a paper from Mobisys 2014

1. An Energy Harvesting
Wearable Ring Platform for
Gesture Input on Surfaces
B00902069 傅蕎

2. Problem
• To interact with mobile devices on-the-go
• Glasses, wrist band, watch not good
• User have to practice
• Environment limits
• Too heavy processing, power hungry
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3. Related work
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4. Ring!!
• Wearable
• Detect finger motion on
arbitrary surfaces
• Transmit wirelessly
• Identify 23 gestures
• No explicit user training
• Energy harvesting from
NFC-enabled phone
• 10 hr 2Hz interaction
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5. Design
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6. Gestures
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7. Surface detection
• Arbitrary, un-instrumented surfaces
• Pressured-based touch detection
• Audio-based motion detection
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8. Surface detection - touch
• Pressured-based
• When touch or curl,
stiffen and move laterally
• Force sensing resistor
on inner wall of ring
• Consume less power
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9. Surface detection - motion
• Audio-based
• Friction between fingers and surfaces
• Function of finger motion speed,
and properties of the surface
• Noise
• Use band-pass filter
• They use common office paper
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10. Gesture classification
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11. Energy harvesting
• 10mAh battery capacity
• NFC-enabled phone
• RFID is a type of NFC
• Coil loop around ring band
• Maximize the size
• Position C best
• Over 5% capacity is available
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12. Evaluation
• SVM
• More data, more accurate
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13. Future work
• Wireless transmission no detect or recover from
packet loss or error
• Improve classification accuracy
• Improve noise resilience
• Larger variety of surfaces
• Lack of feedback
• Larger amount of training data
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14. Question?
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15. Thanks!:D
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