Advanced Design and Performance Evaluation of an Automatic Synchronized Grafting Machine for Solanum Vulgare

The adoption of grafting machines has become an essential trend in the advancement of the vegetable nursery industry, driven by the aging population and the rapid growth of the vegetable sector. Domestic and foreign research organizations have designed various types of vegetable grafting devices for the huge nursery market. However, most of the machines developed and designed at home and abroad are now semi-automated and are thus highly susceptible to damaging the stems of the seedlings during operation. Therefore, in order to realize the complete automation of the grafting operation and improve the grafting survival rate and quality, in this paper, eggplant hole tray seedlings were grafted as the object, and the cutting mechanism, the integrated mechanism of clamping and fitting, and the wrapping mechanism were structured on the basis of the affixing method. The transition conversion from semi-automatic to fully automatic was realized. And the rationality of the design was verified via the cutting test and the clamping characteristic test, which maximized the fit rate between the cutting surface of the rootstock and the scion seedling and maximized the protection of the grafted seedling from damage in the clamping process. Finally, the device was tested using Torubam rootstock and a Nova 101 tomato scion. The results showed that the optimal cutting angles were 35° and 30° for rootstock and scion, respectively, and that the lengths of the cutting surfaces were 11.28 ± 0.18 mm and 11.43 ± 0.14 mm. The grafting efficiency of the machine was up to 700 grafts per hour, with an average grafting success rate of up to 95% and zero stem damage to the seedlings. The experiments proved that the structure design of the machine is reasonable, and it can fully improve the grafting efficiency and quality. Meanwhile, the research findings can provide a theoretical basis for the application of the latter in the field of plant grafting. The research results can effectively alleviate the dependence on manual labor in the nursery industry and further liberate the labor force.