Department of Electrical and Computer Engineering

Lighting Tool Box

Winter 2004ECE 498

Team Members:Nick Sitarski

Blaine ThompsonBrandon HarrisDave Chronicle

Vladi Gergov

Advisor: Professor John W. Miller

Department of Electrical and Computer Engineering

Project Summary

• The Lighting Tool Box is a collection of common machine vision lighting systems controlled locally or via the Internet

• The goal of this project is to design and implement three lighting controllers which interface with a Linux based embedded controller

• The embedded controller supports the Web Cam and Internet interface as well as PWM signal syntheses

• The Incandescent System can provide the 360 degree lighting for requirements such as structured lighting

• A fluorescent Lighting system was developed for applications that require a large aspect ratio

• An LED ring light was developed for applications requiring close proximity inspections

• Each lighting subsystem can be operated in a stand alone configuration

• All major functions of the three lighting systems were designed and implemented with the exception of the following features

– No lamp voltage regulation on incandescent system

– No computer controlled strobe only through local hardware

– No remote health status detection

Department of Electrical and Computer Engineering

Design Requirements• The system was designed to be operated in a factory

environment, thus size, ease of remote use, and construction was considered during design stages

• The whole system can be run via the internet/network or through local operation

• Equipment should be portable, easy to connect / disconnect • All systems are powered from 120 VAC• Embedded microcontroller used for remote operation• Lighting parameters must be maintained at constant value

once set• Construction of equipment must comply with electrical safety

codes to minimize hazards to user and risk of fire

Department of Electrical and Computer Engineering

Technical Specifications• Embedded Controller

Enclosure Dimensions: 6.5”x4.5”x3.5”Processor Speed: 300 MHzOperating System: GNU/LinuxWeight: 2 lbs.Power requirements 120 VAC @50 watts

• Incandescent SystemEnclosure Dimensions: 11”x17”x9.5”Lamp Enclosures: 4”x4”x8”Weight: 30 lbs. Power requirements 120 VAC @250 watts

• LED SystemEnclosure Dimensions: 11”x15”x9.5”Ring Light: 4”x4”x2”Weight: 10 lbs.Power requirements 120 VAC @50 watts

• Fluorescent SystemEnclosure Dimensions: 8”x10”x2.5”Tubular Light Enclosure: 48”x4”x4”Shadow Box Enclosure: 12”x12”x5”Weight: 5 lbs. Power requirements 120 VAC @50 watts

Department of Electrical and Computer Engineering

Subsystems• LED Lighting System (Blaine Thompson) - The LED subsystem is a

single channel system that controls a LED ring light. The intensity is controlled via a 40KHz PWM signal. This subsystem also contains a strobe feature that modulates the LED ring light output. This is ideally suited for close proximity viewing.

• Fluorescent Lighting System (Brandon Harris) – The fluorescent lighting system uses an electronic ballast to power and precisely control the intensity of a 32 W fluorescent bulb. This is used for large aspect-ratio viewing.

• Incandescent Lighting System (Nick Sitarski) – The Incandescent subsystem is a 4 channel system that powers and precisely controls the intensity of the 4 halogen lamps. This is typically used for 360° illumination applications.

• Microcontroller (Vladi Gergov, David Chronicle) - The embedded microcontroller uses a combination of microprocessors, I/O, and networking to control the lighting systems remotely via the internet or network.

Department of Electrical and Computer Engineering

Design Constraints

• Maximum power output is limited to 32 Watts for fluorescent subsystem controller. Major circuit redesign is required to exceed this power restriction.

• The Incandescent subsystem controller is not regulated for remote operation due to time and economic constraints. A high performance A/D IO card is required as well as extensive programming.

• Had to construct LED ring light due to cost constraints.• Economic constraints limited transformer size for Incandescent

subsystem allowing a maximum lamp size of 35 W.• Strobing features could not be implemented in software due to

time constraints.

Department of Electrical and Computer Engineering

Design Options

• PWM Signal synthesis is generated via an embedded controller as opposed to local hardware to reduce complexity of hardware design.

• Modular design of system components and website for easier maintenance and prototyping

• Build custom hardware for lighting subsystems as opposed to commercially available product to reduce cost

• Operating system (open source, commercial, or custom)– Linux was chosen due to its lack of licensing fees, open

source, stability, and less resources required– PC/104 technology for compact, low power requirements

Less heat dissipation and greater heat tolerance.

Department of Electrical and Computer Engineering

Logical Schematics

Light 2 Out

Light 3 Out

Light 4 Out

Light 1 Out

PowerSupply

LPFs

SignalConditioners

Local/RemoteSwitch

Local PWMGenerator

MOSFETSRemote PWM 1

Remote PWM 2

Remote PWM 3

Remote PWM 4

Lamp 1 VoltageLamp 2 VoltageLamp 3 VoltageLamp 4 Voltage

Common toMicrocontroller

AC In

Incandescent LightingSystem

Strobe In

Ring LightOut

PowerSupply

TriggerCircuit

HealthStatus

Local/RemoteSwitch

Local PWMGenerator

MOSFETSRemote PWM

Common toMicrocontroller

AC In

LED Lighting System

Health Signals toMicro Controller

Light Out

PowerSupply

LPFs

ElectronicBallast

Local/RemoteSwitch

Variable DCVoltage Source

Remote PWM

Common toMicrocontroller

AC In

Fluorescent LightingSystem

Department of Electrical and Computer Engineering

Test Results

• Integrated system test was performed satisfactorily with minor exceptions

• Exceptions include– Limited range of control for incandescent lamp output due

to biasing method for MOSFET’s, in the future a scaling amplifier will be added to condition the PWM signal

– Embedded controller safety ground must be disconnected when operating Fluorescent controller

– Strobing test were not performed, software integration was not complete

– Lamp voltage regulation test showed that the microcontroller’s A/D board was not fast enough to regulate the lamp voltage

Department of Electrical and Computer Engineering

Conclusions and Future Work

• Project scope was large• Four systems total• Both CE/EE skills required • Main functions were implemented successfully• Project cost were higher than expected • Improvements/optimizations can be made• Advisor has expressed interest in continuing project

in future semester• Advisor has expressed an interest in co-authoring a

paper based on the Lighting Tool Box

Department of Electrical and Computer Engineering

Acknowledgements

Individuals• Professor Miller –

– Support with electronic design– Donation of material– Providing us with a lab

• Professor Shridhar – – Allowing a project this large with 5 members

• Companies • Stancor – Donation of $150.00 in power supply transformers• Bud Industries – Donation of electronic enclosure for LED light

controller• GNU – For open source software• Linux – For open source Kernal

Department of Electrical and Computer Engineering

Data Flow Graphic

Hardware

Software

Web Service

lightingtoolbox.com

Console void main()

{Cout<<“Hello World”;Cout<<endl;Cout<<“Linux is good”;}

Department of Electrical and Computer Engineering

Pictures