Dynamic Analysis and Test of the Leaf Crushing Mechanism in the Sugar Cane Harvester
Abstract
In conventional sugarcane harvesters, leaves are stripped by high-speed rollers using strong impact, often causing stalk damage. This study proposes an innovative leaf-crushing mechanism that cuts and shreds leaves during conveyance, reducing the impact needed for subsequent stripping and minimizing damage. The Absolute Nodal Coordinate Formulation (ANCF) is employed to construct a cantilever beam model with equivalent torsional springs and an elastic foundation, accurately characterizing the component constraints. Hertz contact theory describes the collision with the stalk, and the system’s Lagrangian equations are derived via energy variation. Shear tests determine the leaf-fragmentation force threshold, informing the design. Numerical simulation analyzes the effects of roller center distance, radius, and speed on the impact force at the free end, yielding an optimized parameter set: 0.40 m center distance, 0.16 m radius, and 750-825 r/min speed. A prototype built with these parameters shows effective leaf shredding and markedly improved stripping completeness. At 800 r/min, the residual leaf rate for 150 stalks is 3 % with no stalk damage. Simulation and experimental results agree well, validating the model and mechanism. By integrating structural innovation with dynamic modeling, this work provides a new method and theoretical foundation for designing efficient, low-damage leaf-stripping systems in sugarcane harvesters.
