A Surface Adaptive First-Look Inspection Planner for Autonomous Remote Sensing of Open-Pit Mines

TL;DR

The paper addresses autonomous surface inspection in active open-pit mines where the mine-face evolves over time. It proposes a two-layer framework combining an operator-defined initial route with an online view-planner that uses instantaneous $3$D LiDAR data and a modeled sensor footprint to predict a horizon-$N$ inspection path and adapt view-poses under photogrammetric constraints like $d_{view}$, $d_{hov}$, and $d_{vov}$. The First-Look component computes $X_{ref}^{k+1}$ from $P_{nn}^k$ and $X_{odom}^k$ using unit vectors aligned with the surface and camera FoV to maintain forward yaw while keeping roll/pitch minimal. Experiments in simulation on Feiring-Bruk and outdoor hardware trials demonstrate accurate surface reconstruction (mean cloud-to-cloud error $0.256$ m, max $1.667$ m) and robust adaptation to changing mine-face morphology, validating a practical approach for high-quality remote sensing in dynamic mining environments.

Abstract

In this work, we present an autonomous inspection framework for remote sensing tasks in active open-pit mines. Specifically, the contributions are focused towards developing a methodology where an initial approximate operator-defined inspection plan is exploited by an online view-planner to predict an inspection path that can adapt to changes in the current mine-face morphology caused by route mining activities. The proposed inspection framework leverages instantaneous 3D LiDAR and localization measurements coupled with modelled sensor footprint for view-planning satisfying desired viewing and photogrammetric conditions. The efficacy of the proposed framework has been demonstrated through simulation in Feiring-Bruk open-pit mine environment and hardware-based outdoor experimental trials. The video showcasing the performance of the proposed work can be found here: https://youtu.be/uWWbDfoBvFc

Figures (8)

• Figure 1: A functional representation of the evaluated mission architecture for open-pit mine face inspection.
• Figure 2: A graphical representation of the modelled photogrammetric characteristics utilized for horizontal (Fig. \ref{['fig:cam_charac']}(a)) and vertical overlap (Fig. \ref{['fig:cam_charac']}(b)).
• Figure 3: A run-time snapshot of the predicted inspection path (in green) being generated during the simulation of mine-face inspection of the Feiring-Bruk open-pit mine.
• Figure 4: A visual presentation of the 3D simulation environment based on the open-pit Feiring-Bruk mine for evaluation of the proposed inspection framework.
• Figure 5: A collage composed of run-time snapshots taken during the simulated run at the Feiring-Bruk mine. Fig. \ref{['fig:sim_collage']}(1) presents the initial operator-defined high-level reference waypoints indicated as maroon spherical markers. Fig. \ref{['fig:sim_collage']}(2) captures the aerial platform en-route to the first waypoint marker upon mission initialization. The traversed route of the UAV is shown via bold orange line. Figures. \ref{['fig:sim_collage']}(3)-(4) capture the behaviour of the aerial platform during inspection of the open-pit mine face. The observed regions of the mine-face during inspection are shown as green markers.