Design of bionic rotary tiller blades based on marmot claws and research on anti-entanglement and drag reduction performance

Returning straw to the field helps retain soil moisture, enhance drought resistance, reduce erosion, improve soil fertility, and increase crop yield. To address the issues of straw entanglement and high resistance during rotary tillage after wheat harvest, a new bionic rotary tillage blade (B-RTB) was designed based on the claw structure of the Xinjiang marmot using reverse engineering. Dynamic analysis of the B-RTB was conducted, and a discrete element model of the straw–soil–tool interaction was developed for simulation experiments. Using the working inclination angle and the cutting edge angle of the B-RTB as test factors, and considering rotary torque and the number of straw bond breaks as evaluation indicators, a quadratic regression orthogonal rotation experiment was designed. The optimal parameter combination was identified as a tooth profile working inclination angle of 123° and a cutting edge angle of 31° Field performance tests under various operating conditions demonstrated that, compared with a conventional rotary tillage blade (O-RTB), the B-RTB significantly reduced operating resistance under the same forward speed and power output conditions, with an energy consumption reduction rate of 12.85%. Across different working conditions, the B-RTB achieved a straw crushing qualification rate between 83.51% and 89.36%, and a straw coverage rate of 93.24%. It effectively mitigates straw entanglement and reduces tillage resistance. These findings provide valuable insights for the bionic structural design of soil-engaging components and contribute to research on anti-entanglement and drag reduction.