Analysis of friction on human fingers and design of artificial fingers

In many cases of human hand tasks, grasping and manipulation of objects are the most basic motions. However, the influence of physical characteristics of human finger on grasping motions have not yet been sufficiently clarified. For example, friction which is an important characteristic of grasping motions has hardly been investigated. In this study, we pay attention, to friction between a finger and an object. First, we develop a system to measure the friction on fingers. Next, based on the experimental results obtained from the measurement system, we propose a new model for the maximum static friction force on human fingers. Also, we find that the friction forces are changed depending on the directions of tangential forces. Finally, we realize a finger-tip which is made of silicone and whose characteristics are similar to those of human fingers.