Senior Project -Computer Engineering- 2005

Hyperthermia Alarm For Automobiles

Brian Gaugler and Betsy McPhailAdvisor: Professor Traver

What is Hyperthermia?

General name given to a variety of heat-related illnesses

Exhaustion and heat stroke are most common

Can cause severe illness and even death

Children or pets left in an automobile can suffer from hyperthermia

Background

0

5

10

15

20

25

30

35

40

45

1999 2000 2001 2002 2003 2004

U.S. Hyperthermia Fatalities 2000 - Sept 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

Design system to monitor conditions inside vehicle

System will alert driver and others of dangerous situations

Solution

Behavior

Start car

alarm

Start Timer

Send signalto handheld

alarm

Motion inside of car?

Temperature too hot?

Roll down

windows

Yes

Yes

No

Timeleft?

No

Yes

Driver response? Yes

No

No

Components

Motion Sensors

Microcontroller

Car Battery

Window Switch

Car Alarm

Transmitter

Receiver

Battery

AlarmTemperature Sensor

Constraints

Power Handheld Alarm Battery Car Battery

Size Handheld Alarm Car Component

Consumer Cost

Performance Criteria

Motion Sensing Sensitivity Range

Temperature Sensing Reliability

Transmitting/Receiving Signals 1000 meters minimum No line of sight

Battery Life

No False

Alarms!!!

No

Hyperthermia

Accidents!!!

Functional Block Diagram

Motion Sensors

MicroprocessorTemperature

Sensor

TransmitterCircuit

RelayCircuit

PowerWindows

ReceiverCircuit

Buzzer

RelayCircuit

CarAlarm

Power Block Diagram: Car Component

Battery 12V

Voltage Regulator

5V

VoltageRegulator

3.3V

Temperature Sensor

Motion Sensors

Transmitter Microcontroller

MOSFET

MOSFETRelays

Car HornWindowMotor

Power Block Diagram: Handheld Receiver

Battery 9V

Voltage Regulator

5VReceiver

Buzzer

VoltageDivider1.15V

VoltageComparator

Motion Sensors

Passive InfraRed (PIR) Motion Detector 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

LM34DX Precision integrated-circuit temperature sensor

Output voltage linearly proportional to ambient temperature (~10mV/1oF)

Output to ADC of microcontroller

Transmitter/Receiver

T7/R7 FM narrow band radio modules Operating Frequency:

433MHz Transmitter:

When supplied with power, continually transmits a signal

Receiver: Carrier Detect pin

voltage proportional to input signal

1.15V

Carrier Detect

Time

{{

Signal

Noise

Car Horn and Windows

Controlled by microcontroller

Relay circuit needed to supply necessary current

Power

Car Battery Rechargeable Voltage Regulators

9 Volt Battery

Software: AlgorithmMonitor Motion

Motion?

no

Set Timer for 5 mins

Time left?

Monitor Temperature

yes

no

T > 90oF?

yes

yesno PowerTransmitter

Set Timer for 5 mins

Time left?

no

yes

Reset?yes

Roll Down Windows

Sound Alarm

no

Results: Goals Accomplished

Motion Sensor

MicroprocessorTemperature

Sensor

Transmitter

Relay

WindowMotor

Relay

CarHorn

Analog

0.1V/oF

Motion SensorDigital

0V/5V

Digital

0V/5V

MOSFET

Relay

MOSFET

MOSFET Relay

P3.1 P3.3

AIN0 P3.6

P3.5

P3.4

Digital

0V/3.3V

Digital 0V/3.3V

Digital 0V/3.3V

Digital 0V/3.3V

0V/3.3V

0V/3.3V

Results: Goals Accomplished

Voltage Regulator Receiver

BuzzerVoltageDivider

VoltageComparator

Antenna

Carrier Detect Pin ~1.09V – 2.58V5V

1.15V 0V/5V

5V

Results: Software

C

Interrupts Timer 2 4 interrupts/second

Analog to Digital Converter

Results: Prototype vs. Production Model Microcontroller

Power Source

Transmitter/Receiver Range Encoder/Decoder

Motion Sensor Sensitivity

Demonstration

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…

Special Thanks to…. Prof Traver Prof Spinelli Prof Rudko Prof Hedrick Gene Davis Dan and Mike