Transcript Hyperthermia Alarm For Automobiles

Senior Project -Computer Engineering- 2005
Hyperthermia Alarm For Automobiles
Brian Gaugler and Betsy McPhail
Advisor: Professor Traver
What is Hyperthermia?

General name given to a variety of heat-related
illnesses
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Exhaustion and heat stroke are most common
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Can cause severe illness and even death
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Children or pets left in an automobile can suffer
from hyperthermia
Background
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U.S. Hyperthermia Fatalities
2000 - Sept 2004
45
40
35
30
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25
20
15
10
5
0
1999
2000
2001
2002
2003
2004
Hyperthermia causes
over 30% of parked
vehicle related deaths
yearly
From 1998 to July 31,
2004 there have been at
least 214 deaths
attributed to
hyperthermia
Project Goals
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Design system to monitor conditions inside vehicle
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System will alert driver and others of dangerous
situations
Solution
Behavior
No
Motion
inside
of car?
Send signal
to handheld
alarm
Yes
Temperature
too hot?
No
No
Driver
response?
Yes
Start
Timer
Time
left?
Yes
Start
car
alarm
No
Roll
down
windows
Yes
Components
Car
Alarm
Motion Sensors
Window Switch
Microcontroller
Battery
Transmitter
Car
Battery
Temperature
Sensor
Receiver
Alarm
Constraints
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Power
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Size
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Handheld Alarm Battery
Car Battery
Handheld Alarm
Car Component
Consumer Cost
Performance Criteria
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Motion Sensing
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Temperature Sensing
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Reliability
Transmitting/Receiving Signals
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Sensitivity
Range
1000 meters minimum
No line of sight
Battery Life
Functional Block Diagram
Transmitter
Circuit
Motion Sensors
Temperature
Sensor
Receiver
Circuit
Microprocessor
Buzzer
Relay
Circuit
Power
Windows
Relay
Circuit
Car
Alarm
Power Block Diagram: Car Component
Temperature
Sensor
Voltage
Regulator
5V
Relays
Window
Motor
Battery
12V
Car Horn
Motion
Sensors
MOSFET
Voltage
Regulator
3.3V
Microcontroller
MOSFET
Transmitter
Power Block Diagram: Handheld Receiver
Battery
9V
Voltage
Regulator
5V
Receiver
Voltage
Comparator
Voltage
Divider
1.15V
Buzzer
Motion Sensors
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Passive InfraRed (PIR) Motion
Detector
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Will not detect motion through
windows
Will not detect changes in
temperature or light
Positioned over seats
High/Low output to port of
microcontroller
Temperature Sensor
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LM34DX Precision
integrated-circuit
temperature sensor
Output voltage linearly
proportional to ambient
temperature (~10mV/1oF)
Output to ADC of
microcontroller
Transmitter/Receiver
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T7/R7 FM narrow band
radio modules
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Transmitter:
When supplied with power,
continually transmits a signal
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Carrier Detect pin voltage
proportional to input signal
Carrier
Detect
1.15V
Noise
{
Receiver:
Signal
{

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Operating Frequency:
433MHz
Time
Car Horn and Windows
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Controlled by
microcontroller
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Relay circuit needed to
supply necessary current
Power
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Car Battery
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Rechargeable
Voltage Regulators
9 Volt Battery
Software: Algorithm
Monitor
Motion
no
Motion?
yes
Set Timer
for 5 mins
Roll Down
Windows
no
yes
Time left?
Time left?
no
Sound
Alarm
yes
Monitor
Temperature
no
T>
90oF?
Set Timer
for 5 mins
yes
Power
Transmitter
no
yes
Reset?
Results: Goals Accomplished
Digital
Motion Sensor
0V/3.3V
0V/5V
Relay
Digital
Motion Sensor
Digital
0V/3.3V
0V/5V
P3.1 P3.3
P3.5
MOSFET
Window
Motor
Relay
Microprocessor
Temperature
Sensor
Analog
0.1V/oF
AIN0
MOSFET
P3.6
P3.4
Digital
0V/3.3V
Digital
0V/3.3V
Digital
MOSFET
0V/3.3V
Transmitter
Relay
Relay
0V/3.3V
Car
Horn
Results: Goals Accomplished
Antenna
Voltage
Regulator
5V
Carrier Detect Pin
~1.09V – 2.58V
5V
Voltage
Divider
Receiver
1.15V
Voltage
Comparator
0V/5V
Buzzer
Results: Software
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C
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Interrupts
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Timer 2
4 interrupts/second
Analog to Digital Converter
Results: Prototype vs. Production Model
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Microcontroller
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Transmitter/Receiver
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Power Source
Range
Encoder/Decoder
Motion Sensor Sensitivity
Demonstration
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Simulation of system
2 motion sensors and a temperature sensor
Hand-held buzzer will sound if “sun” and motion
Car horn will sound and window motor will run if
system not reset within 1 minute
Thank You…
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Special Thanks to….
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Prof Traver
Prof Spinelli
Prof Rudko
Prof Hedrick
Gene Davis
Dan and Mike