electrical and electronics
Double Sided Si(Ge)/Sapphire/III-Nitride Hybrid Structures
III-nitride devices are commonly made on sapphire substrates today for various commercial electronic and optoelectronic applications. Thus, this innovation relates directly to the combination of devices on opposite sides of the sapphire substrate. One possible device combination is to have LEDs one side and solar cells on the other, such as for displays.
information technology and software
The Estimated Spectrum Adaptive Postfilter (ESAP)
ESAP looks into the decoded JPEG image and determines the location of the edges of the image. An edge is the spatial transition from lets say, a human face to a landscape background or the silhouette or cartoon of a person or object. In the areas away of the edges, ESAP performs adaptive filtering to remove the pixelation (or blocking artifacts) created by highly compressed JPEG images. In general, ESAP improves both, the subjective visual quality of highly compressed JPEG images, as well as their objective quality measure known as the Peak-Signal-to-Noise Ratio (PSNR), as compared to baseline JPEG images. It does this without requiring any additional overhead in the data stream.
mechanical and fluid systems
Micro scale electro hydrodynamic (EHD) modular cartridge pump
NASA GSFCs EHD pump uses electric fields to move a dielectric fluid coolant in a thermal loop to dissipate heat generated by electrical components with a low power system. The pump has only a few key components and no moving parts, increasing the simplicity and robustness of the system. In addition, the lightweight pump consumes very little power during operation and is modular in nature. The pump design takes a modular approach to the pumping sections by means of an electrically insulating cartridge casing that houses the high voltage and ground electrodes along with spacers that act as both an insulator and flow channel for the dielectric fluid. The external electrical connections are accomplished by means of commercially available pin and jack assemblies that are configurable for a variety of application interfaces. It can be sized to work with small electric components or lab-on-a-chip devices and multiple pumps can be placed in line for pumping greater distances or used as a feeder system for smaller downstream pumps. All this is done as a one-piece construction consolidating an assembly of 21 components over previous iterations.
information technology and software
Reconfigurable Image Generator and Database Generation System
The system, the Reconfigurable Image Generator (RIG), consists of software and a hardware configuration, and a Synthetic Environment Database Generation System (RIG-DBGS). This innovative Image Generator (IG) uses Commercial-Off-The-Shelf (COTS) technologies and is capable of supporting virtually any display system. The DBGS software leverages high-fidelity real-world data, including aerial imagery, elevation datasets, and vector data. Through a combination of COTS tools and in-house created applications, the semi-automated system can process large amounts of data in days rather than weeks or months, a disadvantage of manual database generation. A major benefit of the RIG technology is that existing simulation users can leverage their investment in existing real-time 3D databases (such as OpenFlight) as part of the RIG system.
Digitally Synthesized Phased-Array Antenna
JPL's phased-array antenna system comprises a phased-array antenna and a set of parallel digital signal processing channels containing analog-to-digital converters. During operation, the beam direction of the array is steered to a selected satellite by introducing a uniform difference between the phases of the outputs of adjacent antennas in the array. The phase-delay elements are digitally synthesized within each of the signal processing channels. Early, prompt, and late correlation functions for the selected satellite can be combined in phase from each of the antennas. All of the digital operations of these signal processing channels can be implemented in a single microprocessor, and a corrective feedback loop can be used to fine-tune to phase delay between adjacent antenna elements to maximize the arrayed signal. This phased-array antenna system can be used in applications where the satellite positions are unknown. The satellite selection circuit can randomly slew the phase-angle difference through a continuum of values while monitoring the corrective feedback loop to maximize the correlation function. The system can also be used in applications where the spacing between the arrayed antennas is non-uniform or the antennas lie on a curved surface. Such variations can be accommodated by providing a proportionately different phase multiplication factor for each of the antennas.
Process for fabricating superconducting circuitry on both sides of an ultra-thin silicon (Si) layer.
This fabrication method allows for a minimalistic silicon wafer to be used as a circuit board while reducing space and increasing efficiency by depositing superconducting material on both sides. Due to the thin nature of the silicon wafer, an additional backing handle wafer is required during the fabrication of this circuitry to allow for deposition of metal thin film on a hot substrate on one side of the wafer. In addition, a metallic and polymeric sacrificial layer is used to protect the silicon substrate and superconducting metallic layers during removal of the unwanted silicon, buried oxide, and epoxy layers. This process introduces the fabrication methodology required to realize the ultra-low loss transmission lines and ultra-low crosstalk between superconducting sensors.
power generation and storage
Compliant electrode and composite materials for piezoelectric wind and mechanical energy conversions
The NASA researchers integrated two innovations into this unique piezoelectric device. First, they combined polyvinylidene flouride (PVDF) with a metal oxide to improve conductance. Second, they designed a new carbon-electrode to improve durability (compliance) and reduce susceptibility to fatigue while retaining flexibility. Additionally, to integrate the carbon nanotube components, they use a polymer-to-polymer design that eliminates the need for adhesion layers. A prototype device generated 1 W power (at 15 mph wind) with a single layer of PVDF [4 inch by 12 inch and 50 um (micrometer) thick] sandwiched between two thin electrode films. A rectifier converts the AC signal into a DC signal and stores the charge in a capacitor. This electric power can be used for low power consuming devices, such an inaccessible sensors.
Variable Visibility Glasses for Instrument Flight Training
The technology combines electroactively controlled liquid crystal lenses with a means for determining the pilots head position. When the pilots head is positioned to look outside the front or side windscreens, the lenses restrict light transmission. When the pilots head is lowered to view the instrument panel or other cockpit displays, the lenses allow light transmission so that the view of the instruments is unimpeded. Light transmission through the lenses can be selectively controlled by the system, ranging from 0.1% to 10%. The lenses are mounted in conventional eyeglass frames. The frames include a detection system to determine the position and orientation of the pilots head. Circuits within the frames activate the lenses to restrict light transmission when the pilots head is oriented to look out the windscreen. A PC, linked to the aircraft flight computer or altimeter, is also in the control loop and turns off the system to allow unimpeded visibility when the aircraft is below 200 feet or for other specified conditions. The technology readiness level of this invention is at stage seven with a prototype having been tested.
Accelerometer and Gyroscope Designs Based on CNT Tape
NASA's accelerometer was designed to address the shortcomings of conventional piezoelectric-based accelerometers that are made from ceramic materials such as barium titanate (BaTiO3) or lead titanate (PZT). These materials are inherently brittle, have a tendency to be noisy, have difficulty sensing low frequencies, are subject to static charge build-up that affects polarization, and are relatively large and expensive. The unique feature of the NASA innovation is the use of carbon nanotube/P(VDF-TrFE) tape as the actuating and sensing element. As seen in the figure to the right, the new accelerometer acts as a spring-mass system. There is a moving mass (M) between fixed walls and attached to two CNT tapes on both sides. The mass will be displaced by u(t) along a single axis when an applied force, F(t), acts on the mass. This sensor uses one tape as an actuator to damp motion of the moving mass, while the other tape is used for sensing the mass displacement. The figure below left is a photo of the CNT tape being poled. The single axis accelerometer can be used solo or as the basis for a novel two-axis gyroscope. The CNT tape is used as the vibrating element in the gyroscope. The NASA gyroscope design covers three configurations: 1. CNT tape wrapped around the conductive rotor of the gyroscope 2. The same CNT tape layered with piezo material to form a rotor shape 3. Piezo-sprayed CNT tape used as a rotor The figure to the right is a stress vs. strain curve for the CNT tape that is used in the gyroscope and accelerometer.
mechanical and fluid systems
Feedthrough for Severe Environments and Temperatures
Space and ground launch support related hardware often operate under extreme pressure, temperature, and corrosive conditions. When dealing with this type of equipment, it is frequently necessary to run wiring, tubes, or fibers through a barrier separating one process from another with one or both operating in extreme environments. Feedthroughs used to route the wiring, tubes, or fibers through these barriers must meet stringent sealing and leak tightness requirements. This affordable NASA feedthrough meets or exceeds all sealing and leak requirements utilizing easy-to-assemble commercial-off-the-shelf hardware with no special tooling. The feedthrough is a fully reconfigurable design; however, it can also be produced as a permanent device. Thermal cycling and helium mass spectrometer leak testing under extreme conditions of full cryogenic temperatures and high vacuum have proven the sealing capability of this feedthrough with or without potting (epoxy fill) on the ends. Packing material disks used in the construction of the device can be replaced as needed for rebuilding a given feedthrough for another job or a different set of feeds if potting is not used for the original feedthrough build. (Potting on one or both sides of the sleeve provides double or triple leak sealing protection). Variable Compression Ratio (VCR) connectors were adapted for the pressure seal on the feedthrough; however, any commercial connector can be similarly adapted. The design can easily be scaled up to larger (2" diameter) and even very large (12" or more) sizes.