Development of a generator-powered self-propelled automatic tray loading/unloading machine for use in rice nurseries

The objective of this study was to develop a generator-powered self-propelled automatic tray loading/unloading machine for rice seedling nurseries by using a gantry as the transport system to automate seedling tray placement and harvesting. During input operations, seedling trays are transported by conveyor belts to the nursery, and the tray loading/unloading machine automatically places the trays in rows in the nursery. During output operations, the tray loading/unloading machine automatically gathers the seedling trays from the nursery and transports them on conveyor belts to an automatic seedling mat roller. The entire system comprises mechanical components that achieve high operational stability and few malfunctions. Using a programmable logic controller for automation can effectively alleviate the inconvenience of laying heavy power cables. The tray loading/unloading machine automatically moves along the trusses of the gantry transport system, placing seedling trays in rows in the nursery. Alternatively, it can reverse directions and gather seedling trays from the nursery and transport them to the conveyor belts. The tray unloading capacity is 741 trays per hour, and tray loading capacity is 763 trays per hour. The tray loading/unloading machine enhances the automation operation of rice seedling nursery and alleviates the difficulty in hiring workers in farming villages where there are a shortage of labor.