Acoustic Fossil Imaging

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Acoustic Fossil Imaging

• by
• Matt Kaiser John Lewis
• Advised by Dr. James H. Irwin Mr. José Sánchez

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Outline
Matt Kaiser John Lewis
-Project Summary -Functional Description -References -Parts List -Schedule -System Level Block Diagram -Sub-System Level Block Diagrams -Specification Sheet -User Interface
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Project Summary

• Goal Image Fossils Buried in Rock
• Major Components Ultrasonic Sensor, Data
  Acquisition, and PC
• Signal Processing in MATLAB
• Data Acquisition with Tektronix TDS3012B escope

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System Block Diagram
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Data Acquisition
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Overall Block Diagram
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Sensor Block Diagram

• Acoustic Sensor
• Description A device that sends a burst of 16
  50kHz acoustical pulses
• Acoustic Foam
• Description The acoustical foam narrows the
  dispersion angle of the sensor to provide more
  accurate results

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Oscilloscope Block Diagram

• Oscilloscope
• Description The oscilloscope provides a means to
  view the data graphically
• Format Output
• Description This allows the graphical data to be
  put into a form that can be imported to a PC with
  MATLAB

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Signal Processing

• PC with MATLAB
• Description The signal processing will allow the
  user to see the object in three dimensions, and
  will give other useful data about the object
  (e.g. length, width, and height)

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Software Flow Chart

• Import Data
• This converts the data into a useable form for
  MATLAB manipulation
• Correlate Data
• This allows multiple echoes contained in each
  other to be determined
• Dimension Determination
• Using time delays the dimensions of an object can
  be determined
• 3-D Plot
• This allows the user to view a specific object in
  3-D

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User Interface

• Move Sensor by Hand
• Acquire Data with Oscilloscope
• Run MATLAB M-File

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Specifications
Parameter Min Typ Max Units
Power Supply Voltage 4.5 5 6.8 V
Input Frequency - 10 - Hz
Input Voltage 0 - 4 V
Transmit Frequency - 49.4 - kHz
Transmit Pulses - 16 - -
Transmit Sensitivity 110 - - dB
Receive Frequency -42 - - dB
Operating Temperature 0 - 40 C
Operating Distances 6 - 35 ft
Vertical Directivity Pattern 0 - 60
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Parts List

• Ultrasonic Transducer
• Tektronix Oscilloscope
• HP Single Power Supply
• Krohn-Hite Function Generator
• PC
• Chips

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References

• Acoustic imaging The reconstruction of
  underwater objects, IEEE Visualization, 1991, p.
  94-101, ISBN 0-8186-2245-8
• Brunner, Eberhard, Ultrasound System
  Considerations and Their Impact on Front-End
  Components, Analog Devices, 2002
• Case study Visualization of 3-D ultrasonic data,
  IEEE Visualization, 1994, p. 369-373, ISBN
  1070-2385

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Schedule
Date Planned Work
January 27 Implement New Sensor
February 3 Work on Better Test Platform and Sensor Hardware
February 10 Acquire Data and Process
February 17 Work on More Complex Calculation Routines
February 24 Attempt to Image Objects Buried with Other Objects
March 2 Continue Complex Imaging
March 9 Implement More Sensors if Necessary
March 16 Spring Break
March 23 Testing
March 30 Testing
April 6 Final Software and Hardware Implementation Testing
April 13 Make Adjustments to Improve System
April 20 Prepare for Expo
April 27 Prepare Final Presentation
May 4 Finishing Touches on Documentation
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Questions?