Mechanized harvesting of conilon coffee plants using a self-propelled machine

ABSTRACT Coffee is one of the main commodities of global agribusiness and of outstanding economic and social relevance for Brazil. The lack of labor and its high cost are factors that worry coffee producers, mainly during the conilon coffee harvesting, which is performed manually. This study aimed to evaluate the efficiency of a self-propelled harvester under different conditions of machine adjustment and conduction of the Coffea canephora crop and measure its influence on the cost of harvesting compared to manual harvesting. Harvesting speed (800 to 1600 m h-1), rotation of the vibrating rod cylinder (1.0 and 1.5 RPM), number of orthotropic branches (one, two, and three), and plants with and without plagiotropic branches in the lower third were assessed. The increase in harvesting speed reduced the efficiencies of stripping and harvesting and defoliation. Increasing from one to three orthotropic branches per plant increased harvesting and stripping efficiencies, fruit loss on the ground, defoliation, and reduced pending load. The management without plagiotropic branches showed higher harvesting efficiency, lower loss on the ground, and lower defoliation. Harvesting speeds from 800 to 1600 m h-1 reduced the total and unit costs up to 62% compared to manual harvesting. Increasing harvesting efficiency above 70% has reduced harvesting costs by up to 79% compared to manual harvesting.

摘要：咖啡是全球农业综合企业的核心大宗商品之一，对巴西具有突出的经济与社会价值。劳动力短缺及成本高企是令咖啡种植户忧心的突出问题，尤其在刚果咖啡（Coffea canephora，俗称conilon咖啡）的人工采收阶段。本研究旨在评估自走式采收机在不同机器调试参数与刚果咖啡种植管理模式下的作业效率，并对比其与人工采收的采收成本差异。试验共评估四类变量：采收速度（800~1600米·小时⁻¹）、振动棒滚筒转速（1.0与1.5转每分钟（RPM））、单株直立分枝数量（1、2、3个），以及植株下部三分之一区域是否带有斜生分枝的种植模式。
研究结果表明：采收速度提升会降低脱果效率、采收效率与落叶率；单株直立分枝数从1个增至3个时，采收与脱果效率显著提升，但地面落果量、落叶率随之增加，同时植株挂果负载量降低；采用下部无斜生分枝的种植管理模式时，采收效率更高，地面落果量更少，落叶率更低。当采收速度处于800~1600米·小时⁻¹区间时，总采收成本与单位采收成本较人工采收最多降低62%；当采收效率超过70%时，相较人工采收，采收成本最多可降低79%。