the smart/safe car seat senior design ii final presentation

The Smart/Safe Car SeatSENIOR DESIGN II

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

Constraints Technical

Practical

Testing

Final Design

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

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: 43 [1]

1998 – Present: 605 [1]

Progress from Design I

Bluetooth Module Bluetooth Mate Silver

Rn-42 compatible with all PICs

Made by same company as PIC33

Overall Test Plan

Test PCB in lab Made sure all signals were correct compared to

bread board testing

Test PCB in Vehicle

Lab Testing

Test PCB with 12V buzzer and 12V source

Test Bluetooth connection through variety of conditions

Test LEDs in multiple outside lighting conditions How many LEDs and which

type works best?

Testing

Voltage divider going into Acc power supply:

Testing

Voltage divider going into lock motors:

Vehicle Testing

Test signals from vehicle

Test LED location (best visibility)

Pressure sensor placement

Heat test inside vehicle

Battery life

Test breaking point for the device

Full vehicle test

LED Alarm

10mm Ultra bright

5mm Red LED

5mm Green LED

5mm Wide-Angle Red LED

LED Voltage (V) Current (mA)

10 mm Ultra Bright 2.62 3.56

5mm Red 1.64 3.56

5mm Green 1.9 3.56

5mm Wide-Angle Red 1.66 3.56

Pressure Sensor

Tested different positions of pressure sensor in car seat with constant weigh of 5lbs Found most effective area

relevant to:

Voltage

Consistency

Re-tested with multiple pressure sensors and compared results

Bluetooth Testing Hallway Testing

Parking Lot Testing

15 meters walking distance before Power Alert

Clear communication at 20 meters with obstacles

Clear Communication at 40 meters without obstacles

PCB Schematic

BluetoothModule

TemperatureSensor

PIC33

VoltageRegulators

Heatsink

BJT

LAYOUT OF PCB

PressureSensor

Voltage Reg.& Heatsinks

Temp.Sensor

BluetoothModule

PIC33

MOSFET

BBJT

BOARD SIZE

• Dimensions of Board: 4.5”x 3.25”• Dimensions of Nokia Lumia 820: 4.8”x 2.80”

PACKAGING

Protective Casing

•Simcobox.com•Sparkfun.com•Radioshack.com

•Mouser.com – CU-3244-MB - $6.80

Final Product and Costs

dsPIC33EP $ 2.84

Bluetooth mate Silver $ 39.99

Temperature Sensor $ 0.35

Pressure Sensor $ 6.36

Ultra bright LED $ 1.20

12V Voltage Regulator $ 0.22

3.3V Voltage Regulator $ 0.69

MJE3055T $ 0.29

Box (packaging) $ 6.80 Misc. Passive Components $ 1.50

Total $60.24

The Smart/Safe Car SeatSENIOR DESIGN II

FINAL PRESENTATION