Mountain Bike Rallying SDII Mid-Term Presentation

September 30, 2008

Team Members

Frank HollandFirmwarePCB DesignPackaging

Michael VanJava GUI CodingPackaging

Andrew ThigpenJava GUI coding

Firmware RefinementPackaging

Overview• Background• Problem• Solution• Constraints

• Practical• Technical

• Refinements• Packaging• Testing

Background

• Car Rally

• Geocaching

Problem

• Bike rider needs a navigator

• Current GPS units are not suitable for this sport

Solution

Practical ConstraintSustainability

• Ruggedness

• Must be able to withstand a drop from 3 feet

Practical ConstraintEnvironmental

• Operating Conditions

• Must be water resistant

• Must withstand temperatures from -20° to 43°C (-4° to 110°F)

Technical Constraints

• Tracking Accuracy

• The GPS must have an accuracy of 5 meters or less.

• Battery Life

• The overall product must have at least 6 hours of continuous battery life.

Technical Constraints• Display Size

• The display size must be able to hold a minimum of 74 characters on the screen.

• Example:

Current GPS

Next GPS

Current Time

Goal Time

Distance

Technical Constraints

• Product Size

• The product size must 3” x 6” x 3” or less.

• Product Weight

• The overall product must be less than 2 lbs.

Progress• End of Spring Semester

• Very simple device

• One mode of operation once turned on

• Limited display of information

Progress• Currently

• Graphics

• Menu-based operation

• Variable width characters for more information on the screen

Progress• Two modes of operation

• Transfer Mode

• Race Mode

• GPS Status Icon

• Battery Level Icon

Progress• Helpful dialogs to better inform user

• Labels provide more information about waypoints

• Time flashes to indicate goal approaching

Progress• I2C EEPROM

• Transfer up to 10 courses

• GPS data is saved for entire course

Progress

Map of Recorded GPS Data

Schematic

PCB Layout

Packaging• Plastic enclosure

• Built-in 4AA holder

• Available protective “boot” for increased ruggedness

• Fits size constraint

• 4.94 x 2.75 x 0.94"

Tests

•Battery life with backlight

•Size meeting with product specification

•Compatibility across different platforms

Battery Life Test

•Without LCD backlight

• approximately 10 hours

•With LCD backlight

• approximately 8 hours

Size Test

•Size of Enclosure

Compatibility TestWindows Vista

Compatibility TestMac OSX Leopard

Compatibility TestUbuntu 7.10

Results

Tests Results

Battery life with backlight Pass

Size compared to product specification

Pass

Software Compatibility Pass

More Tests

•Communication between device and computer

•System custom course

•GPS accuracy

Communication Test

• Transferred 180 waypoint course to device

Acknowledgement of received waypoint from device

Console Output: Oscilloscope:

System Test

• Downloaded event data

GPS Accuracy Test

•Benchmark

•Tau Beta Pi Monument

•Actual Coordinate

• N 33 27.260 W 088 47.320

•Measured Coordinate

• N 33 27.2596 W 088 47.3201

•Difference

• 0.7590 meters

More Results

Tests Results

Communication Pass

System Pass

GPS Accuracy Pass

Internal Test•Clock

•Signal Strength

Physical Test

•Weight

•Ruggedness

•Water resistance

Questions?