The Load-Haul-Dump (LHD) equipment consists of a center-articulating vehicle with a bucket at its front end and is used exclusively for the excavation, transportation, and dumping of ore within underground mines. Seismogenic stoping extraction conditions entail deep, highly stressed geological regions that undergo constant rock removal and experience seismic activity because of mining activities like rockbursts.
In such highly stressed areas underground, the exposure of human beings to possible dangers that come with seismic activities is totally unacceptable as far as operational risk is concerned. Tele-operated and autonomous fleets of LHD machines help eliminate the risk of ground collapses in mining activities. This technology ensures that operators are not exposed to possible dangers at drawpoints but instead operate from control rooms that are structurally stable above or underground.
The first engineering challenge for the teleoperated LHDs operation is setting up the reliable communication system characterized by a broad bandwidth and low latency. To perform teleoperation, one should have the opportunity to continuously receive real-time data, including live video footage, machine diagnostics information, and control commands (Theissen et al., 2023). Since underground settings have characteristics such as poor visibility, EM interference, and several tunnel geometries, mining companies have to adopt multilayer communication networks, which are often built on either industrial Wi-Fi or 5G and fiber-optic networks.
Autonomous navigation and ore loading inside the drifts involve special sensors and autonomous loading algorithms. To perform shared autonomy principles, teleoperated LHDs use LiDAR, stereo vision, and specific software. For instance, LHDs can autonomously move to rock piles, calculate how to approach them, and perform intermittent tilt commands to load a bucket while requesting help from the operator only when there are some unexpected situations (Tampier et al., 2021).
The operation of these machines within seismically active stopes further necessitates the ruggedization of the LHDs and its nodes along with their integration with geotechnical monitoring systems. The system must be capable of handling the dust, water, and shock waves generated due to micro-seismic activity. In many modern tele-remote systems, operational data of LHD is fed into the digital systems of the mine to keep a correlation between the operation of the machine and ground pressure/rock stress measurements (Long et al., 2024).
In summary, the use of remote controlled LHDs within seismically active stopes is an engineering task which requires the integration of mechanical engineering, telecommunications engineering, and software engineering. Through building a robust network system, designing intelligent shared autonomy systems for the vehicle, and integrating all the fleets with real-time geotechnical monitoring systems, mining can continue to produce high levels of extraction output without compromising the safety of the miners.
References
Ferguson, G., Cuello, D., Moreno, P., Potvin, Y., & Valdivia, E. (2018). Strategy for research and development in the cave mining industry. Proceedings of the Fourth International Symposium on Block and Sublevel Caving, 487-498. https://doi.org/10.36487/acg_rep/1815_37_ferguson
Long, M., Schafrik, S., Kolapo, P., Agioutantis, Z., & Sottile, J. (2024). Equipment and Operations Automation in Mining: A Review. Machines, 12, 713. https://doi.org/10.3390/machines12100713
Tampier, C., Mascaró, M., & Ruiz-del-Solar, J. (2021). Autonomous Loading System for Load-Haul-Dump (LHD) Machines Used in Underground Mining. Applied Sciences, 11, 8718. https://doi.org/10.3390/app11188718
Theissen, M., Kern, L., Hartmann, T., & Clausen, E. (2023). Use-Case-Oriented Evaluation of Wireless Communication Technologies for Advanced Underground Mining Operations. Sensors, 23, 3537. https://doi.org/10.3390/s23073537
