The trial is part of the ACARP Landmark Longwall Automation Project (see related articles) that is developing the technology to automate a longwall.
The ability to monitor multiple data sets related to the shearer is a crucial challenge for increased automation. The future spin-offs into other aspects of operating are also profound, such as the ability to monitor and better control conditions underground.
Existing shearer communications systems are cable-based and only allow asynchronous serial transport of data. To access the full suite of information and data – such as intelligent sensors and video equipment – is beyond the capacity of these systems.
The Ethernet connection has provided the bandwidth required for the communications link between the longwall main gate and the shearer.
South Bulga has a “wired” Ethernet connection from the surface to the longwall main gate with optical fibre and category 5 Ethernet cabling (100base T) providing the physical connection.
The main issue to be overcome by the Landmark Project was the shearer-maingate Ethernet segment. Significant technology developments would be required to achieve Ethernet-grade communications over the shearer cable. A wireless Ethernet (802.11b) system was installed and trialled successfully on the longwall to provide constant communications to the shearer over the entire face length.
The success of this part of the project has shown that an underground Ethernet network can achieve a high level of reliability, even when extended wirelessly to moving equipment like a longwall shearer.
A more detailed article on the technical aspects of this installation is due to be published in the March 2003 edition of Australia’s Longwalls.