Critical Design Review
Capstone Lab 2009
Steven Sorenson
Greg Smith
Anand Suchak
Kristen Aragon
John Strueber
Overview
Core Functionality
System Breakdown
Risks
Budget
Division of Labor
Schedule
Questions
Kristen
We will be creating an interface for a mp3
player to allow for button-less control.
We will also be creating a perfomance data
collector that will keep track of position, heart
rate, g-forces and accidents.
This would be useful in situations where you
cannot easily access the mp3 player and it will
also provide the user with feedback from the
day.
Kristen
Song Control
Previous/Next track
Play/Pause
Volume Up/Down
Wireless Control
Monitoring
GPS
Heart Rate Monitor
Accelerometers
Pressure Sensors
Kristen
John
Using two ATTiny µcs
One operating as Master of I2C, other as Slave
On-chip UARTs dedicated to Bluetooth and GPS
modules
Need one more UART for SD card memory
Using Phillips SC16IS740 bridge connected to I2C
bus
EFI and ECG sensors will interface over ADC
John
Steven
Steven
Steven
SiRF Star III chipset
Antenna Gain: 3.5dB
Low power:3.3 V at 75 mA
Outputs NMEA sentences
over serial connection
Master µc will parse
NMEA to extract location
& time data
Anand
BlueSMiRF Gold Modem
Works for TX/RX from 9600 to
115200bps
Specifications
Power Consumption: 25mA
Operating Voltage:3.3V-6V
Frequency: 2.4-2.524GHz
Serial Communication:2400-115200bps
Anand
Anand
LG Rumor II
Google G1 Android
Both support AVRCP Bluetooth protocol
Anand
Kristen
Kristen
Single supply CMOS
operational Amplifier
Low Offset Voltage 5µV
(max)
Zero Drift 0.05µV/°C (max)
Single-Supply Operation
MicroSize Packaging
Kristen
Micro-Power, Zero-Drift,
Rail-to-Rail Out
Instrumentation Amplifier
Low Offset Voltage 25µV
(max)
Low Drift 0.1µV/°C
Low Noise 50nV/
Built in RFI filtered inputs
Micro Power
Microsize
Kristen
Proximity detection by measuring capacitance
MC33941 generates a high purity e-field by
emitting a sine wave at a low frequency
(125kHz)
Measuring attenuations suffered by this field
When an object is brought close to an electrode
an electric path is formed
This produces a change in e-field current
Sensor measures the AC impedance of the
generated e-field and outputs a DC voltage
External microcontroller then processes the
signal
Greg
Greg
Greg
1.03
1.01
0.99
0.97
E1 Norm
E2 Norm
0.95
E3 Norm
E4 Norm
0.93
0.91
0.89
0.87
0
1
2
3
4
5
6
7
8
9
10
Greg
0.1
0.3
0.5833333
0.85
1.066667
1.333333
1.583333
1.883333
2.083333
2.35
2.633333
2.916667
3.1
3.383333
3.666667
3.85
4.133333
4.383333
4.7
4.883333
5.166667
5.45
5.633333
5.916667
6.2
6.483333
6.666667
6.95
7.2
7.416667
7.7
7.983333
8.266667
8.45
8.733333
9.016667
9.3
9.483333
9.766667
10.01667
1.11
1.06
1.01
0.96
0.91
0.86
0.81
Greg
E1 Norm
E2 Norm
E3 Norm
E4 Norm
1.035
1.015
E1 Norm
0.995
E2 Norm
E3 Norm
E4 Norm
0.975
0.955
0.935
0
1
2
3
4
5
6
7
8
9
10
Greg
Time (s)
0.3
0.4833333
0.7666667
1.05
1.233333
1.516667
1.766667
2.083333
2.266667
2.55
2.833333
3.016667
3.3
3.583333
3.866667
4.05
4.333333
4.583333
4.8
5.083333
5.366667
5.65
5.833333
6.116667
6.4
6.583333
6.866667
7.15
7.4
7.616667
7.9
8.183333
8.466667
8.65
8.933333
9.216667
9.4
9.683333
9.966667
1.03
1.02
1.01
1
0.99
E1 Norm
E2 Norm
0.98
E3 Norm
E4 Norm
0.97
0.96
0.95
Greg
1.05
1.03
1.01
0.99
0.97
E1 Norm
E2 Norm
0.95
E3 Norm
0.93
E4 Norm
0.91
0.89
0.87
0.85
0
1
2
3
4
5
6
7
8
9
10
Greg
1.09
1.04
0.99
E1 Norm
E2 Norm
0.94
E3 Norm
E4 Norm
0.89
0.84
0.79
0
2
4
6
8
10
12
Greg
Electromagnetic fields caused by surroundings
Weather/Shock Proofing
Inadequate resolution of sensing fields
Not being able to reduce size to what we want
Accelerometer might not function well in low
temperatures
Anand
Component
Product
Quantity
Cost
Central Microcontroller
AVR ATTiny261
3
$7.50
Boot Microcontroller
MSP430 F2003
1
Donated
4
$132
1
$65
Mp3 player
1
$50
Push Button
1
$2
Printed Circuit Boards
Bluetooth Modem
BlueSMiRF Gold (WRL-00582)
Battery Lithium Ion
Polymer Lithium Ion 11.1V 2000mAh
1
$40
Housing Components and
Miscellaneous
Electric Field Sensor
Acrylic, Velcro, Polystyrene, Copper
wire,
MC33941
-
$150
2
Donated
1
$5
Pressure Sensor
Development Board for EFI
Sensor
KITMC33941EVM
1
$100
Accelerometer
ADXL335
1
$16
SRAM
KM68257CP-15
1
$8
GPS antenna
20 channel GS405
1
$90
ECG Parts
INA333, OPA2335, resistors, capacitors
$30
Total
$693.50
Anand
Kristen
Electro Field Imaging
Greg
X
Steven
Anand
John
L
Phone Interface
L
Boot Sensors
Power
X
L
Boot Microcontroller
GPS
X
L
Wireless
ECG
L
L
X
L
L
Chest
Microcontroller
L
Data Storage
L
Anand
John
CDR
Sensing component working
First Milestone
Full prototype
Second Milestone
Prototype reworked to within size constraints
Capstone
Completely working Project
John