Mountain Bike Rallying SDII Final Presentation

November 25, 2008

Team Members

Frank HollandFirmwarePCB DesignPackaging

Michael VanJava GUI CodingPackaging

Andrew ThigpenJava GUI coding

Firmware RefinementPackaging

Overview• Background• Problem• Solution• Constraints

• Practical• Technical

• Testing• Packaging

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

Goal Time

Current TimeDistance

Battery Indicator

GPS Signal

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.

Battery Life Test

• With typical backlight usage:

• approximately 10 hours

Compatibility TestWindows Vista

Compatibility TestMac OSX Leopard

Compatibility TestUbuntu 7.10

Communication Test• Transferred 180

waypoint course to device

Acknowledgement of received waypoint from device

Console Output: Oscilloscope:

GPS Accuracy Test

Benchmark

Tau Beta Phi 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

System Test

• Downloaded event data

System Test

Timing Accuracy Test

• Used an external source

• Compared the times

Packaging - EnclosureEnclosure box w/ 4

AA batteries

Holds all essential components inside and keeps unwanted things outside

Protective boot custom made for the enclosure

Prevents package from breaking

Packaging – Outer Layout

Calipers to measure dimensions

Microsoft Visio to design the layout

Laser cutter to achieve custom fitting holes

PCB Breakdown15 capacitors &

resistors

PSoC microcontroller

EEPROM

Maxim RS232 serial voltage translator

Voltage regulator

Pin Header

Packaging – GPS/PCB

Used insulated hex stand-off

custom cut to fit corner slot of GPS unit

glued to bottom of GPS unit and PCB

Packaging – Inner Layout

LCD glued to top of enclosure

Sits on top of the battery

PCB mounted on top of GPS unit

Shortage clearance

Wiring fits in gap

PackagedSize 4.94 x 2.75 x 1.27"

Weighing in at 13.30 oz

Bill of MaterialsPart Price

PCB $26.40

Capacitors & Resistors $0.83

Integrated Circuits $8.45

LCD $10.51

GPS unit & antenna $84.99

Enclosure & Boot $9.68

Miscellaneous – Transistor/Button/DIP/Header

$4.22

Total $145.32

Questions?