Earthquake Detector Using the Michelson Interferometer The Mid-South Annual Engineering and Sciences Conference MAESC 2006 Memphis, Tennessee Haoyan Bill Lan March 31, 2006

Deep underground Every Day

America's most destructive earthquakes since the turn of the 20th century: Last Decade

People Are at Risk Researches need to be done there are 70,000 buildings in state of California alone that could sustain major quake damage Experts predict there will be a major earthquake in state of California before year 2024

For those who lives there It would be nice…. If……

Earthquake Detector Prototype Michelson Interferometer Optical Power Meter Analog to Digital Interface and LED Displays UP3 Board with a Cyclone Microprocessor

Project Concept Michelson Interferometer Light Intensity Measuring Device Analog to digital interface Major part of the project Central processing unit UP3 board (Quartus II) Alarm System and back up power supply 4 Digits 7-Segment LED Display

Screen Matrix for Different Needs

3D View of an Interferometer Sensor of Light Intensity Measuring Device Move Mirror#1 to cause the fringe movement He Ne Laser Beam Generator Beam Splitter Mirror#2 Stationary Bright Fringe Dark Fringe Dispersion Lens

How does it work? Mirror#2 Stationary Mirror#1 Moving

Bright Fringe Dark Fringe

Sensor of Optical Power Meter Movement of Mirror#1 generates fringe movement Dial for Moving Mirror

Need fringes number to calculate the wavelength Fringe movements not be counted using naked eyes The sinusoidal wave has a frequency approx. at 100Hz

The way to measure the spectral of the light is where d is the distance M1 has been moved and n is the number of the fringes and Lambda is the wavelength of the laser beam.

How does this work? a single tap on the table will cause rapid movement of the fringes this property can be used to detect a potential earthquake

Sinusoidal wave from the optical power meter Output wave form goes into the UP3 board Offset Voltage

Design of an Analog to Digital Interface Adjustable offset voltage TTL output

Project Concept Michelson Interferometer Light Intensity Measuring Device Analog to digital interface Major part of the project Central processing unit UP3 board (Quartus II) Alarm System and back up power supply 4 Digits 7-Segment LED Display

Altera UP3 board is setup in the lab Output to 4-digits Displays Input from Analog to Digital Interface Microprocessor is Programmed via a PC

Circuit Design using Quartus Input from Analog to Digital Interface Output of the Unit Digit Output of the Tenth Digit Output of the Hundredth Digit Output of the Thousandth Digit

A chip Input Decade Counter Decoder

LED Digit Displays 7-Seg LED Display

Prototype Testing Simulate an earthquake Tester tap table with his/her finger

Since Lambda for a He-Ne laser beam is 632nm For each fringes (n=1), we are moving Theoretically we are detecting vibration on 1/3um scale

Put 1/3um into a prospective scale Vibration of 1/3 of this Scale Human hair avg. 65um in Diameter

Prototype Estimated Cost Interferometer $700 Light intensity detector $150 Quartus II and software $300 Other parts and hardware $50 Total cost $1200

Estimated Production Cost Interferometer $100 Light intensity detector $50 Burn-in Chips $10 Other parts and hardware $50 Total cost ~$210 Instead of the $300 UP3 Board

References ml quake8sep08,0, story ents/unv-students.html stronomy/interferometry_101.html

Questions And Comments?

Prototype Testing Continues Simulation of a fire disaster has been conducted as well A pressure changing device has been used