SoQr: Sonical Quantifying the Content Level inside
ContainersMingming Fan, Khai N. Truong
UbiComp ‘15
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Presenter: Ta Duc Tung @AKG - The University of Tokyo
Outline• Introduction
• Related Works
• Theory of Operation
• System Design + Model Training
• Evaluation
• Practical Issues2
Introduction
Automate?3
Introduction
How much … is left? Milk, Juice
Washing Detergent
Eggs, Rice
…
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Related Works
• Capacitive sensing
• Load sensing
• Camera sensing
• Electromagnetic Wave based sensing
• Acoustic sensing (time-of-flight)
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Theory of OperationImpulse Response Analysis
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System Design
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System Design
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Probing sound: 20Hz~20KHz sine wave
Record: 44.1KHz, 16 bits
System Design
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Model Training
• Data collection• 0.01s sweep sound
• 1.01s response recording
• 100 samples for each level
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Model Training
• Feature• Mel-Frequency Cepstral Coefficients - MFCCs
• Usually used in Speech Recognition
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Model Training
• Model Learning - libSVM• Classification - Supported Vector Machines
• Regression - Supported Vector Regression
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Evaluation
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• Package:
• Material
• Is deformable?
• Shapes - Closable?
• Content:
• Type: liquid, solid, gel
• Density
Evaluation
• Most controlled environment - content at bottom
• Classification: overall F-Measure = 0.969
• Regression: mean absolute error = 0.0514
Evaluation• Most controlled environment - Eggs Package
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Eggs Package
Evaluation
• Usage scenarios - Storing Places
• Train in refrigerator - Test on kitchen top
• Train on kitchen top - Test in refrigerator
• Overall Precision, Recall, F-Measure > 0.9
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Evaluation• Usage scenarios - Container’s Orientation
• Separated training dataset
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Stand-Up vs
Laid Down
Evaluation• Usage scenarios - Container’s Orientation
• Combined training dataset
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Stand-Up vs
Laid Down
Evaluation• Usage scenarios - Deformable? Closable
• Deformable products
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Potato Bag Opened - Clipped - Tied
Evaluation• Usage scenarios - Deformable? Closable
• Solid products - Closable
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Evaluation
• Most controlled environment: GOOD
• Different storing places: GOOD
• Solid closable package: GOOD
• Different orientation: BAD
• Deformable package: BAD
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Practical Issues
• Build prediction model for each product
• Sensor installing place
• Unconstrained context
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Conclusion
• Small size sensor for content level sensing
• F-Measure > 0.96
• Sensing in different contexts
• Storing place, Orientation
• Rigid container
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