AGRICULTURE
Surface mining
GNSS information is being used to efficiently manage the mining of an ore body and the movement of waste material. GNSS equipment installed on shovels and haul trucks provides position information to a computer-controlled dispatch system to optimally route haul trucks to and from each shovel. Position information is also used to track each bucket of material extracted by the shovel to ensure that it is routed to the appropriate location in the mine (crusher, waste dump, leach pad). Position information is used by blast hole drills to improve fracturing of the rock material and control the depth of each hole that is drilled to keep the benches level. Multi-constellation GNSS is particularly advantageous in a surface mining environment due to the obstructions caused by the mine’s walls: more satellites means more signal availability.
Not only is GNSS positioning being used to optimize operations within the mine, but it is also enabling automated road trains for safer, more efficient mine-to-port transport.
An article (Perception, Positioning and a Long Haul Approach to Autonomy) about how GNSS is used for autonomous platooning in an Australian iron ore mine is in the 2022 Velocity magazine available at: resources.hexagonpositioning.com/perception-positioning-long-haul
Automated blast hole drilling
Automated drills are used in surface mines to increase safety and productivity. A single operator safely located in the control room can operate and monitor up to five automated drills.
The blast holes drilled by the automated drills must be very precise, both horizontally and vertically. The position of the holes (horizontal accuracy) is critical in controlling rock fragmentation. Rock fragments that are too large or too fine can increase wear on the rock crushers used to process the material. Hole depth (vertical accuracy) is important for creating a flat bench.
Three GNSS technologies are used on the automated drills: RTK, heading and multi-constellation. RTK provides the precise positioning needed to accurately locate the blast holes. Heading provides the alignment of the drill to ensure the holes are drilled perpendicular. Multi-constellation receivers compensate for signal blockages common in the high wall environment typical of surface mines.
An article (The Pit, The Bit and The Benefit) about how GNSS is used in automated drilling is in the 2013 Velocity magazine available at: resources.hexagonpositioning.com/pit-bit-benefit.
