Innovative Design of Rotary Till Blades to Reduce Cutting Resistance

Rotary tillage in cohesive, salt-affected soils requires significant energy, making the optimization of blade geometry essential to reduce resistance. This study takes inspiration from the digging claw of the brown bear (Ursus arctos) to design a bio-inspired rotary blade and assess its performance using a calibrated discrete element method (DEM) model and soil bin experiments. The DEM model was specifically calibrated for the salt-affected soils of the Yellow River Delta. Key parameters for the study were identified using a Plackett-Burman test and optimized through a central composite design, with experimentally measured draft force as the response variable. The performance of the bio-inspired blade was compared to that of a conventional IT-type blade, focusing on torque demand and soil fragmentation. Simulation results indicated that the bio-inspired blade reduced torque by up to 13% across a rotational speed range of 160-320 RPM and by up to 11% at tillage depths of 60-140 mm. Soil bin tests reinforced these findings, showing that the bio-inspired blade required 17.8% less torque than the IT-type blade. However, the IT-type blade achieved a slightly higher soil fragmentation rate, exceeding the bio-inspired design's performance by 3.9%. This study demonstrates that biomimetic design can significantly reduce energy requirements for rotary tillage while maintaining effective soil fragmentation.