the point clouds into the mine’s coordinate system. They 
reduced the density of the original point clouds from 
roughly 10 mm spacing (0.03 ft) to 5 cm (0.16 ft) to produce 
a more manageable dataset while preserving the accuracy 
of the model or subsequent calculations. 

The digital model depicted the rock surface of the tunnels 
and drifts. But the narrow tunnels are filled with structures 
and equipment that support the mine operations. These 
additional objects were captured as part of the scanning 
process, and the team created separate models of the vari-
ous pipes, conduits and other objects. These items could be 
handled as standard 3D surfaces and exported directly to 
CAD and major mining packages.

One of the primary applications for the model is computing 
volumes, and the team also conducted deformation analy-
ses to compare the as-built tunnels to design information. 
They could also use the models to detect potential safety 
issues due to deformation or subsidence in the tunnels.

The SDUST team’s work demonstrated the ability of 3D 
scanning to handle the industry’s demanding requirements. 
They combined efficient processes with fast measuring 
equipment to collect data with minimal disruption to nor-
mal mine operations. The tunnels are major components of 
the underground mine structure, and the ability to create 
accurate models contributes to mine safety and efficiency. 

A second benefit emerged in the utilization of the 3D 
models for mine planning and design. “The models from the 
Trimble system enabled the mine management to transform 
from manual to digital methods,” Wang said. “This intuitive 
model for design improves support for decision makers for 
high-efficiency operations.”  By comparing the scanned data 
with a tunnel’s design, engineers can confirm that the mine 
is progressing according to plan and verify that the volume 
of material moved agrees with design calculations.  

The third key point, Wang said, is the ability to provide 
detailed spatial data to specialized applications packages. 
Using traditional surveying, it can be difficult to produce 
comprehensive 3D models of tunnels and ore bodies. Be-
cause the Trimble FX system can generate data for use in 
CAD, the system can significantly increase the digital aspect 
of mine operations management. 

 At the completion of the one-year project, Wang's team had 
scanned and processed data for roughly 12 miles (20 km) of 
major tunnels. In addition to developing efficient approaches 
for the underground work, the team created procedures 
for data communications, office processing and export to 
specialized software packages. Their work will be a driver for 
continued development of China’s digital mines. 

The SDUST team established procedures for working in the hot, 
humid tunnels.

A 3D view illustrates a mine chamber with structural members 
modeled from the point cloud. 

Individual cross sections can be developed from the 3D scanning data.