A spacecraft skin is being developed that assesses the severity of any damage it suffers from space debris and other impacts. The project, which is inspired by the behaviour of ants, is seen as the first step towards a self-repairing craft.
The team at CSIRO, Australia’s national research organisation, is working with NASA on the project and has so far created a model skin made up of 192 separate cells. Behind each cell is an impact sensor and a processor equipped with algorithms that allow it to communicate only with its immediate neighbours. Just as ants secrete pheromones to help guide other ants to food, the CSIRO algorithms leave digital messages in cells around the system, indicating for instance the position of the boundary around a damaged region. The cell’s processor can use this information to route data around the affected area.
The team hopes to refine the system so it can distinguish between different types of damage, such as corrosion and sudden impacts, which might require a rapid repair job. Other groups are developing impact sensor systems controlled by a centralised processor. But such systems would fail if the area containing the processor were damaged. So a distributed system could be much more reliable, says Bill Prosser of NASA’s Nondestructive Evaluation Sciences Branch in Langley, Virginia.
NASA’s ultimate aim is to create what it calls Ageless Aerospace Vehicles, which can detect, diagnose and fix damage.