Electrical candleECE 411 Practicum Project

Dung VoDuc Phan

Rami AlshafiTalal Alshammari

OutlineIntroduction

Needs

Motivation

Project objective

Alternatives

Requirements

Approach

DesignSchematic & layoutHardwareProgramming

Testing

Results

Lesson learned

Introduction

Tester, Editor EditorMechanical designer

ProgrammerLayout Designer

ProgrammerCircuit Designer

• Decision making• Design specification• Design modeling

• Test plan

ProblemThis is the term project for 411 class to

practice for capstone project (PCB layout, solder…)

Electrical candle

Motivation• To design a “toy”.• Team work.• Programming. • Fun to do

Objective• Skill practice (PCB layout, soldering…)• Apply knowledge• Complete the requirements.• The design of the electrical candle and it’s

prototype.

Alternatives Alternative features

Airflow sensor vs. acceleration sensor

Powering up the device (solar panels vs. batteries)

Color change dependence (music vs. remote control and acceleration )

Alternative productsA light that changes

colors continuously regardless of motion or any other inputs. Like the Halloween light toy candy.

Light changes due to sound or music

A light that changes with motion like the Play Station 3 wireless controller.

RequirementsFunctionality and performance: The final device should operate in normal

environment: ( 25 ° C dry room)Mode 1: Light colors and intensity is

depending on accelerationMode 2: light colors and intensity respond to

a remote controlPowering the toy: batteries and wall adaptor

ApproachR3T3SD: Research X 3, Think X 3, Specifications, Design

Fast is slowWorkload Building from

scratch vs. purchase

Design for extensibility (3 axis accelerometers vs. 2 axis)

Design for test (test points)

Design for environment (lead free)

Design

Schematic

Layout• Board dimension: 2.7 x 2.7 inch (7 x 7 cm)• Fit with the battery holder• Spare space on the board is filled with headers (Port B, C, D) with intention of later extensibility• Thru hold components

Layout - 3D view

Image created with Eagle 3D and POV-Ray

HardwareMicrocontroller: ATmega 328PAccelerometer: Fairchild MMA7260Q IR receiver: TSOP34338 – 38 KHz IR receiverRGB LEDs

ATmega328(Sparkfun)

Accelerometer breakout(Sparkfun)

IR receiver (Digikey)

RGB LED (Digikey)

ProgrammingAVR studio 4 is used for programming

Language:C

What need to be programmed?ADC for accelerometerDecode IR signalPWM for RGB LEDs

Source code and explanation are available on Wiki

http://ece411.wikispaces.com/Sourcecode

Test Strategy Unit tests

Microprocessor AccelerometerIR receiver and remote control

Functional test In Motion mode In Remote control mode

Power supply testOperation with batteriesOperation with wall adapter

Methodologies Start by testing beard board

Finish by testing PCB

•Unit tests•Functional tests•Power tests

•Functional tests•Power tests

Results LEDS color patterns control by:

Motion of the device Remote control

Power supply:Operate with 5V wall adapter supplyOperate with 3 AA battery packs

4 PCBs all works,We have 4 electrical

candles

Lesson LearnedMulti-cultural team workProject managementDocumentationsSkill: Eagle CAD, programming, soldering…

What need to improve:Effective meetingTime management

What would we do differently? Design more fancy housingUse surface mount devices Extend functionalities, e.g. sync LEDs color with music

Referenceshttp://ece411.wikispaces.comhttp://web.cecs.pdx.edu/~faustm/ece411/

Q & A

Thank you for attention!