how to make a motion tracking device
TRANSCRIPT
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Confidential
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How to make a motion tracking deviceMykola ShatokhinSoftware Engineer15.09.2016
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Instabeat
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1. Wearable devices 2. Device designing3. Data analyzing 4. Gotchas5. Summary
Agenda
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Wearable devices
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Device designing
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• Idea• Sensors and mount place• Collecting data• Analyzing algorithm• Related software
Device designing
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Mount position
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• Prepare protocol• Ask athletes to help• Make video
Collecting data
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Don’t be a racist
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Annotating
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Data analyzing
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Accelerometer
Gyroscope
Raw data
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Sliding window
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Where:
n – window size,
x – signal values in current window,
μ – window mean value.
Energy
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Accelerometer
Gyroscope
Energy
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Where:
n – axis count,
w – weight coefficient,
e – energy value.
Weighted energy
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Weighted energy
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Accelerometer axises
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Energy + acceleration mean (scaled amplitude)
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Signal smoothing
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Where,
n – filtering window size,
m – filtered value index,
x – signal value.
Simple Moving Average filter
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Signal smoothing
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Smoothed energy and acceleration
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Decision boundary
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Styles
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• Simplicity• Speed• Real time processing
Advantages
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• Low accuracy
Disadvantages
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• Sleep tracking• Brain-Computer interface• Games
Alternative usage
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Sleep tracking
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Brain-Computer interface
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Games
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Gotchas
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• Calibration• Data transmission• Stability
Gotchas
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Why C++?
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Summary
