Optimized tuber-lifting velocity model for cassava harvester design

Abstract

The lack of optimized lifting velocity model for cassava tuber lifting results in the shortage of evidence of design of lifting velocity control system and large harvest loss during mechanized harvesting of cassava. First, an optimized velocity model of manually pulling tubers and a velocity model of mechanical lifting tubers were established using physical experiments. And then using the mechanical tuber-lifting velocity model, the mathematical models between coefficients of mechanical tuber-lifting velocity model and cassava harvesting quality were established based on numerical simulation and regression analysis. Moreover, the coefficients were optimized using optimization method and the mechanical optimal tuber-lifting velocity model was obtained. Finally, the optimization results and the mechanical optimal tuber-lifting velocity model were verified by simulation and physical experiment, respectively. The results show that the optimized manual pulling velocity model can be superimposed by a line and a sine curve or a concave downward parabola and a sine curve. The optimal coefficients’ combination of mechanical tuber-lifting velocity model is shown as follows: A = 0.056, B = 0.521, C = 0.048, D = 0.086, E = 38.506, and F = 1.165. The mechanical optimal tuber-lifting velocity model’s expression is simple and the model is reasonable. The mechanical optimal tuber-lifting velocity model, which is established using physical experiments, simulation method, and optimization technique, has great significance for designing lifting velocity control system.