RESUMO O direcionamento automático de máquinas agrícolas via sinal GNSS (Global Navigation Satellite System) tem sido adotado cada vez mais pela comunidade agrícola na última década. Produtores de amendoim estão adotando tal tecnologia a fim de melhorar o paralelismo das operações face às dificuldades principalmente encontradas no arranquio mecanizado, onde as perdas são, todavia, um grande problema. Objetivou-se avaliar as operações mecanizadas de semeadura e de arranquio de amendoim controlados manualmente e com piloto automático, juntamente com a qualidade das operações. Os tratamentos consistiram de duas operações de escavação, com e sem piloto automático, e duas velocidades de deslocamento (4,5 e 6,0 km h-1). O experimento foi realizado em solo de textura média, sob delineamento inteiramente casualizado disposto em faixas, utilizando-se das variáveis analisadas como indicadores de qualidade. Na semeadura foi avaliado o paralelismo entre as passadas do conjunto trator-semeadora em 120 pontos de cada sistema (direcionamento manual e automático). Foram avaliadas as perdas de arranquio nos dois sistemas de direcionamento sob duas velocidades de deslocamento (4,5 e 6,0 km h-1), em 15 pontos de cada tratamento. Verificou-se que o paralelismo entre as passadas do conjunto trator-semeadora foi melhor quando se utilizou do piloto automático, além da maior qualidade da operação. A velocidade de deslocamento não influenciou as perdas de arranquio. Não houve diferenças nas perdas visíveis de arranquio, porém quando o arranquio foi realizado com o piloto automático obteve-se maior qualidade. Menores perdas invisíveis e totais de arranquio foram obtidas quando o arranquio foi realizado com o direcionamento automático, e qualidade superior foi obtida na velocidade de 4,5 km h-1; porém, a qualidade foi afetada negativamente sob operação manual. Portanto, o uso do piloto automático se mostrou eficaz na melhoria da precisão e da qualidade das operações.

ABSTRACT Over the past decade, automatic guidance of agricultural machinery via Global Navigation Satellite System (GNSS) signals has been increasingly adopted by the farming community. Peanut farmers are adopting such technology in order to improve the parallelism of operations to address difficulties that occur in mechanical digging, where losses are a big problem. This study aimed to evaluate mechanized operations of peanut sowing and digging controlled manually and by autopilot, along with their quality. The treatments consisted of two digging operations, with and without autopilot, and two displacement speeds (4.5 and 6.0 km h-1). The experiment was conducted in a medium-textured soil in a completely randomized design arranged in bands, using the analyzed variables as quality indicators. At sowing, parallelism between passes of the tractor-sower set, was evaluated at 120 points of each system (manual and automatic routing). The digging losses were evaluated in the two guidance systems, under two displacement speeds (4.5 to 6.0 km h-1) at 15 points per treatment. It was verified that the parallelism between the passes of the tractor-sower set was better when using the autopilot, which improved the operation quality. Displacement speed did not influence the digging loss. There were no differences in the visible digging loss, but higher quality was obtained when the operation was performed using autopilot. Minor invisible and total digging losses were obtained when the digging was performed with automatic routing, and superior quality was found at a speed of 4.5 km h-1; however, quality was adversely affected under manual operation. Thus, the use of autopilot is effective for improving the accuracy and the quality of the operations.

ABSTRACT: The intensive mechanization during the harvest operation and success of this operation depends on several factors, one of which is the length and format of the plots. The aim of this study was to evaluate the operating performance of a soybean harvester in different geometric plots shape, using as quality indicators performance parameters by means of statistical control tools of process. The experiment was conducted in March 2014 in the city of Uberaba - MG. Operational capacity was evaluated in the mechanical harvesting of soybeans in three plots: irregular, rectangular and trapezoidal. Performance evaluations of soybean harvester were made from the following parameters: displacement speed, engine rotation, cylinder rotation and concave opening. The grain water contents affect the quality indicators of the soybean harvester performance in all plots shapes. The harvester performance is considered able to maintain between the specification limits and close to the target, to speed quality indicators the irregular and the trapezoidal plots and for cylinder rotation the trapezoidal plot.

ABSTRACT: Information on harvester performance is important in the management and optimization of mechanized agricultural systems. In this sense, the aim of this study was to monitor the operation quality of soybean mechanical harvesting in different plot shapes by means of statistical process control. The harvest was carried out in an agricultural area of a farm located in Uberaba, MG, Brazil, with an experimental design based on the assumptions of statistical quality control and 18, 28, and 24 replications for irregular, rectangular, and trapezoidal plots, respectively. The variables and/or quality indicators of harvester performance were forward speed, engine speed, cylinder speed, and concave opening. The lowest variation occurred in the irregular plot for the quality indicators forward speed and engine speed of harvester. Engine speed and the concave opening of harvester were unstable for all plot shapes. Only the cylinder speed of the soybean harvester presented process stability during operation for the three plot shapes.

ABSTRACT: The mechanized gathering process of sweeping coffee is extremely important to reduce the losses of fruit not used in the harvesting operation. But this operation usually has a low operational performance and a high cost per unit collected in this way any measures that can effectively reduce costs increase the viability of the operation. In this sense, studies on adequacy tractor mass for each operation show improvement in energy use, reducing fuel consumption. So, this study aimed to quantify the fuel consumption and effective power along the process of a tractor 4x2 FWD pulling the coffee harvester. I was used as treatments three ballasting settings, these being equivalent the relations power to weight of 36, 39 and 42 kg hp-1 working with and without activated FWD, randomized statistically, with 10 repetitions each configuration. It was conclude that, at low power-weight ratio, the front wheel drive assist had no significant influence on the hour fuel consumption. Already in the configuration with higher ratio, the use of front wheel drive favored in reducing fuel consumption and better energy use.

RESUMO O controle estatístico de processo aplicado em operações agrícolas mecanizadas representa uma nova maneira de avaliar a qualidade com que as operações são realizadas. Neste sentido, objetivou-se neste trabalho comparar três tipos de ferramentas do controle estatístico de processo aplicadas às perdas na colheita mecanizada de cana-de-açúcar, para determinar qual o melhor modelo de carta de controle a ser utilizado para este indicador de qualidade. O monitoramento das perdas na colheita mecanizada foi realizado diariamente nas áreas agrícolas, de uma unidade produtora na região do Triângulo Mineiro - MG, durante o período de 70 dias, na safra de 2014. Ao final do período de avaliação, foram coletados 194 pontos amostrais no total, para cada tipo de perda analisado. As cartas de controle utilizadas foram: carta de valores individuais, média móvel e média móvel exponencialmente ponderada. Os indicadores de qualidade avaliados durante a colheita de cana-de-açúcar foram as perdas do tipo: rebolo inteiro, tocos, pedaço fixo, cana inteira, lascas, pedaços soltos e totais. A carta de controle de valores individuais é a melhor opção para o monitoramento das perdas na colheita mecanizada de cana-de-açúcar, por apresentar maior facilidade na interpretação dos resultados, em relação às demais.

ABSTRACT Statistical process control in mechanized farming is a new way to assess operation quality. In this sense, we aimed to compare three statistical process control tools applied to losses in sugarcane mechanical harvesting to determine the best control chart template for this quality indicator. Losses were daily monitored in farms located within Triângulo Mineiro region, in Minas Gerais state, Brazil. They were carried over a period of 70 days in the 2014 harvest. At the end of the evaluation period, 194 samples were collected in total for each type of loss. The control charts used were individual values chart, moving average and exponentially weighted moving average. The quality indicators assessed during sugarcane harvest were the following loss types: full grinding wheel, stumps, fixed piece, whole cane, chips, loose piece and total losses. The control chart of individual values is the best option for monitoring losses in sugarcane mechanical harvesting, as it is of easier result interpretation, in comparison to the others.