The active mine environment is completely different from
closed or conserved mine environments, i.e. conditions in
which we tested the use laser scanning before (Kuda et al.
2014). Darkness, dust, high humidity and high temperature
limit device deployment underground.
The most limiting factor in active coal mine is dustiness.
The fine dust could damage delicate and precise laser optics.
In addition, low visibility affects the speed of scanning. With
decreasing visibility, performance of device also decreases.
Conditions of reduced light in respect to the darkness and
dustiness causes poor targeting. The targets are highly visible
to a distance of 10e15 m.
The fogging scanner optics due to high humidity and
temperature is also a problem. Waiting time for temperature
equalisation may be more than 30 min.
It should be pointed out, that the authors are fully aware
that the used device is not primarily designed for direct using
in mines and in similarly extreme conditions. Therefore its
use was accompanied by series of preventive precautions
(preventing the penetration of the dust into the device,
condensation on the device, etc.).
Another problem is the technology in mining works. The
larger is the object in front of the scanner, the greater is the
area behind the objects that will not be scanned. The same
applies to the distance of that object. The closer the object is to
the scanner, the greater the area that will not be scanned.
These problems are evident in the vicinity of coalface, when
due to deformation and decreasing of the mining work profile
everything is in close range to the scanner (see Fig. 9).