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Cryostat-100 combines the best features of previous cryostats developed by NASA, while offering new features and conveniences. This unit can readily handle the full range of cryogenic-vacuum conditions over several orders of magnitude of heat flux. Guide rings, handling tools, and other design items make insulation change-out and test measurement verification highly reliable and efficient to operate. The new apparatus requires less ancillary equipment (it is not connected to storage tank, phase separator, subcooler, etc.) to operate properly. It is top-loading, which makes disassembly, change-out, and instrumentation hook-up much faster. The thermal stability is improved because of internal vapor plates, a single-tube system of filling and venting, bellows feed-throughs, Kevlar thread suspensions, and heavy-wall stainless-steel construction. The cold mass of Cryostat-100 is 1m long, with a diameter of 168 mm. The test articles can therefore be of a corresponding length and diameter, with a nominal thickness of 25.4 mm. Shorter lengths are acceptable, and thicknesses may be from 0 mm to 50 mm. Tests are conducted from ambient pressure (760 torr) to high vacuum (below 110-4 torr) and at any vacuum pressure increment between these two extremes. The residual gas (and purge gas) is typically nitrogen but can be any purge gas, such as helium, argon, or carbon dioxide. Typically, eight cold vacuum pressures are performed for each test series. The warm boundary temperature is approximately 293 K, and the cold boundary temperature is approximately 78 K. The delta temperature for the cryogenic testing is therefore approximately 215 K. A unique lift mechanism provides for change-out of the insulation test specimens. It also provides for maintenance and other operations in the most effective and time-efficient ways. The lift mechanism is also a key to the modularity of the overall system.

Advances in new polymers and composites along with growing industrial needs in below-ambient temperature applications have brought about the Macroflash development. Accurate thermal performance information, including effective thermal conductivity data, are needed under relevant end-use conditions. The Macroflash is a practical tool for basic testing of common materials or research evaluation of advanced materials/systems. The Macroflash can test solids, foams, or powders that are homogeneous or layered in composition. Test specimens are typically 75mm in diameter and 6mm in thickness. The cold side is maintained by liquid nitrogen at 77 K while a heater disk maintains a steady warm-side temperature from ambient up to 373 K. The steady boiloff of the liquid nitrogen provides a direct measure of the heat energy transferred through the thickness of the test specimen. Nitrogen or other gas is supplied to the instrument to establish a stable, moisture-free, ambient pressure environment. Different compression loading levels can also be conveniently applied to the test specimen as needed for accurate, field-representative thermal performance data. The Macroflash is calibrated from approximately 10 mW/m-K to 800 mW/m-K using well-characterized materials.

The technology utilizes four cutting-edge sensor technologies to enable minimally- or non-invasive analysis of various biological samples, including saliva, breath, and blood. The combination of technologies and sample pathways have unique advantages that collectively provides a powerful analytical capability. The four key technology components include the following: (1) the carbon nanotube (CNT) array designed for the detection of volatile molecules in exhaled breath; (2) a breath condenser surface to isolate nonvolatile breath compounds in exhaled breath; (3) the miniaturized differential mobility spectrometer (DMS) -like device for the detection of volatile and non-volatile molecules in condensed breath and saliva; and (4) the miniaturized circular disk (CD)-based centrifugal microfluidics device that can detect analytes in any liquid sample as well as perform blood cell counts. As an integrated system, the device has two ports for sample entry a mouthpiece for sampling of breath and a port for CD insertion. The breath analysis pathway consists of a CNT array followed by a condenser surface separating liquid and gas phase breath. The exhaled breath condensate is then analyzed via a DMS-like device and the separated gas breath can be analyzed by both CNT sensor array again and by DMS detectors.

Traditionally, unsteady pressure transducers have been the instrumentation of choice for investigating unsteady flow phenomena which can be time-consuming and expensive. The ability to measure and compute these flows has been a long-term challenge for aerospace vehicle designers and manufacturers. Results using only the pressure transducers are prone to inaccuracies, providing overly conservative load predictions in some cases and underestimating load predictions in other areas depending on the flow characteristics. NASA Ames has developed a new state-of-the-art method for measuring fluctuating aerodynamic-induced pressures on wind tunnel models using unsteady Pressure Sensitive Paint (uPSP). The technology couples recent advances in high-speed cameras, high-powered energy sources, and fast response pressure-sensitive paint. The unsteady pressure-sensitive paint (uPSP) technique has emerged as a powerful tool to measure flow, enabling time-resolved measurements of unsteady pressure fluctuations within a dense grid of spatial points on a wind tunnel model. The invention includes details surrounding uPSP processing. This technique enables time-resolved measurements of unsteady pressure fluctuations within a dense grid of spatial points representing the wind tunnel model. Since uPSP is applied by a spray gun, it is continuously distributed. With this approach, if the model geometry can be painted, viewed from a camera, and excited by a lamp source, uPSP data can be collected. Unsteady PSP (uPSP) has the ability to determine more accurate integrated unsteady loads.

Originally developed to demonstrate a highly accurate, low-false-alarm, early fire detection system in space, this advanced technology level system utilizes a durable, low-cost, compact laser source and detector array, similar to CD/DVD player technology, to analyze the interaction of light with particles. The smart system is ideal for detecting a diverse range of particles found in pollution, emissions, fire and other atmospheric toxins while introducing a flexibility that enables its use in multiple environments, especially when coupled with UAVs or other remote platforms. The MPASS contains a number of features that allow users to make the most of its pioneering capabilities. The self-contained system is lightweight and has been miniaturized and packaged to easily fit into the palm of your hand. A USB port enables the system to be powered, configured, and accessed through its onboard central processing unit. The advanced graphical user interface, custom software, and optimized algorithm allows the user to select known properties when applicable, and to program the system for maximum performance. The dashboard also provides visual feedback through graphical displays, making it easy to analyze the data and make real-time decisions. The system is designed with Bluetooth expansion capability, adding flexibility and communication through potential custom cellular phone applications. Once programmed, the battery-powered wireless sensor system opens the door to monitoring remote areas and extreme environments never thought possible.

High-temperature sensors have been used in silicon carbide electronic oscillator circuits. The frequency of the oscillator changes as a function of changes in the sensor's parameters, such as pressure. This change is analogous to changes in the pitch of a person's voice. The output of this oscillator, and many others may be superimposed onto a single medium. This medium may be the power lines supplying current to the sensors, a third wire dedicated to data transmission, the airwaves through radio transmission, or an optical or other medium. However, with nothing to distinguish the identities of each source, this system is useless. Using frequency dividers and linear feedback shift registers, comprised of flip flops and combinatorial logic gates connected to each oscillator, unique bit stream codes may be generated. These unique codes are used to amplitude modulate the output of the sensor (both amplitude shift keying and on-off keying are applicable). By using a dividend of the oscillator frequency to generate the code, a constant a priori number of oscillator cycles will define each bit. At the receiver, a detected frequency will have associated with it a stored code pattern. Thus, a detected frequency will have a unique modulation pattern or "voice," disassociating it from noise and from other transmitting sensors. These codes may be pseudorandom binary sequences (PRBS), ASCII characters, gold codes, etc. The detected code length and frequency are measured, offering intelligent data transfer. This is an early-stage technology requiring additional development. Glenn welcomes co-development opportunities.

One unique characteristic of this innovation is that it effects the measurement of I-V curves without the use of large resistor arrays or active current sources normally used to characterize cells. A single transistor is used as a variable resistive load across the cell. This multi-measurement instrument was constructed using operational amplifiers, analog switches, voltage regulators, metaloxidesemiconductor field-effect transistors (MOSFETs), resistors, and capacitors. The operational amplifiers, analog switches, and voltage regulators are silicon-on-insulator (SOI) technology known for its hardness to the effects of ionizing radiation. The SOI components used can tolerate temperatures up to 225°C, which gives plenty of thermal headroom allowing this circuit to perhaps reside in the solar cell panel itself where temperatures can reach over 100°C.

The PLGRM system is designed for in-situ antenna measurements at a remote site. Components include a collaborative (i.e., certified to operate in close proximity with humans) robot arm mounted on a vertical lift and a laser tracker, each on a mobile base. Together, these components enable scanning of a surface larger than the reach of the robot. To accomplish this, the robot first collects all points within its reach, then the system is moved and the laser tracker is used to relocate the robot before additional points are captured. Safety, collision avoidance, and planning aspects are combined to effectively characterize such antennas. Software-defined triggering is also a feature for flexible integration of network analyzers and antenna controllers. Laser tracking is used over photogrammetry to provide position feedback with higher speed and lower latency that facilitates online control of the robotic arm. While collecting the antenna radiation data, the system uses pulsed measurements and time gating to remove unwanted reflections. This lowers the requirement for fully surrounding the test area in anechoic foam. The system also accommodates the possibility of "dirty power" that may be found at any given host facility. NASA has published data that demonstrate system functionality and accuracy. See the PLGRM presentation and paper from the 2019 Antenna Measurement Techniques Association Symposium (AMTA) for more details on component choices, portability challenges, implementation, and measurement data.

This new version of the card assembly will feature a total of eight 4x DDR2 SDRAM memories per Xilinx FPGA. A dedicated regulator was included to compensate for the lower operating voltage of DDR2 in comparison to the older DDR memory. The DDR2 memories are grouped in pairs with shared address/command/control lines. By sharing those lines, the number of Xilinx I/O’s for the DDR2 interfaces could be reduced. These improvements extend the life and design of the processor and provide even greater memory throughput to support the next generation of instruments.