What is a Wireless Mesh Sensor Network & How is it Used in Mines?

As mines become larger, deeper and operate at a faster pace than in the past, accurate monitoring becomes increasingly important.

Collecting data from a range of geotechnical instruments that are often spread over a wide geographical area can be a challenge, especially if the data collection has to be performed manually.

In order to increase efficiency and to have data available quickly and with minimal effort, it makes sense to link geotechnical monitoring devices to an electronic network. This allows for data to be moved rapidly and accurately to a central point, where it can be interpreted and used effectively.

The most efficient type of network for this purpose is a Wireless Mesh Sensor Network. A basic network of this type contains a few key elements:

• Geotechnical, hydrology or other mine monitoring instruments (sensors).
• Wireless nodes (remote terminal units); for example the MDT-RTU. Up to 3 sensors can be connected simultaneously via lead wires to each RTU, which then communicate wirelessly with other nodes nearby.
• One or more Ethernet or Leaky Feeder Gateways. These devices receive data from one or more wireless nodes (RTUs) and feed it to the mine’s existing Ethernet or Leaky Feeder infrastructure.
• A software control system (for example, MDT’s MineMonitor and MineHop packages). This software assimilates and interprets the data received from sensors located inside the mine, and then makes it available to engineering staff via the mine’s IT infrastructure, using a standard web browser. Since the data is stored in an SQL database, it can also easily be accessed by any 3rd party applications that the mine may already use.

This type of structure is referred to as a “mesh” network because each wireless node (remote terminal unit) relays data to other nearby nodes, forming an overlapping “mesh” of data acquisition wherever multiple nodes are in range of each other.