Comparing the performance of mobile and static LiDAR in detecting underground rock deformation

Abstract

Accurate deformation monitoring is essential for ensuring structural stability in underground mining environments. This study, therefore, evaluates the performance of mobile and static LiDAR scanners in capturing and analysing rock deformation within a controlled underground mock mine. The point cloud data was collected pre-and post-deformation using both scanning platforms and was processed in the open source CloudCompare for registration, segmentation and deformation analysis. The comparative assessment focused mainly on point cloud characteristics, surface errors and deformation mapping accuracy. The comparative results show that static LiDAR has a higher point resolution and lower surface errors, while mobile LiDAR allows for rapid data acquisition with a broader spatial coverage. Deformation measurements obtained from both platforms show a strong correlation with the field measurements; this is confirmed by statistical analysis with 𝑅2 Values greater than 0.99. Furthermore, a paired t-test resulting in a p-value of 0.188 exceeded the commonly used threshold of 0.05, indicating no significant difference between the two methods. Moreover, a trade-off between accuracy and operational efficiency was identified; where static LiDAR ensures high data quality, it is constrained by occlusions and acquisition time. Meanwhile, mobile LiDAR is more adaptable to confined environments. These findings contribute to optimising LiDAR-based deformation monitoring strategies in underground mining, balancing precision, efficiency, and practical implementation.