They work with remotecontrol devices that change the direction, position and speed of a German-made cutting machine that slices back and forth along a 300-metre-wide coal face.
Automatic target tracking laser transmitter applicated in remote car is a very important part of laser positioning, position coordinates of remotecontrol car can be drawn.
The "living" will place itself on the transformable, remotecontrol openable stairs, that flatten themselves when being in "up" position and become regular stairs when going down.