Self-healing skin for robotics

According to ScienceDirect, studies indicate a general preference for robots to look more humanoid, particularly in contexts where robots are intended for social interaction.

Researchers from the Department of Mechano-Informatics, Graduate School of Information Science and Technology, The University of Tokyo, have found a way to create self-healing skin that enables robotic surfaces to exhibit properties akin to human skin using cutting-edge technology to integrate living cultured skin onto robotic structures using perforation-type anchors inspired by human skin ligaments.

Composition and manufacturing process

The self-healing skin comprises two main layers: the dermis and the epidermis. The dermis equivalent is fabricated by pouring a collagen gel containing normal human dermal fibroblasts (NHDFs) into a device equipped with perforation-type anchors. These anchors, modelled after human skin ligaments, ensure secure attachment and effective distribution of the gel. The collagen gel is crosslinked in an incubator, allowing cells to adhere and remodel the matrix over seven days, forming a mature dermis equivalent.

Next, the epidermis layer is constructed by seeding normal human epidermal keratinocytes (NHEKs) onto the dermis equivalent. This two-step process results in a skin equivalent with self-healing properties, capable of repairing minor damages autonomously through cellular proliferation.

Perforation-type anchors

The perforation-type anchors are crucial for attaching the skin equivalent to robotic surfaces. These anchors consist of V-shaped holes into which the collagen gel penetrates, securing the skin to the underlying structure. A water-vapour-based plasma treatment enhances the wettability of the anchors, ensuring thorough gel infiltration. This method provides a secure and aesthetically pleasing attachment, avoiding the drawbacks of traditional protrusion anchors.

Applications and benefits

The self-healing skin has significant implications for robotics, particularly in humanoid robots requiring lifelike capabilities:

• Self-healing: The ability to repair minor scratches and damages autonomously ensures long-term durability and reduced maintenance.
• Versatility: The perforation-type anchors allow the skin to cover complex three-dimensional structures, such as robotic faces, enabling natural facial expressions.
• Biohybrid robotics: Integrating living tissue with robotic components opens new possibilities in creating robots that closely mimic human biology.

3D engineering

The fabrication process involves advanced engineering techniques, including 3D printing and plasma treatment.

The 3D printed devices create precise moulds for the skin equivalent, while the plasma treatment ensures effective gel penetration and secure attachment. These methods enable the construction of complex, lifelike robotic surfaces.

Future prospects

The development of self-healing skin for robotics marks a significant advancement in the field of biohybrid robotics. Future research may focus on enhancing the toughness of the dermis equivalent through longer cultivation periods and exploring the integration of cultured muscle tissue for more natural movements. Additionally, this technology has potential applications beyond robotics, such as in the cosmetics and medical industries, providing new insights into skin repair and regeneration.

The self-healing skin represents a major breakthrough in robotics, combining advanced materials science and engineering to create lifelike, durable robotic surfaces. This innovation paves the way for more resilient, human-like robots capable of operating in diverse and unpredictable environments.