Transcript Final Draft - Senior Design

Senior Design I
Mid Semester Presentation
October 9, 2014
Team
John Corn
Alex Gibson
Jordan Klein
Shane Reeves
Dr. Koshka
EE
EE
CPE
EE – Team Leader
Team Advisor
Outline
• Problem/Market
• System Overview
• Review of Subsystems
• Progress
• Timeline
Market
• Guitar interfaced synthesizers are virtually nonexistent
• No guitars with lasers on the market
• Market towards all musicians
Economic Practical Constraint:
The Guitar must not cost more than $500.
Systems
•
•
•
•
•
Microcontroller
Lasers
Power Supply
Fretboard Finger Positioning
Synthesizer
Microcontroller
Audio Latency Technical Constraint:
The processor must detect a broken beam and output sound within 50ms.
Device
Pros
Cons
Arduino Due
-84MHz CPU speed
-2 DAC I/O pins
-12 Analog I/O pins
Arduino Mega2560
-Currently owned
-16 Analog I/O pins
- 16MHz CPU speed
Photodiodes
Light Detection Technical Constraint:
Photodiodes must detect light wavelengths
between 500nm and 600nm.
[2]
[2]
Lasers
30mW Green Laser Module
Wavelength: 532nm
Operating Voltage: 3V
Operating Current: 360mA
Health and Safety Practical Constraint:
The laser beams must be safe to the touch under normal operational conditions.
[3]
Power Supply
Device
Quantity
Voltage
Current
Total Current ( Three Hours )
Laser
12
3V
360 mA
12960 mA
Microcontroller
1
7 - 12 V
50 mA
150 mA
Synthesizer
1
3.3 V
18 mA
54 mA
Battery
2
7.4 V
6600 mAh
13200 mAh
[4]
Fretboard Finger Positioning
Technology
Pros
Cons
Membrane
Potentiometers
- Easy to implement
- Stable operation
- Expensive ($25 x 6)
- Not visually appealing
Capacitive Sensing
- Visually appealing
- Inexpensive
- Difficult to implement
- Requires significant calibration
Laser Time-of-Flight
- Visually appealing
- Precise measurements
- Extremely Difficult to implement
Capacitive Sensing
• A simple RC circuit is used
• One plate of the capacitor is formed by a metal contact on the guitar and the other plate
is formed by the finger of the player
• The time it takes for the Receive pin to read HIGH after
the Send pin has been set HIGH will vary based on changing capacitance
Metal
Contact
~
Player’s
Finger
Capacitive Sensing
• A simple RC circuit is used
• One plate of the capacitor is formed by a metal contact on the guitar and the other plate
is formed by the finger of the player
• The time it takes for the Receive pin to read HIGH after
the Send pin has been set HIGH will vary based on changing capacitance
Capacitive Sensing
• The 22 frets on the guitar will be used as the metal contacts
• Capacitive sensing begins when a laser beam on the neck of the guitar is broken
Synthesizer
How Does a Synthesizer work?
By combining multiple sine waves and adjusting amplitude, a
synthesizer can create a new waveform.
Synthesizer
Technology
Pros
Cons
Arduino Synth Library
-Easy to implement
-Open source
-Limited Functionality
SAM2695 Synthesizer
-Extensive sound library
-Onboard effects
-Difficult to implement
Synthesizer – SAM2695
The SAM2695 has functions for 128 instruments that support over 100 notes.
This will function like a keyboard that has multiple instrumental settings.
Synthesizer – SAM2695
Capabilities:
• 64-voice polyphony (without effects)
• 38-voice polyphony + effects
• On-chip CleanWave™ wavetable data,
firmware, RAM delay lines
Synthesizer – SAM2695
48 pin package
[6]
SAM2695 -Low power single chip synthesizer with effects
and built-in codec
Synthesizer – SAM2695
What is a codec?
Data
Codec
Data
A codec takes data and compresses/decompresses it so it can be
transferred/received faster.
Progress
• Formulated overall approach
• Lasers and photodiodes ordered and received
• Capacitive sensing tested
• Laser detection via photodiodes tested
• SAM2695 synthesizer chip ordered
• Issue with laser overheating resolved
Progress – Overheating Lasers
Progress – Pulsing Lasers
Timeline
References
[1] Available:
http://arduino.cc/en/Products.Compare
[2] Available:
http://advancedphotonix.com/wp-content/uploads/PDB-C142.pdf
[3] Available:
https://www.dx.com/p/30mw-532nm-green-laser-module-3v-11-9mm-26888
[4] Available:
http://www.all-battery.com/li-ion1865074v6600mahrechargeablebatterymodulewithpcb.aspx
[5] Available:
http://makezine.com/projects/make-35/advanced-arduino-sound-synthesis/
[6] Available:
http://www.dream.fr/pdf/Serie2000/SAM_Datasheets/SAM2695.pdf
Senior Design I
Mid Semester Presentation
October 9, 2014