ECEN 4610 Capstone University of Colorado Boulder, CO January 29, 2009 School of Rock PDR Cheyenne Aberle Drew Veldhuizen Swain Brooks Dan Reed

ECEN 4610 Capstone Now Presenting… 2 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen Drew Veldhuizen

ECEN 4610 Capstone Project Overview 3 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Design  PCB mounted in body of guitar.  Motors mounted to the back side of the head of the guitar.  Using DSP, A/D converters, and microcontroller, analyze signal and control motor movement to achieve desired pitch.  User Interface via LCD touch screen.  Multi-colored LED’s next to each string to indicate in tune or out of tune. 4 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Block Diagram 5 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Guitar  Electric guitar  Audio output jack on guitar outputs signal for analysis  Signal output via magnetic “pick-ups” already built into the guitar  Looking for guitar at local shops and online  Based on measurements, torque on tuning knobs requires 12 to 16 oz-in 6 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone PCB Design  MSP430 Microcontroller  Motor Drives  Six drives will be built and used to control six stepper tuning motors, one for each tuning knob.  DSP Processing Chip  Using Fourier Transforms, will process frequency of each string and determine how far off it is from the correct pitch.  Accelerometer  Used for effects similar to star power in Guitar Hero.  LCD/Touch Screen  GUI for tuning presets, effects, and feedback to user 7 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Now Presenting… 8 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen Cheyenne Aberle

ECEN 4610 Capstone Microcontroller  TI MSP bit microcontroller  32 kHz, 1.8V to 3.6V, ultra-low-power  Interface to DSP chip through I 2 C communication 9 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone DSP Chip  Freescale Semiconductor DSPB56371  24-bit Audio Digital Signal Processor  Utilizes I 2 C communication with microprocessor  180MHz core, 3.3V 10 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Filtering  Filtering performed in the microcontroller  Ideally, strum all strings at once and circuit filters signals, outputs information to each motor controller for optimized tuning  The guitar might need to be strummed 3 to 4 times to provide adequate data for the tuning circuit 11 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Motor Design  Stepper Motors similar to the Sure Step 83oz-in motor will be used to turn the tuning knobs on the guitar head.  Motors will be mounted on the head with wires run through the neck of the guitar to the microcontroller. 12 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Power  AC to DC Power Converter  Plugs into 120VAC 60Hz outlet.  Used to recharge the battery  Also good application for use at a performance  Ensures guitar always has enough power for tuning during a show  Rechargeable Lithium-Ion battery  Able to supply enough power to tune the guitar a few times before recharging is necessary. 13 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Now Presenting… 14 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen Dan Reed

ECEN 4610 Capstone User Interface  LCD Touch Screen  Creates a graphical user interface  Allows user to select different tuning schemes  Drop D, double drop D, standard, etc  User can also customize tuning scheme  Most logical would be a lay-over resistive touch screen for an LCD display  LED’s  Next to each string below the bridge.  Indicates in or out of tune for each string based on the color (eg. Green for in tune, red for out of tune) 15 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Effects  Adding effects to the guitar can up-scope this project if needed  Distortion, Wah Wah, Reverb, etc…  The XYZ accelerometer will determine which effect is enabled based on the direction the guitar moves.  Can increase (1) the ease of turning on effects and (2) the excitement of performances. 16 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Implementation  PCB will be set into the body of the guitar.  Motors will be attached to the head of the guitar.  The LCD touch screen can be mounted in the front or back of the guitar body, whichever is more convenient to the user.  The rechargeable battery will be mounted in the backside of the guitar body with an input jack for the AC to DC power converter. 17 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Schedule 18 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Division of Labor  Drew Veldhuizen  Motor Control  PCB Design  Dan Reed  PCB Design  Software 19 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen  Cheyenne Aberle  DSP  Mechanical / Control  Swain Brooks  DSP  Software  Group  Technical and User Manual

ECEN 4610 Capstone Now Presenting… 20 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen Swain Brooks

ECEN 4610 Capstone Budget 21 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen Item#Cost Per ItemTotal Notes Guitar1100 Guitar Strings5630 Stepper Motors Motor Drivers PCB140 Microcontroller DSP Chip Development Board100Borrowed from Capstone Misc (cables, connectors, shipping, etc)1150 Accelerometer135 Touch Screen1100 LCD Screen1100 A/D Converter18.91 D/A Converter144 Battery32575 Battery Charger125 Flash Memory110 LEDs Total939.54

ECEN 4610 Capstone Extra Features  Accelerometer  USB output used for recording  Visualizer on LCD screen and/or LEDs 22 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Risks  Not everything will fit inside the guitar  Create external enclosure to house electronics  Motors might end up being too large to fit on the head of the guitar  Separate free standing enclosure for motors  Touch Screen does not work  Use LCD and push buttons  Not enough time for effects  Not essential for project 23 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Fall Back Plan  LCD user interface with corresponding buttons.  Set tuning schemes, not customizable.  No effects, accelerometer used to activate the tuning program.  No battery, just use power cable. 24 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen

ECEN 4610 Capstone Questions Any Questions? 25 Capstone PDR ECEN 4610 Dan Reed Cheyenne Aberle Swain Brooks Drew Veldhuizen