PERFORATION-TYPE ANCHORS INSPIRED BY SKIN LIGAMENT FOR THE ROBOTIC FACE COVERED WITH LIVING SKIN

Abstract Skin equivalent, a living skin model composed of cells and extracellular matrix, possesses the potential as an ideal covering material for robots due to their biological functionalities. To employ skin equivalents as a coverage material for robots, a secure method for attaching them to the underlying structure is required. In this study, we developed a perforation-type anchor inspired by the structure of skin ligaments as a technique to effectively adhere skin equivalent to robotic surfaces, ensuring a smooth and non-protrusive integration, akin to natural skin adherence. We showed the effectiveness of plasma treatment for collagen-gel penetration within the perforation-type anchor. In characterizing the anchoring system, we investigated the impact of anchor diameter on preventing contraction and changes in holding strength. To showcase the versatility of perforation-type anchors in three-dimensional (3D) coverage applications, a 3D facial mold with intricate surface structure was covered with skin equivalent. Furthermore, we constructed a robotic face covered with dermis equivalent, capable of expressing smiles with the actuation to the skin equivalent through perforation-type anchors. This research introduces an approach for the adhesion and actuation of skin equivalent with perforation-type anchors, potentially contributing to advancements in biohybrid robotics technology.