Radioactivity measurements using embedded processing

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Radioactivity measurements using embedded processing

Aran Mol, INCAS3

July 6th 2014 TIPP2014 Amsterdam

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What is INCAS³?• A private research institute

• Driven by industry and social demands

• Full development cycle from needs analyses to product

• Strong international academic and industrial network


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Example projectsAgroBot

RoboShip

SinBot

Other examples:

SPRINT – Balance training for elderly people

MoreWise – Mapping underground oil reservoirs

Panic detection – Automatic classification of sound events

ENSA/DROPS – Monitoring (natural) radioactivityJuly 6th 2014 TIPP2014 Amsterdam

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Radiation detection

• Focus on low levels of (natural) radioactivity• Many applications

• Geophysics• Oil & Gas• Medical• Environmental• Security• …

April 2nd 2014 TIPP2014 Amsterdam

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Challenge = to “sensorize”

• Move “acquisition chain” to embedded solution

• In our case:• Embed detector drift feedback algorithms• Embed spectral processing algorithms• Embed data storage• Embed data visualization


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System philosophy

• Early digitization• Local processing, self diagnostics, calibration

Environment Transducer Embedded processing

InformationADC

Control


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Detector system

• Complex sensor• Modular approach

24Gb/s

FPGA

+V

-V

ADC

±1.0 V500MHz spectra activity concentrations

NaI


http://www.google.nl/url?sa=i&rct=j&q=ARM+CPU&source=images&cd=&cad=rja&docid=Bs9YGLt8MJrUMM&tbnid=ve07OMKfc382NM:&ved=0CAUQjRw&url=http://www.techspot.com/news/44850-arm-signs-29-licensing-deals-ships-19-billion-chips-in-q2.html&ei=X_V4UdL8OMbHswbsyIDQDQ&bvm=bv.45645796,d.Yms&psig=AFQjCNF0qVJw2W2FxtgfwqCduiPn2hg97Q&ust=1366968024298118


















8July 6th 2014 TIPP2014 Amsterdam

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System overview• Modules in stack• 3 main boards

• Fast ADC board• FPGA board• ARM board

• 1 for additional functionality

• Additional DACs & ADCs• Connectivity• GPS


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ADC board• Signal conditioning

• Single-ended• Balanced• Amplification

• Digitization• 2 GHz; 12 bit; single channel

+V

-V

ADC

Analog signalRegister settings

Digital data


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FPGA board• Event detection• Event descriptor extraction

• Energy• Time of detection• ...

• Performance parameters• Signal stability• Baseline tracking• Noise tracking• Pile-up rejection

FPGA

Spectra or raw dataRegister readoutADC settingsClock signalsPower

ADC dataparameters


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FPGA board - signal analysis

• Parameters set at runtime by user

• Dead time: 1.14 µs (maximum)

Time (a.u.)

Ampl

itude

(a.u

.)signalMWDMA

FIR - MWD FIR - MA

baseline amplitude

histogram


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ARM board• Ethernet connection• Temperature

stabilization of spectrum• Full spectrum analysis• C++ code on Linux

buildroot• Interface server

Measured spectra & raw dataHV readoutRegister readoutUser settings

ActivitiesAnalyzed spectraRaw dataParameters



http://www.google.nl/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=c9zCkk6fpddbBM&tbnid=3bExVhHuRDu4MM:&ved=0CAUQjRw&url=http://www.logicsupply.com/products/bb_bblk_000&ei=NmV2UruZNs3Hsgbmu4D4BQ&bvm=bv.55819444,d.Yms&psig=AFQjCNHCqo9b4q73RN9Up4Pwxe3Lgb2vMA&ust=1383577032811967

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• Calibrated reference spectra for U, K, Th, (+ Rn)• Weights to equalize the errors• Yields activity concentrations and accuracy of

estimation

ARM board - FSA


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Full-Spectrum-Analysis

𝐀=(𝐲𝐖 )∙(𝐗𝐖 )T ∙ ((𝐗T𝐖 ) ∙(𝐗𝐖 ))− 1

𝐖=1

√𝐗𝐀

𝐮=1

√𝐖𝐗T𝐖𝐗

Activity

Uncertaint

y

Weight factors

𝐖𝐲=𝐖𝐀𝐗


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Calibration procedure• Volume source: semi-

infinite brick castle• MCNPX simulations used to

determine detector response

• With detector response known, standard spectra can be calculated for any isotope and geometry


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Precision

• Energy resolution of detector: 7.0 % at 662 keV

• Very accurate activity estimations

• Very small nonlinear term


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Interface

• Web server • Easily accessible• Easily changed

• Tabs:• Live view• Settings• Data storage• System lineage


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• Dynamic Rain Observation & Parametrization System

• High-school collaboration project

• Study correlation between weather and radon activity

DROPS project222Rn

222Rn

222Rn


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DROPS results

• Continuous dataset from 22 July to 22 October


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Ongoing work...• Continued development of detector electronics &

scintillator signal processing• Testing & certification

• Field testing Canada• Temperature and mechanical stability testing

• Advanced real time analysis & control• Pile up correction

• Pulse shape discrimination• Neutron detection

• Improve fitting procedure


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Applications

• Environmental monitoring• Pilot: Uranium mining Canada

• Precision farming• Soil content in sugar beet harvesting

• Nuclear reactor monitoring• First tests expected this year


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Thank you

INCAS3 is sponsored by:


Documents

Radioactivity measurements using embedded processing