The Smart/Safe Car SeatSENIOR DESIGN I

FINAL PRESENTATION

Andrew Evans (EE)Team Leader

Hardware/Coding for Microcontroller

Le’Quala Jackson (CPE)Bluetooth Module/Cell Phone Application/Website Design

Sam Stockstill (EE)Hardware/ Coding for

Microcontroller/ Bluetooth Module

Kyle Willis (EE)Hardware/ Coding for Microcontroller

Advisor:Dr. Raymond Winton

Our Team

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

Flow ChartPressure Sensor

Device Power On

Vehicle Off

LED Timer Starts

Timer StartsCar put in park

(locks unlocked)

Alarm Sounds

Timer Times Out

LED Flashes Alert Sent

to Phone

Dangerous Temperature

Detected

Car put in drive (locks

locked)

User locks car leaving

carTimer Times Out

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: Temperature Sensor

Detects temperatures within dangerous ranges.

Tied to Bluetooth module

Once temperature reaches danger zone, alert is sent to caregiver’s cell phone.

LM60 Temp. (F)Thermometer Temp.

(F)% Error

21.2 20.3 4.43%

32.3 32.8 -1.52%

40.1 40.6 -1.23%

50.7 51.4 -1.36%

61.4 60.9 0.82%

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%

Testing

Subsystem #3:Alarm 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 SeatSENIOR DESIGN I

MIDTERM PRESENTATION