Biblioteca do Café
URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/1
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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 Mapeamento automatizado de áreas de café em Minas Gerais(Embrapa Café, 2021-09) Alves, Helena Maria Ramos; Volpato, Margarete Marin Lordelo; Campos, Beatriz Fonseca DominikItem Caracterização dinâmica da planta do cafeeiro visando a colheita mecanizada por vibrações mecânicas(Universidade Federal de Lavras, 2023-07-28) Pereira, Mariana Ribeiro; Santos, Fábio Lúcio; Navarro, Hector Andres Tinoco; Villibor, Geice PaulaA colheita mecanizada do café tem sido realizada de forma eficiente por meio do princípio de vibrações mecânicas, sendo afetada por fatores relacionados à máquina e à planta, tornando-se necessário o conhecimento de suas propriedades modais. Neste contexto, este trabalho foi desenvolvido com o intuito de caracterizar o comportamento dinâmico das plantas de café visando a determinação de suas propriedades modais em condições de campo, considerando cargas pendentes de frutos em diferentes estádios de maturação. Para isso, foi realizado a instrumentação de quinze plantas escolhidas ao acaso, para a coleta dos dados de campo avaliando-se diferentes cenários. A partir de ensaios de análise modal experimental, foi possível observar que houve maior incidência de picos de frequências naturais concentrando-se entre 20 e 40 Hz. Os valores das razões de amortecimento dos ramos plagiotrópicos das plantas de café com frutos predominantemente maduros, relativas aos terços superiores, médios e inferiores, foram 0,145, 0,134 e 0,127, respectivamente. Por meio da indução de vibrações mecânicas, foi possível determinar os valores de transmissibilidade de vibração das plantas do café, em que a frequência de 20 Hz apresentou maior transmissibilidade de vibração em relação as demais frequências induzidas. Por fim, a partir de ensaios de varredura de frequências foi possível avaliar o comportamento dinâmico das plantas de café, os quais mostraram que houve uma maior incidência de picos de frequências naturais concentrando-se acima de 40 Hz. A partir deste estudo, observou-se que a colheita seletiva dos frutos de café mediante aplicação exclusiva de vibração torna-se inviável, já que não houveram diferenças significativas para as cargas pendentes de frutos em diferentes estádios de maturação e também devido a sobreposição de valores de frequências observados nas faixas de frequência estudadas.Item Remotely piloted aircraft and computer vision applied to coffee growing management(Universidade Federal de Lavras, 2022-11-25) Santana, Lucas Santos; Ferraz, Gabriel Araújo e SilvaDigital and precision agriculture technologies used in coffee farming have gained space and have become necessary in many coffee production stages. Among the emerging technologies, the Remotely Piloted Aircraft (RPA) can be highlighted because their products can be used as data providers for machine learning techniques and automated monitoring forms. This study aimed to apply cartographic and photogrammetric products from RPAs submitted to machine learning techniques and image analysis in digital and precision coffee farming. Three types of research were built: Application of RPA cartographic products for the coffee plant implantation project; Identification and counting of plants in PRA images and Investigations of plants development in renewal areas. (I)The first study evaluated different flight mission composition efficiency and point cloud levels for Digital Terrain Models generation applied in coffee plantations. Flights performed at 120 m Above Ground Land (AGL) and 80 × 80% overlap showed higher assertiveness and efficiency. The 90 m AGL flight showed great terrain detail, causing significant surface differences concerning the topography obtained by Global Navigation Satellite System (GNSS) receivers. Slope ranges up to 20% are considered reliable for precision coffee growing projects. Changes in flight settings and image processing are satisfactory for precision coffee projects. Image overlap reduction significantly lowed the processing time without influencing Digital Terrain Model DTM's quality. (II) The second research aimed to develop an algorithm for automatic counting coffee plants and define the plant's best age to carry the monitoring using RPA images. Plants with four months of development showed 86.5% count assertiveness. The best results were observed in plantations with six months of development, presenting an average of 96.8% of assertiveness in automatically counting plants. This analysis enables an algorithm development for automated counting of coffee plants through RGB images obtained by remotely piloted aircraft and machine learning applications. (III) The objective of the third research was to monitor the coffee plants' development planted on ash from crop residues through vegetative indices in RPA images, analysis of chemical elements presents in the ash and soil analysis. Preliminary results indicate the high presence of aluminum and potassium in the ash, causing significant differences in coffee development beginning. In addition, variations were observed in vegetative indices values in regions with ash presence, highlighting the NGI and NNIRI indices. The research developed by this paper provides essential information for digital agriculture technologies advancement in coffee growing.
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