Integrated Workout Shoe Peter Katlic Advisor: Shane Cotter

Current Offerings – Step Counter Uses internal switch to count “steps” Simple design Small size Low cost($10-$20) Accuracy(up to 50% error rate) Single user

Current Offerings - GPS Garmin Forerunner Uses GPS signals to record waypoints  distance Accuracy(1-5% error rate) Ease of use Multiple users Cost($120-$330) Loss of signal under tree cover Bulky design

Current Offerings - Accelerometer Apple Nike + iPod Uses accelerometer to measure acceleration  distance Accuracy(up to 10% error rate) Ease of use Multiple users Cost($30) (factoring in iPod($150-$350)) Reliance on iPod

Purpose Current offerings are extremes Create product in between others Combine benefits of each design

Goals Reached Produced a device that meets the following criteria: -Able to be attached to shoe tongue -Part cost of $30 -Records time and distance on device -Registers strides with close to 100% accuracy -Measures distance with 90% projected accuracy -Online workout log

Design Choices 2-axis vs. 3-axis accelerometer - no need for z-axis measurements Microcontroller (C8051F330) - small form factor - ADC - adequate RAM - sufficient I/O pins

Development Design Silicon Labs C8051FX20- TB microcontroller development board Analog Devices ADXL321EB-ND accelerometer development board Lumex LDQ-M284RI multiplexed display

Final Design (EAGLE) Circuit Schematic Board Layout

Components Serpac CA-10 waterproof enclosure Silicon Labs C8051F330-GM microcontroller Analog Devices ADXL321JCP accelerometer Lumex LDQ-M284RI multiplexed display

Input/Output Silicon Labs C8051F330 Microcontroller Analog Devices ADXL321 Accelerometer Physical Interface: Tactile Switches Lumex Multiplexed 7-Segment Display

Implementation Timer0seconds Timer3sampling rate ADC0getting input at 100Hz Port2display segments Port4display digit

Implementation Start/stop is pressed  timing begins, sampling begins, display time Stride is detected  calculate stride/second rate and update distance Every minute  store total distance in array Start/stop is pressed  timing stops, sampling stops, display distance

Testing – Phase 1 Development Device Accelerometer data range Data capture on 8051 Accurate stride detection Simple trials Axis0°-90°90° Y1.256V V V 2168 X1.217V1.172V1.278V At 2.441V

Testing – Phase 2 Final Device Adjust code for new platform Test walks/runs Known pace testing Calibration

Online Workout Log PHP with SQL database Multiple users Store workouts Graph workouts View workouts by date or user

Future Goals/Improvements Finish standalone device Integrate device into shoe Transfer data to computer and workout log

Questions Acknowledgements:James Hedrick