Coffee Science_v.17, 2022

URI permanente para esta coleção${dspace.url}/handle/123456789/13712

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    Determination of physical and mechanical properties of the coffee branch: an experimental approach
    (Universidade Federal de Lavras, 2022-06-09) Melo Júnior, Wellington Washington Andrade de; Santos, Fabio Lúcio; Scinocca, Francisco; Rosa, Pablo Antunes da; Magalhães, Ricardo Rodrigues
    In order to reduce the human efforts during manual harvesting and increase the operational capacity and quality, the mechanization of the harvesting operation has been significantly increasing in the last few years for coffee crops. Therefore, for the design of coffee harvesting machines, the physical and mechanical properties of coffee branches are of utmost importance for harvesting machines projects. In this way, using an experimental approach, the present paper analyzes the variability of physical and mechanical properties in the coffee branches, of the Coffea arabica L., cultivar Catuaí-Vermelho (IAC 144). The branches were collected in different positions, along the orthotropic branch: upper, middle and lower parts of the plant. The mass, volume, spe-cific mass, and modulus of elasticity of the collected specimens were determined considering their position in the plant and position along the branches. According to the position in the plant, no significant differences were found between the specific mass averages for the upper, middle, and lower parts of the plant. The research obtained an average of 1.24 GPa with a standard deviation of 0.13 GPa for the elasticity modulus. A significant increase in the elasticity modulus could be noted in the branches from the top to the bottom of the plant in the present research.
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    Effect of flight operative height and genotypes on conilon coffee spraying using an unmanned aerial vehicle
    (Universidade Federal de Lavras, 2022-06-09) Vitória, Edney Leandro da; Oliveira, Ronaldo Furtado de; Crause, Deborah Hoffmam; Ribeiro, Luis Felipe Oliveira
    This study analyzed the effect of operational flight height and conilon coffee genotypes in the deposition and uniformity of destruction in the plant’s can-opy. The spray were conducted using a unmanned aerial vehicle in a conilon coffee plantation. The experiment was carried out with a randomized block design and treatments arranged in a factorial scheme, with three operational flight heights in relation to the coffee canopy and three genotypes of conilon coffee (Coffea canephora). The parameters evaluated were volume median diameter (VMD), density of drops and coverage (%). The interaction between flight height variables and canopy’s range was significant for the data on VMD variables, droplet density and coverage. According to the results, spray performance at an average height of 3.0 m is better than at 2.0 and 4.0 m. At 4.0 m, we observed a decrease in these variables, and this can be explained by a possible drift caused by the wind intensity and direction at higher heights. The coverage on the genotype A1 leaves was higher when compared to the other genotypes, although flight operational height was significantly different only in this genotype, 8.1% at 4.0 m, we observed at this height the lowest coverage values.