While personal communications on a minesite is critical, the additional equipment and weight miners are forced to contend with hampers work.
Often bulky, and fairly heavy, mining communications equipment has not been known for its lightweight
To overcome this and give miners some relief, NL Technologies has developed a two way messaging and tracking device that is incorporated into their existing cap lamps, the Northern Light Cap Lamp, to service this communications need.
“This system has already been awarded a large project at the West Wallsend coal mine, which is set to
change mining,” NL Technologies Australia director Tim Haight told Australian Mining.
One of the most important features of the cap lamps is the tracking system and the infrastructure that was required to install it.
Haight told Australian Mining that the installation of the Wi-Fi required to run this system and the
unique tracking arrangement “will the largest deployment of Wi-Fi underground in the entire world.
“No one has ever done anything like this in a coal mine anywhere in the world,” Haight said.
Intrinsically safe and carrying EXIA approvals, the system consists of a number of overlapping Wi-Fi
hotspots that cover most of the mine.
These overlapping hotspots allow for real time tracking and monitoring of vehicles, as NL Tech “setup the
Wi-Fi system to communicate directly to a shearer at the coal face.”
It can also be used for continuous miners and other underground machinery such as coal shuttles.
An important aspect of this arrangement is the tracking and logging system for the machinery.
“We’ve implemented reverse tracking in the mine.
Whereas forward tracking entails logging people and machinery as they move past pre-set readers, reverse tracking sees the individually designated reader placed in the cap lamp,” Haight said.
As the reader is in the cap lamp and the tags are set along the walls of the mine, with the info constantly
being sent along the Wi-Fi system, “there has never been anything as accurate at this tracking system in underground mining.”
Each person and piece of equipment can be tracked individually as they make their way through the mine.
The RFID tracking system performs telemetry by configuring the tags to retrieve and send data such as mileage, fuel and temperature and equipment use, completely wirelessly.
The precision in this tracking and logging is almost of a GPS standard.
“To date, at the West Wallsend coal mine, we have tested the RFID tracking system to within two metres of accuracy, however we expect we could get it to within one metre,” Haight told Australian Mining.
The tags are water resistant and robust to handle the underground mine environment.
Vastly improving safety, the two way messaging system itself operates on the underground wireless network, and enables real time communication.
“You can check and send messages via the cap lamp battery unit to any one underground,” Haight said.
Consisting of three major parts the system is comprised of the Northern Light Digital (NLD) network, the
messenger cap lamp and the Northern Light Digital mine software.
From a range of pre-written messages, a miner can text another user, with the message transmitted
through the NLD network.
Messages are then managed by the NLD software which handles message storage, status and history
as well as the complete send and receive functionality.
The cap lamp contains an internal processor that is capable of sending, storing, and deleting messages.
It is able to send messages to individuals or entire groups, as well as assign priority to outgoing messages, which assists in improving emergency response times by allowing a rescue team to know the exact location of personnel within two metres.
The cap lamp has an easy to operate toggle switch to choose between messages; a scrollable back lit two line LCD display, as well as a new message indicator.
The software allows for an operator to search, using the RFID system, for either individual assets or groups, which have all been designated with their own unique tracking tag.
The location of assets can be viewed according to a particular site zone, subzone or even proximity to a certain tag reader.
An operator is also able to view stored history of any particular individuals such as their position, last
location, medical history and their current training quali¬fications.