Real Time Control for
KAGRA
covered by EPICS
May 17, 2017
Spring 2017 EPICS Collaboration Meeting

Osamu Miyakawa (ICRR, UTokyo)
on behalf of
KAGRA collaboration
JGW-G1706727

EPICS meeting at KURRI, 2017/5/16, Osamu Miyakawa

1Gravitational waves detected by LIGO

Credit: LIGO Scientific Collaboration

2

Network of GW detectors

KAGRA

GEO-HF

3km, underground

LIGO-India in proposal

600m

LIGO Hanford

Advanced-Virgo
4km
LIGO Livingston

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3km

LIGO-Australia in proposal

34km

KamiokaTokyo• KAGRA is located in Kamioka mine underground- 220km away from Tokyo- 360m altitude- Big laboratory area
XMASS
(dark matter)
XMASS
CLIO(GW)

CLIO

KAMLAND(neutrino)

KamlandSuprer KamiokandeSuper
Kamiokande(neutrino)

Office/Control room
KAGRA
KAGRA
(GW)
KAGRA
entrance

JGW-G1706727

EPICS meeting at KURRI, 2017/5/16, Osamu Miyakawa

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KAGRA Project• Host: ICRR Utokyo, Co-host: KEK, NAOJ
• 300+ collaborators from 90+ institutes• Constructed in Kamioka mine
• Underground and cryogenic

JGW-G1706727

EPICS meeting at KURRI, 2017/5/16, Osamu Miyakawa

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Detection of gravitational wave using
laser interferometer
GWs move mirrors differentially.
We measure the distance between
mirrors using fringe of light.
Expected length change by GW :~1x10-19m

MirrorMirrorBeam Splitter

Lens

FringeScreenLaser
JGW-G1706727

EPICS meeting at KURRI, 2017/5/16, Osamu Miyakawa

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How to get More sensitivity with control?

Needs
Control to keep dark
at detection port

Brightport
Dark
port

JGW-G1706727

feedback

EPICS meeting at KURRI, 2017/5/16, Osamu Miyakawa

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Development of optical configurations
Michelson interferometer (MI)Fabry-Perot MI (FPMI)
Control

Keep dark condition at
detection port toreduce shot noiseLonger light path using
Fabry-Perot cavities

Control
ControlPower recycling (PRFPMI)

Dual recycling (DRFPMI)

Higher laser powerby a power
recycling mirror atlaser port

Control

Control

Control

Control

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CLIO

Control

TAMA, LIGO , VIRGO

Control

Enhance the GW signals bya signal recycling mirror atthe dark port
Control

Control

Control
Control

KAGRA,aLIGO, aVIRGO8

Concept of digital system
Real time control

IFOSensors

Real time PC

16kHz
RTcontrolloopwhitening
AAADC

LSC/ASCfiltering

Monitor/Data acquisition

PC• Data acquisition(DAQ)• Slow control by using EPICS• Flexible human interface

Real time dataswitch, gain...

PCControl signal

Data access without
breaking control

dewhitening

Fast monitor

Slow control: EPICS

16Hz

AIDAC

• IFO is a multiple DOF plant
which has many sensors andactuators• Produces control signal using
computers

Actuators

NetworkPC

Data storage

16kHz
PC

16kHz full data
16Hz EPICS data
1 second data
1 minute data

KAGRA control network design
Computer center

Remote Control room

Metal cable
Fiber cable

GPS antenna

OutsideTimingmaster

Client workstations

Front roomMine

3km Y arm cavity

Data storage

Laser

3km X arm Cavity

SeversCircuit

Generalnetwork

TCP/IP: EPICS, NFS, network bootDAQ
network GW data: huge amount, low latency

CircuitLong RFM
RT control signal: very low latency
network
Short RFM RT control signal:
networkvery low latency

X end

Timingnetwork

Real-time PCs

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Center room

3km

EPICS meeting at KURRI, 2017/5/16, Osamu Miyakawa

Y end10Control system

Remote control room

DC power supplies
for remoteelectronics

Computer room
in KAGRA mine
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①

DAQ network③
concentrator
distributor

frame writer
frame writersendersender

Real time PCs rack

network switch

timingtiming②

network

network
circuits
RT PC
RT PC
ADC/DAC

RT PC.
.

200TB
storage.

④

Mine Outside

20TB storage
20TB storageUPS
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~7km

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System layer map
Built on RTPCs

Epics IOC

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Epics IOC

345

EPICS meeting at KURRI, 2017/5/16, Osamu Miyakawa

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Source codes by GUI:
Libraries for Real time model on Matlab, Simulink
Sensors
6DOF input
signalsInput Feedback
Matrix filters

Actuators
OutputMatrix

6DOF output
signals

Globalcontrols
Whitening/dew
hitening
Switches

JGW-G1706727

EPICS meeting at KURRI, 2017/5/16, Osamu Miyakawa

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Generated C source of Real Time code from GUI
Actual control signals（filter bank, matrix, trigger, linearization etc.）will be generated automaticallywhen building real time modules.
.
.
//Start of subsystem LSC **************************************************// FILTER MODULE
lsc_pox = filterModuleD(dsp_ptr,dspCoeff,LSC_POX,dWord[0][0],0);// FILTER MODULE
lsc_poxfb = filterModuleD(dsp_ptr,dspCoeff,LSC_POXFB,dWord[0][1],0);.
.
for(ii=0;ii<1;ii++){
lsc_nxmtrx[1][ii] =pLocalEpics->ctr.LSC_NXMTRX[ii][0] * lsc_trx + pLocalEpics->ctr.LSC_NXMTRX[ii][1] * lsc_poxdc;}// Relational Operator
lsc_operator = ((pLocalEpics->ctr.LSC_XTHRESH) <= (lsc_trx));// DIVIDE
if(lsc_nxmtrx[1][0] != 0.0){
lsc_divide = lsc_pox / lsc_nxmtrx[1][0];}else{ Running as
lsc_divide = 0.0;
} kernel modulesof LinuxJGW-G1706727

EPICS meeting at KURRI, 2017/5/16, Osamu Miyakawa

Produced channels• Test Point channel: Anchor point of data stream, not tobreak control loop. Fast real time data (16kHz), limited
number to access up to 24/RTPC at a time. ~10000ch.
• DAQ channel: selected channels from Test Point. To be
stored into disks. Decimated from 16Hz to 16kHz.
Available to see the past data. ~1000ch.
• Epics channel: Automatically produced when RT codebuilt, named with similar name as Test Point. Slow(16Hz), stored all the data, accessible to the past data.
~100000ch.
– No need to write/edit EPICS channel database manually.
JGW-G1706727

EPICS meeting at KURRI, 2017/5/16, Osamu Miyakawa

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JGW-G1706727

EPICS meeting at KURRI, 2017/5/16, Osamu Miyakawa

Output to suspensions

A/D

Feedback filters

mixer

Demodulated signal
from PD

MEDM --Length sensing and control system

D/A17

EPICS covers realtime signals
Software for real time access:• Dataviewer: osciloscope,• DTT: FFT analyzer• Foton: digital filter composer• Foton: GUI digital filtercomposer

Some MEDM screens are produced
automatically when built.
• Signal excitation• 10 filter banks• 3 monitor point IN1/IN2/OUT

JGW-G1706727

EPICS meeting at KURRI, 2017/5/16, Osamu Miyakawa

Guardian• Guardian is an application covering on EPICS tomanage states of interferometer.
• Automatic lock acquisition: down -> locked ->operation by looking EPICS channel info.

Review of Scientific Instruments 87, 094502 (2016)19EPICS on Web UI using php-epics
EPICS gateway provides external accesses to channel data from outside
network of the laboratory.
However users need MEDM installation on their local PCs.
The php-epics can call some channel access method. (ca_get, ca_put, etc.)
We developed Web UI for accessing channels using php-epics, but all theadl files needs to be manually converted.

Web UI

Original UI using ADL fileEPICS on Web UI using HTML5 + javascript
Automatic conversion of ADL is done using HTML5 + javascript, but
without channel access.
We need a little more time to merge php and HTML5 + javascript foran automatic conversion with channel access.

Web UI
Original UI using ADL file

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Overall plan

Phase 1
Initial KAGRA

Michelson at room temp.

Michelson with twocryogenic mirrors.

Phase 2

Four cryogenicmirrors.

Phase 3

DRFPMI with fourcryogenic mirrors.
Observation run