The influence of the operating environment on manual and automated load-haul-dump machines: a fault tree analysis

The automated load-haul-dump (LHD) machines have the potential to increase productivity and improve safety, but there are many issues to be considered when optimising the operation of LHDs. Today's focus on improved equipment reliability is part of the problem, and another difficult issue is the special conditions and constraints of the operating environment. For automated LHDs, the latter issue is even more important, as humans have been removed from the production area and are not close by to solve the problems. The purpose of this paper is to find the causes of LHD idle time and to study their impact on the operation of LHDs. In this study, real-time process data and maintenance data from an underground mine in Sweden have been refined and integrated. The study takes into account the complexity of the mine environment, discusses the factors to be considered when optimising and automating the operation and uses fault tree analysis (FTA) to analyse the idle time.