Acoustic EMG System

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Acoustic / EMG System

• for the Analysis of
• Food Texture
• 2005 AGCO National Student Design Competition
• By Brent Jessop
• Krista Sider
• Tom Lee
• Advisor Dr. G. Mittal

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Design Inspiration

• Co-op Job
• Hotdog Texture
• Texture Profile Analysis (TPA)
• Human Perception of Food?
• Human Testing
• Unbiased?
• Provide an Alternative Method

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Constraints

• Measure the Human Perception of Food Texture
• Human Testing Approval
• Subject Safety

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Criteria

• Physical Interference with Mastication
• Subject Awareness of Mastication
• Quality of Measurement of the Human Perception of
  Food Texture
• Cost
• Environmental Impact
• Complexity of Use

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Design Alternatives

• Three Design Alternatives
• Pressure Sensors Mounted within a Modified
  Retainer
• Video Tracer System
• Acoustic / EMG System

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Acoustic / EMG System

• Electromyographic (EMG) Analysis
• Electrodes pick up nerve impulses signalling the
  motor units of muscles
• Measures strength of muscle contractions
• EMG data used to characterize food texture
• Acoustic Analysis
• Frequencies of sound correlated to certain food
  texture
• Textural differences can be analyzed

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Acoustic / EMG System
EMG electrodes
Sound Dampening Headset
Ear clip and Microphone
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Acoustic / EMG System

• Why it is Better?
• Interference with Mastication
• Subject Awareness of Mastication
• Quality of Measurements
• Relative Simplicity of Use

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System Testing

• Cheese-Celery-Carrot Sticks
• Pringles-Sun Chips
• Gummy Bears-Nibs

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Results
EMG
Acoustic
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Results
Maximum Signal
Total Accumulated Signal

Normalized Signal (Vs/Vmax )
Vmax per subject
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Results

• Average EMG Maximum Signal

n4
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Results

• Average Acoustic Maximum Signal

n4
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Results

• Average EMG Total Accumulative Power

n4
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Results

• Average Acoustic Total Accumulative Power

n4
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Results

• Similar Trends Between Subjects

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Recommendations

• Further Data Analysis
• Number of Chews
• Chewing Rate
• Bite Decay
• Fast Fourier Transforms

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Recommendations

• Improve Headset Comfort
• Larger Population
• Sensitivity Analysis
• Correlate to Traditional Methods
• Acoustic System Only

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Conclusion

• Distinguish Between Food Texture
• Repeatable, Quantitative and Unbiased Measurement
• Represents the Human Perception of Food Texture
  during Mastication

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Acknowledgements

• Special Thanks to
• Dr. G. Mittal for his Guidance and Support
• School of Engineering at the University of Guelph
• Dr. Oliver, Dr. Davidson, Greg Northy, Dr. Zhao,
  Allan Miller and Bill Verspagen

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Questions
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(No Transcript)
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Acoustic / EMG System