DEVELOPMENT AND TESTING OF A SENSOR ROD FOR CHEMICAL AND PHYSICAL MEASUREMENTS IN A TAI
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Jones, Daniel↗
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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Photon counting from the vacuum ultraviolet to the short wavelength infrared using semiconductor and superconducting technologies
In the last decade, several photon counting technologies have been developed opening a new window for experiments in the low photon number regime. Several ongoing and future projects in HEP benefit from these developments, which will also have a large impact outside HEP. During the next decade there is a clear technological opportunity to fully develop these sensors and produce a large impact in HEP. In this white paper we discuss the need for photon counting technologies in future projects, and present some technological opportunities to address those needs.
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
Development of a Distributed Optical Sensor Array for Improved Subsurface Characterization and Monitoring
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02 PETROLEUM↗
An Overview in the Development of a Multi-Sensor Data Science System for Monitoring a Solvent Extraction Process
To enhance nuclear nonproliferation stewardship, Idaho National Laboratory is building the Beartooth nuclear fuel cycle processing test bed. The Beartooth test bed will allow researchers the opportunity to study nuclear fuel processing operations including the use of centrifugal contactors in solvent extraction processes. The test bed is designed to support data collection and machine learning to monitor process operations. As part of this project, researchers will study data collected from a host of sensors that have not been typically used to monitor solvent extraction processes such as vibration, acoustic, colormetric, and thermal measurement data. The goal of this research is to employ machine learning and data analytics to study the confluence of signals collected from both traditionally and non-traditionally used sensors to provide operator process awareness and discover process anomalies. An overview of planned sensors and experiments that will focus on signal discovery will be presented.
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
An Overview in the Development of a Multi-Sensor Data Science System for Monitoring a Solvent Extraction Process
To enhance nuclear nonproliferation stewardship, Idaho National Laboratory is building the Beartooth nuclear fuel cycle processing test bed. The Beartooth test bed will allow researchers the opportunity to study nuclear fuel processing operations including the use of centrifugal contactors in solvent extraction processes. The test bed is designed to support data collection and machine learning to monitor process operations. As part of this project, researchers will study data collected from a host of sensors that have not been typically used to monitor solvent extraction processes such as vibration, acoustic, colormetric, and thermal measurement data. The goal of this research is to employ machine learning and data analytics to study the confluence of signals collected from both traditionally and non-traditionally used sensors to provide operator process awareness and discover process anomalies. An overview of planned sensors and experiments that will focus on signal discovery will be presented.
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
Development of Optical Emission Spectroscopy Sensors for Hypersonic Flight Applications
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Plumadore, Alexander Dean [Sandia National Laborat↗
Damage Characterization Method for Structural Health Management Using Reduced Number of Sensor Inputs
The development of validated multidisciplinary Integrated Vehicle Health Management (IVHM) tools, technologies, and techniques to enable detection, diagnosis, prognosis, and mitigation in the presence of adverse conditions during flight will provide effective solutions to deal with safety related challenges facing next generation aircraft. The adverse conditions include loss of control caused by environmental factors, actuator and sensor faults or failures, and damage conditions. A major concern in these structures is the growth of undetected damage (cracks) due to fatigue and low velocity foreign impacts that can reach a critical size during flight, resulting in loss of control of the aircraft. Hence, development of efficient methodologies to determine the presence, location, and severity of damage in critical structural components is highly important in developing efficient structural health management systems.
Krishnamurthy, T.↗
NREL Hydrogen Sensor Testing Laboratory
The NREL Sensor Laboratory supports the HFTO's mission for the safe and efficient implementation of hydrogen as an energy carrier. Sensors are a critical element for a facility safety system by providing an early indication of unintended releases. Sensors can be used in process control applications (e.g., FQ verification). The Sensor Laboratory provides developers and end-users with an unbiased resource to validate sensor performance to application requirements. The Sensor Laboratory facilitates deployment through support of codes and standards development and safety research. The Sensor Laboratory supports advanced strategies for early leak detection.
detection↗
Video guidance sensor for autonomous capture
A video-based sensor has been developed specifically for the close-range maneuvering required in the last phase of autonomous rendezvous and capture. The system is a combination of target and sensor, with the target being a modified version of the standard target used by the astronauts with the Remote Manipulator System (RMS). The system, as currently configured, works well for autonomous docking maneuvers from approximately forty feet in to soft-docking and capture. The sensor was developed specifically to track and calculate its position and attitude relative to a target consisting of three retro-reflective spots, equally spaced, with the center spot being on a pole. This target configuration was chosen for its sensitivity to small amounts of relative pitch and yaw and because it could be used with a small modification to the standard RMS target already in use by NASA.
Howard, Richard T.↗
A commercialized, continuous flow fiber optic sensor for trichloroethylene and haloforms
Purus, Inc. has commercialized a fiber optic chemical sensor using technology developed by Lawrence Livermore National Laboratory and licensed from The University of California. The basis for the sensor is the development of color within a reagent when exposed to an analyte. The sensor consists of an optrode, reagent delivery and recover system, fiber optic transmitter-receiver, controller, and display. Reagent is pumped through the optrode. Analyte diffuses across a gas permeable membrane and reacts with the reagent to form a colored product. The colored product is detected by measuring the absorbance of light from a 568 nm diode. Reagents are currently available for TCE and trihalomethanes. Initial reagent chemistry is based on the Fujiwara alkaline pyridine reaction. The optrode contacts only gas streams, but the volatility of the current analytes also allows measurements of aqueous streams, without being affected by aqueous interferents that are non-volatile. Sensitivity of the sensor has been demonstrated to 5 ppb aqueous solutions and 0.1 ppmv in flowing gas streams.
Wells, James C.↗
Sensor Selection and Data Validation for Reliable Integrated System Health Management
For new access to space systems with challenging mission requirements, effective implementation of integrated system health management (ISHM) must be available early in the program to support the design of systems that are safe, reliable, highly autonomous. Early ISHM availability is also needed to promote design for affordable operations; increased knowledge of functional health provided by ISHM supports construction of more efficient operations infrastructure. Lack of early ISHM inclusion in the system design process could result in retrofitting health management systems to augment and expand operational and safety requirements; thereby increasing program cost and risk due to increased instrumentation and computational complexity. Having the right sensors generating the required data to perform condition assessment, such as fault detection and isolation, with a high degree of confidence is critical to reliable operation of ISHM. Also, the data being generated by the sensors needs to be qualified to ensure that the assessments made by the ISHM is not based on faulty data. NASA Glenn Research Center has been developing technologies for sensor selection and data validation as part of the FDDR (Fault Detection, Diagnosis, and Response) element of the Upper Stage project of the Ares 1 launch vehicle development. This presentation will provide an overview of the GRC approach to sensor selection and data quality validation and will present recent results from applications that are representative of the complexity of propulsion systems for access to space vehicles. A brief overview of the sensor selection and data quality validation approaches is provided below. The NASA GRC developed Systematic Sensor Selection Strategy (S4) is a model-based procedure for systematically and quantitatively selecting an optimal sensor suite to provide overall health assessment of a host system. S4 can be logically partitioned into three major subdivisions: the knowledge base, the down-select iteration, and the final selection analysis. The knowledge base required for productive use of S4 consists of system design information and heritage experience together with a focus on components with health implications. The sensor suite down-selection is an iterative process for identifying a group of sensors that provide good fault detection and isolation for targeted fault scenarios. In the final selection analysis, a statistical evaluation algorithm provides the final robustness test for each down-selected sensor suite. NASA GRC has developed an approach to sensor data qualification that applies empirical relationships, threshold detection techniques, and Bayesian belief theory to a network of sensors related by physics (i.e., analytical redundancy) in order to identify the failure of a given sensor within the network. This data quality validation approach extends the state-of-the-art, from red-lines and reasonableness checks that flag a sensor after it fails, to include analytical redundancy-based methods that can identify a sensor in the process of failing. The focus of this effort is on understanding the proper application of analytical redundancy-based data qualification methods for onboard use in monitoring Upper Stage sensors.
Garg, Sanjay↗
Fiber-optic sensors for aerospace electrical measurements: An update
Fiber-optic sensors are being developed for electrical current, voltage, and power measurements in aerospace applications. These sensors are presently designed to cover ac frequencies from 60 Hz to 20 kHz. The current sensor, based on the Faraday effect in optical fiber, is in advanced development after some initial testing. Concentration is on packaging methods and ways to maintain consistent sensitivity with changes in temperature. The voltage sensor, utilizing the Pockels effect in a crystal, has excelled in temperature tests. This paper reports on the development of these sensors, the results of evaluation, improvements now in progress, and the future direction of the work.
Patterson, Richard L.↗
Chemiresistor sensor based on ion-imprinted polymer (IIP)-functionalized rGO for Cd(II) ions in water
This study reports the design and development of a novel chemiresistor (CR) sensor using ion imprinted polymer (IIP)-functionalized reduced graphene oxide (rGO) [IIP/rGO-CR] for cadmium ions (Cd(II)) determination in water. The sensor consisted of a CR transducer made of rGO channel bridging source and drain electrodes prepared by self-assembly and thermal reduction of graphene oxide (GO) on Au interdigitated electrodes chip fabricated on Si/SiO 2 substrate. The IIP was then grafted on rGO using surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization with polyethylenimine (PEI) and methylacrylic acid (MAA) as dual functional monomers and Cd(II) ions as template through UV light-initiated copolymerization. The IIP functionalized on rGO acted as an effective recognition element that modulated the resistance of rGO-CR upon binding of Cd(II), enabling Cd(II) detection at ppb level in aqueous solutions. The prepared IIP/rGO-CR sensor worked effectively in the linear range of 2~200ppb and achieved a limit of detection (LOD) of 0.83 ppb, which is lower than the World Health Organization guidelines of 3ppb for drinking water quality. The developed sensor of IIP/rGO-CR showed a high selectivity against a variety of trace and heavy metal ions found in water and good stability for up to 60 days when stored at room temperature for Cd(II) determination in water. Further, the sensor was successfully applied to analyzing Cd(II) spiked in tap, lake and river waters with a 94.5%–113.5% recovery, demonstrating a high degree of accuracy even in complex water samples. Finally, our results illustrated that the CR sensor of IIP functionalized rGO provides a potential platform for sensitive, robust and low-cost environmental analysis of Cd(II) in water.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Employing Automated Experimental Evolution to Understand Survival Strategies of Lab-Grown Extremophiles
Experimental evolution (EE) exposes microbes to intentional stressors to improve resistance through artificial mutation. The resulting changes to metabolic pathways, protein structure, and genetic sequences, along with traditional genetic engineering tools, to can help understand the mechanisms of improved tolerance. An automated experimental set-up -- the Automated Adaptive Directed Evolution Chamber (AADEC) -- with minimal scope for human interference was developed at NASA Ames. A second- generation device integrating more real-time biochemical sensors has been developed recently. Added sensors include pH for indicating metabolic products, oxidation-reduction potential (ORP) for indicating available/consumed metabolic energy, dissolved oxygen (DO) for indicating aerobic/anaerobic growth cycles, and electrical conductivity (EC) as an additional indicator of metabolic products. With four additional sensors, the system is biochemically more informative in real-time. More importantly, each sensor parameter can be used as a selection pressure, individually or in combination with others, to artificially create and control inhospitable environments analogous to extremophile habitats for microbial growth in the lab. Potential stressors to be added in the future include thermal, reactive oxygen species, metal-ion concentrations, and varying nutrient availability.
Automated↗
Virtual Pressure Sensor for Electronic Expansion Valve Control in a Vapor Compression Refrigeration System
Virtual sensor technology, which uses simulation models/algorithms to calculate a value to represent an unmeasured variable or replace a directly measured reading, has attracted many studies in the heating, ventilation, air conditioning and refrigeration (HVAC&R) industry. However, most virtual sensor technologies are developed for fault detection and diagnostics (FDD) purposes, which generally compare the virtual sensor values with actual measured values to detect if any fault occurred and identify the causes that led to the fault. It is rare to see studies focus on control performance of virtual sensors after substituting an actual sensor. This is particularly important for the system with no redundant sensor since a virtual sensor is the most effective way to operate the system in the desirable region when any sensor failure occurs. To address this gap, this paper develops a new virtual pressure sensor technology to substitute the actual pressure measurement for electronic expansion valve (EXV) control in a vapor compression refrigeration system by integrating compressor and valve characteristics. The control performance of this proposed virtual pressure sensor technology under various operating conditions is validated with experimental data. Closed loop EXV control simulations with the proposed virtual pressure sensor are conducted, and the results are analyzed.
47 OTHER INSTRUMENTATION↗
An arrayed hot-film sensor for detection of laminar boundary-layer flow disturbance spatial characteristics
An arrayed hot-film sensor has been developed for use in laminar boundary-layer research for the detection of crossflow or Goertler vortices. This sensor has been developed to detect spatial variations in heat transfer which are characteristic of crossflow or Goertler vortices. The sensor is ultimately intended for flight research applications. This paper describes the sensor, its priciples of operation, signal analysis techniques, and experimental results illustrating the spatial detection capabilities of this specialized hot-film device. Discretely placed spheres placed in the boundary layer created alternating regions of undisturbed and disturbed laminar flow over a prototype sensor. Flow visualization results were correlated with the sensor output to demonstrate the ability of the sensor to determine the spatial boundaries of localized disturbances in laminar flow. This work represents the initial steps toward the validation and calibration of an arrayed hot-film sensor for the detection of crossflow or Goertler vorticity wavelength and/or wave frequency.
Wusk, M. S.↗
Sensor and Actuator Needs for More Intelligent Gas Turbine Engines
This paper provides an overview of the controls and diagnostics technologies, that are seen as critical for more intelligent gas turbine engines (GTE), with an emphasis on the sensor and actuator technologies that need to be developed for the controls and diagnostics implementation. The objective of the paper is to help the "Customers" of advanced technologies, defense acquisition and aerospace research agencies, understand the state-of-the-art of intelligent GTE technologies, and help the "Researchers" and "Technology Developers" for GTE sensors and actuators identify what technologies need to be developed to enable the "Intelligent GTE" concepts and focus their research efforts on closing the technology gap. To keep the effort manageable, the focus of the paper is on "On-Board Intelligence" to enable safe and efficient operation of the engine over its life time, with an emphasis on gas path performance
Garg, Sanjay↗
Retrieval of water vapor mixing ratios from a laser-based sensor
Langley Research Center has developed a novel external path sensor which monitors water vapor along an optical path between an airplane window and reflective material on the plane's engine. An infrared tunable diode laser is wavelength modulated across a water vapor absorption line at a frequency f. The 2f and DC signals are measured by a detector mounted adjacent to the laser. The 2f/DC ratio depends on the amount of wavelength modulation, the water vapor absorption line being observed, and the temperature, pressure, and water vapor content of the atmosphere. The present work concerns efforts to quantify the contributions of these factors and to derive a method for extracting the water vapor mixing ratio from the measurements. A 3 m cell was fabricated in order to perform laboratory tests of the sensor. Measurements of 2f/DC were made for a series of pressures and modulation amplitudes. During my 1994 faculty fellowship, a computer program was created which allowed 2f/DC to be calculated for any combination of the variables which effect it. This code was used to generate 2f/DC values for the conditions measured in the laboratory. The experimental and theoretical values agreed to within a few percent. As a result, the laser modulation amplitude can now be set in the field by comparing the response of the instrument to the calculated response as a function of modulation amplitude. Once the validity of the computer code was established, it was used to investigate possible candidate absorption lines. 2f/DC values were calculated for pressures, temperatures, and water vapor mixing ratios expected to be encountered in future missions. The results have been incorporated into a database which will be used to select the best line for a particular mission. The database will also be used to select a retrieval technique. For examples under some circumstances there is little temperature dependence in 2f/DC so temperature can be neglected. In other cases, there is a dependence with temperature for a particular pressure, requiring a more complicated retrieval algorithm. Future experimental work is necessary to test agreement with the theoretical values over a range of temperatures and mixing ratios. Additionally, retrieval algorithms for forthcoming missions must be incorporated into the software package which controls the instrument.
Tucker, George F.↗