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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Resultados da Pesquisa
Item Vibration Transmissibility of the Coffee Fruit-Peduncle System: a Forced Vibration Study of High Frequency Aiming Mechanical Harvesting(Associação Brasileira de Engenharia Agrícola, 2023-01-30) Villibor, Geice P.; Santos, Fábio L.; Queiroz, Daniel M.; Khoury Junior, Joseph K; Pinto, Francisco A. C.Semi-mechanized and mechanized harvesting use machines that promote the transference of vibrational energy and impact to achieve the detachment of coffee fruits. The aim of this study was to evaluate the vibration transmissibility in coffee fruit-peduncle systems, using high-speed cameras, submitted to high frequency harmonic excitation in different combinations between frequency and amplitude of vibration, identifying working ranges suitable to perform selective harvesting. Vibration transmissibility was determined for the coffee fruit-peduncle systems, for the maturation stages unripe and ripe that were subjected to a sinusoidal harmonic displacement, in which the input parameters were frequency (35, 45 and 55 Hz) and peak-to-peak amplitude (3.5, 5.0 and 6.5 mm). An experiment was used to study the effect of frequency and amplitude on vibration transmissibility in a completely randomized design in a factorial scheme 3 x 3 x 2, with three replications. The frequency of 35 Hz, associated with the amplitudes 3.5-6.5 mm, was the one that most influenced the results of vibration transmissibility. For the frequency of 55 Hz and amplitude of 6.5 mm, in the ripe maturation stage, the vibration transmissibility was higher than 1.0, which could be a suitable combination for selective coffee harvesting.Item Mobile Application for Adjusting Air-Bast Sprayers in Coffee Plantation(Associação Brasileira de Engenharia Agrícola, 2022-09-13) Cunha, João P. A. R. da; Alves, Thales C.; Penha, Rafael S. A.Mobile application development advances, particularly for smartphones and tablets, have allowed farmers to make decisions more assertively in their agrobusiness management. This article addresses the development and evaluation of an app aimed at people who deal with the pesticide application technology in coffee farming, more specifically, adjustment and calibration of sprayers. This mobile app provides the main data necessary for a correct calibration of air-blast sprayers to apply pesticides in coffee planting. Its functionalities include calculation of the application rate for each situation (L ha-1) based on data obtained in the field, such as canopy volume. The app, called SprayCafé, was developed for the Android platform using the Java programming language in the integrated development environment Android Studio. After the development, the application was evaluated, based on a questionnaire answered by 139 users, who ranked the following requirements: ease of use, loading time, adequacy of screen resolution, data relevance, sequence of information, and applicability, among others. The system proved to be simple and robust; it was thus assessed as adequate to the field and to be of great value for coffee planting, especially because it allows safer and more adequate pesticide application. The graphical user interface is interactive and easy to use.Item Spatial variability of noise generated by a self-propelled coffee harvester in an open area(Associação Brasileira de Engenharia Agrícola, 2022-07-31) Silva, José A. R. da; Manzione, Rodrigo L.; Oliveira Junior, Geraldo G. de; Silva, Adriano B. da; Putti, Fernando F.Despite the advantages in production, mechanization may expose workers to high noise levels in the work environment, which is considered one of the main causes of work-related hearing loss. In this sense, this study aimed to analyze the spatial variability of noise generated by a self-propelled coffee harvester in an open area to define safe zones for operators and workers involved in coffee harvesting activities. The noise source used was an Electron Auto TDI self-propelled coffee harvester (model MWM D229-4), with a cabin manufactured in 2012 and a 67-hp 4-cylinder engine, working at 1200-rpm rotation. The noise level was measured by a digital decibel meter at points distributed within a regular 2.5 x 2.5 m sampling mesh (32.5 x 35.0 m area) surrounding the harvester in operation, which was configured according to the regulatory standard. Noise level spatial dependence was analyzed through geostatistics, characterizing structure and magnitude, and mapping spatial variability. Results showed that noise levels were above the limit established by relevant legislation (i.e., 85 dB), both for operators and employees at a distance of about 5.5 m from the generating source.Item Octave band sound pressure level emitted by agricultural implements in coffee plantations(Universidade Federal de Santa Maria, 2024-02-23) Anderson, Carlos Guida; Sabino, Paulo Henrique de Siqueira; Oliveira Júnior, Geraldo Gomes de; Silva, Gian Otávio Alves daIn Brazil, certain studies have been performed on the exposure to global occupational noise levels when mechanized equipment is used in coffee-growing. However, these did not indicate the behavior within a frequency spectrum (Hz) by octave bands. The objective of this study was to assess the sound pressure levels of the brush, mower, and atomizer attached to a tractor under actual operating conditions by using 1/1 octave band filters. Quantitative assessments were performed with the mower, brush, and atomizer attached to the MF 275 tractor under two conditions: operative and static. The noise levels obtained under actual operating conditions were determined using a DOS 1000 noise dosimeter and an octave band filter. The static condition assessments were performed inside and outside the coffee plantation using a Hikari HDB 900 digital sound level meter. The NR 15 and NHO 01 standards were used to analyze the data. Under operative and static conditions, the tractor units showed noise levels above the exposure limit of 85 dB (A) for an 8h working day. The assessment of the frequency spectrum revealed the highest noise levels to be in the 125-1000 Hz range.Item Maturation and detachment force for mechanized harvesting of irrigated Conilon coffee in the Brazilian Cerrado(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2023-02-17) Santin, Mateus Rollemberg; Amabile, Renato Fernando; Malaquias, Juaci Vitória; Veiga, Adriano Delly; Brige, Felipe Augusto Alves; Sala, Pedro Ivo Aquino LeiteThe objective of this work was to determine the force required to detach fruits of Conilon coffee (Coffea canephora) genotypes in five maturation stages, to determinate the best stage for mechanized harvest, and to verify the possibility of future selections of genotypes adapted to mechanized harvesting. Harvests were carried out in the 2013/2014 crop season, and the detachment force was determined based for six fruits from each side of the crop row, collected randomly from the middle third of the plants. The detachment force curve was obtained for each cycle through logistic regression, using the R software. According to the duration of their cycle, the genotypes were divided into super early, early, medium, and semilate; the values of the coefficients of the detachment force curve equation were also obtained. There is genetic variability regarding fruit detachment force throughout the maturation cycle, which indicates the possibility of selecting genotypes adapted to mechanized harvesting. Fruit detachment force shows a considerable drop in the final stages of maturation. The raisin stage is the best for the mechanized harvest of irrigated Conilon coffee in the Cerrado.Item Mobile application for adjusting air-blast sprayers in coffee plantation(Associação Brasileira de Engenharia Agrícola, 2022-09-13) Cunha, João P. A. R. da; Alves, Thales C.; Penha, Rafael S. A.Mobile application development advances, particularly for smartphones and tablets, have allowed farmers to make decisions more assertively in their agrobusiness management. This article addresses the development and evaluation of an app aimed at people who deal with the pesticide application technology in coffee farming, more specifically, adjustment and calibration of sprayers. This mobile app provides the main data necessary for a correct calibration of air-blast sprayers to apply pesticides in coffee planting. Its functionalities include calculation of the application rate for each situation (L ha-1) based on data obtained in the field, such as canopy volume. The app, called SprayCafé, was developed for the Android platform using the Java programming language in the integrated development environment Android Studio. After the development, the application was evaluated, based on a questionnaire answered by 139 users, who ranked the following requirements: ease of use, loading time, adequacy of screen resolution, data relevance, sequence of information, and applicability, among others. The system proved to be simple and robust; it was thus assessed as adequate to the field and to be of great value for coffee planting, especially because it allows safer and more adequate pesticide application. The graphical user interface is interactive and easy to use.Item Photovoltaic plant to supply energy for an electric coffee dryer - energy costs and compensation(Associação Brasileira de Engenharia Agrícola, 2023-11) Konopatzki, Evandro A.; Oliveira, Cristiane L. de; Marangoni, Filipe; Edwiges, Thiago; Christ, DivairIn this work, we sought to minimize electricity costs in the coffee bean drying process by carrying out the theoretical sizing of the economic viability of the Photovoltaic Power plant (PVP) ongrid used to supply a Dryer Unit (DU). The methodology consisted of adequate sizing of a PVP generation plant to promote the electric energy balance. It used economic indicators such as internal rate of return, discounted payback, and net present value. Two scenarios were considered: a pessimistic with DU use on-peak period; and an optimistic with full use of the DU during the off-peak period. It was considered local electricity tariff values, and the results indicated the economic feasibility for the PVP installation also the feasibility of the dryer use in both scenarios, there are no restrictions on operating hours. It can be concluded that it is essential to understand the Brazilian electricity bill legislation because only in this way is it possible to properly develop the on-grid photovoltaic power plant projects. The technical and economic parameters are inseparable and indicated that the electricity tariff should not exceed US$ 0.22 (kWh) -1 to ensure the photovoltaic power plants installation viability to supply DUs that remain in operation during on-peak periods.Item 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 RodriguesIn 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.Item 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 OliveiraThis 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.Item Detection of coffee fruits on tree branches using computer vision(Escola Superior de Agricultura "Luiz de Queiroz", 2022-09-12) Bazame, Helizani Couto; Molin, José Paulo; Althoff, Daniel; Martello, MaurícioCoffee farmers do not have efficient tools to have sufficient and reliable information on the maturation stage of coffee fruits before harvest. In this study, we propose a computer vision system to detect and classify the Coffea arabica (L.) on tree branches in three classes: unripe (green), ripe (cherry), and overripe (dry). Based on deep learning algorithms, the computer vision model YOLO (You Only Look Once), was trained on 387 images taken from coffee branches using a smartphone. The YOLOv3 and YOLOv4, and their smaller versions (tiny), were assessed for fruit detection. The YOLOv4 and YOLOv4-tiny showed better performance when compared to YOLOv3, especially when smaller network sizes are considered. The mean average precision (mAP) for a network size of 800 × 800 pixels was equal to 81 %, 79 %, 78 %, and 77 % for YOLOv4, YOLOv4-tiny, YOLOv3, and YOLOv3-tiny, respectively. Despite the similar performance, the YOLOv4 feature extractor was more robust when images had greater object densities and for the detection of unripe fruits, which are generally more difficult to detect due to the color similarity to leaves in the background, partial occlusion by leaves and fruits, and lighting effects. This study shows the potential of computer vision systems based on deep learning to guide the decision-making of coffee farmers in more objective ways.