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Mineo, Carmelo and Pierce, Stephen Gareth and Nicholson, Pascual Ian
and Cooper, Ian (2014) Robotic path planning for non-destructive testing
of complex shaped surfaces. In: E-Book of Abstracts, 41st Annual
Review of Progress in Quantitative Nondestructive Evaluation
Conference. Center for Nondestructive Evaluation, Boise (USA). ,
This version is available at https://strathprints.strath.ac.uk/54912/
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Robotic Path Planning for Non-Destructive Testing of
Complex Shaped Surfaces
Carmelo Mineo1, a)
, Stephen Gareth Pierce1,
Ben Wright2, Pascual Ian Nicholson2, Ian Cooper2
1University of Strathclyde, Department of Electronic and Electrical Engineering, George Street,
Glasgow, G1 1XW, UK 2TWI Technology Centre (Wales), Harbourside Business Park, Port Talbot, SA13 1SB, UK
Abstract. The requirement to increase inspection speeds for non-destructive testing (NDT) of composite aerospace parts
is common to many manufacturers. The prevalence of complex curved surfaces in the industry provides significant
motivation for the use of 6 axis robots for deployment of NDT probes in these inspections. A new system for robot
deployed ultrasonic inspection of composite aerospace components is presented. The key novelty of the approach is
through the accommodation of flexible robotic trajectory planning, coordinated with the NDT data acquisition. Using a
flexible approach in MATLAB, the authors have developed a high level custom toolbox that utilizes external control of
an industrial 6 axis manipulator to achieve complex path planning and provide synchronization of the employed
ultrasonic phase array inspection system. The developed software maintains a high level approach to the robot
programming, in order to ease the programming complexity for an NDT inspection operator. Crucially the approach
provides a pathway for a conditional programming approach and the capability for multiple robot control (a significant
limitation in many current off-line programming applications). Ultrasonic and experimental data has been collected for
the validation of the inspection technique. The path trajectory generation for a large, curved carbon-fiber-reinforced
polymer (CFRP) aerofoil component has been proven and is presented. The path error relative to a raster-scan tool-path,
suitable for ultrasonic phased array inspection, has been measured to be within 2mm over the 1.6 m2 area of the
component surface.
INTRODUCTION
In civil aerospace manufacturing, the increasing deployment of composite materials demands a high integrity
and traceability of NDT measurements. Modern components increasingly present challenging shapes and geometries
for inspection. Using traditional manual inspection approaches produces a time-consuming bottleneck in industrial
production environments [1] and hence provides the fundamental motivation for increased automation.
The combined use of Modern Computer-Aided Design (CAD) and Computer-Aided Manufacturing (CAM) now
allows large items to be produced easily from one piece of raw material (either through traditional subtractive
approaches, or with more recent additive manufacturing processes [2]). As a result, large components with complex
geometries are becoming very common in modern structures, and the aerospace industry is a typical field, where
wide complex shaped parts are very frequently used. Moreover the use of composite materials, which are
notoriously challenging to inspect [3], is becoming widespread in the construction of new generations of civilian
aircraft. To cope with future demand projections for these operations, it is therefore essential to overcome the
current NDT bottleneck.
A fundamental issue with composites manufacturing compared to conventional light alloy materials lies in the
process variability. Often parts that are designed as identical, will have significant deviations from CAD, and also
-
suffer from inherent but different part to part spring-back out of the mould. This presents a significant challenge for
precision NDT measurement deployment which must be flexible to accommodate these manufacturing issues. For
these reasons, NDT inspection is often performed manually by technicians who typically have to move appropriate
probes over the contour of the sample surfaces. Manual scanning requires trained technicians and results in a very
slow inspection process for large samples. The repeatability of a test can be challenging in structures where complex
setups are necessary to perform the inspection (e.g. orientation of the probe, constant standoff, etc.) [4]. While
manual scanning may remain a valid approach around the edges of a structure, or the edges of holes in a structure,
developing reliable automated solutions has become an industry priority to drive down inspection times. The
fundamental aim of automation within the inspection process is to minimize downtimes due to the higher achievable
speed, and in parallel to carry out 100% inspection coverage of the sample, including all edge areas.
Semi-automated inspection systems have been developed to overcome some of the shortcomings with manual
inspection techniques, using both mobile and fixed robotic platforms. The use of linear manipulators and bridge
designs has for a number of years provided the most stable conditions in terms of positioning accuracy [5, 6]. The use
of these systems to inspect parts with noncomplex shapes (plates, cylinders or cones) is widespread; typically, they
are specific machines which are used to inspect identically shaped and/or sized parts.
More recently, many manufacturers of industrial robots have produced robotic manipulators with excellent
positional accuracy and repeatability. In the spectrum of robot manipulators, some modern robots have suitable
attributes to develop automated NDT systems and cope with the challenging situations sought by the aerospace
industry [7]. They present precise mechanical systems, the possibility to accurately calibrate each joint, and the
ability to export positional data at frequencies up to 500Hz.
Some applications of 6-axis robotic arms in the NDT field have been published during the last few years and
there is a growing interest in using such automation solutions with many manufacturers within the aerospace sector [1, 7-10]. Despite these previous efforts, there remain challenges to be addressed before fully automated NDT
inspection of composite parts becomes commonplace. The key challenges include generation and in-process
modification of the robot tool-path, high speed NDT data collection, integration of surface metrology measurements,
and overall visualization of measurement results in a user friendly fashion. Collaborations driving this vision include
the IntACom project, developed by TWI Technology Centre (Wales) on behalf of their sponsors over a period of 3
years. The project objective has been to achieve a fourfold increase in the throughput of aerospace components [1].
Additionally the UK RCNDE consortium conducts research into integration of metrology with NDT inspection [11, 12]. Both these consortia have identified the requirement for optimal tool path generation over complex curved
surfaces. The current paper describes a novel approach to flexible robotic toolpath generation using a purposely
developed MATLAB based path-planning software platform.
INVESTIGATED PATH PLANNING APPROACHES FOR NDT APPLICATIONS
Traditional Approach
Six-axis robotic arms have traditionally been used in production lines to move the robot end-effector from one
position to a new position for repetitive assembly and welding operations. In this scenario, where the exact trajectory
between two points in the space is not too important, the teach pendant of a robot is used to manually move the end-
effector to the desired position and orientation at each stage of the robot task. Relevant robot configurations are
recorded by the robot controller and a robot program is then written to command the robot to move through the
recorded end-effector postures. More recently, accurate mechanical joints and control units have made industrial
robotic arms flexible and precise enough for finishing tasks in manufacturing operations [13]. Robotic manipulators
are highly complex systems and the trajectory accuracy of a machining tool has a huge impact on the quality and
tolerances of the finished surfaces. As a result, many software environments have been developed by non-robot
manufacturers, academic researchers and also by the robot manufacturers themselves, in order to help technicians
and engineers to program complex robot tasks [14]. The use of such software platforms to program robot movements
is known as Off-Line Programming (OLP). It is based on the 3D virtual representation of the complete robot work
cell, the robot end-effector and the samples to be manipulated or machined. OLP was first achieved within the
-
IntACom
CENIT-Fa
Figure
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s origin from th
ore traditional
ftware applicati
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path generated
fulfilling all th
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e Ultrasonic T
ne receiver; the
Currently, many
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the requiremen
ath, being gener
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r more robotic a
Through-Trans
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any commercial
astSurf allows p
g digital I/O sign
d programming
Systems) [16].
tic representatio
rasound Testing
d effective NDT
integrate the ro
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application rece
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ng software. Th
tion of the orig
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DT inspections
robot manipula
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ection procedur
aves as a serve
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inspection sys
here is still room
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effective NDT i
ftware functions
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ments have a
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he ultrasound
om the robot
in application,
ion. The C++
real-time data
isition module
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type and the
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re for off-line
eneral robotic
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pensive tools,
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developed for
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inspection time
rs monitoring th
illiseconds. Th
on time of each
ly required to pr
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MATLAB bas
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FIGURE 2. Im
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ot language prog
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undamental capa
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robot controller
er to carry out m
and of a more a
sponse to externa
acturing applica
inspection is a c
ese data results
ecessary to reco
NDT data [6]. M
they can inform
be further inte
ation. An exter
l data and perfo
TLAB Based
(herewith refe
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e programming.
c needs of NDT
bots by an extern
puter is used fo
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pplication instea
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e aim is to obta
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tead of commerc
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r position at regu
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lanning Softwa
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btain effective t
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ved. RoboNDT a
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re removes the n
and coordinates
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pecific code is
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of a specific
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ith the precise
hroughout the
equipped with
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ocation at the
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easured NDT
rom scratch to
eneration that
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int supporting
bot controllers
ing positional
T aims to be a
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the new path-
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and the robot
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the integration o
gful data for p
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art to inspect an
oNDT software
anning, evaluatio
n import all the
d to the robot m
ells, complete w
robot models. A
nments Library
3 shows screensh
start-up modul
e can import Sta
ted by the major
anufacturing. T
d robot cell. The
t and insert thei
ates, reported by
path-planning m
ion tool-path for
segment and sin
ity and customiz
ot manipulator i
ntrolling the rob
anages both the
n of metrology.
position error
ensors and the ac
nd the assessm
are has been org
ation and output
he samples and
t manipulator ca
with environme
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are automatica
nshots of each o
FI
dule of the soft
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jority of the exis
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he calibration is
heir positions by
by the robot tea
g module is the c
for each given su
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ization accordin
r is replaced by
robot tool-path,
the robot extern
y. Metrology sen
or monitoring a
e acquisition soft
sment of its posit
organized accor
put module. For
d parts of intere
can be set into
ment parts and
es made to the r
tically transferred
h one of the deve
FIGURE 3. Scre
oftware is respo
ellation Languag
xisting software
module allows th
n is an interactiv
by jogging the
teach pendant, ar
e core of the sof
surface of the p
can. Each path t
ding to the inspe
by a two-way
th, and reception
ernal control and
sensors can easi
and/or real-tim
oftware can prov
osition within the
cording to a mo
For the sake of
terest into the Sa
to the Tools Lib
nd robot manipu
e robot models i
rred to the assem
eveloped librarie
Screenshots of the
sponsible for se
uage (STL) CAD
are packages; it
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tive procedure;
the robot Tool C
, are transferred
software. It cont
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th type has seve
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tion of robot po
and the reception
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time path corre
rovide a viable p
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Samples Librar
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ries.
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setting the sce
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it is widely use
on of the part of
; the operator
l Centre Point (
ed into the start-
ntains the neces
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veral characteris
(scanning step,
that allows stre
positional feedb
tion of feedback
aced with the so
rrection. Moreo
le pathway towar
king envelope.
tecture based on
the software co
rary. The probes
Robot Cell Libr
arate libraries ex
ots Library or to
cells defined in
raries.
scene of the pa
The STL format
sed for rapid pr
of interest withi
can select up
t (TCP) to the
-up module.
cessary algorithm
in tool-path type
eristic settings th
ep, speed, offsets
streaming of the
dback. Since th
ck coordinates,
software platfor
reover, the com
ards automatic
on four module
contains five lib
bes, sensors and
ibrary can conta
exist for the en
to the environm
in the Robot Ce
path-planning p
at was chosen b
prototyping and
thin the virtual m
p to 10 referenc
he real points. T
thms to generate
pes are being im
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the command
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ommunication
tic recognition
ules: start-up,
libraries. The
nd tools to be
ntain multiple
environments
nments in the
Cells Library.
project. The
n because it is
and computer-
l model of the
ence points of
. The relative
ate the desired
implemented:
good level of
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The ev
other CAD
robotic ar
by the Un
KCT. The
point with
unsuitable
kinematic
three snap
inspection
of 100 mm
Finally
format are
execute th
approach
each line
control un
controller.
The ne
The insert
behind mu
from the
minimum.
interpolati
100mm/s,
commerci
It is us
situations,
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evaluation mod
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arms had initial
University of Sie
he open-source
ithin its worki
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tics function, ba
napshots of the
ion tool-path for
mm/s. The toolp
FIGURE 4. Sn
ally, the output m
are generated fo
the generated t
ch the starting po
ne merely contai
unit, shown by
ler.
new path-plann
sertion of multip
multiple robot s
he same externa
m. The maxim
lation cycle. Fo
/s, the maximum
rcial solutions th
usual for NDT
ns, generating s
be time consum
odule provides
nts included in
ially been based
Siena (Italy) in
ce code does no
rking envelope
the new softw
based on a geom
he recorded sim
for a given datum
lpath simulation
Snapshots of the
t module has be
for each tool-
d tool-path; the
point of the insp
tains 6 coordina
by the schema g
nning approach
ltiple packets of
t synchronizatio
rnal server com
imum misalignm
For example, f
um path mismat
s that use digital
T operators to d
g specific tool-p
uming and not v
es a full simula
in the robot cell
ed on open-sour
in 2011 [18]. How
not allow the se
e in 8 differen
tware applicatio
eometric approa
simulation video
tum surface. Th
ion of RoboNDT
the simulation vid
of the
been developed
-path. The firs
he second file co
inspection and re
inates (x, y, z, A
a given in Figur
ch paves the way
of coordinates
tion. Sending co
omputer enable
gnment would
for robots run
atch would be e
tal I/O signals fo
to double check
paths for all t
t very practical
ulation capabilit
ell. The implem
ource MATLAB
owever, a funda
selection of the
rent configuratio
tion that has a
roach, was there
deo acquired fr
The tool-path is
DT allows accur
video and of the re
he example target
ed to output the
irst file contains
contains the ne
retract from the
, A, B, C) to dr
ure 2, imports b
ay to supportin
in each line o
command coor
bles the path sy
d remain within
running in a 12
e equal to 1.2 m
for synchroniza
ck some suspect
ll the areas of in
cal. A MATLAB
ility of the prog
ementation of th
B code, the KU
damental proble
the robot configu
ations). This inc
a target to be a
erefore develope
from the Robo
is a raster scan
curate time appro
e real inspection to
et surface.
he results of the
ins all comman
necessary point
the endpoint. Th
drive the roboti
ts both files and
ting inspection t
e of the first co
ordinates simult
synchronization
thin the distanc
12 millisecond
mm. This wors
ization purposes.
ect areas of a pa
f interest throug
AB based path
ogrammed robo
f the full inverse
KUKA Control T
blem was observ
figuration (a six
inconvenience
e as flexible as
ped and implem
boNDT softwar
n with 50 mm p
proximation of s
n tool-path, for the
he computations
and coordinates
ints to set the in
These two files
otic arm to a sp
nd sends the co
n techniques tha
command file c
ultaneously to m
tion mismatch t
nce covered by
nds interpolatio
orst case scenari
es.
part, after an in
ugh commercia
th-planning mo
bot path togethe
rse kinematic m
l Toolbox (KCT
erved with the u
ix-axis robot can
made the KC
possible. A n
lemented. Figure
are and of the
pitch, executed
of scanning time
the datum surface
ns. Two text file
tes that the rob
initial and fina
es have very sim
specific pose. T
command data t
that require mult
e can become th
o multiple robot
h to be maintai
by the robots
tion cycle and
ario is much imp
initial inspectio
cial path-plannin
odule has been
ther with any
model of the
CT) produced
e usage of the
can reach any
KCT function
new inverse
ure 4 presents
the real robot
ted at a speed
me.
e
files in ASCII
obot needs to
inal motion to
simple syntax;
. The external
ta to the robot
ultiple robots.
the principle
bot controllers
tained to the
ts in a single
nd moving at
improved over
tion. For such
ning software
een purposely
-
developed
centre poi
returning
interpolate
simulation
controlling
acquisition
FI
The I
arms are p
To eva
measurem
distance m
the acquis
full surfac
The la
the sensor
used trian
ed to be integra
point (TCP) data
g to the point
lated to generate
ion of a raster s
ling the robot ar
tion module.
FIGURE 5. Scre
V
IntACom inspe
presented in T
evaluate the accu
ement probe wa
e measurement p
uisition module
face scan. The ca
laser sensor wa
sor span (accord
iangulation to m
grated into the
ata, received fro
int of interest a
ate the desired t
r sub-scan, befo
arm via the UD
Screenshot of the in
VALIDATI
spection system
Table 1.
TABL
Payload
Maximum
Max. rea
Max. spe
Number
Position
Controlle
Protectio
ccuracy of gene
was mounted on
t probe was cho
le. It was used t
e capability to co
was established
ording to dimen
measure distanc
e main GUI. Th
from the robot d
t and executing
d type of sub-sc
efore execution.
DP/IP Ethernet
e integrated path-
TION EXPE
em comprises tw
BLE 1. KUKA K
oad
imum total load
. reach
. speed
ber of axes
tion repeatabilit
roller
ection classificat
nerated paths fr
onto the end ef
hosen [20]. The l
d to continuousl
control the laser
ed as the robot to
ensional specifi
ance. It had a 10
The path-planni
t during the initi
ing what is call
scan tool-path:
on. Therefore th
net connection e
-planning modul
PERIMENTS
two KUKA KR
KR16 L6-2 princ
oad
bility
fication
from the MATL
effector of one
e laser distance
usly monitor the
ser sensor via th
t tool, setting its
cifications of sen
101.6mm detect
nning software a
nitial scan, in or
alled a sub-sc
th: raster, segme
the execution o
n established by
dule during the sim
TS PATH A
KR16 L6-2 robo
incipal specificati
KR16 L6-
6 kg
36 kg
1911 mm
2 m/s
6
-
and a reso
frequency
Raster
contour of
of 1.6m2.
constant s
command
cycles of
data samp
The la
Figure 6 s
speeds. Th
2mm.
During
due to fi
manufactu
principal s
A scan
IntACom
using ultra
Figure
inspection
water jet n
of the sam
across the
seen. The
flaw has b
esolution of 30.5
cy was equal to
ter scan paths w
r of the main ski
. Three separa
t speeds of 100
nd positions to
of 12 millisecon
mples for each ro
laser sensor dat
shows the reco
The results show
FIGURE
ing manufacture
fibre deviation
ctured compone
al source of erro
can image of a
m prototype sys
ltrasound pulse-
ure 7 shows the
ion system. The
et nozzles that pr
ample. The stan
the C-scan and
he sample conta
s been sized to b
0.5m. The mea
to 1250Hz.
s were generated
skin of a carbon
rate tool-paths
100, 200 and 3
to the robot con
onds. The samp
robot interpolat
data was mapped
ecorded maps of
how that the dev
RE 6. Maps show
ure, as the comp
ion, residual str
nent can be sev
rror of the experi
a curved reinfo
system and a su
-echo phased a
the Time of Fli
he IntACom rob
t provide suitabl
tandoff between
d equal to 0.6m
ntains some tape
o be 5mm wide a
easurement lase
ted through the
on fibre compos
ths were genera
300mm/s, resp
ontroller and rec
pling rate of th
lation cycle.
ped to the surfac
of difference be
eviation of the m
owing distance de
mposite part is r
stress and strai
several millimetr
eriment.
ND
nforced wing sk
suitable tool-pa
d array inspectio
Flight (TOF) C
robotic arms de
able water colum
en the water jet
.6mm. The skin
ape insert defects
e and the bigges
laser spot size w
he MATLAB ba
site material ae
erated to travel
espectively. The
received actual
the laser sensor
rface scan by co
between measu
e measured dista
deviation from th
s removed from
train [21]. The d
etres for large c
NDT RESUL
skin, manufactu
path generated
tion through a 5M
C-Scan of the
deploy end-effe
umns to support
et nozzle and the
in thickness var
ects, as indicated
gest 15mm.
was smaller tha
based software
l aerospace wing
el along equally
he C++ code o
al TCP coordina
sor was set to 25
comparing with
sured and theore
istance from the
theoretical TCP f
m the mould, th
e difference bet
e composite sam
ULTS
ctured with intr
ed by the Robo
a 5MHz 64 ele
he large curved
ffectors carrying
ort the ultrasonic
the sample was
varies across the
ted by the black
than 250m and
are and used to
inglet. The surfa
ally spaced traje
e of the acquisi
inates over the
250 Hz, resultin
ith the interpolat
oretical TCP for
he theoretical TC
P for different rob
, the part can exh
between the CA
samples [22] and
ntroduced flaws,
boNDT software
element probe (0
ed surface obta
ing ultrasonic tr
nic beams from
as set to 8mm.
the sample and
ck ovals in figur
and the maximum
to finely follow
rface of interest
ajectories (10mm
isition module
e Ethernet inter
lting in an avera
lated feedback c
for the three diff
TCP spans a ran
robot speeds.
exhibit a spring
CAD dimensio
nd this was foun
ws, was obtaine
are. The part w
(0.6 mm pitch).
btained with the
transducers, m
m the probes to
. The resolution
d the stiffeners
gures 7 and 8. T
um sampling
w the curved
st had an area
mm pitch) at
transmitted
terface within
erage of three
k coordinates.
different robot
range between
ng-back effect
sions and the
und to be the
ined using the
t was scanned
h).
the prototype
mounted into
to the surface
ion is uniform
ers are clearly
. The smallest
-
Figure
the collec
the screen
potential d
In mod
the inspec
structure.
complex p
present si
increasing
themselve
FI
ure 8 shows a cl
lected data throu
een; the A-Scan
al defects.
odern aerospac
pection and ver
re. Traditional N
x part shapes em
significant cha
ingly demanding
lves to bespoke
FIGURE 7. C-Sc
close up of the
rough visualizati
an section is at
FIG
ace manufacturi
verification proc
l NDT methods
employed in ae
hallenges. Trad
ng reduced cyc
ke Cartesian or C
Scan of the main
he first group of
ation of B-Scan
at the bottom.
FIGURE 8. Close
CO
turing, the increa
rocedures requi
ds such as ultra
aerospace struct
raditional manua
cycle times for t
r Cartesian plus
ain skin surface of
of defects. The
ans and the A-S
m. The B-Scan
ose-up of one of th
CONCLUSIO
reasing use of co
quired to ensure
ltrasonic testing
uctures, combin
nually delivered
r the inspection
lus rotation stag
of the aerospace
he GUI of the In
Scans. The B-
n is very usefu
f the defected reg
IONS
f composite mate
ure safe deploy
ing are fundame
ined with comp
red NDT is tim
ions undertaken.
tage mechanical
ce composite wing
IntACom softw
-Scan is given
eful to size the
egions.
aterials is introd
loyment of com
mental to such
mplex material p
time consuming
en. Although so
cal scanners, the
inglet.
ftware lets the u
en on the right h
e C-Scan featu
roducing new ch
omponents in t
h inspection. H
al properties of c
ing and manufa
some part geom
there are many i
e user analyze
t hand side of
atures and the
challenges in
the finished
However the
f composites,
ufacturers are
ometries lend
y instances of
-
complex geometry that make the use of 6 axis robot positioners highly attractive. Most existing off line
programming approaches are geared towards manufacturing processes, and lack the required flexibility for
application to delivery of NDT measurements. In particular the lack of conditional programming capability has been
identified as one of the key shortcomings in existing software. This is fundamentally important for 2 reasons. Firstly
composites manufacturing has higher part variability and deviation from CAD than encountered with traditional
materials. Secondly NDT processes often require local measurement refinement. These shortcomings have
motivated the authors to develop new MATLAB based robotic programming software specifically geared towards
NDT path planning applications.
The new software has been tailored to the generation of raster scan paths for inspection of curved surfaces by 6-
axis industrial robots, and in its current form represents the first iteration of a system designed to overcome the
issues with current OLP packages. The software is intended to be flexible and extensible to future systems and robot
developments. The output tool-path is not specific to robot programming language or hardware, so could be
deployed across a range of platforms. It has been explained how the execution of the calculated path by a robotic
arm, externally controlled through a C++ external control unit, can be beneficial for NDT inspections. The
developed NDT robot toolbox will ultimately assist NDT technicians to move from a component CAD file to the
actual physical inspection, without the need to use multiple pieces of software not optimized for robotic NDT
inspections. The commercial driver for this work is the need to increase NDT inspection throughput. This has been
identified clearly as a bottleneck in existing composite parts manufacture in aerospace industries. The new software
will contain specific functions tailored to generate several types of tool-paths for raster scans, segment scans or
single point inspections. The inclusion of an evaluation module, incorporating the inverse kinematics, allows the
user to have a real-time preview of the calculated path for a successive safe execution in the real robotic
environment.
Comparative metrology experiments have been undertaken to evaluate the real path accuracy of the toolbox
when inspecting a curved 1.6 m2 surface using a KUKA KR16 L6-2 robot. The results obtained via a precision laser
range meter have shown that the deviation of the distance between the theoretical TCP and a large aerofoil curved
surface spans a range between 2mm; the dominant source of this error being the deviation of the part from the
CAD model. For the current NDT application, this level of accuracy is sufficient as the intended NDT delivery is
accomplished using a water jet coupling approach. However more demanding NDT inspection requiring higher path
accuracy will demand individual component surface metrology measurement prior to NDT inspection.
In the future a fully developed software solution will support different types of robotic arm and robotic
environments. Additionally, the possibility to define custom robotic cells and equip the robotic end-effector with
several different probes is the aim for a more versatile software platform for robot deployed NDT. The ultimate goal
of the authors remains the simultaneous management of command coordinates, robot positional feedback and NDT
data by an integrated server application running on an external computer. This paves the way for the introduction of
intelligent novelty factors for the application of robotic NDT inspections. On-line monitoring and data visualization,
real-time path correction and versatile path amending approaches are just some of the possible opportunities.
ACKNOWLEDGEMENTS
This work was developed in partnership with TWI Technology Centre (Wales), University of Strathclyde
(Glasgow), the Prince of Wales Innovation Scholarship Scheme (POWIS) and by IntACom, a project funded by
Welsh Government, TWI, Rolls-Royce, Bombardier Aerospace and GKN Aerospace. Additional support was
provided with assistance from UK Research Centre in NDE (EP/F017332/1) and EPSRC Equipment Grant New
Imaging Systems for Advanced Non-Destructive Evaluation (EP/G038627/1).
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