LightSaVers
Satya Bhan
Andrew Ausley
Michael Moseley
1
Modules
Project
Overview
Schematic
• ZigBee
Design
Decisions
&
Tradeoffs
Testing
&
Demo
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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
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Cypress
PSOC
Cypress
PSOC
Cypress
PSOC
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Shot range mesh network
Low power - 30mA/3µA
Data rates @ 250kbs
Standard
Bandwidth
Power
Consumption
Comparison
Wi-Fi
Up to 54 Mbps 400+mA/20mA
Overkill
Bluetooth
1Mbps
40mA/0.2mA
High power
X10
8bps
Negligible
Two slow
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Light sensor sampling directly via ZigBee
UART between microcontroller & ZigBee
Central controller makes decisions and sends
commands for light & blind modules
DAC
Digital outputs
Dimming Motor control
Cypress PSOC
TX
ZigBee
RX
ZigBee
ADC
Light
sensor
UART @ 19200 baud
6
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Unsuccessful at getting UART to work on PIC
Light dimming via current modulation
required a DAC not available on PIC
PIC replaced by more expensive cypress PSOC
Cypress PSOC provided an easy UART interface
along with DAC
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Transmitted sensor values using ZigBee
Implemented light dimming via DAC on PSOC
Controlled stepper motor using digital
outputs on PSOC
Transmitted and decoded commands from
the central controller
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Implement solution in Aware home and tweek
performance
Replace PSOC with cheaper compatible
microcontroller
Reduce design to minimum possible
microcontroller
Replace Maxstream XBee with cheaper ZigBee
modules
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Cover sensors and simulate the flowchart
System will not be run for a long period of
time due to robustness issues
Blinds may be operated manually pending
mechanical mounting of the stepper
The power savings will be tested by
measuring the current flowing to the light
fixture vs. that of an incandescent light bulb
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