Ergonomic evaluation of hand tools used in grape pruning activities in vineyards

Abstract: Grape farming is a labour-intensive operation, with pruning as one of the tasks performed with hand tools. Most of the tropical countries use locally made and commercially available hand pruning tools for grape pruning. Different pruning tools were selected for ergonomic evaluation and refinement was completed based on the physiological responses of the subjects. The comparison between the commercially available Economy tool (M₂), Maharashtra tool (L₁) and Karnataka tool (L₂) model pruner shows that the model Economy tool (M₂) gives better performance. Economy tool (M₂) model is highly preferred by the grape farmers due to its high performance and more comfort than Maharashtra tool (L₁) and Karnataka tool (L₂) pruner. This is due to standard material, shape of the pruner slightly bent for easy handling. In Maharashtra (L₁) and Karnataka pruning tool (L₂) due to direct pressure or “contact stress” refers to on-going contact between a part of the body and a hard edge or surface which in cause the discomfort and pain. Similarly, pressure points of any type can interfere with production. The physiological responses were measured and compared between the ergo refined pruning tool (EM₃) and other selected pruning tools. The results for the Ergo refined pruning tool (EM₃) registered are 95.2 beats min^-1 (Heart rate), 0.566 l min^-1 (Oxygen consumption), 11.81 KJ min^-1 (Energy expenditure), 30.31 and 20.8 percent of AWL and LCP which is lower values when compared to other selected pruning tools. It was also observed that cutting frequency and area coverage for selected pruning tool varies from 11 to 24 cuts/ min and 750 to 1350 m²/ h. Ergo refined pruning tool (EM₃) registered 24 cuts/ min and 1350 m²/ h when compared with other pruning tools. A full hand loop was fitted below the lower handle to improve grip and uniformly apply force throughout the pruning operation, resulting in increased area coverage and frequency of cut.