When harvesting Lycium barbarum L., excess amounts of detachments of the half-ripe fruit, unripe fruit, flowers, and leaves significantly affect the yield and adversely affect the subsequent processing, such as drying and grading. Finite element method (FEM) simulations and experiments of detachments were performed to harvest more ripe fruit and less half-ripe fruit, unripe fruit, flowers, and leaves. Three-dimensional (3D) models of the ripe fruit, half-ripe fruit, unripe fruit, flowers, leaves, fruit calyxes (flower calyx), fruit stems (flower stem), and branches were constructed using a 3D scanner, and material mechanics models of the above parts were established based on physical tests with universal testing machines. Detachment simulations and experiments of the ripe fruit, half-ripe fruit, unripe fruit, flowers, and leaves were performed to determine the detachment mechanisms and sequences. The detachment forces of each set of two parts were obtained. The field experiments showed that the detachment force between the fruit and calyx of ripe fruit was the lowest value of these forces, and only the ripe fruit was the first to detach from the calyx when harvesting. The results provided data support on the mechanics properties of wood and the optimization basis for the harvesting method of L. barbarum.

In a previously published study, to optimize the vibrating and comb-brushing harvesting, the main factors and their parameter values were obtained based on the FEM and RSM. However, the study was based on the extensive cultivation mode which need to be improve. To realize the mechanization of the harvesting of Lycium barbarum L., as well as to face the standardized hedge cultivation mode, a vibrating and comb-brushing harvester machine was designed, which was primarily composed of an execution system, a motion system, and a control system. The mathematical model between the harvest effect index and the operation parameters was established based on response surface methodology (RSM). The effects of various parameters on the harvest index were analyzed, and the best parameter combination was determined: a vibration frequency of 38.73 Hz, a brush speed of 14.21 mm/s, and an insertion depth of 26.07 mm. The field experiment showed that the harvesting rate of ripe fruit was 83.65%, the harvesting rate of unripe fruit was 7.22%, the damage rate of the ripe fruit was 11.49%, and the comprehensive picking index was 87.85. The findings provided a reference for the development of L. barbarum harvesting mechanization in a standardized hedge cultivation mode.

Design and optimization of torsion harvester of Lycium barbarum L.