carney
Mustafa Mir
Professor Bernhard
ECE Parts and Machine Shops
Questions