For robot hands that physically interact with humans, ensuring contact safety and accurately understanding contact conditions are crucial. In this study, we propose a novel soft, fingertip-mounted sensor capable of estimating both contact force and position. The sensor utilizes silicone rubber tubing, an inherently elastic material, to guarantee high contact safety. It's constructed by orthogonally stacking layers of silicone rubber tube rows. This unique design allows for the estimation of contact force increases or decreases in four distinct regions based on changes in the internal pressure within each tube row. Furthermore, by analyzing the balance of contact forces across these regions, the approximate point of force application can also be estimated. Our contact force estimation experiments showed instances where errors reached approximately 25%. Nevertheless, the system could largely estimate the change (increase or decrease) in contact force with accuracy. Furthermore, approximating the contact position was also feasible.
MONMA et al. (Wed,) studied this question.