Get documents about "project1 presentation
Document Sample
Bird Accelerometer II:
Caw of the Wild
● Introduction and Motivation
● The Original Design
– Acceleration & Theory
– Low-cost, high-reliability RF link
– Data Acquisition Software
● The Real Design
– RF Link Changes
– Software Suite
– Critical Timing Loop
● Test & Verification
– GooseFly visualization
– Range & Power
● Further Suggestions & The Next Generation
Introducton & Motivation
● Seiler, Pant, & Hedrick. A Systems
Interpretation for Observations of
Bird Flying-V Formations. J. Theo.
Biology, 221, pp279-287.
● Want to see motion/phase relationships between
birds flying in a flock
● What do the biologists need?
– A flock of geese outfitted with accelerometer boards.
– A receiver + automatic log of all birds' flight data.
– An indicator when birds fly near detector so they can
record the flock formation (photographically).
Original Design
● Goal: Prototype of a complete, automatic,
wireless Accelerometer-Board to PC-based-
Storage for one bird.
● Accelerometer/Transmitter Board
● Receiver Board
● Custom Data Acquisition Software on PC
● Error-Correcting Wireless Protocol
● Serial RF Link, ~30KBaud
● Smart Power Consumption
ADXL202 Bird Board 1-Bird Receiver (At Base Station)
(X,Y)
Sel MAX232
RFPIC MAX1470
ADXL202 8-1 ( C/ PIC16F877
Data RS232
(Y,Z) MUX ASK Tx) (ASK Rx)
Transceiver
ADXL202
(Z,X) Lightweight
Battery
Host PC (Win32) Serial Port
Block Diagram: Permanent Storage
Time/bird-coded data
Original Design
GooseChase 1.0
files with interleaved
Error-Correction Processing &
error stats &
Data Acquisition Software
timestamping
Realtime GooseChase
Named-Pipe Server
GooseBar
Calibration/Test
Program
GooseFly Other 3rd-Party
Flight-Path Utilties/Analysis
Visualization / Packages.
Demonstration Receive & Process
Calibration File Program bird data in realtime.
ADXL202 Bird Board 1-Bird Receiver (At Base Station)
(X,Y)
Sel MAX232
RFPIC MAX1470
ADXL202 8-1 ( C/ PIC16F877
Data RS232
(Y,Z) MUX ASK Tx) (ASK Rx)
Transceiver
ADXL202
(Z,X) Lightweight
Battery
Host PC (Win32) Serial Port
Sensor/
Transmitter Permanent Storage
Time/bird-coded data
files with interleaved
GooseChase 1.0
Error-Correction Processing &
error stats &
Board timestamping
Data Acquisition Software
Realtime GooseChase
Named-Pipe Server
GooseBar
Calibration/Test
Program
GooseFly Other 3rd-Party
Flight-Path Utilties/Analysis
Visualization / Packages.
Demonstration Receive & Process
Calibration File Program bird data in realtime.
ADXL202
(X,Y)
Bird Board Transmitter Board
Sel
RFPIC
ADXL202 8-1 ( C/
MUX Data
(Y,Z) ASK Tx)
ADXL202
(Z,X) Lightweight
Battery
● Transmitter Board (similar to previous group's)
– Analog Devices ADXL202 2-Axis Accelerometers
– RFPIC12F675K Integrated μC + ASK TX
– Added a MUX to use all 6 accel. measurements.
– Use of potable ?Lithium? Battery
Accelerometer Loop Timing
● Tradeoffs
– PWM Period: Longer => Better Measurements
– PWM Period: Shorter=> Faster Loop/Sample Rate
● Transmission of 14 bytes (encoded as 28) takes
9msec
● Reading 6 ADX PWM signals at 2.5-5ms apiece
takes 15-30msec
● Total loop time: 24-39msec
● 6-channel Sample Rate of 25-39Hz
● Average Rate: 29Hz
● PWM measurements are on the order of 7-8 bits
ADXL202 Bird Board 1-Bird Receiver (At Base Station)
(X,Y)
Sel MAX232
RFPIC MAX1470
ADXL202 8-1 ( C/ PIC16F877
Data RS232
(Y,Z) MUX ASK Tx) (ASK Rx)
Transceiver
ADXL202
(Z,X) Lightweight
Battery
Host PC (Win32) Serial Port
Block Diagram: Permanent Storage
Time/bird-coded data
Original Design
GooseChase 1.0
files with interleaved
Error-Correction Processing &
error stats &
Data Acquisition Software
timestamping
Realtime GooseChase
Named-Pipe Server
GooseBar
Calibration/Test
Program
GooseFly Other 3rd-Party
Flight-Path Utilties/Analysis
Visualization / Packages.
Demonstration Receive & Process
Calibration File Program bird data in realtime.
1-Bird Receiver (At Base Station)
Receiver Hardware
LINX MAX232
PIC16F877 RS232
HP3
RX Transceiver
● Receiver Board
– Complementary ASK RX Chip: MAX1470
– PIC16F877 to receive, rate-convert, and pass to host
– MAX232 RS-232 Interface for Serial comm. w/ PC
ADXL202 Bird Board 1-Bird Receiver (At Base Station)
(X,Y)
Sel MAX232
RFPIC MAX1470
ADXL202 8-1 ( C/ PIC16F877
Data RS232
(Y,Z) MUX ASK Tx) (ASK Rx)
Transceiver
ADXL202
(Z,X) Lightweight
Battery
Host PC (Win32) Serial Port
Portable Power Permanent Storage
Time/bird-coded data
files with interleaved
GooseChase 1.0
Error-Correction Processing &
error stats &
Data Acquisition Software
timestamping
Realtime GooseChase
Named-Pipe Server
GooseBar
Calibration/Test
Program
GooseFly Other 3rd-Party
Flight-Path Utilties/Analysis
Visualization / Packages.
Demonstration Receive & Process
Calibration File Program bird data in realtime.
Power
(Measured Value)
● Test Setup: 6V Battery
● regulated down to 3.3V
● Normally: A 3V Li battery will suffice
● Measurement: 21mA with the Linx transmitter
● Theoretical value achievable with power
management
Transmitter
● 315 Mhz ASK
Waveform:
Transmitter
Frequency Domain:
Final Transmitter
● Uses Linx Chip due to ASK receiver problems
● FSK modulation just above 900MHz
ADXL202 Bird Board 1-Bird Receiver (At Base Station)
(X,Y)
Sel MAX232
RFPIC MAX1470
ADXL202 8-1 ( C/ PIC16F877
Data RS232
(Y,Z) MUX ASK Tx) (ASK Rx)
Transceiver
ADXL202
(Z,X) Lightweight
Battery
Host PC (Win32) Serial Port
RF Physical Permanent Storage
Time/bird-coded data
Layer files with interleaved
error stats &
timestamping
GooseChase 1.0
Error-Correction Processing &
Data Acquisition Software
Realtime GooseChase
Named-Pipe Server
GooseBar
Calibration/Test
Program
GooseFly Other 3rd-Party
Flight-Path Utilties/Analysis
Visualization / Packages.
Demonstration Receive & Process
Calibration File Program bird data in realtime.
MAX1470 Receiver Problems
● Difficulties with testing
– Difficulty reading signals at receiver pins
● Oscillator wire picks up the transmitter signal without
physical contact to anything
● Not sure if a real signal at the pin or just interference
● Cannot test RF with equipment in the lab
● Time constraint
– Obtaining adapter boards for SMT parts late
– First attempt for transmitter on a protoboard (bad idea!)
● General lack of RF expertise
ADXL202 Bird Board 1-Bird Receiver (At Base Station)
(X,Y)
Sel MAX232
RFPIC LINX LINX
ADXL202 8-1 PIC16F877
Data (W/Out HP3 HP3 RS232
(Y,Z) MUX
RF) TX RX Transceiver
ADXL202
Lightweight
(Z,X)
Battery
Host PC (Win32) Serial Port
Alternate RF Permanent Storage
Physical Layer Time/bird-coded data
files with interleaved
error stats &
timestamping
GooseChase 1.0
Error-Correction Processing &
Data Acquisition Software
Realtime GooseChase
Named-Pipe Server
GooseBar
Calibration/Test
Program
GooseFly Other 3rd-Party
Flight-Path Utilties/Analysis
Visualization / Packages.
Demonstration Receive & Process
Calibration File Program bird data in realtime.
ADXL202 Bird Board 1-Bird Receiver (At Base Station)
(X,Y)
Sel MAX232
RFPIC MAX1470
ADXL202 8-1 ( C/ PIC16F877
Data RS232
(Y,Z) MUX ASK Tx) (ASK Rx)
Transceiver
ADXL202
(Z,X) Lightweight
Battery
Host PC (Win32) Serial Port
Host PC Permanent Storage
Time/bird-coded data
Software Suite files with interleaved
error stats &
timestamping
GooseChase 1.0
Error-Correction Processing &
Data Acquisition Software
Realtime GooseChase
Named-Pipe Server
GooseBar
Calibration/Test
Program
GooseFly Other 3rd-Party
Flight-Path Utilties/Analysis
Visualization / Packages.
Demonstration Receive & Process
Calibration File Program bird data in realtime.
GooseChase Data Acquisition
Decodes/corrects data
and writes to files with
a timestamp in the
filename. It also keeps
track of the number of
correctable and
uncorrectable errors
and keeps statistical
information on the
quality of the packets.
GooseChase Files
All the GooseChase files
from the start of the
semester. Each file name
has the bird number and
current date/time to the
millisecond. This history
will allow the researchers
to keep a good record of
all the historical bird
information.
GooseBar Monitor & Calibration
This obtains the current data reading
and shows the length of the respective
PWM channels.
Because different ADX chips have different
PWM lengths for the same orientation,
calibration is necessary.
Holding the board in all the cardinal axis and saving the PWM
output to a file serves as a calibration file for the board. Assume
linear response from -1g to +1g.
Once the data has been normalized and shifted so all the chips are
reading on the same scale, trigonometry can be used to derive
pitch and roll information.
GooseFly Visualization
Bird data is fed through
named pipes into a
computer graphics program
that gives a visual feel to
the project. This also serves
as the ultimate test to show
the validity of our data. The
calibration file GooseBar
wrote is used in getting a
correctly oriented bird on
screen.
Video
Cost Estimate
Final Costs Quantity Cost/Unit Cost
Transmitter:
PIC12F675k 1 $4.00 $4.00
ADXL202 3 $15.00 $45.00
Linx HP3 Transmitter 1 $30.00 $30.00
Battery (Li, 1Ah, 3.6V) 1 $3.00 $3.00
Other 1 1 $1.00
Board Production 1 $5.00 $5.00
Total: $88.00 $58.00 Without the Linx Chip
Receiver:
MAX232 1 $1.00 $1.00
PIC16F877 1 $8.00 $8.00
Linx HP3 Receiver 1 $14.00 $14.00
Or MAX1470 1 $3.50 $3.50
Other 1 $1.00 $1.00
Total: $24.00 $13.50 Without the Linx Chip
Possible Improvements
● Smart Power Algorithm
● Surface Mount PCB
● Triple-axis Accel / Gyro
● Compass for Heading
Questions?
Related docs
Other docs by HC121005102213
