High Resolution Imagery Collection for Post-
Disaster Studies Utilizing Unmanned Aircraft
Systems (UAS)
Stuart M. Adams, Marc L. Levitan, and Carol J. Friedland
Abstract
This paper examines the use of unmanned aircraft sys-
tems (UAS) to capture imagery for use in post-disaster
field studies at the neighborhood and individual building
level. A discussion of post-disaster imagery collection
including satellite, aerial, and ground-based platforms is
first presented. Applications of UAS in recent disasters as
described in the literature are then surveyed, and a case
study investigating UAS capabilities for imagery collec-
tion following an EF-3 tornado in northern Alabama on 02
March 2012 is presented. Case study considerations include
the multi-rotor unmanned aerial vehicle (UAV) equipment
and ground station, onboard imagery devices, flight con-
siderations and capabilities, and imagery and metadata
collection capabilities of the UAS. Sample post-tornado
imagery of building damage is shown, demonstrating the
order of magnitude improvement in imagery resolution
compared to traditional post-disaster aerial photography.
Introduction
Damage assessments following disaster events are often
performed using imagery acquired through satellite, aerial,
and ground-based (vehicle-mounted and handheld) platforms,
which can be analyzed using visual, spectral, and photo-
grammetric techniques. Satellite and aerial imagery covers
large geographical areas but are of limited use for detailed
investigations of individual buildings and neighborhoods due
to spatial resolution limitations. Additionally, while such
imagery is usually available following large disasters such as
the Joplin, Missouri, tornado in 2011 and Hurricane Sandy in
2012, it may not be readily available following smaller events.
Imagery for use in studies of the performance of the built
environment at individual building and neighborhood levels
has mainly been obtained by handheld and, more recently,
vehicle-mounted cameras. A significant limitation of vehi-
cle-mounted systems is that they are best at collecting images
of the street facing side(s) of the building. Side views may
or may not be available depending on proximity of adjacent
buildings, and views of the rear face of the building are gener-
ally not available unless the neighborhoods have alleys. Trees,
shrubs, and fences create interference for vehicle-mounted
cameras. These elements can also create interference for
handheld cameras, but to a lesser extent than the aforemen-
tioned obstacles since the photographer has more flexibility
in selecting a vantage point. When access to a damaged build-
ing is possible, handheld cameras are often used to acquire
imagery inside the building and from the roof of the building,
to obtain a much fuller understanding of the damage. Imagery
collected from the roof, especially roofs of taller buildings,
can show damage to adjacent buildings as well. However, in
some instances, buildings are too damaged to enter safely.
Ground-based imagery acquisition (both handheld and vehi-
cle-based) can be hindered by site access limitations, includ-
ing: downed trees, power lines, and other debris blocking the
roads; roads washed out by storm surge or inland flooding;
law enforcement roadblocks; private property and privacy
considerations; and physical security considerations for the
ground-based damage survey team.
The limitations of existing satellite, aerial, and ground-
based imagery platforms also create difficulties when as-
sessing building damage caused by different hazards. For
example, storm surge damage to the walls and interior of a
building in cases where the roof remained intact may not
be visible from nadir (vertical) satellite and aerial imag-
ery. Earthquake-induced collapses where the roof remains
largely intact may similarly be difficult to identify from nadir
imagery (Gerke and Kerle, 2011). Wind damage to flat or low
slope roofs may not be observable from ground based imagery.
Additional information on capabilities and limitations of the
different imagery platforms are discussed by Adams
et al
.
(2010).
Recent advances in
UAS
flight and flight control capabili-
ties and in digital camera technologies, coupled with substan-
tial reductions in the costs of both, have positioned
UAS
as
platforms of interest for post-disaster studies.
UAS
provide a
user-controlled means to collect imagery from multiple angles
at neighborhood and individual building scales.
UAV
-mount-
ed camera systems have the capability to capture still and
video imagery from vertical and oblique perspectives at much
higher resolutions than currently available from commercial
satellite and aerial photography (Nebiker
et al
., 2008).
UAS
also have capabilities to overcome common site access and
image collection limitations of ground-based platforms.
UAS
platforms can thus potentially fill a significant gap in current
Stuart M. Adams is with the Department of Civil and Envi-
ron-mental Engineering, Louisiana State University, 3418
Patrick F. Taylor Hall, Baton Rouge, LA 70803 (sadam15@lsu.
edu).
Marc L. Levitan is with the National Windstorm Impact Re-
duction Program, Engineering Laboratory, National Institute
of Standards and Technology, 100 Bureau Drive, Gaithersburg,
MD, 20899 (
).
Carol J. Friedland is with Bert S. Turner Department of
Con-struction Management, Louisiana State University, 3128
Photogrammetric Engineering & Remote Sensing
Vol. 80, No. 12, December 2014, pp. 1161–1168.
0099-1112/14/8012–1161
© 2014 American Society for Photogrammetry
and Remote Sensing
PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING
December 2014
1161
