Control method of seedbed compactness based on fragment soil compaction dynamic characteristics
Seedbed preparation is the initial and fundamental operation for achieving an optimal soil condition for vegetable production. Seedbed compaction is an important technical criterion for evaluating the operating performance of a soil preparation machine. To analyze the dynamic properties of fragment soil compaction after rotary tillage, a discrete element method (DEM) was used to simulate the compaction process, and the Edinburgh elasto-plastic adhesion model (EEPA) was selected to calculate the interaction force between compact roller and fragment soil. The relationship models between compact force and soil compactness at different machine forward speeds and compaction depths were established. Then, it was proposed to control the soil compaction by adjusting the compaction depth, and the adjustment range of compaction depth was calculated using the fuzzy algorithm which taking the compact force as input parameter. In order to reduce the effect of compact force fluctuations and improve the stability of control system, the adjustment strategy was formulated according to the statistical analysis of fuzzy calculation outputs over a period of time. Field experiment results indicated that the seedbed compaction could be automatically adjusted in real time according to the set compact force. Compared with the traditional method of using a constant compaction depth, the stability of soil compaction was significantly improved. The proposed method is useful for improving the working performance and adaptability of soil preparation machines in different field environments.
Keywords: Soil preparation machine, Seedbed compaction, Discrete element method, Dynamic analysis, Compaction depth control