Under the
ASTRA
(Atmospheric Science Through Robotic
Aircraft) umbrella, the
MAVIS
project is in development with
the aim to equip a fleet of gliders with atmospheric instru-
ments (Sobester
et al.
, 2011 and 2012). Gliders are released
at high altitudes and during the auto-piloted descent, they
recover data for different purposes: weather forecasting, pol-
lution, aerosol monitoring, wind speed, temperature, and
turbulences among others.
Atmospheric measurements, including temperature,
humidity, and pressure were captured for data analysis in
Corrigan
et al.
(2008b) along an atmospheric profile at differ-
ent altitudes. The system was described in the Atmospheric
Instrumentation subsection. These data were combined with
other data sets coming from an aerosol analyzer and a particle
counter that provided measurements of albedo, atmospheric
solar absorption, heating rates in the visible (0.4 µm - 0.7 µm)
and broadband (0.3 µm - 2.8 µm) spectral regions using verti-
cally stacked multiple lightweight
UAVs
(Ramana
et al.
, 2007).
Finn and Franklin (2011) described a technique for moni-
toring the air temperature and wind fields in areas close to
the ground surface. Sound signals emitted by its engine were
transmitted using radio communications. Additionally, re-
ceivers placed on the ground captured signals coming directly
from the
UAV
. Differences based on the Doppler effect of both
signals allow for the temperature and wind measurements.
In an agricultural context, the potato late-blight pathogen
in the atmosphere has been tracked in Aylor
et al.
(2011) by
using a 3 m wing-span
UAV
, engine powered, equipped with
sporangia samplers mounted under the wings. Aerial concen-
trations of plant pathogenic spores at various distances from
a source of inoculum have been quantified to determine the
potential spread of a plant disease.
Berman
et al.
(2012) used the Off-Axis
ICOS
device to mea-
suring in-situ H
2
O, CO
2
, and CH
4
air concentrations, primarily
for greenhouse locations and influenced areas, with the pos-
sibility of its application to large forest and remote locations.
The fully assembled
UAV
device measures approximately 30.5
cm × 30.5 cm × 28 cm and weighs 19.5 kg.
Kroonenberg
et al.
(2012) measured the structure param-
eter of temperature in the lower convective boundary layer
with a mini-
UAV
. The
UAV
was a wingspan of 2 m and a maxi-
mum
TOW
of 6 kg.
Xie
et al.
(2013) proposed a monitoring atmospheric en-
vironment framework based on
UAVs
for emergency applica-
tions. They described the platform, instruments functions,
and procedures to carry-out such missions.
Gyongyosi
et al.
(2013) described a weather prediction sys-
tem based on a statistical model and learning-based methods.
The
UAV
, with a wingspan of 3.7 m, length 1.7 m, maximum
TOW
17 kg and payload about 4 kg captures actual climatolog-
ical data around an area and the forecast is provided accord-
ing to the data and the model. Weather research and predic-
tion is documented in the report provided by Darack (2012)
where several aircrafts and sensors are mentioned.
In the project described in Daehler (2014), an
UAS
was
equipped with a radar unit operating in
HF
and
VHF
ranges
for collecting data from the air and the surface of the ice in
Antarctica and Greenland.
Lin and Chen (2014) proposed the use of an autopilot
helicopter to study aerosol and ozone concentrations at low
altitudes.
Atmospheric concentrations of spores of fungi belonging to
the genus
Fusarium
were studied in Lin
et al.
(2014) by using
both a terrestrial system and
UAVs
. The fixed-wing
UAVs
ex-
plored the atmosphere in an agricultural ecosystem flying 100
m above ground level and equipped with aerobiological sam-
pling devices containing large plates of 9 cm diameter similar
to the ones used in Schmale
et al.
(2008) and Lin
et al.
(2013).
The goal was to study variations with height and season and
how transport distances vary between seasons from potential
inoculum sources.
Cultural: Heritage and Archeology
Cultural heritage and archeology are two topics, sometimes
very close to each other and sometimes indistinguishable.
Both are related to human activity in the past.
UAVs
are con-
sidered useful tools for inspection in heritage and archeologi-
cal applications. Yan
et al.
(2012) discussed advantages and
shortcomings of photogrammetry at low altitudes from
UAVs
in architectural heritage applications. They assumed that the
complexity of architectural heritages determines the particu-
larity of aerial photogrammetry. Also Remondino
et al.
(2012)
concluded that, in cultural heritage,
SfM
methods suffer from
lack of reliability and repeatability when complex and long
sequences of data are processed.
Cultural Heritage
Eisenbeiss
et al.
(2005 and 2006), and Eisenbeiss and Zhang
(2006) analyzed the generation of DSM in the cultural heritage
site of Pinchango Alto, Peru, based on multi-image matching
and registration techniques in overlapped images. The images
were acquired with an autonomous helicopter equipped with
a commercial digital camera, and the results compared against
a laser-based ground technique.
A quad-rotor, with empty weight of 585 g, maximum
payload capacity of 200 g and equipped with a
CMOS
-based
sensor, was the platform used in Hendrickx
et al.
(2011) for
heritage documentation, based on photogrammetry, in the
Tuekta area, in the Russian Altay Mountains. The goal was
to obtain two types of products: photogrammetric (
DEMs
and
ortho-images) and archaeological datasets (3
D
visualisation
and volume estimations).
Gini
et al.
(2012) used two digital compact cameras for
acquisition of
RGB
and
NIR
images onboard a quad-rotor; the
last one modified with a filter that allows the radiation with
wavelength greater than 830 nm, with weights of 130 g and
250 g, respectively, for 3
D
modeling and tree classification in
the Parco Adda Nord, (Italy).
Brumana
et al.
(2013) presented a work oriented to build
panoramic images for heritage simulation purposes in areas of
interest. Images acquired from the
UAV
were combined with
data from ground sensors with the aim of forming the pan-
oramic setup. The
UAV
platform was a helicopter with an over-
all weight of 7.3 kg, main rotor diameter 1,564 mm, and a 7 kg
payload. A digital camera installed on a mechanical stabilizer.
Candigliota and Immordino (2013a and 2013b) described
some technological issues for data acquisition in real-time
for monitoring cultural heritage. Three applications were ad-
dressed: landslide of a hill affecting a historic village center,
knowledge acquisition of a historical building for restoration,
and damage evaluation after the Emilia-Romagna earthquake.
They used a helicopter and a quad-copter equipped with
stabilized platforms to hold the camera.
Koutsoudis
et al.
(2014) evaluated the performance of the
SfM
and dense multi-view 3
D
reconstruction techniques for
high building 3
D
models. An
UAV
was equipped with a three
axis pan-tilt-roll remote controlled digital camera head. The
SfM
approach was applied to the reconstruction of an Ottoman
monument located in the region of Xanthi, Greece and com-
pared against a time-of-flight terrestrial 3
D
range scanner.
Archaeology
Early on, the use of
UAVs
in archaeology was considered as
promising (Schlitz, 2004). In archaeological explorations,
photogrammetric techniques are commonly used for analysis
and inventories, where 3
D
models (
DSMs
and
DTMs
), mapping,
mosaics or ortho-images are typical photogrammetric prod-
ucts of special interest in archaeology. In addition, thermogra-
phy was applied in this application.
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April 2015
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