Greenhouse Robots: Ultimate Solutions to Improve Automation in Protected Cropping Systems—A Review

In recent years, agricultural robotics has received great attention in research studies, being considered a way to address some important issues of the agricultural sector, such as precision agriculture, resources saving, improvement of safety conditions, and shortage of human labor. These issues are particularly relevant in greenhouse production systems, where many highly repetitive and sometimes dangerous operations are still required to be performed by humans. The purpose of the present review is providing an overview of the research conducted in recent years related to robotic automation for greenhouse applications. The currently available literature about robots and automated solutions for greenhouse applications has been reviewed through the consultation of international databases of journals. A total of 38 publications were included after screening and the information related to each retrieved automated solution was classified. The research highlighted great variability among studies, which often describe automation solutions designed for specific crops and define the specific “supporting tasks” necessary for the completion of a “main task”. Specifically, the technologies used for guidance and navigation systems, crop detection and fruit grasping system, spraying system, and other minor supporting tasks have been described. Furthermore, a critical appraisal of the main challenges of the sector and future research directions are provided.