ECE 4884: Senior Design Project

1

2

Automated light balancing via remote blinds and dimmers

Centralized, low-power wireless network Low bandwidth information feed via

remote sensor network LED-based light fixture

3

4

5

6

ZigBee network model

Standard Bandwidth Power Consumption

Wi-Fi Up to 54 Mbps 400+mA/20mA

Bluetooth 1Mbps 40mA/0.2mA

ZigBee 250 kbps 30mA/3µA

7

8

9

Use low-cost, accurate LX1972 ambient light detector

Produces output current vs. measured light

Modulated via a stepper motor interfaced with the tilt mechanism

Current, minimum, and maximum tilt positions will be recorded

48 steps/rev. @ 5VDC

10

Low-power, LED based lighting Automated dimming using a microcontroller Transformer-less power supply AC pulse width modulation

11

Triac signal and dimming – figure shows 52% dimming

12

Type Prototype 1unit @ 10,000 Units

Components $146 <$73

Labor $16,000 $10Departments Avg.

Cost/Year

Assembly $100,000

Random Testing $10,000

1unit @ 10,000 Units

Overall Cost $211

Retail $250

Profit Margin

15.6%

Money Back in 5 years!!Money Back in 5 years!!

13

*all calculations provided by the given spreadsheet

ZigBee◦ Central designs vs. distributed system◦ ADC packet decoding

Stepper motor◦ Blind initialization◦ Installation

Lighting◦ AC vs. DC package ◦ Commercial cost effective LEDs

14

15

Cover sensors Simulate flowchart Allow the system to run for an extended

period of time > 1 day Tested by measuring the current flowing to

the light fixture vs. that of an incandescent light bulb

16

The system will be implemented in the Aware Home on 10th St.

The flowchart simulation will be demonstrated as well as the measurement techniques for measuring the current

“I recognize the right and duty of this generation to develop and use our natural resources, but I do not recognize the right to waste them, or to rob by wasteful use, the generations that come after us.”

- Theodore Roosevelt, speech,  Washington, D.C., 1900

17