GPS Applications in Coal Industry
GPS entered the Mining Industry as a fast, and cost-effective
instrument for survey. A shifting landscape is the very nature of
mining operations; as shovels and dozers remove coal and ore, they
reshape the mine’s surface. Real-time GPS allows mining operations
to keep on top of these constant changes and provide updated
operating instructions to heavy equipment operators. In addition,
GPS systems provide a fast and accurate solution for replacing and
maintaining control points and calculating the volume of material
moved.
Moving mining assets, including dozers, shovels, graders and
draglines, are managed and guided using advanced GPS technology.
Advanced GPS systems also track and monitor the status and location
of dump trucks, providing reports to their heading and velocity as
well as the size of the truck’s load. Live GPS is becoming
commonplace for monitoring and dispatching haul trucks or drills
and for providing grade control on shovels. These data can also be
tied to a GIS to monitor the location of all equipment, in real time.
GPS being an all-weather real time, continuously available,
economic and very precise positioning technique , would have wide
range of applications in Indian coal industry. The potential areas
for usage of GPS in Indian coal industry includes –
Surveying
Several modern surveying techniques like Satellite Remote Sensing,
Photogrammetric, Field surveying procedures using digital
theodolites, short and long range EDM instruments like Total Station
etc., are available today. However, the advantages of using the
satellite based GPS techniques for surveying are:
- GPS measurements do not require inter-visibility between points whereas the conventional surveying tools require line of sight for measurements.
- GPS technique provides a three dimensional position for the point. That is in one go, we get the horizontal and vertical position of the point, unlike in conventional surveying where we need two operations viz., horizontal traverse for planimetric control and a level loop for height control.
- A very high accuracy measurement can be made in a relatively short time for baseline lengths of a few hundred meters to few hundred kilometers and can provide the same accuracy anywhere on earth, in almost any weather condition and at any time of the day.
GPS offers many advantages compared with conventional
survey methods. Because there is no need for a rod person, each
surveyor can work alone when necessary. GPS also requires much
less setup time than did traditional surveying equipment, so the crew
can use its time more efficiently. It can also keep a much more
flexible schedule and move from one area to the next or one pit to
another as needed.
Opencast Mine Operations
The entire opencast mine earthmoving process can be monitored
and enhanced by GPS equipped heavy earth mining machinery
(HEMM). Computerized mine operations management system would
include tracking of mining equipment, maintenance, monitoring
and diagnostic systems, transmission of loading instructions to
dumpers etc for better control.
The System Network
Basically the requirement comprises of mounting the GPS instrument within the HEMM/equipment operator’s cabin with an antenna alongside to facilitate receipt of satellite signals. GPS is integrated with the Graphical Operator Interface Console which in turn has a receiver (infra-red) attached on the sides of the equipment that enables relay of information to the central computer located in the control/mine manager’s office at a distant place from the mine. Using a multidirectional radio, each vehicle’s onboard computer sends GPS-based position information back to a dispatch computer, which corrects the data.
This computer monitors the location and status (full or empty,
heading, and velocity) of each vehicle in the fleet. The system
analyzes production statistics, such as haul routes, historic data
about drive time to a specific shovel location, and cycle time —
how long it takes to make a round trip from the shovel to the dump
site and back. The system then correlates these data to most
efficiently route all the vehicles.
By having real-time access to each vehicle’s position, the
dispatch system can determine if several trucks are waiting at one
shovel and, if so, route them to a different shovel. This helps
prevent bottlenecks and keeps operations moving freely. The
dispatch computer can also determine the most efficient location
for the truck to dump its load at any given time.
Essential Features of truck monitoring system -
- Satellite reciever
- Radio repeater tower ( ground reference station)
- Central control room
- Truck / drill HEMM based antenna
- Radio base station
Operator’s Feedback and System Response
After the truck operator unloads as assigned, the dispatch computer can give the driver his or her next assignment — determining at which pit the truck is needed and whether the operator will haul overburden or coal, depending on the mine’s needs. At the administration building, human dispatchers can view on their 21- inch computer screens the data from any DGPS-fitted support equipment. For example, if mine personnel should need a motor grader or water truck sent to their area, a dispatcher could identify the nearest appropriate machine and dispatch it to the area by way of a voice radio, further optimizing truck use.
Optimization Models
- Mine topography
- Road network
- Pit configuration
- Truck availability
- Coal blending / bands excavation schedules
- Dumping grounds distances
- Real time travel times
- Spare part mgmt
- HEMM downtime mgmt
- Reassignment evaluation of HEMM