Constructing an Earthquake Seismometer and Early Warning System Vardo Barsegyan, Sylvia Dhimdis, Matthew Ferrer, Dragos Guta, Jaesoon Lee, Arnold Martinez, Kenneth Moreno, Annie Norm, Lorenzo Rulli, Bryan Sanchez
Presentation Overview Motivation Background: Seismology Design and Construction of the Seismometer Warning System Demonstration Summary June 22, 2012SITE Seismometer2
Earthquakes 500,000 deaths in past 5 years Injuries Homeless families Japan 9.0: Over $300 Billion June 22, 2012SITE Seismometer3
We can not predict earthquakes. But we can give early warning... June 22, 2012SITE Seismometer4
What is an Earthquake? June 22, 2012SITE Seismometer5
Body Waves June 22, 2012SITE Seismometer6
Propagation of Seismic Waves June 22, 2012SITE Seismometer7
Seismogram June 22, 2012SITE Seismometer8 Minimum Warning Time
How Can We Detect These Earthquakes? June 22, 2012SITE Seismometer9
Principles Applied Newton’s Second Law Hugyen’s Law Faraday’s Law Ohm’s Law Damping/Resistance Amplification Digitization F=ma June 22, 2012SITE Seismometer10
Field Trip Cal Tech Seismology Lab Media Center San Andreas Fault June 22, 2012SITE Seismometer11
System Overview June 22, 2012SITE Seismometer12
Building the Sensor June 22, 2012SITE Seismometer13
Old Seismograph June 22, 2012SITE Seismometer14
Building the Sensor Works as the mass of the pendulum Choosing the number of turns of the coil – – More turns equals more voltage but harder to damp June 22, 2012SITE Seismometer15
Building the Sensor Works as the “paper” of the sensor June 22, 2012SITE Seismometer16
Building the Sensor Frequencies of P and S waves: 0.8 to 4 Hertz T = 1/f Length of the pendulum Θ T T H June 22, 2012SITE Seismometer17
Building the Sensor June 22, 2012SITE Seismometer18 Pendulum Sensor Coil Magnet
Amplifier Voltage from background motion is ~.5µV Need at least 10 mV to display clearly Voltage(out)=Gain*Voltage(in) Gain ≈ 20,000
LabVIEW June 22, 2012SITE Seismometer20
LabVIEW June 22, 2012SITE Seismometer21
DEMONSTRATION June 22, 2012SITE Seismometer22
Problems False alarms from human movement in lab Learning lab view difficult Need faster Computers June 22, 2012SITE Seismometer23
Accomplishments/Summary Designed and built two seismometers capable of detecting ground motion down to 0.5µm per second Designed and built one node of a complete earthquake alert system Programmed seismometer data recording and retrieval system Reviewed the concepts from math, physics, geology, computer science and engineering needed for the project June 22, 2012SITE Seismometer24
QUESTIONS? June 22, 2012SITE Seismometer25