quartz resonator technology - paroscientific, inc. - continued/quartz... · 2017-02-28 ·...

Paroscientific, Inc.Paroscientific, Inc.

Quartz Resonator TechnologyQuartz Resonator Technology

Prepared by:Paroscientific, Inc.

Quartz Seismic Sensors, Inc.


IntroductionIntroduction

The widespread use of digital computers and digital control systems have generated a need for high accuracy, inherently digital sensors.We will discuss the design, construction, performance, and applications of resonant quartz crystal transducers.These quartz sensors are used to accurately measure:

Pressure Acceleration Angular Rate (Gyros) Temperature Weight (Scales) Force (Load Cells)


Quartz Crystal Resonators ConvertAnalog Forces to Digital Outputswith Parts per Billion Resolution


Material Properties and Characteristics Material Properties and Characteristics of Quartz Sensorsof Quartz Sensors

Piezoelectric [pressure-charge generation]Anisotropic [direction-dependent]– Elastic Modulus– Piezoelectric Constants– Coefficient of Thermal Expansion– Optical Index of Refraction– Velocity of Propagation– Hardness– Solubility [etch rate]– Thermal and Electrical conductivity


Advantages of Quartz Resonant Sensors•

High Resolution More precise measurements can be made in the time domain than the analog domain.

•

Excellent Accuracy The quartz crystal sensors have superior elastic properties resulting in excellent repeatability and low hysteresis.

•

Long Term Stability Quartz crystals are very stable and are commonly used as frequency standards in counter-timers, clocks , and communication systems.

•

Low Power Consumption•

Low Temperature Sensitivity•

Low Susceptibility to Interference•

Easy to Transmit Over Long Distances•

Easy to Interface With Counter-Timers, Telemetry, and Digital Computer Systems


Design of Quartz Resonant SensorsDesign of Quartz Resonant Sensors

Single Beam Force SensorsDouble-Ended Tuning Fork Force SensorsTorsional Temperature Sensors


Single Beam Force Sensor

Flexure ReliefIsolator Spring Input Force

Vibrating Beam

(Electrodes on Both Sides)

Isolator Mass

Mounting Surface


Single Beam Force Sensor


Double-Ended Tuning Fork Force Sensors

Electrical Excitation Pads

Surface Electrodes

Dual Tine Resonators

Mounting Pad

Applied Load


Double-Ended Tuning Fork Force Sensors


0 Full Scale Compression

28

26

24

22

Full Scale Tension

10% Change in Period with Full Scale Load

Resonant Period (microseconds)

Output Period vs. Force

Presenter

Presentation Notes

The high Q resonant frequency, like that of a violin string, is a function of the applied load - increasing with tension and decreasing with compression. Usually the output signal gates a high frequency clock and the period output is measured. The change in period output with full scale load is 10%.


Torsional Resonator Temperature Sensor

Nominal Period of Oscillation=5.8 microseconds

Nominal Temperature Sensitivity=45 ppm/0C

Electrical Excitation Pads

Dual Torsionally Oscillating Tines

Mounting Pad


Wafer of Temperature Sensors


Design of TransducersDesign of Transducers

•

Temperature Sensors Using Strain•

Multi-Sensors (Angular Rate + Acceleration)

•

Load Cells & Scales•

Accelerometers & Seismometers

•

Pressure Transducers


Strain Sensitive Quartz Resonator

Base Material with Thermal Coefficient of Expansion Different than Quartz

Temperature Sensor Using Strain


Quartz Multi-Sensor (Acceleration &Angular Rate)

US Patent 6,595,054, Paros and Schaad,“Digital Angular Rate and Acceleration Sensor”


Load Cell

Applied Load

Resonator in Compression

Resonator in Tension


Load Cell Used in Scale


Commercial Quartz Scale


Accelerometer (Circa 1960’s)Vacuum Can

Flexure Hinge

Inertial Proof Mass

Quartz Resonator

Mounting Surface

Inertial Proof Mass

Flexure Hinge

Input Axis

Quartz Resonator


Quartz Resonator Accelerometer (Circa 1970’s)


Quartz Resonator Accelerometers (Circa 1980’s)


Quartz Triaxial AccelerometerQuartz Triaxial AccelerometerAn intrinsically digital, triaxial accelerometer with a full scale of ±3 g’s was developed with a dynamic range of 176 dB (to 5 nano-g’s) using readily available readout electronics. The dynamic range is at least an order of magnitude higher than existing products.

Other advantages include small size, low power, shock protection, and a suitable temperature range for oceanographic and seismic vault installations.

An intrinsically digital, triaxial accelerometer with a full scale of ±3 g’s was developed with a dynamic range of 176 dB (to 5 nano-g’s) using readily available readout electronics. The dynamic range is at least an order of magnitude higher than existing products.

Other advantages include small size, low power, shock protection, and a suitable temperature range for oceanographic and seismic vault installations.


Quartz Triaxial Accelerometer (Circa 2008)Quartz Triaxial Accelerometer (Circa 2008)

US Patent 6,826,960, Schaad and Paros,“Triaxial Acceleration Sensor”


Quartz Triaxial Accelerometer Quartz Triaxial Accelerometer

Acceleration Sensing Resonators

Temperature Sensing Resonators

Quad Oscillator3 Acceleration +1 Temperature

Counter & DigitalProcessing Electronics

Inertial Mass TriaxialMechanism


Quartz Crystal Resonator Pressure Transducers

Internal VacuumBalance Weight

Bourdon Tube

Quartz Crystal Resonator Force Sensor

Case

Quartz Resonator Temperature Sensor

BellowsPressure Input

Balance Weight

Quartz Crystal Resonator Force Sensor

Quartz Resonator Temperature Sensor

Input Pressure


Digiquartz® Barometer


Transducer Characteristics and Performance

• Static Error Band– Non-repeatability– Hysteresis– Conformance

• Environmental Errors– Temperature– Acceleration

• Long Term Stability• Nano-Resolution


Static Error BandStatic Error Band (Non(Non--Repeatability, Hysteresis, NonRepeatability, Hysteresis, Non--Conformance)Conformance)

-0.0100

-0.0080

-0.0060

-0.0040

-0.0020

0.0000

0.0020

0.0040

0.0060

0.0080

0.0100

600 700 800 900 1000 1100 1200

Pressure (hPa)

Err

or %

fs Up1

Down1

Up2

Down2


-0.03

-0.02

-0.01

0.00

0.01

0.02

0.03

-80 -60 -40 -20 0 20 40 60 80 100 120

Temperature (deg C)

Err

or %

full

scal

e

Zero

Mid-scale

Full-scale

Total Error Band (Over Temperature at Various Pressures)


Pressure Hysteresis Measurements on Twenty-Three Paroscientific Barometers

Number of Units

Pressure Hysteresis in Microbars

0-10 -5 5 10

Mean Hysteresis -1.3 Microbars


Long Term Stability Tests (21Long Term Stability Tests (21--Years)Years)

S/N 34264 Long-Term Stability

-0.3-0.2-0.10.00.10.20.3

1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013

hPa

Median Drift Rate = -6 ppm per year

S/N 37131 Long-Term Stability

-0.3-0.2-0.10.00.10.20.3

1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013

hPa


NanoNano--Resolution TechnologyResolution Technology

Inherently digital sensors based on quartz crystal technology are used extensively for environmental monitoring because of their high absolute accuracy and long-term stability

Many oceanic, atmospheric and seismic applications require broadband, high-resolution measurements of dynamic phenomena

Advances in counting circuitry and digital signal processing have improved the resolution of Quartz Crystal Resonator Sensors to a sensitivity of parts-per-billion over an extended spectrum

Inherently digital sensors based on quartz crystal technology are used extensively for environmental monitoring because of their high absolute accuracy and long-term stability

Many oceanic, atmospheric and seismic applications require broadband, high-resolution measurements of dynamic phenomena

Advances in counting circuitry and digital signal processing have improved the resolution of Quartz Crystal Resonator Sensors to a sensitivity of parts-per-billion over an extended spectrum


0 Full Scale Compression

28

26

24

22

Full Scale Tension

10% Change in Period with Full Scale Load

Resonant Period (microseconds)

Output Period vs. Force

Presenter

Presentation Notes

The high Q resonant frequency, like that of a violin string, is a function of the applied load - increasing with tension and decreasing with compression. Usually the output signal gates a high frequency clock and the period output is measured. The change in period output with full scale load is 10%.


Reciprocal Start-Stop Counting

Pressure Signal

Timebase Clock

Time N Periods

Time

τ=Sensor Output Period= 1/Resonant FrequencyN=Number of PeriodsTransducer period output, τ, gates a high frequency clock, fc

, for N periods and the clock pulses are counted.

(fc

)


Sampling Time=NτPeriod Resolution=+/-

1 Count/(Total Counts)=+/-

1 / (Nτ)(fc

) = +/-

1 / (Sampling Time) (fc

)

Force Resolution= +/-

10 / (Nτ)(fc

) (Only 10% of the counts are related to Force)

Example: If clock=20 MHz and sampling time=1 secondThen the Force Resolution=5x10-7

Full Scale

Pressure Signal

Timebase Clock

Time N Periods

Time


Linearization and Temperature Compensation

Force = C[1-

τ

02/ τ

2] [1-D(1-

τ

02/ τ

2)]τ

=Force Resonator Period Output

C=Scale Factor in Desired Engineering UnitsD=Linearization Coefficientτ

0

=Period Output at No Load (Force=0)U=(Temperature Sensor Period)-(Temperature Period at zero 0C)τ

0

= τ

1

+ τ

2

U+ τ

3

U2+ τ

4

U3+ τ

5

U4

C=C1

+C2

U+C3

U2

D=D1

+D2

UTemperature=Y1

U+Y2

U2+Y3

U3

(0C)


Intelligent Instrumentation

Multiplexer

Counter

Microprocessor

Shift Store Pass On

RS-232 & 485 Interface

EEPROM

EPROM

15 Mhz Clock

Transducer

Pressure Signal Temperature Signal

RS-232 &

RS-485 InRS-232 &

RS-485 Out


Nano-Resolution Counting TechniquesStart-Stop Reciprocal Counting:

Measure time with a high-speed clock for N signal periods.

Regression Counting:

Measure signal periods many times (over-sample) and apply a regression algorithm. This is a Finite-Impulse-Response (FIR) filter with up to 100 times higher sensitivity at 1 Hz sampling and Nano-Resolution is possible.

IIR Nano-Counting:

Uses a multi-stage Infinite-Impulse-Response (IIR) digital low- pass filter with each stage of the form:

wn

= α

zn

+ (1 –

α) wn-1

zn

Is the unfiltered period and wn

is the filtered period output after one filter stage.Alpha, α, is small and determines the frequency cutoff value of the low-pass filter.A 5-stage low-pass filter attenuates all values above the cutoff at -100 dB/decade.High-frequency signals are filtered (anti-aliasing filter) and Nano-Resolution is possible.


Start-Stop Method

-1000

100200300400500600700800

-1 0 1 2 3 4 5 6 7 8 9 10 11

N Periods

n Cl

ock

Coun

ts

Regression Method

-1000

100200300400500600700800

-1 0 1 2 3 4 5 6 7 8 9 10 11

N Periods

n Cl

ock

Coun

ts

Nano-Resolution withRegression (FIR) Counting

(FIR: Finite-Impulse-Response in Digital Signal Processing)

Start-stop method: Slope between endpoints determines sensor period.Regression counting: Many sub-samples, slope is least-squares regression fit. Statistical improvement is √(N/6). Nano-resolution (parts-per-billion) is possible.

Paroscientific, Inc.Paroscientific, Inc.DigiquartzDigiquartz®® Pressure InstrumentationPressure Instrumentation

0.0001

0.0010

0.0100

0.1000

1.0000

1.E+0 1.E+1 1.E+2 1.E+3 1.E+4 1.E+5 1.E+6 1.E+7 1.E+8 1.E+9

Record Length (seconds)

Stan

dard

Dev

iatio

n (P

a)Resolution Improvement with Nano-Counting

Reciprocal Start-Stop Counting Technique

Nano-Resolution With Advanced Counting Algorithms


Experimental IIR Nano-Counting Resolution

0.00001

0.0001

0.001

0.01

0.1

1

10

100

0.0001 0.001 0.01 0.1 1 10 100

Time Interval (seconds)

Pasc

al

One Nano-bar in one second


Ambient Barometric Infrasound SpectrumAnd Digiquartz Nano-Barometer Noise Floor

Day-long barometric data in Seattle (7/23/08)Green curve: Infrasound ambient background (no micro-baroms)Red curve: Instrument self-noise 7.2 E-7 Pa^2/Hz (-61 dB re: Pa^2/Hz)

Psi^2/Hz

Hz

Plot courtesy of Spahr Webb


Pacific Ocean Microbaroms Using IIR FilterPacific Ocean Microbaroms Using IIR Filter

Residual Noise Between Two Independent Barometers = 0.4 mPa


- Digiquartz Nano-Barometer Spectral Resolution -

- Bowman et al, SAIC, Infrasound Technology Workshop - Tokyo, Japan November 13-16, 2007

Digiquartz Nano-Barometer Spectral Resolution Superimposed on Infrasound Ambient Spectrum

Micro-barom Peak


Sakurajima EruptionThe infrasound measuring station is 987 km from the volcano. The estimated

travel time for the sound wave was 48 minutes.

1006.3

1006.35

1006.4

1006.45

1006.5

1006.55

1006.6

1006.65

1006.7

1006.75

1200 1400 1600 1800 2000 2200 2400

seconds after 10/3/09 8:00 UTC

hPa


-6

-4

-2

0

2

4

6

1950 2000 2050 2100 2150 2200seconds after 10/3/09 8:00 UTC

PaSakurajima Eruption

The amplitude was over 4 Pa at a distance of nearly 1000 km.


Infrasound Measurements with Paroscientific Nano-Resolution Barometers Space Shuttle Pressure Signal - April 20, 2010 - 5:00 to 6:10 PDT - Passband 0.1 to 5 Hz

0 1 2 3 4 5 6 7 8 9 10

minutes

1 Pa

per

trac

e


4/20/10 5:57:00 4/20/10 5:57:05 4/20/10 5:57:10 4/20/10 5:57:15 4/20/10 5:57:20 4/20/10 5:57:25 4/20/10 5:57:30

99464

99465

99466

99467

99468

99469

99470

99471

Absolute Pressure (Pascal)

Time (PDT)

Space Shuttle Pressure SignatureMeasured with Paroscientific Nano-Resolution BarometerSeattle, WA USA ‒

Location: 47 34 44 N 122 22 47 W


Digiquartz Depth Sensor Noise Floor

Vertical axis: Spectral density plot in psi2/Hz Horizontal axis: Frequency in HzGreen curve: Infrasound ambient background (measured with 7000 m depth sensor)Blue curve: Instrument self-noise (less than 0.14 Pa2/Hz)Noise floor of a 2000 m depth sensor is 0.01 Pa2/Hz

Plot courtesy of Spahr Webb


New Technologies forNew Technologies for Environmental MonitoringEnvironmental Monitoring

New Nano-Resolution Technologies offer unprecedented, cutting-edge, scientific and educational opportunities in the oceanic, atmospheric and seismic fields

Low-cost, multi-use, cross-disciplinary research of air-sea-land interactions can be accomplished by adding Nano-Resolution Sensors to existing networks

New environmental monitoring capabilities include measuring absolute barometric pressure fluctuations to nano-bars for infrasound detection, measuring water level fluctuations to microns with absolute, deep-sea depth sensors, and measuring acceleration and Earth's gravity to nano-g’s

New Nano-Resolution Technologies offer unprecedented, cutting-edge, scientific and educational opportunities in the oceanic, atmospheric and seismic fields

Low-cost, multi-use, cross-disciplinary research of air-sea-land interactions can be accomplished by adding Nano-Resolution Sensors to existing networks

New environmental monitoring capabilities include measuring absolute barometric pressure fluctuations to nano-bars for infrasound detection, measuring water level fluctuations to microns with absolute, deep-sea depth sensors, and measuring acceleration and Earth's gravity to nano-g’s


Application Areas for Quartz Sensors with NanoApplication Areas for Quartz Sensors with Nano--ResolutionResolution

AtmosphericAtmospheric••CTBT Nuclear Test MonitoringCTBT Nuclear Test Monitoring••ClimateClimate------SolarSolar--driven Atmospheric Tidesdriven Atmospheric Tides••WeatherWeather̶̶Pressure Fields and GPS MeteorologyPressure Fields and GPS Meteorology••Atmospheric Corrections to Seismic MeasurementsAtmospheric Corrections to Seismic Measurements••Infrasound (microbaroms, tornadoes, avalanches, earthquakes, volInfrasound (microbaroms, tornadoes, avalanches, earthquakes, volcanoes, bolides)canoes, bolides)•• Airport ApplicationsAirport Applications

••WindWind--Shear & WakeShear & Wake--TurbulenceTurbulence••Digital Altimeter Setting IndicatorsDigital Altimeter Setting Indicators••Air Data Test Sets and CalibratorsAir Data Test Sets and Calibrators

OceanicOceanic••CTDCTD’’ss, Tide gauges, & Profiling Systems, Tide gauges, & Profiling Systems••Inverted Echo Sounders, ROVInverted Echo Sounders, ROV’’s, & AUVs, & AUV’’ss••CoCo--locate with Ocean Bottom Seismometerslocate with Ocean Bottom Seismometers••Depth Sensors (tsunamis, subsidence, tectonic plate movement)Depth Sensors (tsunamis, subsidence, tectonic plate movement)••Replace Differential Pressure GaugesReplace Differential Pressure Gauges----Measure LongMeasure Long--period Infragravity Wavesperiod Infragravity Waves

SeismicSeismic••EarthquakesEarthquakes••Gravity SurveysGravity Surveys••Directional DrillingDirectional Drilling••Carbon Sequestration MonitoringCarbon Sequestration Monitoring


Photos and Diagrams courtesy of N.O.A.A.

Tsunami Warning System


Tsunami Detection (Earthquake Generated Tidal Waves) Improved Sensitivity of <0.1mm at Depths of 6000 meters


Comparison Comparison NanoNano--Resolution Depth SensorResolution Depth Sensor

/ BPR/ BPR

(with offset)(with offset)

1299.43

1299.44

1299.45

1299.46

1299.47

1299.48

1299.49

1299.50

1299.51

19:49 19:50 19:51 19:52 19:53 19:54 19:55 19:56 19:57 19:58 19:59 20:00 20:01

psi

Comparison NanoComparison Nano--Resolution Depth Sensor / Standard BPR Resolution Depth Sensor / Standard BPR


Co-located Depth Sensor andOcean Bottom Seismometer

Plot courtesy of Earl Davisand NEPTUNE -

Canada


Co-located Depth Sensor and Ocean Bottom Seismometer

Plot courtesy of Earl Davisand NEPTUNE -

Canada


Nano-resolution Depth Sensor & Land-based Seismometer Comparison

Plot courtesy of NOAA-PMEL


The Juan de Fuca Plate is bounded on the south and west by the Pacific Plate, and on the north and east by the North American Plate. A tectonic plate has three kinds of plate boundaries:

(1)

A spreading center ‒

The seafloor pulls apart at about 3 to 6 cm per year inducing very active volcanism ‒

the western boundary (Juan de Fuca Ridge) is of this type.

(2)

The eastern boundary is a subduction zone where the plate plunges beneath the over-riding North American Plate. The specific boundary is at the dark blue/light blue transition which is explicitly the plate to plate contact.

(3)

The third boundary is known as a Transform Fault, and the one on the south is called the Blanco Transform. The two plates slip past one another at about the same rate as the spreading rate and are characterized by frequent, small to medium sized earthquakes on a semi-continuous basis.

Ocean Observatory ProgramNext Generation of Scientific Discovery Across and Within Ocean Basins


Slide Courtesy of John Delaney

Ocean Observatory Program

The Ocean Observatory Program is planned to operate for the next

30 years. The Regional Cabled Observatory is the highest bandwidth portion of the entire program, and is designed to transform the way Ocean Science is done

The northern ring configuration (NEPTUNE Canada) is currently operational.


Slide Courtesy of John Delaney

Regional Scale Nodes 1 through 5 will address issues on the southern part. This system will deliver 10’s of KW of power and 10’s of Gb of bandwidth to each of the Primary Nodes. Each node may have hundreds, eventually thousands, of instrument packages. There is at least one node at each of the plate margins where plate dynamics are

most extreme. This will allow sustained studies of typical world-wide plate boundary environments.

Regional Cabled Observatory

Paroscientific, Inc.Paroscientific, Inc.DigiquartzDigiquartz®® Pressure InstrumentationPressure Instrumentation Slide Courtesy of John Delaney

The most vigorous methane venting is in the vicinity of Pinnacle, a carbonate deposit rising 50 meters above the seafloor. Sensors include depth sensors, seismometers, current meter-temperature sensor system, mass spectrometer, camera, fluid sampler and acoustic doppler current profiling sensor.

Paroscientific, Inc.Paroscientific, Inc.DigiquartzDigiquartz®® Pressure InstrumentationPressure Instrumentation Slide Courtesy of John Delaney

View from deep water at the site on Hydrate Ridge.

Pressure sensors will read out the depths of the winch package and the profiler package. The sensor packages can be controlled from land via fiber and will migrate up and down the cable. Far more sophisticated experiments will be explored with this infrastructure and the new Paroscientific Nano-Depth Sensors.


Nano-Resolution Barometers Co-located with GPS, Radar, and Cabled Systems

Co-locating Nano-Resolution Sensors at existing networks

provide low-cost, cross-disciplinary, multi-use, value-added enhancements to the established research, educational, and outreach infrastructures.

Accurate, stable, full-scale absolute, barometric data

can:Correct for atmospheric noise on seismic instrumentsProvide weather information (pressure fields and GPS-MET to determine precipitable water vapor for fog forecasts and flood warnings)

Provide climate information (solar-driven atmospheric tides)

Nano-Resolution measurements of atmospheric fluctuations (infrasound)

can:Perform nuclear monitoring for the CTBTTest for acoustic sea-air-land coupling interactions such as microbaroms, earthquakes, volcanoes, bolides, Earth's hum, and turbulence

Provide severe weather information for tornado and hurricane predictionsExtend the frequency response over a wider spectrum into deep infrasoundReplace microphones that can not make absolute measurements, do not have built-in, anti-aliasing software filters, and require special dynamic calibration equipment

Nano-Resolution Barometers Co-located with GPS, Radar, and Cabled Systems

Co-locating Nano-Resolution Sensors at existing networks

provide low-cost, cross-disciplinary, multi-use, value-added enhancements to the established research, educational, and outreach infrastructures.

Accurate, stable, full-scale absolute, barometric data

can:Correct for atmospheric noise on seismic instrumentsProvide weather information (pressure fields and GPS-MET to determine precipitable water vapor for fog forecasts and flood warnings)Provide climate information (solar-driven atmospheric tides)

Nano-Resolution measurements of atmospheric fluctuations (infrasound)

can:Perform nuclear monitoring for the CTBTTest for acoustic sea-air-land coupling interactions such as microbaroms, earthquakes, volcanoes, bolides, Earth's hum, and turbulenceProvide severe weather information for tornado and hurricane predictionsExtend the frequency response over a wider spectrum into deep infrasoundReplace microphones that can not make absolute measurements, do not have built-in, anti-aliasing software filters, and require special dynamic calibration equipment


GPS Meteorology

GPS Determination of Precipitable Water Vapor•

Measure Total Delay=Ionospheric + Neutral Delays

•

Ionospheric Delay (frequency dependent) determined by comparing L1 & L2 GPS signals

•

Neutral Delay=Wet Delay + Hydrostatic Delay (Barometric Pressure, Temperature, Humidity dependent)

•

Calculate Precipitable Water Vapor from Wet Delay


Atmospheric Noise MitigationAtmospheric Noise Mitigation

Local atmospheric pressure fluctuations are significant sources of noise in seismic data. Pressure changes associated with common atmospheric phenomena such as frontal passages, jet-stream passages, boundary-layer convection, and gravity waves can deform the ground that surrounds a seismometer to cause significant horizontal tilt noise. Other atmospheric influences include the gravitational effects of a variable weight of the column of air above the seismometer, vertical ground deformations, and possible buoyancy

effects. The reconstruction and elimination, in real time or post facto, of these atmospheric effects requires the monitoring of local pressure changes with collocated high-resolution, broadband barometers. The pressure-induced noise can be deterministically removed from the seismometer, strainmeter, and tiltmeter data to substantially increase the overall performance of the seismic sensor network.

Local atmospheric pressure fluctuations are significant sources of noise in seismic data. Pressure changes associated with common atmospheric phenomena such as frontal passages, jet-stream passages, boundary-layer convection, and gravity waves can deform the ground that surrounds a seismometer to cause significant horizontal tilt noise. Other atmospheric influences include the gravitational effects of a variable weight of the column of air above the seismometer, vertical ground deformations, and possible buoyancy

effects. The reconstruction and elimination, in real time or post facto, of these atmospheric effects requires the monitoring of local pressure changes with collocated high-resolution, broadband barometers. The pressure-induced noise can be deterministically removed from the seismometer, strainmeter, and tiltmeter data to substantially increase the overall performance of the seismic sensor network.


Atmospheric Tides at Harvard VaultAtmospheric Tides at Harvard VaultAndreas Muschinski analyzed a 15-day long series of pressure data acquired with Paroscientific Barometers at the Harvard Vault.

The solar atmospheric tides can be clearly seen in the frequency

spectrum of the pressure fluctuations. The dominant mechanism for solar tides is thermal expansion due to solar radiation.

The observed amplitudes are:12 hour tide amplitude--100 Pa 8 hour tide amplitude--40 Pa6 hour tide amplitude-----30 Pa 4 hour tide amplitude----8 Pa

We thank Robert Busby and John Collins of IRIS for conducting the tests and providing the data, Harvard University for use of their facility, equipment and seismic data, and Quanterra, Inc. for their collection, integration and installation assistance.

Andreas Muschinski analyzed a 15-day long series of pressure data acquired with Paroscientific Barometers at the Harvard Vault.

The solar atmospheric tides can be clearly seen in the frequency

spectrum of the pressure fluctuations. The dominant mechanism for solar tides is thermal expansion due to solar radiation.

The observed amplitudes are:12 hour tide amplitude--100 Pa 8 hour tide amplitude--40 Pa6 hour tide amplitude-----30 Pa 4 hour tide amplitude----8 Pa

We thank Robert Busby and John Collins of IRIS for conducting the tests and providing the data, Harvard University for use of their facility, equipment and seismic data, and Quanterra, Inc. for their collection, integration and installation assistance.


Atmospheric Tides at Harvard VaultAtmospheric Tides at Harvard Vault


Andreas Muschinski made a preliminary analysis of the GSN AMN0 (Albuquerque) pressure time series compiled by Tim Ahern and Rick Benson. The dataset, collected with a Paroscientific broadband barometer, contains about 200 million one-second samples of surface barometric pressure covering the 6-year period from January 2002 through April 2007. This first preliminary analysis considered the first 365 days from the second file with 31.5 million one-second samples (data points). A sequence of 52,560 (365 x 86,400/600) ten-minute averages (averages over 600 subsequent samples) and resulting periodogram were computed.

The solar tides reflect the Fourier components of the daily pressure signals associated with the daily temperature signals. The (solar) diurnal tide, the semidiurnal tide, the 8-h (1/3 day) tide, the 6-h (1/4 day) tide, and all the higher harmonics up to the 206-min tide (1/7 day) are resolved with an unprecedented signal-to-noise ratio. Also the 160-min tide (1/9 day) is visible. An estimate of 5 Pa (!) for the amplitude of the 6-h (1/4 day) tide was obtained. The amplitudes of the higher harmonics are even smaller.

Installation of state-of-the-art, broadband barometers on the EarthScope grid would dramatically improve our ability to monitor atmospheric tides and their seasonal variability, annual cycle, and possible long-term trends on regional and global scales. The resulting database would open new avenues for basic and applied research and would be useful for the improvement of numerical weather prediction (NWP) models, global circulation models (GCMs), andclimate system models (CSMs).

YearYear--long Atmospheric Tides at Albuquerquelong Atmospheric Tides at Albuquerque


We thank David Simpson, Tim Ahern, Rick Benson, Rick Aster, and their colleagues at IRIS, GSN, PASSCAL, and DMC for providing the data and format analysis techniques


Atlantic Ocean Microbaroms Using FIR Filters

73

CASA-Paroscientific Infrasound Networks Partnership

David McLaughlinUniversity of Massachusetts

College of Engineering

74

CASA mission: create value through end-to-end engineering research that integrates systems technologies with real users and applications.

DataNumerous

inexpensive,

closely‐

spacedradars

CASA’s Radar Network Innovation Concept

Weatherhazards

gap

Multipleend users

Tasking

Innovation = “fresh thinking that adds value to practice & use”

Presenter

Presentation Notes

Dave CASA’s ambition is to revolutionize our ability to observe, … hazardous weather events. Doppler weather radars are the cornerstone of weather warning and response today. Current radars are physically large, high power systems capable to detecting tiny raindrops hundreds of km away from the antennas. But owing to the large separation between the radars in the national network, and owing to the curvature of the earth in between, the radar beams can’t actually see the weather in the lowest part of the atmosphere as shown in the top left of this figure. That’s a problem because the lower atmosphere is where storms originate and its where they actually impact us. This problem fundamentally limits the accuracy of today’s forecasts and warnings of hazardous weather events like tornadoes and flash floods and hurricanes after they’ve made landfall. CASA’s innovation is shown in the lower right. Our idea is to supplement, or perhaps replace, today’s network of 150 large long range radars with networks comprised of thousands of small, light, short range radars installed on cell towers and rooftops as a way of defeating the earth curvature problem. If we can do this cost-effectively, it would revolutionize the observation and forecasting of hazardous weather events. Creating a software architecture to manage the resources in the system is a very significant challenge. There’s the technical challenge of moving all the data around, and then there’s also the challenge of figuring out what data to give to which end-users since forecasters, emergency managers, the media, and the public are all decision makers when it comes to responding to weather hazards.

76

VisionEMASS - (Electro-Magnetic, Acoustic Sensor System)

Network of co-located radar (EM sensors) and infrasound arrays (Paroscientific absolute pressure sensors)

Synergistic technologies - one technology overcomes the limitations of the other

Radar is good for weather diagnosis……but is limited by range, sample rate, attenuation, clutter, interference, line-of-sight

Infrasound (today) is not good for weather diagnosis……but provides continuous, long-range, omni-directional surveillance

Value - Improved weather hazard warning and response through collaborative networks of synergistic remote sensing technologies

GoalProof-of-value for the problem of tornado warning and response

Co-locate infrasound arrays with the CASA IP1 radarsInfrasound arrays geolocate infrasound detectionsFeed those detections that fall inside the IP1 testbedinto CASA’s radar control systemRadars scan the source of infrasoundAtmospheric scientists use radar and infrasound signals to identify signatures of hazardous weather and its precursorsMature the concept to the point where infrasonic detections are being fed into the operational warning and response system (AWIPS, WeatherScope) for end-user evaluation and training

At the same time identify an infrasound network design that is cost effective for large-scale adoption and deployment

Value - increased tornado lead timesA long-standing and very important NWS goal

Co-located deployment of infrasonic arrays in CASA’s

IP1 testbed

radar network in southwestern Oklahoma

Timeline

1/10 1/11 1/12

UMASS

Prototype array

deployment

Project

Launched

1/10.

Testing:Wind FilterBeamformingOperational Bandwidth

IP1 DeploymentIP1 Site Logistics

Design Review

Data flowing to

Atmospheric

Scientists

NSF Proposal

Automated

detections

Infrasound

in MC&C

Displayed in

AWIPS

Operational

Users

Research

Publications


Quartz Seismic InstrumentationQuartz Seismic InstrumentationDigital force sensors have been applied to measure a variety of physical parameters including pressure, temperature, load, angular rate, weight, and acceleration. Resonant quartz crystals, that change their frequency of oscillation with applied load, have many sensing advantages over analog devices. These advantages include the ease of measurements in the time domain, remarkable resolution, high accuracy, low power consumption, excellent long-term stability and insensitivity to environmental errors. Thus quartz sensor technology may also meet some needs of the seismic community.

Digital force sensors have been applied to measure a variety of physical parameters including pressure, temperature, load, angular rate, weight, and acceleration. Resonant quartz crystals, that change their frequency of oscillation with applied load, have many sensing advantages over analog devices. These advantages include the ease of measurements in the time domain, remarkable resolution, high accuracy, low power consumption, excellent long-term stability and insensitivity to environmental errors. Thus quartz sensor technology may also meet some needs of the seismic community.


Resonant Quartz Crystal AccelerometersResonant Quartz Crystal Accelerometers

An intrinsically digital, triaxial accelerometer with a full scale of ±3 g’s was developed with a dynamic range of 176 dB (to 5 nano-g’s) using nano-counting techniques. The dynamic range is at least an order of magnitude higher than existing products.

Advantages include small size, low power, shock protection, and a suitable temperature range for oceanographic and seismic vault installations.

Applications include Earthquake Monitoring, Directional Drilling, Gravity Surveys, and Monitoring of Carbon Sequestration.

An intrinsically digital, triaxial accelerometer with a full scale of ±3 g’s was developed with a dynamic range of 176 dB (to 5 nano-g’s) using nano-counting techniques. The dynamic range is at least an order of magnitude higher than existing products.Advantages include small size, low power, shock protection, and a suitable temperature range for oceanographic and seismic vault installations.Applications include Earthquake Monitoring, Directional Drilling, Gravity Surveys, and Monitoring of Carbon Sequestration.


Quartz Triaxial Accelerometer (Circa 2008)

US Patent 6,826,960, Schaad and Paros, “Triaxial Acceleration Sensor”


Quartz Triaxial Accelerometer

Acceleration Sensing Resonators

Temperature Sensing Resonators

Quad Oscillator3 Acceleration +1 Temperature

Counter & DigitalProcessing Electronics

Inertial Mass TriaxialMechanism


LunarLunar--Solar Gravitational TidesSolar Gravitational Tides Measured with Quartz Seismic SensorMeasured with Quartz Seismic Sensor


Earthquake Nano-Resolution with3-g Full-scale Quartz Seismic Sensor

Honshu (Japan) Earthquake (13 June 2008)Measured in Seattle WA (USA) with IIR nano-counting

Triax IIR Alpha=0.0005 Honshu M=7.2 (6/13/08 23:43:46 UTC) 16:40-17:40 PDT

0 1 2 3 4 5 6 7 8 9 10

Minutes

1000

ng/

div


Paroscientific, Inc.Paroscientific, Inc.Quartz Sensors, Inc.Quartz Sensors, Inc.

4500 148th Ave. N.E.4500 148th Ave. N.E.

Redmond, WA 98052Redmond, WA 98052

www.paroscientific.comwww.paroscientific.com

07-30-10

quartz resonator technology - paroscientific, inc. - continued/quartz... · 2017-02-28 ·...

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