Download Type Name Description

The
Smart/Safe
Car Seat
SENIOR DESIGN I
FINAL PRESENTATION
Our Team
Le’Quala Jackson (CPE)
Bluetooth Module/Cell Phone
Application/Website Design
Andrew Evans (EE)
Team Leader
Hardware/Coding for
Microcontroller
Advisor:
Dr. Raymond Winton
Sam Stockstill (EE)
Hardware/ Coding for
Microcontroller/ Bluetooth Module
Kyle Willis (EE)
Hardware/ Coding
for Microcontroller
Outline

Problem

Solution

Flow Chart

Constraints

Technical

Practical

Prototype Design

Testing

Questions
Problem

Extreme temperatures are reached in minutes
inside vehicles when turned off

Caregivers getting out of daily routine and/or in
an extreme hurry

The available electronic technology is not being
utilized
Solution

Device works without the caregiver having to do
anything out of the ordinary

Multiple sensors and Bluetooth module

Multiple catch safes in case one system fails or
goes unnoticed during use
Pressure
Sensor
Flow Chart
Device
Power On
Car put in drive
(locks locked)
Vehicle Off
LED Timer
Starts
Timer
Times Out
LED
Flashes
Dangerous
Temperature
Detected
Timer Starts
Timer
Times Out
Alert Sent
to Phone
Car put in park
(locks unlocked)
User locks car
leaving car
Alarm
Sounds
Technical Constraints
Name
Description
Temperature
Device must be able to detect temperatures
between 0oF and 120oF.
Pressure Sensor
Device must be able to detect a weight of at
least 5lbs. [2]
LED and Alarm
Device’s LED and alarm alerts must be
distinguishable from other alerts.
Battery
Device will be powered by vehicle’s battery.
Communication
Compatibility
Device must be compatible with Android OS.
The device must also be able to connect to the
caregiver’s cell phone through Bluetooth.
Practical Constraints
Type
Name
Description
Sustainability
Durability
The device must be able to withstand motion
and vibration of the vehicle, coming in
contact with moisture, and a vast range of
temperatures.
Health and Safety
Safety
This design aims to prevent deaths by helping
reduce the problem of caregivers forgetting
their children in vehicles unattended.
Sustainability
The device must be able to work under many types
of conditions:

Moisture

Vibrations and movement from vehicle

Extreme temperatures
Health and Safety
Documented cases of children dying of heatstroke in
United States directly related to being left in vehicles:

2013: 42 [1]

1998 – Present: 604 [1]
Prototype Design
•
Our design consists of:


Hardware

Pressure Sensor (Force Sensitive Resistor)

Temperature Sensor (LM60CIZ – Ambient Temperature
Sensor)

Bluetooth Module (HC-05)

Voltage Divider/Voltage Regulator

dsPIC33EP128GP

Power (Car Battery)

Horn/Lock Mode
Software

Cell Phone Application
Testing on Breadboard
Testing
 Subsystem

#1:
Pressure Sensor

Weights placed
on Sensor up to
20 lbs.

Voltage
Readings taken

Voltage Reading
notifies that a
weight is present
and Car Seat
Turns On
Testing
 Subsystem

#2:
LM60 Temp. (F)
Thermometer Temp. (F)
% Error
21.2
20.3
4.43%
Detects temperatures within
dangerous ranges.
32.3
32.8
-1.52%
40.1
40.6
-1.23%

Tied to Bluetooth module
50.7
51.4
-1.36%
60.9
0.82%

Once temperature reaches
danger zone, alert is sent to
caregiver’s cell phone.
61.4
70.8
70.3
0.71%
81.1
80.8
0.37%
92.1
92.4
-0.32%
100.8
101.2
-0.40%
111.3
111.9
-0.54%
120.6
121.2
-0.50%
Temperature Sensor

Testing
 Subsystem
 Alarm
#3:
and LED
 Alarm
consists of the car horn blowing
when pressure sensor is on and locks
are pressed after driver has parked.
 LED
flashes 5 seconds after accessory
power has turned off.
 Accessory
power turns off after 20
seconds of car being turned off.
Testing
 Subsystem

#4:
Communication Compatibility

Cell phone application

Bluetooth waits on accessory
timer to expire to send alert to
caregiver’s phone.

When temperature has
reached dangerous
temperature alert is sent to
caregiver’s phone.
Testing
 Subsystem

#5:
Battery Life

Tied to battery of car

Life expectancy
overall is based on the
car battery
Full System Test

Mass placed in car seat,
Pressure Sensor detects
weight and device comes
out of sleep mode

Car is turned off and timer
starts for Alarm LED

Lock check

Temperature Sensor
constantly detects
temperature. Alert sent to
phone when reached
dangerous temperatures.

Bluetooth connection
checked. Alert sent to phone
when accessory timer
reaches 25 seconds

Pressure Sensor no longer
detects mass - System turns
off
References
[1] J. Null. (10 July 2013). Heatstroke Deaths of Children in Vehicles [Online]. 1 October 2013.
Ggweather.com. Available: http://www.ggweather.com/heat/
[2] (17 September 2013). Low Birthweight [Online]. www.lpch.org. Available:
http://www.lpch.org/DiseaseHealthInfo/HealthLibrary/hrnewborn/lbw.html
The
Smart/Safe
Car Seat
SENIOR DESIGN I
MIDTERM PRESENTATION