NASA is getting into the textile business thanks to a team led by systems engineer Raul Polit Casillas at the Jet Propulsion Laboratory in Pasadena, California. The team has unveiled prototype swatches of a new metallic "space fabric" created using 3D printing that incorporates advanced functions that would be beneficial for use in space.
To the naked eye, the space fabric looks like a cross between chain mail and metallic tiles, like something you might see in one of the more "with it" haute couture dresses of the Swinging Sixties. But this odd design is more than a fashion statement, with one side of the fabric that can reflect light and heat, while the opposite side absorbs it. NASA says that by folding the material in different ways, it can conform to various shapes and produce the desired levels of reflectivity, passive heat management, and tensile strength.
The fabric was produced using additive manufacturing, where an object isn't milled or assembled, but built up layer by layer in one piece using streams of molten polymers or sintering metallic powders using precisely controlled lasers or electron beams. This allows for items to be made of very few parts needing final assembly, speeds up prototyping, greatly reduces costs, and allows for designs that would be impossible to produce using conventional methods.
In the case of the space fabric, Polit Casillas prefers to call this "4D printing" because it allows engineers to print both a desired geometry and function directly into a material. This control also allows a material to incorporate multiple functions as well as produced organic, non-linear shapes at relatively low cost.
The space agency sees the fabric as potentially having a variety of applications, including large antennas that can be folded and change shape quickly, and insulation for spacecraft visiting cold, icy moons and planets. It could also be used in flexible, insulated foot pads that would give landers and rovers a firm footing without melting the ice beneath them, micrometeorite shields for spacecraft, astronaut spacesuits, and for collecting samples on other planets.
The team hopes that such fabrics will not only be used in space, but manufactured there as well as a means of conserving and recycling scarce resources aboard spacecraft. In addition, it could also change the way spacecraft are engineered, allowing them to be created "whole cloth" instead of many discrete components that increase the potential points of failure.
"I can program new functions into the material I'm printing," says Polit Casillas. "That also reduces the amount of time spent on integration and testing. You can print, test and destroy material as many times as you want."
The octopus is an odd creature. The mollusc's large brain makes it a good problem solver, it has the ability to change color in double quick fashion, can dart off suddenly in a cloud of blackish ink and the lack of a skeleton allows it to squeeze through the tightest of spaces. But it's the creature's prehensile arms that inspired German automation firm Festo to create a versatile gripper for the production line of tomorrow. We brought you a quick introduction yesterday, so now let's take a closer look at the OctopusGripper.
The Future Concepts robot has been designed to safely pick up, securely hold and gently put down objects in the workplace. Rather than being developed with a specific gripping function in mind, the OctopusGripper can multitask – meaning that should the production line change, the flexible device can be adapted instead of replaced, potentially saving costs.
Like the animal that inspired its creation, the OctopusGripper's 22 cm (8.6 in)-long tapered tentacle has two rows of suction cups. Its soft silicone structure has a chamber running along its length that causes the tentacle to bend inwards when compressed air is applied, wrapping itself around objects of varying shapes. Festo's engineers surrounded the chamber with a Lycra fiber cover to restrict its expansion and protect the silicone outer skin from bursting, while a wafer-thin polystyrene film has been installed in the middle of the tentacle to make sure that the structure only bends inwards.
Designed to grip securely but gently, so as not to crush or damage whatever it is holding, the small suction cups at the thin end of the tentacle attach to the surface of an object passively, but eight of the larger cups at the other end are connected to a vacuum line that can be actively engaged during the gripping process. Festo also says that the components installed within the tentacle are elastic and deformable, making for safe human/robot collaboration in the workplace.
The OctopusGripper is controlled and regulated by the world's first pneumatic automation platform – the Festo Motion Terminal – which allows for precise control over compressed air flow rate and activation. This app-based software system can control more than 50 individual components.
Festo's Bionic Learning Network has designed two pneumatic robot arms with which to test the gripper's collaborative working potential. Agonist and antagonist interplay are applied for the movement of the BionicCobot's seven joints, which is programmed using the Motion Terminal interface, though it has a manual control panel on its side, too.
The shoulder has three axes, there's one at the elbow, another in the lower arm and two more in the wrist. A rotary vane with two air chambers has been positioned at each axis, with compressed air allowing for mechanical spring-like adjustment.
Based on an elephant's trunk and the tentacles of an octopus, and a furthering of the work undertaken in 2010 on the Bionic Handling Assistant, the buzz words for the BionicMotionRobot are sensitive, gentle, powerful and dynamic. The arm is made up of three flexible segments that allow it to bend in three different directions at the same time.
Each segment is moved by pneumatic bellows according to instructions programmed into the Motion Terminal, with an optical sensor running through the center of the arm recording overall shape and position. Twelve elastomer bellows are covered with a 3D textile knitted fabric that's reported to allow the structures to expand in one direction while limiting movement in another.
The Future Concepts exhibits will be on show at Festo's booth at the Hannover Messe trade fair next month. The video below shows the OctopusGripper in action.
In 2015, Lockheed Martin took the wraps off a 30-kW mobile laser weapon that was powerful enough to take out a truck. Now the company will deliver a new 60-kW weapon to the US Army that earlier this month set a new record by generating a single 58-kW beam. With all phases from demonstration to development completed, Lockheed will ship the combined fiber laser to the US Army Space and Missile Defense Command/Army Forces Strategic Command in Huntsville, Alabama.
Similar to the previous laser, the new 60-kW design uses spectrum beam combining technology to produce a weapon-grade laser that is destructive as well as portable and accurate. The fiber laser modules are made of an active gain medium consisting of an optical fiber doped with a rare-earth element, including erbium, ytterbium, neodymium, or others.
The optical fibers are flexible, so the laser can be thousands of meters long for greater gain, while taking up very little space because it can be coiled like a rope. The large surface-to-volume ratio means that it's easy to cool. In addition, fiber lasers are very durable and project a high-quality beam using 50 percent less electricity than an equivalent solid-state laser.
Lockheed says that the individual lasers produced by the fibers are combined into a single beam that is intense and scalable through the addition of more fiber bundles. The present laser is close to the diffraction limit. That is, it's close to the physical limit for focusing a laser on a single spot without interfering with itself, but it's still highly efficient – translating over 43 percent of the electricity fed into it into laser light.
"The inherent scalability of this beam combined laser system has allowed us to build the first 60 kW-class fiber laser for the U.S. Army," says Robert Afzal, senior fellow for Laser and Sensor Systems. "We have shown that a powerful directed energy laser is now sufficiently light-weight, low volume and reliable enough to be deployed on tactical vehicles for defensive applications on land, at sea and in the air."
Lockheed sees the new lasers as eventually leading to new systems to provide protection against swarms of drones, rockets, and mortars that would overwhelm conventional defenses.
A new phase of matter, called a time crystal, has been created and observed for the first time. In a regular crystal, the atoms are arranged in a pattern that repeats itself across physical space, but in a time crystal, that pattern repeats through time instead. The possibility of their existence was first proposed in 2012, but they were deemed "forbidden" according to the laws of thermal equilibrium. The creation of time crystals marks one of the first steps into a new class of non-equilibrium phases.
MIT's Frank Wilczek first put forward the idea of a time crystal in 2012, inspired by the consideration that the repeating atomic structure of a crystal could be applied to time as well as space. Over the next few years, papers were published on both sides of the argument: some giving evidence for why they were impossible, while others suggested potential methods for making them. In 2016, a team from the University of California, Berkeley outlined how to create time crystals in a lab environment, and it's this technique that's finally borne fruit.
To illustrate the weirdness of time crystals, Norman Yao of the UC Berkeley team and this current study, used the example of tapping on a bowl of Jell-O. You'd expect it to respond instantly with a jiggle that slowly settles back down until it becomes still again, and the jiggling would only restart if you tap it again. Time crystals, on the other hand, react in ways that seem impossible to the casual observer: their atoms might "jiggle" after a delay, and then repeat the movement at regular intervals independent of the driving force.
"Wouldn't it be super weird if you jiggled the Jell-O and found that somehow it responded at a different period?" Yao explains, in a statement back in January. "But that is the essence of the time crystal. You have some periodic driver that has a period 'T', but the system somehow synchronizes so that you observe the system oscillating with a period that is larger than 'T'."
In most matter, hotter atoms will pass heat to adjacent cooler ones, until they all reach the same temperature. When that happens, the atoms settle into a state known as thermal equilibrium. But time crystals never reach that state, repeating the pattern of movement over time in an apparent display of perpetual motion. That makes them one of the first examples (if not the first) of non-equilibrium phases, a new type of matter.
"This opens the door to a whole new world of non-equilibrium phases," says Andrew Potter, one of the researchers on the study. "We've taken these theoretical ideas that we've been poking around for the last couple of years and actually built it in the laboratory. Hopefully, this is just the first example of these, with many more to come."
To create the time crystal, the researchers used ions of the element ytterbium. First, they levitated the ions electrically, then hit them with laser pulses that flipped them upside down. By blasting them regularly with lasers, the ions fell into a repeating pattern of flips.
That sounds pretty basic, but here's the kicker: the ions were only flipping once for every two laser pulses, meaning the pattern was operating on a time scale larger than the driving force. Strange as that sounds, it was the behavior the team expected, and helped to confirm that they had created a time crystal.
While it's hard to visualize a day-to-day application for this kind of discovery at this early stage, the researchers say that future non-equilibrium phases could be used in quantum computing, for storing or transmitting information.