Assessing the Utility of Two Integrated Harvester-Forwarder Machine Concepts Through Stand-Level Simulation
Authors
B. Talbot
The Danish Centre for Forest, Landscape and Planning
T. Nordfjell
Swedish University of Agricultural Sciences
K. Suadicani
The Danish Centre for Forest, Landscape and Planning
Abstract
The relative performance of two integrated machine concepts (combined harvesting / forwarding capabilities) was assessed against a conventional harvester / forwarder CTL system in a simulated thinning regime. Multiple-regression based on the simulation output was used in deriving time-consumption functions at the systems and machine level. Descriptive stand variables could be reduced to; harvest volume (m3/ha), stem volume (m3), lead distance (m) and object volume (m3/ stand) while maintaining acceptable statistical rigour (R2 > 0.95). The ability of one of the integrated machines to process logs directly onto the bunk provided it with an advantage that more than compensated for its reduced harvesting efficiency. Both integrated machine systems show a competitive advantage in forest structures with low object volumes and long or frequent relocations.
Factors negatively affecting forwarding productivity (e.g. long lead distances) favour the conventional two-machine system. A break-even economic analysis showed that integrated machines could present a feasible alternative to contemporary mechanised CTL systems.
