Evaluating Underground Mining Equipment Line-of-sight and Augmented Vision

Power haulage accounts for the greatest number of fatalities in Canadian, Australian, American, Indian, and Spanish mines, and is the fourth leading cause of fatal accidents in underground African mines. However, this rate is expected to grow with a move toward increased power haulage and less manual labour in Africa. Many of the fatal injuries have been associated with load-haul-dump (LHD) operation due to their notoriously poor line-of-sight (LOS) hampered by a sideways-seated operating position. To date, modifications to cabs, engine profiles, buckets, lights and, installation of rotated seats, have led to only moderate LOS gains. This case study reviews several approaches for LOS evaluation including computer simulation methods like the LOS boxplot. The benefits of a secondary viewing device to augment operator visibility are presented. A four-camera system was evaluated in a field trial. Placement of cameras to maximize LOS was determined on-site using field methods, and enhanced with immediate feedback provided by a custom written computer-based LOS assessment program. Prior to camera installation a 1.7m tall pedestrian was first visible to the LHD operator ~5m in front of the bucket, ~6m behind the engine and over 12m from the front right corner. With the optimized four camera placement and moderate operator head and trunk movement, a 360-view immediately around the LHD to a standing pedestrian height was realized. This case study provides further support for an augmented viewing system to improve operator LOS and illustrates the benefits of using computer-based options to evaluate LOS improvements.