Ergonomic device to harvest Castilla-Blackberry

Agriculture is one of the major economic activities in Colombia, counting for almost 47% of all country exportations. Considering Santander province, Castilla-Blackberry is one the most common agro-alimentary crops in the area (northeastern region of the country), but this particular cultivar presents thorns that rend harvesting difficult and increase the risk for skin or subcutaneous injuries. Other important issues of the harvesting processes are related to a rapid deterioration of the picking gloves, the homogeneous distribution of the fruit throughout the bush and the transportation of the harvested fruits during this activity (total load can be as high as 13 kg). In addition, the pinch gesture used to pick the fruit and the low back strain due to the heavy loads are responsible for hand pain and low back pain in this workers population. This work presents an experimental validation and a theoretical evaluation of a new ergonomic device to harvest Castilla-Blackberry, through a direct comparison with the traditional harvesting method. This new tool looks forward to reducing loads on the low back and to avoid cutaneous cuts. The experimental validation involved seven subjects in a real crop environment. Each participant, picked blackberry fruits in the morning hours, using both traditional elements and the new harvesting device. Meanwhile, posture data (articular angles variation) and hand cuts (gloves wear) were recorded. The new device supports up to 13 kg with a transfer system that reduces the intradiscal load in about 85.13%. Likewise, the pinch gesture was substituted with a supínate natural-hand closing gesture without detriment of the number of harvested fruits. Statistical analysis of trunk flexion does not evidence significant differences between both methods (p-value = 0.92), however, it was found a reduction in trunk flexion when the new device is used on sloping grounds. On the other hand, gloves wear analysis showed a decrease on the number of cuts and the washable materials used in the new device lead to a reduction of the annual use of new gloves in about 96.16%. In conclusion, the new device improves blackberry harvesting when biomechanical and physical risks are considered. Hence, it could be a viable alternative to be implemented in close collaboration with the concerned community, ensuring its appropriation of knowledge and promoting better labor conditions.