NASA testing climbing space robot with sticky gecko feet

Inspired by geckos, NASA has equipped a climbing robot with next-generation sticky feet that could help them carry repair work on the International Space Station (ISS).

Thanks to tiny hair on the bottom of geckos' feet, these lizards can cling to walls with ease, and their stickiness doesn't wear off with repeated usage.

Aaron Parness from NASA's Jet Propulsion Laboratory in California and colleagues used that concept to create a material with synthetic hairs that are much thinner than a human hair.

When a force is applied to make the tiny hairs bend, that makes the material stick to a desired surface. "This is how the gecko does it, by weighing its feet," Parness said.

The newest generation of grippers can support more than 150 Newtons of force, the equivalent of 16 kilogrammes.

In a microgravity flight test last year through NASA's Space Technology Mission Directorate's Flight Opportunities Programme, the gecko-gripping technology was used to grapple a 10 kilogramme cube and a 100 kilogramme person.

Researchers have more recently made three sizes of hand-operated "astronaut anchors," which could one day be given to astronauts inside the ISS. The anchors are made currently in footprints of 1 by 4 inches, 2 by 6 inches and 3 by 8 inches.

They would serve as an experiment to test the gecko adhesives in microgravity for long periods of time and as a practical way for astronauts to attach clipboards, pictures and other handheld items to the interior walls of the station.

Astronauts would simply attach the object to the mounting post of the gripper by pushing together the two components of the gripper. Parness and colleagues are collaborating with NASA's Johnson Space Centre in Houston on this concept.

They are also testing the Lemur 3 climbing robot, which has gecko-gripper feet, in simulated microgravity environments. The team thinks possible applications could be to have robots like this on the space station conducting inspections and making repairs on the exterior.

For testing, the robot manoeuvres across mock-up solar and radiator panels to emulate that environment. There are numerous applications beyond the space station for this technology, NASA said.

"We might eventually grab satellites to repair them, service them, and we also could grab space garbage and try to clear it out of the way," Parness said.