Sensors/Data Acquisition

Pressure Sensor Using Piezoelectric Bending Resonators

This technology applies to any application in which high-pressure measurement is required. NASA’s Jet Propulsion Laboratory, Pasadena, California A pressure sensor was developed based on a piezoelectric bending resonator. The resonator is covered and mechanically coupled with a sealed enclosure. The impedance spectrum of the resonator changes with the deformation of the enclosure induced by pressure or force applied to the enclosure. The changes in the impedance can be mapped to exchanges in the external environment, and the shifts in the resonance can be used to track the pressure.

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Using a Ubiquitous Conductor to Power and Interrogate Wireless Passive Sensors and Construct a Sensor Network

Sensor nodes are used in health monitoring of aircraft and vehicles, building monitoring, human activity monitoring, and information collection for fire and disaster rescue. Langley Research Center, Hampton, Virginia Many methods have been developed for interrogation of wireless passive sensors. Surface acoustic wave (SAW) sensors and RF reflection sensors can receive and reflect electronic magnetic waves that are broadcast and received by the antennas. The interrogation distance can range from several meters to tens of meters. These previously developed technologies have limitations. The signal frequency is very high (usually at GHz level), which increases the difficulties in signal processing and interrogation system development, and the interrogation distance is limited by the power attenuation in the space. Longer interrogation distance requires higher-power-density electromagnetic (EM) waves in signal broadcasting, which increases the EMI hazard to environments.

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Full-Field Inverse Finite Element Method for Deformed Shape- and Stress-Sensing of Plate and Shell Structures

Real-time reconstruction of full-field structural displacements helps provide feedback to the actuation and control systems of aerospace vehicles with morphed-wing architecture. Langley Research Center, Hampton, Virginia Structural health management systems that, by way of real-time monitoring, help mitigate accidents due to structural failures, will become integral technologies of the next-generation aerospace vehicles. Advanced sensor arrays and signal processing technologies are utilized to provide optimally distributed in-situ sensor information related to the states of strain, temperature, and aerodynamic pressure. To process the massive quantities of measured data, and to infer physically admissible structural behavior, requires robust and computationally efficient physics-based algorithms.

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Pressure-Optimized Optical Breath Gas Analyzer for Portable Life Support Systems

This instrument could be used in trace gas sensor applications where rapid sampling in a compact package is required, such as in human-occupied closed volumes. Lyndon B. Johnson Space Center, Houston, Texas Optical detection of gaseous carbon dioxide, water vapor (humidity), and oxygen is desired in Portable Life Support Systems (PLSS) incorporating state-of-the-art CO2 scrubbing architectures. Earlier broadband detectors are nearing their end of life, and recent advances in laser diode technology make replacement of earlier technology compelling. The function of the infrared gas transducer used during extravehicular activity (EVA) in the current spacesuit is to measure and report the concentration of CO2 in the ventilation loop. The next-generation PLSS requires next-generation CO2 sensing technology with performance beyond that presently in use on the Shuttle/International Space Station extravehicular mobility unit (EMU). Accommodation within spacesuits demands that optical sensors meet stringent size, weight, and power requirements. A sensor is required that is compact, low power, low mass, has rapid sampling capability, can operate over a wide pressure range, and can recover from condensing conditions.

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Lightweight Metal Rubber Textile Sensor for In-Situ Lunar Health Monitoring

This personnel status sensor can be used to measure, record, and communicate heart rate, electrocardiogram (ECG), and core body temperature information. Lyndon B. Johnson Space Center, Houston, Texas Extravehicular activities (EVAs) are dangerous to astronauts for a number of reasons, including high levels of physical exertion, potential for impacts by space debris particulates that could puncture the spacesuit and cause depressurization, Moon dust exposure that is abrasive and possibly biologically harmful, harsh thermal environments (extreme variation from –150 to >120 ºC when directly exposed to the Sun), and extreme low pressure (≈0 atm). These harsh environmental conditions inevitably lead to emotional pressure and stress, which directly impact physiological condition and potentially affect performance and safety. Because many EVA operations are time-consuming, astronauts may be extremely uncomfortable for several continuous hours.

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SEA5: Space Environment Automated Alerts & Anomaly Analysis Assistant

Goddard Space Flight Center, Greenbelt, Maryland The Community Coordinated Modeling Center (CCMC) provides a wide range of space weather tools and services for the general scientific community. One such product that facilitates space weather situational awareness is collectively known as the Integrated Space Weather Analysis (ISWA) System. Using the ISWA system and other tools, space weather forecasters are able to assess the space environment in both real time and for historical cases — both of which help mitigate potential space weather impacts on missions, as well as assist in spacecraft anomaly resolution. The Space Environment Automated Alerts & Anomaly Analysis Assistant (SEA5) will provide past, present, and predicted space environment information for specific missions, orbits, and user-specified locations throughout the heliosphere, geospace, and on the ground.

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Extensible Data Gateway Environment (EDGE)

NASA’s Jet Propulsion Laboratory, Pasadena, California The NASA Physical Oceanography Distributed Active Archive Center (PO.DAAC) is NASA’s designated data center for information relevant to the physical state of the ocean. Its core datamanagement and workflow system, Data Management and Archive System (DMAS), is responsible for processing hundreds of thousands of data products each day, around the clock. Its inventory captures over 800 datasets, several million granules, and millions of files. PO.DAAC is in need of a solution to help users quickly identify the relevant oceanographic data artifact. It also needs to export metadata according to the ISO-19115, FGDC, and GCMD specifications. Developing such a solution on top of its Oracle database has several issues. First, it is difficult to maintain since SQL needs to be updated when a schema changes or when new search criteria is needed. Second, multi-table joins yield poor performance. Third, query performance can be improved with additional indexes, but performance is negatively impacted on updates. Fourth, exposing the operational database as the direct backend to a publicly accessible service layer would subject Oracle to a Denial of Service (DoS) attack, which could halt the already very busy DMAS operation environment.

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