In this study, a bionic foot with sand fixation and fluidization limitation functions was designed. Also a rectangular foot with the same sizes, named the common foot, was designed for comparison. Three kinds of quartz sands were selected to study how particle size, shape and compactness affected the intrusion performances of mechanical feet. The intrusion resistive forces and pressures of the bionic foot on these three kinds of quartz sands were all smaller compared with the common foot. Discrete element simulations showed particle disturbance areas were smaller and particle motion trends were more consistent under the bionic foot versus the common foot. The intrusion resistive forces of these two kinds of mechanical feet firstly increased and then decreased with the increasing particle sizes of quartz sands. Moreover, the intrusion resistive force on spherical particles was less than that of irregular particles for both the bionic foot and the common foot. The corresponding resistive forces of mechanical feet were characterized based on quartz sand compactness. The classic pressure-sinkage model was modified based on the intrusion tests, and the relationships between intrusion resistive force and mechanical foot depth were obtained.

本研究设计了一种具有固沙和流化限制功能的仿生足。还设计了一个尺寸相同的矩形脚，称为普通脚，用于比较。选取三种石英砂，研究粒度、形状和密实度对机械脚侵入性能的影响。仿生足对这三种石英砂的侵入阻力和压力均小于普通足。离散元模拟表明，仿生足与普通足相比，粒子扰动区域更小，粒子运动趋势更一致。这两种机械脚的侵入阻力随着石英砂粒径的增大先增大后减小。而且，仿生足和普通足对球形颗粒的侵入阻力均小于不规则颗粒。基于石英砂的致密性表征了机械脚的相应阻力。在入侵试验的基础上对经典的压沉模型进行了修正，得到了入侵阻力与机械足深的关系。