Parameter Calibration of Cabbages (Brassica oleracea L.) Based on the Discrete Element Method

Abstract

The discrete element parameters of cabbages (Brassica oleracea L.) were calibrated for the design and parameter optimization of a cabbage harvester. The cabbage model was created based on the study of cabbage material characteristics and the simulation model parameters of cabbage were calibrated. The intrinsic parameters and partial contact parameters of cabbages were obtained by direct measurement. The cabbage accumulation angle was determined by a plate drawing test. Through the steepest ascent test and the orthogonal rotation combination test, a regression model of the cabbage accumulation angle error was established. The optimal contact parameters between the cabbages were obtained by the minimum error modeling. These calibrated parameters were applied in the verification test, and the results indicated that the error between the simulated and measured values of the cabbage accumulation angle was only 1.63%, which demonstrated that the results were dependable. This study can provide a theoretical support for designing and optimizing the parameters of cabbage harvesting machines with the discrete element method (DEM).