Professor Kantner has emphasised the importance of using UAVs for thermal imagery,
noting ‘the challenge for remotely sensing archaeological sites is to be able to see below
the ground. Archaeologists use a variety of proven techniques that are ground-based,
such as ground penetrating radar, magnetometry, and electrical resistivity, but those are
time-consuming and expensive to use, and they cover relatively little area. Archaeologists have also been successful at using airborne technologies such as LIDAR, and these
can often see through vegetation and cover vast areas (especially when satellite-based),
but they’re not so good at seeing small sites nor can their sensing penetrate soils. The
UAV-borne thermal cameras provide a nice balance of being able to see small sites covered with soil, and they record more area than ground-based approaches. Thermal cameras have been around for a long time, but UAVs can now provide the right combination
of altitude and speed to use thermal approaches most effectively’.
University of Bristol Archaeology PhD student, Stephen Gray, has also highlighted the
value of UAVs for aerial thermography. In response to the high degree of interest amongst
the UK archaeological community in the possibilities for UAV usage in the field, Stephen
has produced a ‘Guide to Good Practice’ for using UAVs in archaeological surveys. UAVs
outfitted with sensors have the ability to hone in on the fundamental basis of archaeology; the landscape and features buried beneath the ground. Information provided by
UAVs can also enable archaeologists to determine exactly where they should dig. Or as
Stephen has pointed out, ‘taking aerial photographs may mean we don’t have to dig.
Excavating is a last resort, as it destroys information. It may be that we can learn what we
want to learn from the UAV survey without excavating’.
The technical specifications of UAVs also hold a number of advantages for their implementation in archaeology. Octocopters provide the stable platform necessary to be able
to take very high-resolution images. Octocopters can also be controlled by on-board
GPS linked to laptop-based software, which can control a UAV’s flight plan in order to
systematically photograph the surface below.
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