Jordan Wagner Justin Spencer Mark Sears John Jachna

ECE 477 Design Review Team 20 Fall 2012

Jordan Wagner

Justin Spencer

Mark Sears

John Jachna

Project overview Project-specific success criteria Block diagram Component selection rationale Packaging design Schematic and theory of operation PCB layout Software design/development status Project completion timeline Questions / discussion

Outline

Our team is implementing a smartphone controlled marble

maze. Players guide a marble through a maze by controlling

the degree of tilt of the playing surface via a wireless link to a

smartphone. The accelerometers in the smartphone capture

the players' input and relay it to the game controller. The

game controller then adjusts the tilt of the playing surface via

stepper motors on each axis.

Project Overview

1. An ability to manipulate the playing surface via stepper motors.

2. An ability to control the playing surface with accelerometers in an iPhone and resistive joysticks.

3. An ability to detect the player's failure or success using IR gates.

4. An ability to display game statistics & configuration information on an LCD and play game related tones on a speaker.

5. An ability to store separate, specific game data on the board and on the iPhone.

Project-Specific Success Criteria

Block Diagram

PIC18F67J94• Fast clock speed, up to 64 MHz

• Many serial communications options – 4 USART and 3 SPI/I2C channels

• Large flash memory – 128KB

• Copious amounts of analog and PWM channels, as well as plenty of GPIO pins – 64 pin package

Microcontroller Choice

Image source: http://ww1.microchip.com/downloads/en/DeviceDoc/30575A.pdf

Reliapro 39BYG001-R (5V, 1A)• 5V power supply, no need for an extra regulator

• 1.8° step angle – small steps for fine tuned board control without the need to add gears

• 2 phases – compatible with most stepper motor controller ICs

Motor Choice

Image source: http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_237490_-1

Raspberry Pi• Many configuration options for changing settings without

reprogramming microcontroller

• Low cost with large amounts of documentation/resources

• Easy to prototype and test without the microcontroller

WiFi Interface Selection

Image source: http://www.geeky-gadgets.com/wp-content/uploads/2012/07/Raspberry-Pi2.jpg

Packaging Design- Stock

Packaging Design- Modified

Schematic/Theory of Operation- Overview

Schematic/Theory of Operation- Power Supply

LM2576 Step-down (buck) switching regulator

Schematic/Theory of Operation- Stepper Driver

Schematic/Theory of Operation- Headers

PCB Layout- Overview

PCB Layout- Power Supply

PCB Layout- Stepper Driver

PCB Layout- Headers

Software Design/Development Status

• Microcontroller: prototyping on development board, several on-chip peripherals functioning.

• Microcontroller works as a polling loop that waits on packets from the Raspberry Pi

• Raspberry Pi: Server code functioning, receiving packets from iPhone in 1.66 ms. Wireless is set up.

• iPhone: Sending data to Raspberry Pi successfully. App also grabs rotation degree from internal accelerometer and gyroscope.

PIC Microcontroller Software Flowchart

• Week 8 – Program RaspberryPi, Formal Design Review

• Week 9 – Finalize PCB, Order all remaining parts, Software development (ongoing), Prototype power supply, Proof of Parts

• Week 10 – Spring Break, PCB manufactured

• Week 11 – Populate PCB in units, burn-in power supply, Software Design Narrative

• Week 12 – Debug Hardware, Program microcontroller, Attach sensors & motors to chassis, Patent Liability Analysis

• Week 13 – Debug Microcontroller, Finalize iPhone application, Develop control algorithms, Reliability & Safety Analysis

• Week 14 – Debug iPhone app, Debug iPhone -> RaspberryPi -> Microcontroller communication chain, Ethical & Environmental Impact Analysis

• Week 15 – Debug, Documentation, Finalize packaging, User Manual

• Week 16 – Debug, Prepare for PSSC Demonstration

Project Completion Timeline

Questions?