ABSTRACT Timber harvest operations in a Pinus taeda thinning require a few different postures by machine operators that could be harmful to their health. This research aimed to analyze the upper limb posture of the operators in two harvester models, a tracked versus wheeled harvester in thinning of Pinus taeda stands, to identify possible issues and propose ergonomic solutions. The postural analysis was conducted in thinning operations, by filming the operators at their workstations. Posture evaluations were performed by the Rapid Upper-Limb Assessment (RULA) and Rapid Entire Body Assessment (REBA) methods and analyzed the outcomes by factorial analysis. Results showed that the operators stayed for a long time in the static sitting posture and with operational repetitive movements, worsened by the absence of recovery work breaks, with significant statistical differences for the two machines evaluated. For the tracked harvester, 15 typical postures were identified, and in 91% and 92% of the workday, the operator had their trunk and head inclined, respectively. For the wheeled harvester, only eight typical postures were identified, and in 12% and 50% of the time, the operatorremained with their trunk and head tilted. Finally, we were able to observe that tracked harvester operators spent more time on postures ergonomically harmful, with higher action level measures needed. The wheeled harvester provided the best working conditions in terms of posture and repetitiveness, making it the most ergonomically suitable machine.

中文翻译：

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履带式与轮式收割机在松树间伐时的上肢姿势和运动

摘要 火炬松间伐中的木材采伐操作需要机器操作员采取一些可能对他们的健康有害的不同姿势。本研究旨在分析两种收割机模型中操作员的上肢姿势，履带式和轮式收割机对火炬松林分进行间伐，以确定可能出现的问题并提出符合人体工程学的解决方案。姿势分析是在减薄操作中通过拍摄操作员在他们的工作站上进行的。通过快速上肢评估 (RULA) 和快速全身评估 (REBA) 方法进行姿势评估，并通过因子分析分析结果。结果表明，操作员长时间保持静态坐姿和重复操作动作，由于没有恢复工作休息而恶化，评估的两台机器具有显着的统计差异。对于履带式收割机，确定了 15 种典型姿势，并且在 91% 和 92% 的工作日中，操作员的躯干和头部分别倾斜。对于轮式收割机，仅识别出 8 种典型姿势，并且在 12% 和 50% 的时间内，操作员保持躯干和头部倾斜。最后，我们能够观察到履带式收割机操作员花费更多时间在对人体工程学有害的姿势上，需要采取更高的行动水平措施。轮式收割机在姿势和重复性方面提供了最佳的工作条件，使其成为最符合人体工程学的机器。操作员的躯干和头部分别倾斜。对于轮式收割机，仅识别出 8 种典型姿势，并且在 12% 和 50% 的时间内，操作员保持躯干和头部倾斜。最后，我们能够观察到履带式收割机操作员花费更多时间在对人体工程学有害的姿势上，需要采取更高的行动水平措施。轮式收割机在姿势和重复性方面提供了最佳的工作条件，使其成为最符合人体工程学的机器。操作员的躯干和头部分别倾斜。对于轮式收割机，仅识别出 8 种典型姿势，并且在 12% 和 50% 的时间内，操作员保持躯干和头部倾斜。最后，我们能够观察到履带式收割机操作员花费更多时间在对人体工程学有害的姿势上，需要采取更高的行动水平措施。轮式收割机在姿势和重复性方面提供了最佳的工作条件，使其成为最符合人体工程学的机器。我们能够观察到，履带式收割机操作员花费更多时间在对人体工程学有害的姿势上，需要采取更高的行动水平措施。轮式收割机在姿势和重复性方面提供了最佳的工作条件，使其成为最符合人体工程学的机器。我们能够观察到，履带式收割机操作员花费更多时间在对人体工程学有害的姿势上，需要采取更高的行动水平措施。轮式收割机在姿势和重复性方面提供了最佳的工作条件，使其成为最符合人体工程学的机器。