International Workshop on the Use of Robotic Technologies
at Nuclear Facilities

R&D on Robots for the Decommissioningof Fukushima Daiichi NPS
February 3, 2016
Kiyoshi OIKAWA
International Research Institute for Nuclear Decommissioning (IRID)

Introduction
IRID is the Technology Research Association to develop technologies required for thedecommissioning of the Fukushima Daiichi NPS
Organization
R&D Management

Relationship Diagram• R&D Management• R&D Strategy Planning• Administration

METI

Strategy Planning
R&D Planning & management

R&D Implementation• Membership:
National R&D Agencies(2)/Manufacturers(4) / Electric Utilities(12)•Over 700 researchers participate in IRID andengage in the R&D projects at their facilities

NDFSpecialization& Cooperation

Scope of businessNuclear decommissioning technology R&D•Fuel Removal from Spent Fuel Pool
•Preparation of Fuel Debris Retrieval•Treatment and Disposal of Radioactive Waste

TEPCO

Decommissioning Policy“Mid-and-long Term Roadmap”

IRID

R&D Management
R&D Implementation

Fukushima Daiichi NPS
D&D Engineering
METI: Ministry of Economy, Trade and Industry
NDF: Nuclear Damage Compensation andDecommissioning Facilitation Corporation

Promotion of cooperation on nuclear decommissioning
with international and domestic organizations
Human resource development
For more information >> http://www.irid.or.jp/en2©International Research Institute for Nuclear Decommissioning

Fuel debris retrieval procedure
Robot technology is utilized for decontamination in the reactor building, investigation of waterleakage from the PCV, investigation of the PCV interior, etc., according to the Mid-and-Long-Term
Roadmap indicating the decommissioning procedure of Fukushima Daiichi.
Current

Technology R&D

Fuel Debris Retrieval from 2021

Removal of fuel from
Spent fuel pool
Submersion
methodPartial submersion method
Top EntryDecontaminationof work area andwalkway

Side Entry

Investigation of RPV interior
・Location and configuration offuel debris
・Damage of structural material

Investigation of PCV interior
・Location and configuration offuel debris
・Damage of Pedestal and PCV
Fuel debris

Investigation andstop of waterleakage from PCV

3©International Research Institute for Nuclear Decommissioning

Development of technology for remotely operated
decontamination in reactor buildings
Robots capable of accessing various places such as low places like floors, high places where pipes
and trays are located and narrow places, and decontaminating various types of contaminants suchas loose contaminants like dusts and fixed contaminants that penetrate into and fixate on concrete .
For High Places
Suction/High pressure
Dry ice blast
water injection70%

For Low Places

Suction/blast

Expand20%

Air doseHigh pressure
water injection

Ground floor of Reactor Building
For Upper Floors
Compressor Unit

100m

40m

Decontamination Unit
20m

Work Unit

Dry ice blast

Each unit is lifted up to the upper floor with the Lifter in continuity

4©International Research Institute for Nuclear Decommissioning

Development of technology to identify leakage points in the PCV
Equipment to investigate water leakage from the PCV etc., which is designed to be adaptable tovarious environments , including elevated locations, high radiation dose areas, narrow spaces, andunderwater areas④ Wall penetration survey
equipment of torus room

① Upper part of S/C survey equipment
3.8m

Water leakage

SurveyRunner0.8m

Details of portion to beinvestigated of lower PCV

Swimming robot

Floor traveling robot

Tracerinjection
S/C
CameraVacuumbreak line

Tracer①Reflection②② Exterior surface survey
equipment for Vent PipeTo search a water leakage
on the junction of the Vent
pipe and the PCV

ReflectionSonar③④③ Exterior surface survey
equipment for lower part of S/CTo search a hole (>30mm) onthe S/C surface under water

VT-ROV

SC-ROV5©International Research Institute for Nuclear Decommissioning

Development of technology for investigation of the PCV interior
Robots capable of going through a 100 mm-diameter guide pipe and moving around a wide area inthe PCV and having a radiation resistance strong enough to capture images and measuretemperatures, radiation doses, under high radiation doses, in dark or vapor atmospheres
Shape-changing crawler (Unit 1) Camera& Light

Moving within pipes
Dosimeter
Shape changing Moving along
flat surfaces

Thermometer Small size crawler (Unit 2)
CameraCamera& LightCrawler

CameraRise Up mechanism
CrawlerComing in the inside of
the pedestal via CRD rail

【Unit 1】
X-100B
penetration(φ115mm)【Unit 2】
X-6
penetration
CRD rail6©International Research Institute for Nuclear Decommissioning

Utilization of 3D data on the reactor building interior(Decontamination)
3D data of the reactor building captured through laser scanning is utilized to study methods toapproach high and narrow places to be decontaminated and to design the mockup facility
simulating the structural condition and arrangement of each Unit.
3D Model on CAD①②③

Traveling route from outside of Unit 1
to the target area of decontamination

Integration test at
mock-up facilities

AAB

3D scanned data of Unit 1①Narrowest place
Pipes

1670mmOverhead rail・Vacuum pump・HEPA filter
・Collect tank・Water pressure Fence
・Air compressor
・High pressure water
780mm
・Control panel②Dogleg passage
in narrow placeWinding reelHigh pressure
water injection
platform truck

B
Designing Mock up facility③Target area of decontamination

AB

Slope to step over theauxiliary pipes and wiring

7©International Research Institute for Nuclear Decommissioning

Evaluation of robot performance (Decontamination)
Robot that meets specified requirements not only for decontamination performance but also forremote control , linkage with other system components and safety performance
Rear
CameraLine laser

Side (right-hand)High pressure water
Camerainjection headCamera
Linelaser

Relief mechanismof crawler andoutrigger
Outrigger
CrawlerDecontamination
performance

Air blow

LightRange
finderWater
injection
nozzleWater
suction port

TargetWork area 3mSv/h, Travel pass 5mSv/h

Cameramax 6105 mm

Evaluation Item

FlipperHigh pressure water
injection headFront• to remove 80% contaminated material• to collect injected water on the floor< 1mm water level @ flat floor< 10mm water level @ hollow place

Decontamination work

• to access to 8m high place and operate the decontamination work

Remote control
performance

Travelling

Safetyperformance• to avoid falling down during the decontamination work @ 8m high place• to make emergency stop on abnormal condition• to draw the machine back using traction tool on emergency stop state• to move the machine dragging a long harness behind throughthe narrow passage in the mock up facilities

8©International Research Institute for Nuclear DecommissioningReliability improvement through testing(Investigation of the PCV interior)

To develop a highly reliable robot, it is vital to repeatedly examine robots under environments thatsimulates the PCV.
Improved points at postulated severe situation in the PCV
 Dark and foggy circumstance• LED light with condenser and distant from the camera• Image processing Difficulty in grasping site situation though remote control operation• Two cameras give a good visual field, overlooking picture aroundof the robot and close up picture in front of the robot• Rear camera gives wide area view with Pan/Tilt mechanism
 Roll over
• Self-righting using the rise up mechanism
 Out of control• Cable delivery system has the cable cutoff mechanism
Points of improvement
Old model

Visibility test in water vapor
Transparency 100%
Transparency 20%

Image processing

New model
Rear Camera withPan/Tilt mechanism
LED Light with
Condenser

Front Camera withTilt mechanism

Rise Up mechanism

9©International Research Institute for Nuclear Decommissioning

Development of a step-by-step investigation(Investigation of the PCV interior)

Since the situation inside the PCV is not much known, we have divided the investigation of the fueldebris in the PCV into several steps in order to reflect results from the current investigation step tothe next step.
Steps for the PCV interior investigation
Camera on foldableand expandable pole
① CRD rail condition (2014)② Platform condition (on-going)

Vent③ CRD bottom area condition (from FY2016)

Pan/Tilt
Camera&Light④ Pedestal basement condition (from FY2017)

Deposit removing robot

Refine the Procedure and method of the Fuel Debris Retrieval③ CRD bottom area
① CRD rail
PCV penetration(X-6)

Water injection
Investigation robot② Platform④ Pedestalbasement
CRD: Control Rod Drive10©International Research Institute for Nuclear Decommissioning

Technology for preventing radioactive material diffusion(Investigation of the PCV interior)

Before putting the robot into the PCV, we must build a boundary to avoid an opening of the PCVfrom diffusing radioactive materials .
Radioactive material diffusion preventing device (Chamber)
Small size crawler (Unit 2)

Shape-changing crawler (Unit 1)

X6
Penetration
Guide pipe

Robotinside

End ofguide pipe

Robot
Cable delivery
drum

Robot

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©International Research Institute for Nuclear Decommissioning

Radioactive resistant performance
The requirement for radioactive resistance of each robot is specified, according to a dose rate of aplace where the robot works.
General purpose
Field robot “Quince”

Camera

Dose rate map in the Unit 1
1.2

1.9

Sensors formeasurement

Laser RangeFinderComponent parts

Dose tolerance

Laser range finder

124Gy(Sv)

CCD camera

169Gy(Sv)

CPU module, Battery,
Motor driver, RadioTx/Rx, LAN HUB, etc…

> 200Gy(Sv)Management guideline• Unmanned heavy machine
20Sv total dose
• Portable field robot
30Sv total dose

4.5
2.0

3.0
2.5

4.5
3.5

7.0

8.0 3.0
22.0

20 11.4Upper
1.５100
Upper
9.050
1200

3.5

Upper

1700
MAX 23
4.0X493.5 3.5
MAX800
4.5
5.0
3.5
Floor
4.0
2100
6.0100
230
5.0
5.0
6.0
4.5 7.0 20
Floor2200 4700
6.5 7.0 7.5 15 40 95
6.5 7.0 8.0
120 54 247 300 220 1100 1280
90290 800 1820
5.01526 138 600 290
60
48 127
3.5

CPU module, Battery, Motor driver
Dose tolerance test (Cobalt 60)

Investigation of Inside PCV(measured 2012 ~ 2013)

7.0

X40B

Requirements
100Gy/h
1000Gy total dose

Fuel debris retrieval
Requirements
10kGy/h2MGy total dose

< 3mSv/h 3mSv/h ~ 10mSv/h 10mSv/h~ 20mSv/h
20mSv/h~ 50mSv/h > 50mSv/h• “Guideline on Rad-Hardness Estimation and Managementfor Robotics, Unmanned Construction Machine andothers” 2011.4.27 (Original document is Japanese)• "Radiation resistance and decontamination of robots inthe field of atomic energy"IEEE Telerobotics Summer School 2013 , Shinji
Kawatsuma, Japan Atomic Energy Agency, Japan

Decontamination
Requirements
3Sv/h～20Sv/h
1000Sv ～2000Sv total dose

Investigation of leak of PCV
Requirements
4Sv/h～10Sv/h
200Sv total dose

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©International Research Institute for Nuclear Decommissioning

Study of fuel debris retrieval method
We will study multiple method for fuel debris retrieval to meet different condition of damaged PCVand scattering fuel debris at each unit
Submersion method

Partial submersion method (In-air work)

Most favorable approach forminimizing the radioactive
exposure of workers

Development of technology which prevents scattering radioactive materials
from PCV is needed to remove PCV contents in-air work

Top entry

Side entry

PCV head

WireWorkplatform

When fuel debris spreads overpedestal outskirts, the side
entry method is to be selected

RPV head
Steam dryer
Steamseparator

Sealing a PCV head (1:4scale) with Radioactive
material diffusion
preventing film

Hydraulicmanipulator

Access railHydraulicmanipulator

Fuel debris

13©International Research Institute for Nuclear Decommissioning

Thank you for your attention