Abstract
The problem of aging agricultural labor force and urbanization of population is becoming increasingly serious worldwide, labor shortage has become a key factor restricting the development of the fruit and vegetable industry. Especially in the field of apple cultivation, the low level of mechanization and high labor cost in the picking process have become the obstacle limiting the further development of the industry. In order to solve the problem of fruit damage caused by improper handling of fruit stems during apple picking, an innovative apple stem shear end-effector was designed in this study. The design especially considered the calyx structure (between the apple fruit and the stem) and compared the shearing effect of three different curvature (pointed, circular and elliptical) blades on the stem at 15°, 30°, and 45° of opening angle. At the same time, the possible damage to the fruit caused by these designs was analyzed. First, a 3D model was created based on the physical dimensions of real apples. Then, the overall device of the end-effector was designed, including the power unit, transmission structure and blade part. In the simulation analysis, the model was imported into ANSYS software, and the load step and boundary conditions were set to perform finite element analysis to verify the feasibility and reliability of different designs. The simulation results showed that the elliptical tool with an open edge of 45° performed best in shearing the fruit stems and was able to accomplish the shearing task without damaging the fruits. This result provides a reference for the future design of fruit and vegetable stem shearing mechanisms with special structural characteristics, and is expected to play an important role in improving the efficiency of agricultural production and reducing production costs.
Get full access to this article
View all access options for this article.