The US apple industry relies heavily on semi-skilled manual labor force for essential field operations such as training, pruning, blossom and green fruit thinning, and harvesting. Blossom thinning is one of the crucial crop load management practices to achieve desired crop load, fruit quality, and return bloom. While several techniques such as chemical, and mechanical thinning are available for large-scale blossom thinning such approaches often yield unpredictable thinning results and may cause damage the canopy, spurs, and leaf tissue. Hence, growers still depend on laborious, labor intensive and expensive manual hand blossom thinning for desired thinning outcomes. This research presents a robotic solution for blossom thinning in apple orchards using a computer vision system with artificial intelligence, a six degrees of freedom robotic manipulator, and an electrically actuated miniature end-effector for robotic blossom thinning. The integrated robotic system was evaluated in a commercial apple orchard which showed promising results for targeted and selective blossom thinning. Two thinning approaches, center and boundary thinning, were investigated to evaluate the system ability to remove varying proportion of flowers from apple flower clusters. During boundary thinning the end effector was actuated around the cluster boundary while center thinning involved end-effector actuation only at the cluster centroid for a fixed duration of 2 seconds. The boundary thinning approach thinned 67.2% of flowers from the targeted clusters with a cycle time of 9.0 seconds per cluster, whereas center thinning approach thinned 59.4% of flowers with a cycle time of 7.2 seconds per cluster. When commercially adopted, the proposed system could help address problems faced by apple growers with current hand, chemical, and mechanical blossom thinning approaches.
翻译:美国的苹果产业在必要的田间操作,如培训、修剪、开花和小果修整以及收获方面严重依赖半熟练的手工劳动力。开花修剪是实现期望的货载、果实品质和多次开花的重要作物负载管理实践之一。虽然存在多种技术,如化学和机械修剪,但这些方法经常产生无法预测的修剪结果,可能会损坏树冠、枝块和叶组织。因此,种植者仍然依赖费力、费力和昂贵的手工开花修剪以实现所需的修剪结果。本研究提出了一种用于苹果园的机器人开花修剪解决方案,其中使用了人工智能的计算机视觉系统、六自由度机器人机械手以及电驱动小型末端执行器用于机器人开花修剪。集成的机器人系统已在商业苹果园中进行评估,其表现出针对性和选择性的开花修剪具有良好的效果。评估了两种修剪方法,即中心修剪和边界修剪,以评估系统能够从苹果花簇中移除多样的花朵。在边界修剪期间,末端执行器围绕簇边界进行操作,而在中心修剪中,仅在簇的质心进行执行器操作,持续时间为 2 秒。边界修剪方法从被选中的簇中修剪掉了 67.2% 的花朵,每个簇的循环时间为 9.0 秒,而中心修剪方法从每个簇中修剪掉了 59.4% 的花朵,每个簇的循环时间为 7.2 秒。当被商业化采用时,所提出的系统可以帮助解决苹果种植者在当前手工、化学和机械开花修剪方法面临的问题。