1. Atreyee Roy, Siddharth Sharma
ECE 445 Spring 2017
Group 57
Water Aliasing
Atreyee Roy, Siddharth Sharma

2. Compare frequencies of water and light
Introduction
Perform levitation, up, and down motion of water as an optical illusion
Compare frequencies of water and light
Control water movement with app
Cheaper than similar market products
Sid

3. Gravity Defying Products cost ~ $500-$600 Make it cheaper
Primary Objectives
Gravity Defying Products cost ~ $500-$600 Make it cheaper
Provide feeling of “waterbending”
Controlled by the user easily
See distinct, well shaped droplets
Sid

4. Functional Block Diagrams
Atreyee

5. System Overview Hardware 555 chip Transistor LEDs Android device
Bluetooth Module HC-05
Elegoo Mega2560
SN76489AN Sound Generator IC
Amplification circuit (using LM1875)
6 ohm 20 W speakers
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6. Android App (built using Android Studio, Java) Arduino IDE
System Overview
Software
Android App (built using Android Studio, Java)
Arduino IDE
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7. Physical Design
Atreyee

8. Light Strobe
Atreyee

9. 555 Circuit Requirements Frequency: 100 Hz Duty Cycle: 10%
LED branch currents < 20 mA
Design
Potentiometers (100K) for tunability
Diodes in 555 circuit
150 ohm limiting resistors
Atreyee

10. Total Power Dissipated in Circuit :
R2 = 9*R1
f = 1.44/ C*(R1 + 2R2)
Total Power Dissipated in Circuit :
1559 mW
D = R1/ (R1 + R2)
Atreyee

11. User Interface
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12. Android App
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13. HC-05 Bluetooth Module HC05 Pin -> Elegoo Board Pin
RXD -> TXD (1) TXD -> RXD (0) GND -> GND (GND) VCC -> 3.3V (3.3V)
Range: 10 metres/30ft
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14. Water Module
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15. F = N/(32*n) Sound Generator SN76489AN Input clock at 500 kHz
Frequency set by bytes received by Elegoo via bluetooth from mobile app:
F = N/(32*n)
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16. Amplifier
LM1875 Chip
Provides 25 W of power
Atreyee

17. Speakers Requirements Output Range: 90 - 110 Hz
Filter out large, unwanted frequencies
Speaker can vibrate pipes
Design
Sound Generator output to amp input
Amp output to Speaker input
Operational frequencies of Hz
Rated at 20 W, 6 ohms
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18. Conclusion Evaluation Met requirements Could show end results
Arduino and Bluetooth experience
App Development
Future work
Fix amplifier circuit
Choose better pipes
Scale up to see multiple streams
Introduce a more engaging user experience
Conclusion
Atreyee

19. Acknowledgements
We would like to thank the following people:
Scott Mcdonald and Skee Aldrich
Skot Wiedmann
Casey Smith
Professor Michael Oelze
TAs Luke Wendt, Jackson Lenz, and Vignesh Sridhar