载荷对壁虎刚毛束的摩擦各向异性特性影响的实验研究

摘要

The load effect on the anisotropic friction property of gecko seta arrays have been experimentally investigated on a homemade micro adhesive and friction force detect device with isolated seta arrays.The result shows that when sliding against the direction of the seta curvature to grip out,the friction force is proportional to the normal load with a friction coefficient of about 0.6.When sliding along the direction of the seta curvature to grip in,the normal preload force could be fully or partly transformed into adhesion force and repulsive force while friction force rapidly rose with the increment of the applied preload.Under the same normal preload,the lateral friction force in grip in is more than twice of that in grip out.These properties of anisotropy in friction and adhesion are determined by the micro and nano-structures of setae.%用离体壁虎刚毛阵列在自制微黏附摩擦测试台上对预加载荷对刚毛摩擦与黏着的各向异性特性的影响进行了实验研究.实验结果表明,在逆壁虎刚毛自然弯曲方向卷出实现脱附时,刚毛所受摩擦力与法向力成正比,摩擦系数为0.6;沿顺刚毛自然弯曲方向卷入实现黏附时,随预载荷增加摩擦力增加,法向力由黏附力变为斥力.在同等预载荷下,卷入方向的摩擦力是卷出方向的2倍以上.本文提出了摩擦各向异性特征参数,对壁虎刚毛的黏着与摩擦各向异性进行了定量表征。这种特性是由刚毛的弯曲及多等级结构决定的.