Abstract: Aiming at the problems of serious soil compaction, small row spacing, large tillage resistance and easy entanglement in tea gardens, a bionic shovel based on discrete element method was proposed, and its drag reduction performance was studied. The physical parameters of the compacted soil in tea garden were measured by discrete element simulation and experiment method. Taking the mole claw as the prototype, combined with its digging action, a tillage agency based on a four-bar mechanism was designed, and the drag reduction effects of the claw tip and claw profile of the mole claw were studied using the discrete element method. From the discrete element simulation results, it can be seen that under various tillage conditions, the average torque reduction ratio and power consumption reduction ratio of the claw-tip bionic feature were 1.72%-5.04% and 1.58%-4.84%, respectively. The average torque reduction ratio and power consumption reduction ratio of the claw profile bionic feature were 34.06%-39.29% and 29.02%-34.73%, respectively. The average torque reduction ratio and power consumption reduction ratio of the composite bionic feature were 36.61%-42.06% and 30.84%-38.15%, respectively. It can be seen that the drag reduction effects of the two bionic features could be superposed to a certain extent, and the combined bionic feature had a better drag reduction effect.

Key words: discrete element, tea garden soil, shallow tillage, bionics, drag reduction, parameter calibration