02 May 3D Laser Scanning for Underground Operations

Technology has been changing over the years and has drastically changed how surveyors collect data for mapping purposes. Traditional survey techniques have proven to be very accurate over time, however, collecting data using such methods can be time consuming on large scale projects, where production and accuracy cannot be compromised. One of the best ways to be productive on site and render accurate data is through 3D laser scanning. 3D laser scanners have flooded the surveying market, especially for mass data capturing and ensuring collection of critical surface details being scanned. But how about we explore a little of 3D laser scanning in the underground mining operations?

Accurate Reality Capture

Though the Topcon GLS 2000 laser scanner is not intrinsic safe, it can be deployed in other underground mining operations that do not require an intrinsic safe surveying instrument for underground mass data collection. The Topcon GLS 2000 3D laser scanner supports various surveying methods such as the “occupy and backsight” (a traverse-like functionality that makes it possible to set up the instrument on a known point i.e., control point), sight to a prism set up on another known point for geo-referencing purposes and lastly, to get the most accurate scan data. Furthermore, this type of workflow makes the processing of raw data much easier with the semi-automated point cloud registration, upon importing the data into the Magnet Collage software, a much needed functionality for working on large scale projects, where accuracy is a standard requirement.

Importance of Underground Scanning

Underground scanning is important to understand the behaviour of walls, to check if there is movement or not. 3D laser scanning provides solutions in understanding any form of deformation in the underground space. This is done by regularly scanning the walls to check if there is any deformation or analysis of stress on the pillars, as well as the rate with which the deformation is happening, to be able to make informed decisions and remove employees from potentially hazardous areas of work. In the case of reopening the mining operations underground, it would be ideal to carry out a full scan of the existing shaft.

Monitoring deformation requires accuracy and with the Topcon GLS 2000’s occupy and backsight functionality, you can maintain the consistency of accuracy by using the same control/known points onsite.

WorldsView had the privilege of being invited to partake in the underground 3D laser scanning of the Merensky Pillar of the Royal Bafokeng Maseve mine, in the North West Province in Rustenburg.

We completed the scan using the Topcon GLS 2000 3D laser scanner. We had to use the scan targets for accurately registering the point cloud from different scan stations. The raw data was seamlessly processed using the Topcon Magnet Collage software.

Conclusion

Mapping has certainly evolved over time. This evolution has occurred through the application of different technological solutions, from using Total Station workflows for understanding the geometry of the underground working environment, to using the 3D laser scanners for detailed underground mapping and understanding the changes that might occur in the walls underground.