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Macaw (Acrocomia aculeata) is a product of Brazilian socio-biodiversity and is an excellent source of oil for the cosmetics, food and fuel industry. One of the technical bottlenecks of macaw fruit production is the manual harvesting with rudimentary tools and the extractive system, which has a very large dependence on labor. The objective of this work was to develop the informational and conceptual design of a semi-mechanized harvesting system that can be used in adverse conditions of relief, also directed to the needs of family farmers. In this work the concept of a low cost macaw harvester is proposed, which works by the principle of mechanical vibrations, and is able to work efficiently in planted and natural plantations. From an adaptation of the Pahl and Beitz method for the development of machine designs, and the use of the evolution prototyping method, integration prototypes were constructed, which underwent a preliminary field test. Some modifications were made in portable coffee breakers, which constituted changes in the vibration signal generation system that were transmitted to macaw fruits at the head / plant interface. Only one of the built prototypes was considered effective and suitable for subsequent performance (product under patent registration). For the detailed design, CAD (Computer Aided Design) techniques were employed. Later, it was possible to observe the validation of efficiency of the macaw fruit harvest by the principle of mechanical vibrations. Under field conditions, field trials demonstrated that the average harvest efficiency for the proposed model with vibrating rods was 97.4% and the average harvesting capacity was 566.91 kg h-1.

Design of an agricultural machine is a highly complex process due to interactions between the operator, machine, and environment. Mountain coffee plantations constitute an economic sector that requires huge investments for the development of agricultural machinery to improve the harvesting and post-harvesting processes and to overcome the scarcity of work forces in the fields. The aim of this study was to develop a preliminary design for a virtual prototype of a coffee fruit harvester. In this study, a project methodology was applied and adapted for the development of the following steps: project planning, informational design, conceptual design, and preliminary design. The construction of a morphological matrix made it possible to obtain a list of different mechanisms with specific functions. The union between these mechanisms resulted in variants, which were weighed to attribute scores for each selected criterion. From each designated proposal, two variants with the best scores were selected and this permitted the preparation of the preliminary design of both variants. The archetype was divided in two parts, namely the hydraulically articulated arms and the harvesting system that consisted of the vibration mechanism and the detachment mechanism. The proposed innovation involves the use of parallel rods, which were fixed in a plane and rectangular metal sheet. In this step, dimensions including a maximum length of 4.7 m, a minimum length of 3.3 m, and a total height of 2.15 m were identified based on the functioning of the harvester in relation to the coupling point of the tractor.

A macaúba (Acrocomia aculeata) é um produto da sociobiodiversidade brasileira e é uma excelente fonte de óleo para a indústria cosmética, de alimentos e de combustíveis. Um dos gargalos técnicos da produção dos frutos da macaúba é a colheita feita de forma manual com ferramentas rudimentares e no sistema extrativista, que tem dependência muito grande de mão de obra. Objetivou-se com o presente trabalho desenvolver o projeto informacional, conceitual e detalhado de um sistema semi-mecanizado de colheita que possa ser utilizado em condições adversas de relevo. Foi proposto o conceito de um mecanismo colhedor de macaúbas, de baixo custo, que funciona pelo princípio de vibrações mecânicas, e é capaz de trabalhar com eficiência em lavouras plantadas e maciços naturais. A partir de uma adaptação do método de Pahl e Beitz para desenvolvimento de projetos de máquinas, e a utilização do método de prototipagem de evolução, foram construídos protótipos de integração, que passaram por ensaio preliminar de campo. Foram realizadas algumas modificações em derriçadoras portáteis de café, que se constituíram em alterações no sistema de geração de sinais de vibração e foram transmitidos aos frutos de macaúba, na interface cabeçote/planta. Apenas um dos protótipos construídos foi considerado eficaz e adequado para realização posterior de avaliação de desempenho (protegida por meio de depósito de pedido de patente junto ao Instituto Nacional da Propriedade Industrial - INPI, sob o n.º BR 10 2017 010814 7). Para o projeto detalhado foram empregadas técnicas de CAD (Projeto Auxiliado por Computador). Posteriormente, foi possível observar a validação de eficiência da colheita dos frutos de macaúba pelo princípio de vibrações mecânicas. Nas condições em que ocorreram, os ensaios de campo demonstraram que a média da eficiência de colheita para o modelo proposto com varetas vibratórias foi de 97,4% e a média da capacidade de colheita foi de 566,91 kg h- 1.

Flowability is an important characteristic of handling process for efficiency and reliability purpose of post-harvest operations, which are governed by the physical properties of the product. Physical properties determination is an important factor for formulation of machinery projects and sizing of post-harvest operations, which may impact considerably on the products quality, influencing directly the operation cost and company profit. Thus, the objective of this work was to evaluate and determinate some physical properties (repose angle, unit and bulk density, porosity and color coordinates, particle size, moisture content, water activity, angle of internal friction and effective angle of internal friction) of coffee, such as to evaluate the influence of different roast and grinding degrees over these properties. Crude grain coffee (Coffea canephora and Coffea arabica), dehulled and dried were used. These were roasted at two levels: medium light and medium-dark brown, which Agtron numbers are, respectively, SCAA#65 and SCAA#45. After roasting process, grains were grinded at three particle sizes (thin, medium and thick). Both particle size and roast degree significantly affected physical properties of coffee. Coffee samples roasted at medium dark level obtained lower values of moisture content, water activity, repose angle, bulk and real density. Coffee samples grinded at level thin presented an increase of angle of internal friction and effective angle of internal friction, repose angle, bulk and real density, porosity and decrease of water activity values.