Scientists at NASA's Jet Propulsion Laboratory (JPL) are honing the applications of a gecko-like gripping mechanism in the hope of making life a little less 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 the station, and have even equipped a robot with the tech, opening up the possibility of allowing it to safely operate on the exterior of the space station.
Living in space is considerably more difficult than it is back on Earth. Everything is just that little bit more floaty, and whilst astronauts have an impressive arsenal of contraptions and railings to hang on to up there, it's inevitable that the general lack of gravity is going to hurt productivity. Using a biomimetic approach, NASA scientists are planning to give astronauts a new and highly versatile tool with which to manipulate the unruly microgravity environment.
The team at JPL were inspired in the design of the new anchors by the gecko. In the wild, the gecko has a natural aptitude for climbing thanks to a remarkable evolutionary trait – the reptile's feet are covered with millions of hairs that grip their target with what is known as van der Waals force.
The van der Waals force is an unusual quirk of physics that occurs when electrons orbiting the nuclei of an atom are unevenly distributed, creating an electric field with a positive and negative pole. This electric field creates a matching polarity in nearby molocules, forming a temporary adhesive effect between the gecko's feet and whatever they are touching.
By creating a synthetic material composed of tiny stalks much smaller than a human hair, scientists at JPL were able to mimic the gecko's impressive gripping abilities. The result is a powerful and flexible anchor that requires no mating technology, allowing them to be placed on any flat surface of the ISS and affixed by simply pushing together two components of the grip.
Three sizes of anchor have been created so far – 1 x 4 inches (2.5 x 10 cm), 2 x 6 inches (5 x 15 cm) and 3 x 8 inches (7.6 x 20 cm) – but the men and women at the JPL are starting to think of ever more ambitious applications for the technology. One possible application would be to use the gecko grippers to capture large pieces of space junk, such as the upper stages of launch vehicles or derelict satellites, as part of an effort to de-clutter low-Earth orbit.
The technology is also being considered for use on future satellite servicing missions, and one application even envisions using the grippers to allow robots, such as the agency's experimental Limbed Excursion Mechanical Utility Robot (LEMUR), to clamber over the hull of the ISS and future space stations undertaking servicing and making repairs.
"Lemur could be an astronaut's pet monkey," states JPL engineer Brett Kennedy, principal investigator for the robotic project. "It can perform tasks that are too small for astronauts to do easily. It's built to get into the nooks and crannies of a structure."
It is envisioned that the LEMUR will essentially be an all-purpose robot, designed with extreme flexibility in mind, and sporting limbs adaptable to numerous tasks. The robot's circular body makes the robot capable of moving in any direction without the need to re-orientate, and the all-terrain nature of the gecko grip could one day see LEMUR exploring the Martian landscape.
Source: NASA JPL