Abstract
Forest harvest simulations provide an opportunity for the forest engineering community to design and evaluate harvesting operation equipment on desk computers under variable terrain, environmental, and economic constraints. This capability influences the effectiveness of harvest unit design in office environment. When designing harvest units for ground-based harvesting systems, it is important to incorporate challenging design parameters that reflect real-world practice. Therefore, the facial validity of forest harvest simulations is critical when used for educational purposes. This study compared the performance limits of the cut-to-length machines in the simulator system with those provided by expert operators in the State of Oregon to determine the facial validity of forest harvest simulations in the John Deere harvesting simulator system. We considered whether the slope mobility and reach limits of the simulated machines are sufficiently similar to the expert defined limits to be educationally useful. Though the simulator has stability limits that are potentially greater than the real machine when operated by an expert operator, the findings indicated that the simulator is sufficiently similar to the real machines. Specifically, the 30% adverse, 40% favorable, and 15% side slope expert limits are considered facially valid for harvest plan development. Additionally, the expert operator in the simulator system operated between 4m to 11m away from the mast of the machine, supporting the conclusion that the forest harvest simulation is facially valid regarding reach and trail spacing.