An obvious disadvantage of steel beings, when compared to us meatmachines, is that they lack they ability to regenerate and heal after having suffered damage. But the future isn’t bleak for them — we’re inching closer to realistic solutions to this problem.

An assembly of scientists and engineers working under the Microvascular Autonomic Composites Initiative (µVAC) are creating materials with a microvascular network, capable of pumping self-healing polymers — or in other words: materials with veins that carry materials for healing.

The material is layered. The substrate layer, shown on the picture on the left in red, and the surface layer shown in purple. A microvascular network (series of tubes) is embedded in the substrate layer and carries the healing agent. The surface layer acts as a catalyst for the healing agent, causing it to polymerize upon contact. This allows the healing agent to maintain liquid form, avoiding clogging the veins themselves, right up until damage is inflicted on the surface layer. A very important aspect of their implementation, is that the skin can heal a crack at the same spot not just once — but up to seven times (4 times average with the strongest healing agent concentration). The image below shows residue healing agent repairing cracks on the surface of the µVAC material.

The initiative is a partnership between the University of Illinois at Urbana-Champaign (UIUC), Duke University, the University of California Los Angeles (UCLA) and the Harvard Medical School. As described on their site:

μVAC was conceived in response to a new paradigm in materials design, that of autonomy – the ability to achieve adaptation and response in an independent and automatic fashion. The central vision of μVAC is the synthetic reproduction of autonomic biological functions, obtained through the creation and integration of complex materials systems with three-dimensional microvascular network architectures.

Quite fascinating research and ideas. Skin capable of healing, even though only to a certain degree, could prove incredibly useful for the robotics industry. Space mission robots immediately spring to mind, as well as other robots that must work in hazardous environments away from our organic helping hands. The final picture here is to show the scale of the material — which graphically explains the µ in µVAC.

References and Links

• Image credit: µVAC, Kathleen Toohey & Janet Sinn Hanlon (UIUC)
• Microvascular Autonomic Composites Initiative (µVAC)
• Latest paper published in Nature Materials (PDF), or their list of publications