Manufacturing Bits: Aug. 21
Mars Rover Shoots Laser
So far, NASA is basking in the sun over its current and successful mission to Mars. NASA’s rover, dubbed Curiosity, landed on Mars two weeks ago, beginning a two-year mission on the red planet.
In its latest experiment, Curiosity fired its on-board laser for the first time on Mars. The laser is designed to analyze the elements of a small rock on the surface called “Coronation.” The entire laser-based system is called the Chemistry and Camera instrument or ChemCam.
ChemCam generates a pulsed laser delivering at least 10 megawatts per square millimeter to the target. The atoms are then ablated into excited states. The composition of the target can be determined by resolving the emission lines. A 1024 x 1024 pixel CCD will provide images of the targets within about 10 meters of the rover.
The technique used by ChemCam is called laser-induced breakdown spectroscopy. The technology has been used to determine composition of targets in other extreme environments. This includes inside nuclear reactors and on the sea floor. It has experimental applications in environmental monitoring and cancer detection.
ChemCam was developed by the U.S. Department of Energy’s Los Alamos National Laboratory in partnership with the French national space agency, Centre National d’Etudes Spatiales (CNES) and research agency, Centre National de la Recherche Scientifique (CNRS).
ALD Used For Spacecraft Components
NASA and the University of Maryland are using atomic layer deposition (ALD) to create a new class of strong materials made of boron-nitride nanotubes (BNNTs). BNNTs have a similar structure as carbon nanotubes. Crystalline boron nitride is one of the world’s hardest materials.
One of the goals is to devise materials to protect sensitive spacecraft components from high-velocity micrometeorites, solar particles, and space junk. These objects can move up to 12.4 miles (20 kilometers) per second, according to NASA.
Goddard technologist Vivek Dwivedi (right) and his collaborator, University of Maryland professor Raymond Adomaitis (left), are preparing to insert a sample inside a reactor that will apply a thin film using the atomic layer deposition technique. Source: NASA
Without ALD, researchers must manufacture boron films by reacting boron powder with nitrogen and a small amount of ammonia in a chamber that must be heated to 2,552 degrees Fahrenheit. With ALD, boron-nitride film could be made in a chamber no hotter than 752 degrees Fahrenheit, according to NASA.
In another application, ALD could be used to coat X-ray telescope mirrors. In a statement, Ted Swanson, assistant chief for technology for mechanical systems at NASA’s Goddard Space Flight Center, said: “This is an emerging technology that offers a wholly new way to protect spacecraft components, perhaps more effectively than what is possible with current techniques. Just as important, with ALD, we can lay down material less expensively.”
NASA Devises Spectrometer-On-A-Chip
The Composite Infrared Spectrometer (CIRS) is an instrument aboard NASA’s Cassini mission to Saturn. It measures the infrared energy from Saturn, its rings and its moons.
The CIRS is the size of a dishwasher, however. In the future, NASA hopes to devise a smaller, lighter and more capable system. In doing so, the U.S. space agency is developing a spectrometer-on-a-chip.
The device is a scaled down version of the Michelson-type Fourier Transform Spectrometer (FTS) used today. This system is used to study planets and stars and identify their chemical makeup.
In all, NASA hopes to replace the mirrors and associated hardware with a microscale photonic system. It would consist of 60 hollow waveguides at 10 times thinner than a human hair.
NASA plans to demonstrate the device by the end of the year, but a working chip is still years away. In a statement, Shahid Asalm, the principal investigator leading the effort funded by NASA’s Center Innovation Fund and Goddard’s Internal Research and Development program, said: “The result is a spectrometer-on-a-chip that fits in the palm of a hand, excludes moving parts, and samples the complete inteferogram simultaneously. In addition, the device does not require mechanical power to move the mirror, nor any bulky, high-precision free-space optics as in classical Fourier transform spectrometers. The significance of our research is that we’re transforming how we propagate light. We’re replacing large, high-precision optics with microscale light pipes.”
Tags: ALD, atomic layer deposition, boron-nitride nanotubes, composite infrared spectrometer, FTS, NASA, University of Maryland