Seedling pickup mechanisms for automatic transplants: a review of technologies and future developments

Research on fully automatic transplanting is important for improving operational efficiency, alleviating labor shortages and reducing costs. The design and optimization of the seedling pickup mechanism are central to this field of study. This paper presents an analysis of the current research status of seedling pickup mechanisms worldwide. It summarizes their working principles and categorizes them based on their operational targets into plug-gripping type, push-clamp combination type and stem-gripping type. The analysis reveals that existing seedling pickup mechanisms face challenges in the positioning accuracy of the gripper claws, as well as in the comprehensive success rate of accurate seedling pickup and placement. Also, they exhibit adaptability issues concerning the variety of crops, agronomic practices and terrain conditions. This paper also examines the inevitable problem of seedling damage, analyzing its causes and potential detection methods. It is recommended that future research should aim for high speed, high accuracy, low damage, intelligence and enhanced versatility. These efforts will facilitate the subsequent optimization of seedling pickup mechanisms for fully automatic transplanters and promote their overall development.