Optimization in the distribution and sequencing of machines in wood harvesting in planted forests

Aim of study: The objective was to evaluate an optimized model for the distribution and sequencing of machines in tree felling and processing and extraction operations, aiming to reduce unproductive times and gains in production capacity. Area of study: The study was conducted in a cellulose and paper company in the state of Parana, Brazil, in operational areas of the wood harvesting. Material and methods: The times of tree felling, processing and extraction were obtained from a harvester (hv) and a forwarder (fw) to estimate the operational efficiency and productivity of the system. At the same time, vector features equivalent to the set of plots in the area, roads and a matrix feature of the digital terrain model were obtained from a geographic database for estimation of a matrix of distances between the plots. The Ward method of hierarchical grouping was used based on the matrix of distances between the fields to form two work groups (GI and GII). For each working group, the shortest walking sequence was estimated using the Kruskal algorithm. Main results: An optimized distribution of 3 hw and 2 fw was necessary in GI to achieve the production target of 200 m³ PMH-1, with the machines covering a distance of 2,335 m. The proportion of machines 3 hw and 3 fw was needed in GII with a distance covered of 2,878 m. The proposed model optimized the number of machines and provided a 26.7% reduction in the total displacement of machines. Research highlights: The high cost of wood harvesting operations requires the use optimized of the forestry machines. The proposed model made it determine with efficiency the machines distribution and sequencing for a wood harvesting optimized. The model can be implemented in the operational planning in the forestry companies in more complex wood harvesting scenarios.