Final tests of CLOSE-SEARCH: unmanned aerial platforms in search missions for lost people
Final tests of CLOSE-SEARCH: unmanned aerial platforms in search missions for lost people
The project CLOSE-SEARCH, lead by the Institute of
Geomatics (Spain), reaches its end presenting a unmanned vehicle prototype
conceived to detect people lost in difficult-to-access areas by means of the
body heat.
Using an advance navigation concept based on the European augmentation
system EGNOS and low-cost redundant inertial measurement units, the UAV (that
is, Unmanned Aerial Vehicle) scans areas determined by the Search-And-Rescue
(SAR) team –the scan is performed combining RGB and thermal vision: that means,
seeing and sensing the target. With almost
2 meters length, an
approximate weight of 75 kilos and capacity to carry up to
30 kilograms of
payload, the helicopter is complemented with a ground control station in which
two operators control the mission, not just the scanned surface but also
monitoring the status of the vehicle, and finally links with the emergency
teams in place by providing accurate positions of the sensed targets. This
concept can therefore be fully integrated in the actual SAR mission work flows.
The vehicle control is fully autonomous: given an alert and an initial
guess of the area where the person got lost, the SAR team defines the route to be
followed and the vehicle executes the take-off, search, return to base and
landing automatically. The Civil Protection Directorate of Catalunya (DGPC) participates
in the project leading the User Advisory Board, a group of experienced
end-users in the SAR field, in order to incorporate their experience in
real-life situations. The DGPC has also arranged the test sites for the tests
and demos in the project, as the one held just a week ago in the town of
Copons.
Innovation in the use of UAVs: robust navigation
and Beyond-Line-of-Sight communication
The Institute of Geomatics (IG) brings to the project a navigation
concept for unmanned platforms based on the fusion of various sensors: on one
side, a key component is the use of the GNSS satellite-based augmentation
system, European EGNOS, bringing position accuracy down to
1 meter in horizontal and
3 meters in vertical (95%)
and providing integrity, which is the fundamental measure of safety related to
navigation. The use of integrity for UAVs is novel and already some papers have
been published by IG in the frame if CLOSE-SEARCH. Another component of the
navigation system is the Redundant Inertial Measurement Units (RIMUs), brought
in by the École Polytechnique Federal of Lausanne, to investigate the use of
low-cost inertial technology, used in a robust configuration to fit the
high-safety degree of the navigation system. Finally, other sensors as
Barometric Altimeters and Magnetometers are used to provide height and attitude
control. The result is an unmanned platform featuring a low-cost, robust
navigation system which incorporates integrity as a measure of safety in
navigation. Another innovative aspect of the prototype is the use of Worldwide
Interoperability for Microwave Access (WiMAX) as a primary means for
communication between the UAV and the ground control station. The Asociación de
la Industria Navarra
(AIN), creators and operators of the base platform, bring this communication
technology to the project to demonstrate the validity of the so-called Beyond-Line-Of-Sight
(BLoS) communication (that is, communication which does not require physical
clearance between the emitter and the receiver). The use of such a technology
would allow the platform to operate in zones of terrain abruptness without restrictions
on the particular UAV-control station geometry. Such an approach is not yet
implemented in conventional UAVs, which at the present time are limited by
distance and obstacles.
Lower cost and risk, more applications and
functionalities
The use of unmanned aerial vehicles in SAR missions has become
consolidated during the last years, especially in vast, low populated areas
such as in
Canada or
Australia.
Generally, these systems are of less cost and the impact of a platform loss or
the risk to which human operators are exposed is lower than with its homologous
manned versions. During Katrina hurricane in
New Orleans
(2005) or the nuclear tragedy in
Fukushima
(2011), the unmanned vehicles were in charge to provide aerial imagery of the
scene, being able to approach much closer that ground teams or manned
helicopters and planes, or even flying restlessly during night. Particularly in
CLOSE-SEARCH, the nocturne operability was a strong and key requirement to be
demonstrated, as the users clearly identified its convenience and advantage
over other search means. Therefore, the Final Test Campaign covered this item
among others.
The Final Test campaign: demonstration of
end-to-end SAR service
During the first weeks of March, the final version of the prototype has
been tested and the main functionalities of the prototype have been
demonstrated. The first part of the testing campaign was carried on in the town
of
Copons, in
central Catalunya. In this location, the BLoS communication concept was tested
and several users were able to assess its performance in a real situation. In
addition, a search mission was simulated over a remote area: few persons were
hidden and the operators in ground had to identify those persons by means of
the imagery that the UAV sent to the station. Finally, these persons were
geo-referenced to know their exact locations. A second test was carried in
Pamplona to assess the capability
of the night operability of the prototype and capacity to sense targets also
during night.
The CLOSE-SEARCH project (www.close-search-project.eu),
funded by the European Comission under the 7th Framework Program, is
lead by the Institute of Geomatics and gathers Asociación de
la Industria Navarra
(www.ain.es), École Polytéchnique Fédéral de
Lausanne (www.epfl.ch), DEIMOS Engenharia (www.deimos.pt), Institut Cartogràfic de
Catalunya (www.icc.cat) and Direcció General
de Protecció Civil (www.gencat.cat).
