IEEE Robotics & Automation Magazine - March 2012 - 41

taken in the proximity of the craters. Moreover, the best
period to perform such measurement campaigns is before or
during an eruption. By comparing data before and after an
eruption, it is possible to better understand the best precursors, thus allowing for a more precise prediction of the activity. Understanding the intensity and duration of lava flow
enables volcanologists to decide whether the population of a
specific area needs to be evacuated or if lava deviation
measures have to be performed. Also, the knowledge of
when and how a plume of volcanic ash will be emitted is useful for the advanced planning of route modifications, and if
need be, flight cancellations; thereby, this information can
help reduce inconvenience and discomfort to passengers.
In this article, we present some research activities performed in the Robotic Laboratory of the Dipartimento di
Ingegneria Elettrica Elettronica e Informatica (DIEEI) at the
University of Catania, Italy, concerning the adoption of
robots for measuring volcanic activity. Catania is located in
southern Italy on the Island of Sicily and is situated at the
base of Mt. Etna, Europe's largest active volcano. Etna has
been responsible for a number of big eruptions that have
destroyed or seriously damaged constructions, roads, and at
times villages, shutdown airport activity in the area, and on
some occasions, killed irresponsible tourists. In light of these
situations, we began to closely cooperate with researchers of
the Istituto Nazionale di Geofisica e Vulcanologia (INGV,
the Italian Institute of Geophysics and Volcanology) and
have since built several robot prototypes.
Interestingly, one of the first examples of robotic makers was the mythological God Hephaestus (whose ancient
Roman name was Vulcano). In the Homer epic poem "The
Odyssey," Hephaestus is cited as the builder of some
mechanical helpers for his workshop, which, according to
myth, was situated inside Etna. In our laboratory, situated
at Etna's base, we are, in a way, continuing this old tradition of combining the robotics with the study of volcanoes.
Importance of Robots
for Measurements in Volcanoes
The main goal of using robotic systems for volcanoes is to
reduce the level of risk involved for volcanologists who are
working too closely to volcanic vents during eruptive phenomena. The scenes that follow a volcanic eruption can
lead to some of the worst possible conditions on earth:
flows of lava, pyroclastic flows of hot mud, precipitation of
big and hot stones, and earthquakes with terrain fractures
are some of the typical events that take place in the areas
surrounding the craters. In the last few decades, several
volcanologists have misinterpreted signs indicating imminent eruptions and have thus lost their lives during
volcanic explorations. Consequently, volcanologists should
take precise safety precautions to avoid dangerous areas,
but from another point of view, their quest for information
and data often pushes them to put themselves in situations
of high risk. Therefore, one possible instrument that can
allow them to take measurements in dangerous situations

without risking their lives is a robot. This innovation in
volcanic risk assessment is going to be part of an integrated
risk management system, which will obtain an almost realtime early warning that, in turn, will allow Civil Protection
authorities to protect citizens from eruption catastrophes.
Our research activity did not only deal with robotics; we
needed to collaborate with several groups of volcanologists
about the best ways to solve related problems. In some cases,
the requirements were too complex or expensive, and in
others, simple solutions-not exciting from a roboticresearch point of view-were possible. Our goal is not to
simply design and build a new and original robot but,
instead, to realize suitable instruments for volcanologists.
Many types of measurements can be useful for research
regarding volcanic activity, but we have identified the most
important ones, and they are discussed here.
Visual
Visual measurement is capable of getting pictures and videos
within immediate proximity to the craters so as to better
understand the evolution of an eruption. Active volcanic craters and dome structures are usually subject to rapid changes
and often collapse under their own weight or as a result of
endogenous forces. These collapses can produce dangerous
pyroclastic flows or block erupting vents, leading to the presence of high-pressure gas, which can thus cause explosions.
Hence, the visual measurement of craters and domes is particularly useful in predicting dangerous eruptions.
Thermal Images
Thermal images allow volcanologists to better understand
the behavior and the evolution of an eruption, giving
further information with respect to traditional visual
images. Infrared (IR) cameras are widely adopted and are
necessary instruments to be carried onboard a robot.
Moreover, a thermal camera can also serve to read the
temperature of the path where the robot is going to move
in order for it to avoid riding over fumaroles or on recent
lava flow, which can thus destroy the system.
Gas Analysis and Sampling
The analysis of the gas ejected from volcanic vents is one
of the main indicators of volcanic activity. Gas emission
comes from inside the volcano, and its composition
shows the happenings in the depths of the earth. However, the emitted gas is at a high temperature and quickly
mixes with the atmosphere, thus changing its original
composition. As a result, a collecting system must be
capable of gathering or analyzing gas close to the vents.
Although there are remote systems that permit analyzing
the nature of the gas through spectral or similar analysis,
only a direct measurement can give a precise data concerning the gas composition.
Several environmental constraints must be taken into
account in the developmental phase of a robotic system
that is to be adopted in volcanic areas.
MARCH 2012

IEEE ROBOTICS & AUTOMATION MAGAZINE

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