November 2019 No.85

IDI

Japanese Infrastructure Newsletter

QUARTERLY
InfrastructureDevelopment

Institute—JAPANKUMONOS is a total station which has a built-in crack scale and 3D database management system.

CONTENTS
Cracking Inspection System KUMONOS

2

3D Laser Scanning

4

Infrastructure Development Institute – Japan (IDI)
Plaza Edogawa-bashi 3F. 1-23-6,Sekiguchi, Bunkyo-ku, Tokyo, 112-0014, JAPAN
Tel: +81-3-5227-4107 Fax: +81-3-5227-4109 E-Mail: idi17@idi.or.jp Website: http://www.idi.or.jp/english/00index.htm

Cracking Inspection System KUMONOS

1. Introduction
In recent years there have been lots ofespeciallyserious accidents caused by deterioration ofconcrete structures.

necessaryfor

maintenanceofinfrastructure not only in Japan but also inmany countries. Therefore the demand forIntheconventional

methods

ofcrack

preventive maintenance and management ofinspection a dedicated ruler, called crack scale

those structures has been steadily growing andis used to measure widths. Shapes and lengths

became urgent nowadays.

of the cracks are recorded by sketching. Suchmethods require close-up visual inspection, soOur company has been contributing tothat scaffolding or boom-lift at out-of-reachmaintenance and management by performing

places become a necessity. This increases laborvariouscosts and significantly decreases efficiency.

types

ofmeasurements

ofthosestructures.

We

promotetechnology

development

andintroduce

thelatesttechnologies

to"measuresafelyandaccurately."

Moreover, workers safety is jeopardized.
Since the conventional inspection methods
rely

heavilyonhuman

factorssuchasprofessional skills and diligence of a particular
Among

all

inspection

andmonitoring

methods that are used, crack inspection isworker, it tends to be difficult to record shape,length and width of a crack accurately.

Remote Concrete Measurement System “KUMONOS”
2. Overview of the Inspection Method
We developed “Crack Inspection System

Then, the shape, length and width of the crack“KUMONOS” that makes possible to safely

quantitatively.

measure cracks from a long distance away

three-dimensional coordinates of measured

without using neither scaffoldings nor thecracks are saved, consecutive measurements atboom-lifts; and allows to record crack’ shapes

the same locations allow monitoring andand evaluate their width with an order ofquantifying

0.4mm from distances as far as 100m away.

expansion.

November 2019 No.85

can be converted into the data and recorded

theirFurthermore,

continuous

growthsinceand2

As crack data obtained by “Crack Inspection
System KUMONOS” can be expressed in three
dimensions, it can be used in combination with
3D data obtained by 3D laser scanner which isalso one of our key technologies. Based on thesedata,

maintenanceinfrastructure

andobjects

canmanagement
beofconducted
Figure.3

thoroughly and efficiently.

-Measure cracks using KUMONOS (Figure 4)
Method Comparison
Experiment to compare conventional methodwith KUMONOS
Ⅰ.Conditions
Subject: 3 people with 2-day technical training
Object: 5 simulated cracks drawn on a sheet ofpaper (Figure 1)
Conditions: distance – 50 meters, 1
measurement←420mm→Figure.4←297mm→③Prepare resulting drawing in AutoCAD④Over impose resulting drawings from bothmethods and analyze the differences.
Ⅲ. Results
Comparison Accuracy (Position and Shape)

Ⅱ. Methodology

Figure.1

KUMONOS

Conventional Method

1mm ~ 3mm 28mm ~ 46mm

①Attach sheet with cracks to the wall as inFigure 2.

*Accuracy: The difference between the figure
and the cracks to be measured
The Result of Measuring the Widths (OnlyUsing KUMONOS)
ResultCrack
No.

ActualWidth(mm)10.20

0.22 0.22 0.18

0.21±0.02

20.40

0.42 0.36 0.44

0.41

±0.04

30.09

0.10 0.14 0.14

0.13±0.05

Figure.2

40.20

0.22 0.18 0.22

0.21

±0.02

②Monitor position and shapes of cracks in two
following ways:-Observe the cracks through a pair ofbinoculars and sketch them on the paper as inFigure 350.30

0.32 0.29 0.32

0.31±0.02

November 2019 No.85

ABC

Average Accuracy*Accuracy: The difference between the figure
and the cracks to be measured
Obviously, KUMONOS is way more accurate
than the conventional method
Width accuracy is within 0.05 mm even whenmeasured from 50m away.
3

3D Laser Scanning
4. 3D Laser Scanning Technology

Aiming at early recovery of Kumamoto Castle,

3D laser scanner is an instrument thatthe 3D data was used to examine the structuralacquires 3D positional coordinates of the target

conditions to implement restoration planning.

object by laser beams emitted from theinstrument. Just by pressing a button on theWe became number one in Asia for 3D laser

instrument, it is possible to acquire positionalscanner sales in three consecutive years. We

coordinates of all surrounding as a point cloud

have been accumulating achievements anddata

pointsexperiences in various fields since 20 years ago

combined in one entity) in a short time.

when we started development of the technology.

(largenumberofmeasures

KUMONOS Corporation has introduced 3D
laser scanners into the market way ahead ofother manufacturers.
In recent years, this technology has been usedin the following sites:■Plants and Ships
3D laser scanner can measure shapes as theyare,makingittheidealsolution

Figure.5 Example of scanning inside of a plantfor

measurements of and in vehicles and complex
facilities such as ships, airplanes, inside
manufacturing or chemical plants and etc.
Modeling of piping and instrumentation basedon point cloud data makes it possible to handle
it as CAD data thus simplifying design anddrafting, monitoring and management. Itenables

easy

checksoninterferencebyFigure.6 Point cloud data

complicated piping, securing distances between
welds and etc. 3D scanned data is also used toformulate plans for expansion of facilities andlayout changes.
■Historic Buildings and Cultural Properties
At the time of Kumamoto earthquake in 2016,
we performed measurements of real-time

Figure.7 Modeling data from point cloud data

situation using a 3D laser scanning technology.
November 2019 No.85

4

5. Recent Activities

technology and wall diagnostic system toWe can offer expertise with wide variety of 3D

stadium maintenance as well as utilizing 3D

laser scanners. Both fixed types and mobile

measurement data for VR technology in thetypes are available. Fixed types are used forfuture.

measurement in the fixed state on tripods, andmobile types are used for measurement whilemoving. In particular, we are the only company
in Japan that can use backpack-type 3D laser
scanners

with

which

youcanperformmeasurements by carrying the scanner on yourback. Such backpack-type scanner was used inFigure.8 Point Cloud data of Sports Stadium

Nepal for measurements aimed at recovery andrestoration of urban and cultural heritage

Contact: Ayuna Kitaura, International Businessareas heavily damaged by the earthquake ofDivision, KUMONOS Corporation

2015.

E-mail: a.kitaura@kankou.co.jp

Furthermore, we have been expanding ourPhone: +81 72-730-0009

business scope in the sports field. We are alsoplanning of introducing 3D laser scanning

November 2019 No.85

5

About IDI and IDI-quarterly
Infrastructure Development Institute (IDI)-Japan is a general incorporated
association operating under the guidance of Ministry of Land, Infrastructure,
Transport and Tourism of Japanese Government.
IDI provides consulting services for mobilizing International Assistance todeveloping countries, promoting international exchange of information and humanresources, and supporting globalization of project implementation systems targeting
both developed and developing countries in the field of infrastructure.
IDI has been publishing the free quarterly journal “IDI Quarterly” since1996 for the
purpose of introducing information relating to public works and construction
technologies developed in Japan to foreign countries. We have distributed thejournal to administration officials in more than 90 countries around the world bye-mail.
It is highly appreciated if you would send us your opinions, impressions etc on thearticles.
We are also welcoming your specific requests on articles to pickup for the following
Quarterly issues.

November 2019 No.85

6