| This research developed two audit procedures to assess line-of-sight for the load-haul-dump (LHD) operator. The visibility audit and target audit was performed in the simulated, computer environment. Modifications to various machine components showed improvements in line-of-sight and increased visible area (by as much as 15%) around the virtual machine. The tested components that were shown to improve visibility include cab design with greater window openings, thinner light posts and light brackets, triangular bucket lip, lowered back/engine profile, minimized mud guards and minimized cylinder covers. General recommendations for sign height and driving scenarios were also provided to increase visibility awareness in the underground environment.; Subsequently, a seat rotation intervention was appraised in the virtual environment in an effort to improve posture while also improving line-of-sight. Results revealed that a seat rotation of 20 degrees provided reductions in joint force, muscular asymmetry and joint angles while 45 degrees provided even greater postural benefit. There was a concurrent increase in the number of visual attention locators that were observed. (Abstract shortened by UMI.)... |
