Scientists at NASA'sJet Propulsion Laboratory (JPL) are honing the applications of agecko-like gripping mechanism in the hope of making life a littleless chaotic for those working aboard the International Space Station(ISS). The ever-inventive JPL workers have come up with a series of"astronaut anchors" for use both inside and outside thestation, and have even equipped a robot with the tech, opening up thepossibility of allowing it to safely operate on the exterior of thespace station.
Living in space isconsiderably more difficult than it is back on Earth. Everything isjust that little bit more floaty, and whilst astronauts have animpressive arsenal of contraptions and railings to hang on to upthere, it's inevitable that the general lack of gravity is going tohurt productivity. Using a biomimetic approach, NASA scientists areplanning to give astronauts a new and highly versatile tool withwhich to manipulate the unruly microgravity environment.
The team at JPL were inspired in the design of the new anchors by thegecko. In the wild, the gecko has a natural aptitude for climbingthanks to a remarkable evolutionary trait – the reptile's feet arecovered with millions of hairs that grip their target with what isknown as van der Waals force.
The van der Waals force is an unusual quirk of physics that occurs whenelectrons orbiting the nuclei of an atom are unevenly distributed,creating an electric field with a positive and negative pole. Thiselectric field creates a matching polarity in nearby molocules,forming a temporary adhesive effect between the gecko's feet andwhatever they are touching.
By creating a syntheticmaterial composed of tiny stalks much smaller than a human hair,scientists at JPL were able to mimic the gecko's impressive grippingabilities. The result is a powerful and flexible anchor that requiresno mating technology, allowing them to be placed on any flat surfaceof the ISS and affixed by simply pushing together two components ofthe grip.
Three sizes of anchorhave been created so far – 1 x 4 inches (2.5 x 10 cm), 2 x 6inches (5 x 15 cm) and 3 x 8 inches (7.6 x 20 cm) – but the menand women at the JPL are starting to think of ever more ambitiousapplications for the technology. One possible application would be touse the gecko grippers to capture large pieces of space junk, such asthe upper stages of launch vehicles or derelict satellites, as partof an effort to de-clutter low-Earth orbit.
The technology is alsobeing considered for use on future satellite servicing missions, andone application even envisions using the grippers to allow robots,such as the agency's experimental Limbed Excursion Mechanical UtilityRobot (LEMUR), to clamber over the hull of the ISS and future spacestations undertaking servicing and making repairs.
"Lemur could be anastronaut's pet monkey," states JPL engineer Brett Kennedy,principal investigator for the robotic project. "It can performtasks that are too small for astronauts to do easily. It's built toget into the nooks and crannies of a structure."
It is envisioned thatthe LEMUR will essentially be an all-purpose robot, designed withextreme flexibility in mind, and sporting limbs adaptable to numeroustasks. The robot's circular body makes the robot capable of moving inany direction without the need to re-orientate, and the all-terrainnature of the gecko grip could one day see LEMUR exploring theMartian landscape.
Source: NASA JPL