IAES
Inter
national
J
our
nal
of
Robotics
and
A
utomation
(IJRA)
V
ol.
15,
No.
3,
September
2026,
pp.
589
∼
596
ISSN:
2722-2586,
DOI:
10.11591/ijra.v15i3.pp589-596
❒
589
Cost-awar
e
global
fr
ontier
matching
f
or
R
OS
2
multi-r
obot
exploration
Chu
V
an
Cuong,
T
ran
T
uan
Anh
A
V
iS
Lab,
Posts
and
T
elecommunications
Institute
of
T
echnology
,
Hanoi,
V
ietnam
Article
Inf
o
Article
history:
Recei
v
ed
May
2,
2026
Re
vised
Jul
23,
2026
Accepted
Aug
6,
2026
K
eyw
ords:
Cost-a
w
are
allocation
Frontier
allocation
Global
matching
Multi-robot
e
xploration
P
ath
o
v
erlap
R
OS
2
ABSTRA
CT
Multi-robot
frontier
e
xplor
ation
supports
w
arehouse
mapping
and
inspection
robotics,
b
ut
geometric
assignment
can
produce
o
v
erlapping
motion
and
inef-
cient
tar
get
pairing.
This
paper
presents
a
R
OS
2
frontier
-allocation
layer
that
combines
a
weighted
frontier
cost
with
global
one-to-one
matching.
The
study
isolates
global
matching
from
sequential
assignment
while
k
eeping
the
cost
for
-
mulation
and
R
OS
2
e
x
ecution
stack
x
ed.
Three
policies
are
e
v
aluated
on
tw
o
indoor
maps,
four
team
sizes,
and
three
seeds.
Across
72
completed
main-polic
y
runs,
global
matching
gi
v
es
the
l
o
west
mean
completion
time,
tra
v
elled
distance,
path
o
v
erlap,
and
assignment
conict.
Relati
v
e
to
sequential
cost-based
assign-
ment,
it
reduces
compl
etion
time
by
24.3%,
tra
v
elled
distance
by
14.2%,
and
path
o
v
erlap
by
65.8%,
with
lo
wer
nal
co
v
erage
under
the
same
stopping
rule.
The
results
support
a
coordination-ef
cienc
y
benet
in
the
tested
R
OS
2
sim-
ulations;
broader
claims
require
lar
ger
,
heterogeneous,
dynamic,
and
ph
ysical
deplo
yments.
This
is
an
open
access
article
under
the
CC
BY
-SA
license
.
Corresponding
A
uthor:
Anh
T
ran
T
uan
Posts
and
T
elecommunications
Institute
of
T
echnology
Hanoi,
V
ietnam
Email:
anhtt@ptit.edu.vn
1.
INTR
ODUCTION
Autonomous
e
xploration
lets
mobile
robots
b
uild
maps
before
na
vig
ation,
inspection,
or
aut
omation
tasks.
In
industrial
robotics,
it
supports
AMR/A
GV
w
arehouse
mapping,
production-oor
inspection,
and
digital-twin
preparation.
Frontier
-based
e
xploration
selects
goals
at
the
boundary
between
kno
wn
free
space
and
unkno
wn
space
[
1
]
,
and
multi-robot
e
xtensions
use
shared
information
to
coordinate
complementary
re-
gions
[2],
[3].
The
central
problem
is
assigning
useful
frontiers
without
redundant
team
motion.
A
nearby
tar
get
may
still
be
poor
if
another
robot
is
mo
ving
to
w
ard
the
same
cluster
or
if
the
path
o
v
erlaps
in
a
corridor
.
Prior
w
ork
sho
ws
that
cost,
information
g
ain,
o
v
erlap
reduction,
task-allocation
mechanisms,
and
frontier
-detection
ef
cienc
y
all
af
fect
team
beha
vior
[4]-[10].
Recent
w
ork
has
broadened
the
allocation
design
space
in
se
v
eral
directions.
V
oronoi
and
parti
tion-
based
methods
distrib
ute
robots
across
dif
ferent
spatial
re
gions,
sometimes
combined
with
reinforcement
learn-
ing
to
reduce
duplicate
e
xploration
[11]-[14].
Learning-based
and
h
ybrid
planning
approaches
modify
frontier
selection
or
path
generation
to
impro
v
e
e
xploration
beha
vior
in
structured
en
vironments
[15]-[17].
Other
stud-
ies
emphasize
trajectory
planning,
auction-style
task
al
location,
and
deadlock
beha
vior
in
multi-robot
systems
[18]-[21].
Benchmark-dri
v
en
system
e
v
aluation,
utility-v
alue
allocation,
and
multi-resolution
frontier
scoring
J
ournal
homepage:
http://ijr
a.iaescor
e
.com
Evaluation Warning : The document was created with Spire.PDF for Python.
590
❒
ISSN:
2722-2586
further
sho
w
the
need
to
assess
e
xploration
by
more
than
nal
co
v
erage
alone
[22]-[25].
These
studies
pro
vide
important
components,
b
ut
man
y
comparisons
change
the
frontier
score,
assign-
ment
mechanism,
and
e
x
ecution
stack
together
.
This
paper
therefore
studies
a
narro
wer
g
ap:
whether
global
one-to-one
mat
ching
impro
v
es
team
coordination
when
the
frontier
score,
frontier
source,
and
R
OS
2
stack
are
x
ed.
The
linear
assignment
solv
er
is
standard;
the
contrib
ution
is
the
e
v
aluated
allocation
layer
.
The
main
contrib
utions
are:
−
A
R
OS
2
e
xploration
pipeline
in
which
the
allocation
layer
combines
distance,
acti
v
e-tar
get
repulsion,
robot-specic
skip
memory
,
information
g
ain,
and
spatial
dispersion
before
Na
v2
goal
e
x
ecution.
−
A
controlled
comparison
of
geometric
proximity
assignment
(GP
A),
sequential
cost-based
assignment
(RSA),
and
cost-a
w
are
global
matching
(RGM),
with
distance-only
,
distance–g
ain,
partition-based,
auction-
style,
and
no-dispersion
references.
−
A
simulation
e
v
aluation
o
v
er
tw
o
indoor
maps,
four
team
sizes,
and
three
seeds,
using
completion
time,
nal
co
v
erage,
tra
v
elled
distance,
co
v
erage
ef
cienc
y
,
assignment
conict,
and
path
o
v
erlap.
The
e
vidence
is
limited
to
the
tested
indoor
simulations;
deplo
yment-scale
claims
require
lar
ger
,
dynamic,
heterogeneous,
and
ph
ysical
tests.
2.
THE
PR
OPOSED
METHOD
2.1.
System
ar
chitectur
e
The
R
OS
2
pipeline
inputs
per
-robot
pos
es,
local
SLAM
maps,
a
mer
ged
occupanc
y
grid,
candidate
frontiers,
and
acti
v
e
tar
gets.
It
outputs
at
most
one
na
vig
ation
goal
per
a
v
ailabl
e
robot.
Figure
1
summarizes
the
data
o
w
.
LiD
AR
and
odometry
update
local
SLAM
maps,
local
maps
are
mer
ged,
frontier
clusters
are
e
xtracted,
a
robot-frontier
cost
matrix
is
b
uilt,
and
selected
goals
are
sent
to
Na
v2.
Na
v2
feedback
updates
acti
v
e-tar
get
and
skip-memory
states
before
the
ne
xt
allocation
c
ycle.
SLAM,
map
mer
ging,
and
l
ocal
na
vig
a-
tion
are
standard
components;
the
paper
focuses
on
scoring
and
matching.
Figure
1.
R
OS
2
e
xploration
pipeline
with
cost-a
w
are
allocation
2.2.
Cost-awar
e
fr
ontier
scor
e
Let
R
=
{
r
1
,
.
.
.
,
r
m
}
be
the
set
of
a
v
ailable
robots
and
F
=
{
f
1
,
.
.
.
,
f
n
}
be
the
set
of
candidate
frontiers.
F
or
robot
r
i
and
frontier
f
j
,
the
allocator
uses
the
follo
wing
combined
cost:
C
ij
=
w
d
ˆ
d
ij
−
w
a
A
j
−
w
s
S
ij
+
w
g
G
j
−
w
p
P
ij
(1)
where
lo
wer
v
alues
are
preferred.
The
terms
encode
distance,
acti
v
e-tar
get
cro
wding,
robot-specic
skip
mem-
ory
,
frontier
-cluster
g
ain,
and
spatial
dispersion.
IAES
Int
J
Rob
&
Autom,
V
ol.
15,
No.
3,
September
2026:
589–596
Evaluation Warning : The document was created with Spire.PDF for Python.
IAES
Int
J
Rob
&
Autom
ISSN:
2722-2586
❒
591
Each
frontier
candidate
is
represented
by
a
cluster
centroid
c
j
on
the
mer
ged
occupanc
y
grid.
Dis-
tances
are
measured
in
the
shared
map
frame.
The
implementation
uses
the
follo
wing
c
ycle-le
v
el
normaliza-
tion:
norm(
z
)
=
z
−
z
min
z
max
−
z
min
+
ε
,
(2)
where
z
min
and
z
max
are
computed
o
v
er
v
alues
a
v
ailable
in
the
current
allocation
c
ycle.
The
constant
ε
=
0
.
1
a
v
oids
di
vision
by
zero
and
is
k
ept
x
ed
across
all
maps,
team
sizes,
and
compared
policies.
The
terms
are
instantiated
as
ˆ
d
ij
=
d
ij
max
k
,l
d
k
l
+
ε
(3)
A
j
=
norm
X
a
∈
T
act
I
(
∥
c
j
−
c
a
∥
2
<
ρ
a
)
∥
c
j
−
c
a
∥
2
+
ε
!
(4)
S
ij
=
I
(
f
j
∈
H
skip
i
)
(5)
G
j
=
|
Q
j
|
max
k
|
Q
k
|
+
ε
(6)
P
ij
=
norm
X
k
̸
=
i
1
∥
c
j
−
p
k
∥
2
+
ε
(7)
where
d
ij
is
the
Euclidean
distance
from
robot
pose
p
i
to
centroid
c
j
,
T
act
is
the
set
of
acti
v
e
tar
gets,
H
skip
i
is
a
per
-robot
skip
memory
,
and
Q
j
is
the
set
of
grid
cells
in
frontier
cluster
f
j
.
The
same
parameter
set
is
used
for
all
maps,
team
sizes,
and
methods,
as
summarized
in
T
able
1.
Acti
v
e-tar
get
and
skip-memory
parameters
are
x
ed;
sensiti
vity
analysis
is
left
for
future
w
ork.
T
able
1.
Allocation
parameters
P
arameter
V
alue
Role
ε
0.1
A
v
oids
di
vision
by
zero
in
normalization
ρ
a
3.0
m
Acti
v
e-tar
get
repulsion
radius.
w
d
,
w
a
,
w
s
,
w
g
,
w
p
w
d
=
0
.
4
,
w
a
=
0
.
2
,
w
s
=
0
.
1
,
w
g
=
0
.
2
,
w
p
=
0
.
3
Same
cost
weighting
across
all
non-ablation
cost
policies.
Frontier
representation
cluster
centroid
One
candidate
tar
get
per
frontier
cluster
Allocation
mode
batch
dispatch
A
ne
w
assignment
is
issued
when
a
v
ailable
robots
can
recei
v
e
goals
RGM
solv
er
Hung
arian
linear
sum
assignment
One-to-one
global
matching
o
v
er
the
current
cost
matrix
2.3.
Assignment
policies
and
complexity
Three
main
assignment
congurations
are
e
v
aluated.
GP
A
is
the
geometric
reference
polic
y
and
as
-
signs
frontiers
using
nearest-distance
preference.
RSA
applies
the
combined
cost
in
(1)
sequentially
,
assigning
robots
one
by
one
according
to
the
currently
lo
west
a
v
ailable
cost.
RGM
uses
the
same
cost
matrix
as
RSA
b
ut
solv
es
all
a
v
ailable
robot-frontier
pairs
jointly
as
a
one-to-one
assignment.
F
or
RGM,
the
binary
v
ariable
x
ij
equals
one
when
robot
r
i
is
assigned
to
frontier
f
j
in
the
current
allocation
round:
min
x
ij
m
X
i
=1
n
X
j
=1
C
ij
x
ij
,
(8)
s.t.
n
X
j
=1
x
ij
≤
1
,
∀
i,
(9)
Cost-awar
e
global
fr
ontier
matc
hing
...
(Chu
V
an
Cuong)
Evaluation Warning : The document was created with Spire.PDF for Python.
592
❒
ISSN:
2722-2586
m
X
i
=1
x
ij
≤
1
,
∀
j
,
(10)
x
ij
∈
{
0
,
1
}
.
(11)
The
rst
constraint
allo
ws
each
a
v
ail
able
robot
to
recei
v
e
at
most
one
frontier
,
and
the
second
pre
v
ents
duplicate
assignment
of
the
same
frontier
in
one
round.
Cost-matrix
construct
ion
requires
O
(
mn
)
e
v
alua-
tions.
The
Hung
arian
solv
er
operates
on
the
rectangular
matrix
after
padding
when
needed,
and
the
dominant
assignment
step
scales
cubically
in
the
lar
ger
matrix
dimension.
3.
METHOD
3.1.
Simulation
setup
and
pr
otocol
Experiments
are
conducted
in
a
R
OS
2
simulation
en
vironment
using
the
same
SLAM,
map-mer
ging,
frontier
-detection,
and
Na
v2
na
vig
ation
stack
for
all
compared
policies.
The
allocator
is
the
only
component
changed.
The
benchmark
contains
tw
o
indoor
maps:
Map
1
is
a
cluttered
open-space
layout
of
approximately
12
m
×
10
m
,
and
Map
2
is
a
structured
layout
of
approximate
ly
15
m
×
10
m
with
partial
partitions.
The
conguration
can
be
seen
in
T
able
2.
T
able
2.
Simulation
and
measurement
conguration
Item
Conguration
used
in
all
compared
policies
Platform
R
OS
2
Humble,
Gazebo,
homogeneous
T
urtleBot3
Bur
ger
robots,
0.26
m/s
nominal
max-
imum
speed,
simulated
2D
LDS-01
LiD
AR
with
360
◦
vie
w
and
0.12–3.5
m
range.
Mapping/frontiers
SLAM
T
oolbox
2D
LiD
AR
SLAM;
mer
ged
occupanc
y
grid
at
0.05
m/cell;
frontier
cells
ha
v
e
a
free
4-neighbor
,
clusters
use
8-neighbor
BFS,
S
min
=
0
.
5
m,
and
centroid
tar
gets.
Protocol/metrics
Shared
Na
v2
settings
for
all
policies;
st
ops
at
0.90
co
v
erage,
no
reachable
frontier
with
all
robots
idle,
timeout,
or
f
atal
f
ailure;
d
c
=
1
.
5
m
and
0.05
m
o
v
erlap
grid.
The
main
comparison
e
v
aluates
GP
A,
RSA,
and
RGM
with
3,
4,
5,
and
6
robots
and
seeds
0,
2,
and
4,
yielding
24
completed
runs
per
polic
y
.
P
aired
comparisons
use
the
same
map,
seed,
and
robot
count.
Across
seeds,
map
geometry
,
robot
model,
sensor
range,
softw
are
stack,
and
parameters
remain
x
ed;
the
seed
changes
only
small
start-pose
perturbations
and
tie-breaking
among
equal
or
near
-equal
frontier
priorities.
Extended
analysis
uses
the
same
protocol
for
GGM,
DGM,
PN
A,
A
U
A,
and
RGM-noD.
T
w
o
no-dispersion
no-data
runs
are
e
xcluded,
with
no
outlier
remo
v
al.
All
policies
use
the
same
LiD
AR
SLAM,
map
mer
ging,
frontier
clustering,
and
Na
v2
conguration.
A
run
is
completed
when
no
feasible
frontier
remains
and
all
robots
return
to
idle.
Run-le
v
el
metrics
are
completion
time,
nal
co
v
erage,
total
distance,
co
v
erage
ef
cienc
y
,
ass
ignment
conict,
and
path
o
v
erlap.
Assignment
conict
is
the
fraction
of
assignment
rounds
in
which
an
y
pair
of
goals
is
closer
than
d
c
=
1
.
5
m
or
belongs
to
the
same
frontier
cluster
κ
t
i
=
κ
t
k
.
P
ath
o
v
erlap
rasterizes
TF/odometry
trajectories
onto
a
0.05
m
grid
and
computes
|{
q
:
n
(
q
)
≥
2
}|
/
|{
q
:
n
(
q
)
≥
1
}|
,
where
n
(
q
)
is
the
number
of
robots
visiting
cell
q
.
Lo
wer
conict
and
o
v
erlap
indicate
less
t
ar
get
cro
wding
and
less
repeated
tra
v
ersal.
W
e
report
mean
±
standard
de
viation
and
paired
W
ilcoxon
tests
o
v
er
matched
map,
seed,
and
robot-count
settings.
4.
RESUL
TS
AND
DISCUSSION
4.1.
Main
policy
comparison
T
able
3
summarizes
the
main
comparison.
RGM
gi
v
es
the
lo
west
mean
completion
time,
tra
v
elled
distance,
assignment
conict,
and
path
o
v
erlap
among
the
three
main
policies,
while
achie
ving
the
highest
co
v
erage
ef
cienc
y
.
Its
trade-of
f
is
lo
wer
nal
co
v
erage
than
GP
A
under
the
same
stopping
rule,
so
the
claim
is
coordination
ef
cienc
y
rather
than
co
v
erage
dominance.
T
able
3.
Main
polic
y
comparison
Polic
y
Description
T
ime
(s)
Co
v
.
Dist.
(m)
Ef
f.
Conict
Ov
erlap
GP
A
Geometric
proximity
assignment
240.40
±
51.56
0.940
±
0.011
80.3
4
±
9.24
1.345
±
0.159
0.340
±
0.162
0.024
±
0.018
RSA
Sequential
cost-based
assignment
232.45
±
47.50
0.912
±
0.005
81
.24
±
10.39
1.336
±
0.152
0.302
±
0.127
0.027
±
0.020
RGM
Proposed
cost-a
w
are
global
matching
176.05
±
34.75
0.896
±
0.021
69.6
9
±
7.47
1.549
±
0.114
0.250
±
0.157
0.009
±
0.012
IAES
Int
J
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&
Autom,
V
ol.
15,
No.
3,
September
2026:
589–596
Evaluation Warning : The document was created with Spire.PDF for Python.
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Rob
&
Autom
ISSN:
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❒
593
Compared
with
RSA,
RGM
reduces
mean
completion
time
from
232.45
s
to
176.05
s
(24.3%),
total
distance
by
14.2%,
and
path
o
v
erlap
by
65.8%.
Compared
with
GP
A,
it
reduces
completion
time
by
26.8%,
distance
by
13.3%,
and
path
o
v
erlap
by
62.2%.
Co
v
erage
ef
cienc
y
increases
to
1.549
m
2
/m.
The
W
ilcoxon
tests
in
T
able
4
support
the
ef
cienc
y
claim.
RSA
slightly
increases
o
v
erlap
relat
i
v
e
to
GP
A
(0.027
vs.
0.024),
whereas
RGM
lo
wers
it
to
0.009,
indicating
that
the
sequential
greedy
mechanism,
not
the
composite
cost
itself,
causes
this
de
gradation.
RGM
signicantly
reduces
time
and
distance
relati
v
e
to
GP
A,
RSA,
GGM,
A
U
A,
and
PN
A;
o
v
erlap
reduction
is
signicant
ag
ainst
GP
A,
RSA,
and
A
U
A.
T
able
4.
W
ilcoxon
paired
tests
Comparison
T
ime
∆
(%,
p
)
Distance
∆
(%,
p
)
Ov
erlap
∆
(%,
p
)
RGM
vs
GP
A
-64.358
(26.8%,
<
0
.
001
)
-10.650
(13.3%,
<
0
.
001
)
-0.015
(62.2%,
0.003)
RGM
vs
RSA
-56.408
(24.3%,
<
0
.
001
)
-11.552
(14.2%,
<
0
.
001
)
-0.018
(65.8%,
0.001)
RGM
vs
GGM
-64.013
(26.7%,
<
0
.
001
)
-6.218
(8.2%,
0.003)
-0.003
(21.8%,
0.363)
RGM
vs
A
U
A
-60.388
(25.5%,
<
0
.
001
)
-7.404
(9.6%,
<
0
.
001
)
-0.012
(56.6%,
0.010)
RGM
vs
PN
A
-65.287
(27.1%,
<
0
.
001
)
-2.604
(3.6%,
0.360)
-0.004
(31.1%,
0.355)
Figure
2
sho
ws
that
RGM
is
f
aster
,
tra
v
els
less,
and
reduces
repeated
tra
v
ersal.
RSA
can
commi
t
early
robots
to
locally
attracti
v
e
tar
gets
and
le
a
v
e
later
robots
with
poor
team-le
v
el
choices;
RGM
e
v
aluates
assignments
jointly
.
The
lo
wer
nal
co
v
erage
under
RGM
is
therefore
interpreted
as
an
ef
cienc
y
trade-of
f
under
the
current
stopping
rule.
Figure
3
illustrates
the
trajectory-visualization
format
for
GP
A,
RSA,
and
RGM
runs.
Quantitati
v
e
o
v
erlap
claims
remain
based
on
T
ables
3–4
and
Figure
2.
Map 1
Map 2
0
50
100
150
200
250
300
Completion T
ime (s)
Map 1
Map 2
0
20
40
60
80
100
T
otal Distance (m)
Map 1
Map 2
0.00
0.01
0.02
0.03
0.04
0.05
0.06
P
ath Overlap R
atio
GP
A
RS
A
RGM
Figure
2.
Main
quantitati
v
e
comparison
for
GP
A,
RSA,
and
RGM
Figure
3.
T
rajectory
visualization
used
for
qualitati
v
e
inspection
of
the
three
main
policies
Cost-awar
e
global
fr
ontier
matc
hing
...
(Chu
V
an
Cuong)
Evaluation Warning : The document was created with Spire.PDF for Python.
594
❒
ISSN:
2722-2586
4.2.
Extended
baselines
and
ablation
T
able
5
compares
RGM
with
solv
er
-isolation
and
e
xternal-style
references.
GGM
isolates
d
i
stance-
only
global
m
atching,
DGM
adds
information
g
ain,
PN
A
approximates
partition/V
oronoi-style
nearest-frontier
assignment,
A
U
A
approximates
utility
auction
allocation,
and
RGM-noD
remo
v
es
dispersion.
These
same-
stack
baselines
are
not
full
reimplementations
of
all
auction
or
V
oronoi
methods
[5],
[7],
[8],
[11]-[14].
RGM
is
f
aster
than
all
listed
v
ariants
and
has
t
he
lo
west
mean
distance
e
xcept
for
the
non-signicant
dif
ference
relati
v
e
to
PN
A.
T
able
5.
Extended
baselines
and
no-dispersion
ablation
Polic
y
Description
Runs
T
ime
(s)
Dist.
(m)
Conict
Ov
erlap
RGM
Proposed
cost-a
w
are
global
matching
24
176.05
±
34.75
69.69
±
7.47
0.250
±
0.157
0.009
±
0.012
GGM
Distance-only
global
matching
24
240.06
±
76.96
75.91
±
7.91
0.370
±
0.177
0.012
±
0.012
DGM
Distance–g
ain
global
matching
24
253.31
±
101.93
75.43
±
12.01
0.258
±
0.154
0.014
±
0.016
PN
A
P
artition-based
nearest-frontier
assignment
24
241.33
±
58.94
72.29
±
7.59
0.252
±
0.167
0.013
±
0.014
A
U
A
Auction-style
utility
assignment
24
236.43
±
92.35
77.09
±
10.24
0.320
±
0.173
0.021
±
0.016
RGM-noD
RGM
without
spatial
dispersion
term
22
222.04
±
48.78
77.81
±
9.82
0.297
±
0.146
0.011
±
0.009
Ag
ainst
PN
A,
RGM
has
nearly
the
same
conict
rate
(0.250
vs.
0.252)
and
a
non-signicant
distance
dif
ference,
b
ut
reduces
completion
time
by
27.1%
(
p
<
0
.
001
).
Ag
ainst
A
U
A,
RGM
reduces
completion
time
by
25.5%,
distance
by
9.6%,
path
o
v
erlap
by
56.6%,
and
mean
conict
from
0.320
to
0.250.
These
comparisons
support
the
narro
wer
claim
that
the
tested
global
matching
layer
is
more
time-ef
cient
than
the
implemented
partition-
and
auction-style
basel
ines
under
the
same
simulator
,
frontier
source,
and
Na
v2
stack.
Relati
v
e
to
GGM,
RGM
reduces
time
by
26.7%
and
distance
by
8.2%,
so
the
g
ain
is
not
from
matching
alone.
RGM-noD
further
suggests
that
dispersion
helps
reduce
time,
distance,
and
conict,
although
acti
v
e-tar
get
and
skip-memory
sensiti
vity
is
not
e
v
aluated.
4.3.
Industrial
implications
and
limitations
The
allocation
layer
is
rele
v
ant
to
w
arehouse
mapping,
smart-f
actory
commissioning,
sensor
-dri
v
en
inspection,
and
digital-twin
mapping,
where
repeated
tra
v
ersal
increases
time
and
ener
gy
use.
The
e
xperiments
remain
simulation-only
,
with
tw
o
indoor
maps
and
homogeneous
teams
of
up
to
six
robots;
dynamic
obsta-
cles,
sensor
noise,
communication
delay
,
heterogeneous
platforms,
and
ph
ysical
eets
remain
future
v
alidation
tar
gets.
A
natural
ne
xt
step
is
learning-based
frontier
selection
upstream
of
the
x
ed
global
matching
layer
.
5.
CONCLUSION
This
paper
presented
a
R
OS
2
frontier
-allocation
layer
that
combines
weighted
cost
scoring
with
global
one-to-one
matching.
Across
72
main-polic
y
runs,
RGM
achie
v
ed
the
lo
west
mean
compl
etion
time,
distance,
path
o
v
erlap,
and
assignment
conict
among
GP
A,
RSA,
and
RGM,
while
impro
ving
co
v
erage
ef
cienc
y
.
Rel-
ati
v
e
to
RSA,
it
reduced
completion
time
by
24.3%,
distance
by
14.2%,
and
path
o
v
erlap
by
65.8%,
with
lo
wer
nal
co
v
erage
under
the
same
stopping
rule.
Future
w
ork
will
study
lar
ger
maps,
dynamic
obstacles,
sensor
noise,
heterogeneous
eets,
communication
delays,
learning-based
frontier
selection,
and
ph
ysical
deplo
yment.
A
CKNO
WLEDGMENTS
The
authors
thank
A
V
iS
Lab
for
its
research
en
vironment
and
support.
FUNDING
INFORMA
TION
Authors
state
no
funding
in
v
olv
ed.
A
UTHOR
CONTRIB
UTIONS
ST
A
TEMENT
This
journal
uses
the
Contrib
utor
Roles
T
axonomy
(CRediT)
to
recognize
indi
vidual
author
contrib
u-
tions,
reduce
authorship
disputes,
and
f
acilitate
collaboration.
IAES
Int
J
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&
Autom,
V
ol.
15,
No.
3,
September
2026:
589–596
Evaluation Warning : The document was created with Spire.PDF for Python.
IAES
Int
J
Rob
&
Autom
ISSN:
2722-2586
❒
595
Name
of
A
uthor
C
M
So
V
a
F
o
I
R
D
O
E
V
i
Su
P
Fu
Chu
V
an
Cuong
✓
✓
✓
✓
✓
✓
T
ran
T
uan
Anh
✓
✓
✓
✓
C
:
C
onceptualization
I
:
I
n
v
estig
ation
V
i
:
V
i
sualization
M
:
M
ethodology
R
:
R
esources
Su
:
Su
pervision
So
:
So
ftw
are
D
:
D
ata
Curation
P
:
P
roject
Administration
V
a
:
V
a
lidation
O
:
Writing
-
O
riginal
Draft
Fu
:
Fu
nding
Acquisition
F
o
:
F
o
rmal
Analysis
E
:
Writing
-
Re
vie
w
&
E
diting
CONFLICT
OF
INTEREST
ST
A
TEMENT
Authors
state
no
conict
of
interest.
INFORMED
CONSENT
Not
applicable
because
the
study
uses
simulation
e
xperiments
and
does
not
in
v
olv
e
human
parti
ci-
pants.
ETHICAL
APPR
O
V
AL
This
study
uses
simulation
e
xperiments
and
does
not
in
v
olv
e
human
participants
or
animals.
D
A
T
A
A
V
AILABILITY
Deri
v
ed
metrics
and
conguration
details
are
a
v
ailable
from
the
corresponding
author
upon
reasonabl
e
request.
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Cost-awar
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...
(Chu
V
an
Cuong)
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596
❒
ISSN:
2722-2586
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BIOGRAPHIES
OF
A
UTHORS
Chu
V
an
Cuong
is
a
lecturer
at
Posts
and
T
elecommunications
Institute
of
T
echnology
,
Hanoi,
V
ietnam.
His
interests
include
IoT
,
embedded
systems,
R
OS
2
robotics,
and
autonomous
multi-robot
e
xploration.
Email:
cuongcv@ptit.edu.vn.