Transcript Slide 1

Senior Project – Computer Engineering - 2008
Integrated Workout Shoe
Peter Katlic
Advisor – Prof. Cotter
Abstract
This workout device measures distance, time, and pace for a walk or run. By integrating the design with a shoe there is no need for a user to
carry a separate device. Based on measurements from an accelerometer, the unit is designed to be low in cost, provide accurate measurements,
and is simple enough to replace or update. Necessary data can be viewed on the device while more specific data can be viewed on a computer,
catering to different users.
A microcontroller provides a timer and method for storing captured data from the accelerometer. This accelerometer reading is converted to
distance by timing each stride. The final unit, attached to the tongue of a shoe, is controlled via buttons for on/off, start/pause, and reset functions of
the device. The total time, total distance, and average pace can be viewed on a built-in display.
Goals
Produce a device that meets the following criteria:
- Attached to or integrated into a shoe
- Maximum cost of $50
- Record time, pace, distance
- Measure distance within 10% error
One full stride (measured by device)
Design
Silicon Labs
C8051F330
Microcontroller
Analog Devices
ADXL321
Accelerometer
Physical Interface:
Tactile Switches
Lumex Multiplexed
7-Segment Display
Development:
Consisting of an 8051 microcontroller with a 2-axis accelerometer
and switches for input, and a 7-segment display for output the
development device simulates the proposed small-scale final
design.
Final Version:
The reduced version will be made up of similar components, using
single chips instead of development boards so that it fits within the
proposed dimensions.
Basic Operation:
- wait until the start/stop button is pressed
- start the timer
- get input from the accelerometer and detecting a stride
- update running total of distance based on stride rate
- store total distance for every minute
- wait until the start/stop button is pressed
Development Design
Final Design Schematic
Results
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Development Design (completed)
8051 microcontroller development kit connected to a breadboard containing an
accelerometer development board and display.
Timer is started and displayed when user presses start button.
A stride is registered when a minimum accelerometer voltage is detected. This
occurs when the foot is farthest back in the stride.
The distance is updated based on the ratio of strides to time. A walking stride speed
is less than a running stride, enabling the differentiation of each type.
Distance is displayed when user presses stop button.
Close to 100% stride detection accuracy. Based on this the distance calculation
should be similar, but the lack of portability hinders real-world testing.
Final Design (in progress)
Scaled down in size by using single chips for 8051 and accelerometer.
Circuit schematic completed.
Circuit board incomplete.
Accuracy of distance measurement calculated by testing, should be similar to that of
the development device.
Total part cost of $30.
Final Design Board