An evaluation of African eggplant fruits engineering properties in relation to robotic harvesting

Abstract

The construction and application of eggplant harvesting robot required some basic physical characteristics and mechanical properties of the eggplant fruit. The physical characteristics (geometric mean diameter, surface area, volume, sphericity, and weight), and mechanical properties (failure energy, failure force, deformation, shear resistance, and shear force) of the Africa beauty eggplant fruits, were evaluated at three different maturity stages in this study. The maturity stages adopted in this study were 21 days after peak anthesis (DAPA), 28 DAPA, and 35 DAPA. The results obtained showed that the maturity stage resulted in a significant effect (p<0.05) on the mechanical properties of the eggplant fruits. The geometric mean diameter, surface area, volume, sphericity, and weight of the fruits significantly increased as the fruits matured from 21 DAPA to 35 DAPA (p<0.05). The failure energy, failure force, shear resistance, and shear force of the fruits were fluctuating during maturity; fruits harvested at 21 DAPA recorded the lowest values, while those harvested at 28 DAPA recorded the highest values. In addition, the study revealed that the loading position had a significant effect on the mechanical properties of the fruits (p<0.05). The best eggplant harvesting robot properties obtained in this study was at 28 days after peak anthesis (DAPA). The physical characteristics and mechanical properties results of eggplant fruit, obtained in this study will be useful information for the application in the design and construction of eggplant fruits robot harvesting.