Http://dx.doi.org/10.5902/1980509820659Esta pesquisa teve por objetivo realizar uma análise técnica e de custos dostratores florestaisfeller bunchereskidderna colheita de madeira dePinus taedaL. em diferentes produtividades do povoamento. O estudo foi conduzido em uma empresa florestal localizada na região Norte de Santa Catarina, Brasil. As análises foram realizadas por meio do estudo de tempos e movimentos, nos quais as operações de corte e extração foram subdividas em fases do ciclo de trabalho, determinando-se produtividade, eficiência operacional, consumo específico médio de energia e custos operacionais e de produção das máquinas em diferentes produtividades médias do povoamento (PMP): I (403,0 m3 ha-1); II (550,0 m3 ha-1) e III (670,0 m3 ha-1). Os resultados indicaram que o ciclo operacional doskidderfoi afetado pelas manobras adicionais nas operações de carga e descarga, ocasionado pelo baixo volume dos feixes de madeira sobre o terreno. O maior rendimento volumétrico do povoamento influenciou a produtividade e o custo de produção dofeller bunchereskidder, comprovando a importância dessa variável no planejamento das operações de colheita de madeira.

Brazilian forest companies today are experiencing difficulty with the lack of trained workers having the preferred requirements as machine operators. The aim of this study was to assess the ways in which behavioral profiles influenced the performance of the harvester operators during the operations, enabling managers to select suitable processes of the operators in future. This research was done in a forestry company in Midwest Brazil, using 20 harvester operators as a test sample. At first, a reference profile was developed for the harvester operators employing the behavioral profile tool. The operators were categorized into subgroups based on the features of their behavioral profiles. Operator performance was evaluated depending on their daily productivity during the operation over an 11-month period. Three operator subgroups, each having distinct behavioral profiles were identified. The learning curve revealed an increase in the production efficiency of the operators during the training period, and operators from profile classes 1 to 3 achieved their production targets in the 6th and 7th month from the training commencement, respectively. The productivity difference between the behavioral profiles of classes 1 and 3 was 6.7%, resulting in a monthly average variation in production of 1,180 m3 per machine.

Este trabalho teve por objetivo avaliar os potenciais ganhos de operadores de harvester no treinamento com uso de simuladores de realidade virtual. Foram coletados dados durante o treinamento de 39 operadores, avaliando-se os seus desempenhos nas variáveis: tempo de execução no corte da árvore, direção de queda, altura de corte, eficiência no processamento, eficiência no empilhamento e produtividade. Os resultados permitiram a conclusão de que o simulador de realidade virtual é uma ferramenta viável do ponto de vista técnico e essencial no apoio ao treinamento de operadores de máquinas florestais, possibilitando a obtenção de elevados ganhos de qualidade e produtividade. O melhor desempenho dos operadores ocorreu com a variável produtividade, cujo ganho médio foi de 41,3% em relação ao início do treinamento, seguido pelo tempo de execução, com 38,8%; e pela direção de queda, com ganho médio de 36,1%.

The great complexity of the operation of wood harvesting machines and unpredictable differences of performance between operators must be reflected in the industry recruitment techniques. This work aimed to carry out an evaluation of the bimanual motor skill in candidates for the position of harvester operators using a virtual reality simulator to generate information that can contribute to and improve the selection process. The work was developed at the Forest Operators Training Center (CENFOR), at the State University of the Center–West, in Irati, PR. A sample of 12 individuals was studied and distributed into three levels of performance. The motor ability of the individuals was evaluated through the variables: »run time«, »fall direction«, and »cutting height«, assessed at different points during a 4-hour practice – 0.5; 1.0; 1.5; 2.0; 3.0 and 4.0 hours – practice in a virtual harvester simulator. The data were analyzed by variance and means, as well as compared to a Tukey test at the 5% level of significance. The individuals had a significant difference in the variables »run time« and »cutting height«, and could be accurately used to predict bimanual motor skill/performance. There was a significant gain in the performance of the operators up to 1.5 hours after the beginning of the skill test, and all those who demonstrated greater and lesser ability in the first half hour of the test maintained this behavior until the end of the training period. The virtual reality simulator can be used as a tool to assess bimanual motor skills during the selection of harvester operators.

The objective of this study was to evaluate operators’ posture and repetitive motions in the mechanized wood harvesting operations, aiming comfort, safety, and health of forest operators. The study was carried out in the clearcutting of pine stands located in Paraná State, Brazil. Data were obtained in tree cutting operations with feller buncher and wood processing with harvesters, in which three operators in each machine were filmed during their workday. The typical postures were evaluated by Rapid Whole-Body Assessment (REBA) and Rapid Upper-Limb Assessment (RULA) methods, while repetitive motions were evaluated by Latko, Silverstein and Strain Index (SI) methods. The results showed the feller buncher operators remained long period seated in static position, with fists turning outside the neutral line and without pauses for recovery, although REBA and RULA methods had identified low postural risk. In wood processing operation, the spinal column and neck were the most affected body parts, presenting medium postural risk and the need for investigations and quickly changes by REBA and RULA methods, respectively. Besides that, wood harvesting operations with feller buncher and harvester were classified as high repeatability, showing more than 30 thousand repetitive motions in a workday, indicating high risk of Repetitive Strain Injuries (RSIs) and Musculoskeletal Disorders (MSDs) in the operators. Therefore, it is concluded the ergonomic measures are necessary to improve operators’ comfort and health.

The objective of this study was to evaluate the influence of different wheel types of a skidder on productivity and cost of Pinus taeda L. wood extraction. The study was conducted in a forestry company located in the municipality of Mandirituba, Paraná state, Brazil. The technical and cost analyses included a time and motion study of the wood extraction activity. The productivity, operative efficiency, energy consumption and the production and operational costs were determined for the machines with different wheel types: SDP - skidder with rubber tires; SD2 – skidder with tracks on the two front tires; and SD4 – skidder with tracks on the four tires. Results showed that the activity that demanded most time in the operational cycle was the maneuvering of the machines to pick up more than one tree, resulting in lost of productivity and need of improvement in the operational planning. The skidder equipped only with rubber tires showed higher productivity and lower production cost in the longest extraction distances, caused by the higher operating speed of the machine.Keywords: Timber extraction; wheel types; operating efficiency. ResumoInfluência dos rodados de um skidder na produtividade e no custo da extração florestal. Este trabalho objetivou avaliar a influência de diferentes tipos de rodados de um skidder na produtividade e no custo da extração de madeira de Pinus taeda L. O estudo foi conduzido em uma empresa florestal localizada no município de Mandirituba, estado do Paraná, Brasil. As análises técnica e de custo englobaram um estudo de tempos e movimentos da operação de extração florestal. Foi determinado a produtividade, eficiência operacional, rendimento energético e custos operacionais e de produção das máquinas equipadas com diferentes tipos de rodados: SDP – skidder com rodados de pneus; SD2 – skidder com pneus dianteiros recobertos com semiesteiras e SD4 – skidder com os quatro pneus recobertos com semiesteiras. Os resultados mostraram que a atividade que demandou o maior tempo do ciclo operacional foram as manobras realizadas pelas máquinas para apanhar mais de uma árvore, ocasionando perda de produtividade e necessidade de melhoria no planejamento operacional. O skidder equipado somente com rodados de pneus apresentou maior produtividade e menor custo de produção nas maiores distâncias de extração, ocasionado pela maior velocidade operacional da máquina.Palavras-chave: Extração florestal; tipos de rodados; eficiência operacional.