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3721.比色传感器和指示器的结构色
[计算机、通信和其他电子设备制造业] [2014-05-14]
Colourimetric sensors and indicators are widely used because of their low cost and simplicity. A significant challenge associated with the design of this type of device is that the sensing mechanism must be simultaneously optimised for the sensitivity of the response and a visually perceptible colour change. Structural colour, derived from coherent scattering rather than molecular absorption, is a promising route to colourimetric sensor design because colour shifts are tied to changes in one of many physical properties of a material, rather than a specific chemical process. This Feature Article presents an overview of the development of low-cost sensors and indicators that exploit structural colour. Building upon recent advances in structurally adaptive materials design, structural colour sensors have been developed for a wide variety of previously inaccessible physical (e.g. temperature, strain, electric fields) and chemical stimuli (e.g. small organic molecules, charged species, biomacromolecules and metabolites). These devices, often exceeding the state of the art in performance, simplicity or both, have bright prospects for market impact in areas such as environmental monitoring, workplace hazard identification, threat detection, and point-of-care diagnostics. Finding the ideal balance between performance (e.g. sensitivity, specificity, reproducibility, etc.) and simplicity (e.g. colourimetric vs. spectroscopic readout) will be one of the most critical elements in the further development of structural colour sensors. This balance should be driven largely by the market demands and competing technologies.
关键词:传感器;比色分析法;比色法;检测器
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3722.嵌入式传感器与控制以提高组件性能和可靠性。概念设计报告。
[计算机、通信和其他电子设备制造业] [2014-05-14]
This project, sponsored by the US Department of Energy (DOE) Nuclear Energy Enabling Technology (NEET) program, focuses on the development of advanced embedded sensors and controls to achieve significant performance, reliability, and safety improvements for nuclear reactor components and systems. As survivability and reliability are critical, designing and validating embedded measurement and control technologies in representative operating conditions are needed. With this framework in mind, a canned rotor pump platform is being constructed as a validation platform for advanced sensor and control development. The demonstration platform is a suitable application in advanced reactor designs that present challenging environments and operational demands. Consequently, the benefits from enhanced control system capabilities can be clearly assessed while the project outcome will also fulfill a need for improved technology to meet the goals of advanced reactor performance. Additionally, the complexity of the system is such that traditional control techniques are inadequate and more advanced techniques need to be utilized for the system to be feasible. The cost of nuclear energy is directly related to the cost and reliability of nuclear power plant (NPP) components. Deeply embedding instrumentation and controls (I&C) within these components has the potential to significantly increase the reliability of the components while enabling otherwise unobtainable performance and reduced maintenance cost. Directly measuring changes in component characteristics and performance can obviate a significant portion of component maintenance, which is both time-consuming and expensive in itself and, more importantly, lowers plant availability. Embedding I&C within components is key to observing degradation in the component and predicting remaining useful life.
关键词:传感器;控制系统;核反应堆安全;堆内构件
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3723.助记符UCS无线声表面波传感器系统的表征测试报告
[计算机、通信和其他电子设备制造业] [2014-05-14]
NASA's Kennedy Space Cenler (KSC) recently acquired two state-of-the-art wireless sensor systems as the final deli verable ora Phase " Small Business Technology Transfer (STIR) contract with Mnemonics, tnc. and the Uni versity of Central Florida (UCF), contract number NNX09CB69C. Mnemonics constnlcted the radio freq uency (RF) interrogator portion of these systems and UCF constructed the sensors, which arc based on a novel surface acoustic wave (SA W) arch itecture. The purpose of this testing is to characterize the performance of the system, both in its basic parameters and under a range of operat ing conditions.
关键词:传感器;信号探测器;声波;声表面波器件;变送器接收器
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3724.未知地形中基于雷达的导航
[计算机、通信和其他电子设备制造业] [2014-05-14]
There is a great need to develop non-GPS based methods for positioning and navigation in situations where GPS is not available. This research focuses on the development of an Ultra-Wideband Orthogonal Frequency Division Multiplexed (UWB-OFDM) radar as a navigation sensor in GPS-denied environments. A side-looking vehicle-fixed UWB-OFDM radar is mounted to a ground or aerial vehicle continously collecting data. A set of signal processing algorithms and methods are developed which use the raw radar data to aide in calculating the vehicle position and velocity via a simultaneous localization and mapping (SLAM) approach. The radar processing algorithms detect strong, persistent, and stationary reflectors embedded in the environment and extract range/Doppler measurements to them. If the radar is the only sensor available, the measurements are used to directly compute the vehicle position. If an existing navigation platform is available, the measurements are combined with the other sensors in an EKF. The developed algorithms are tested via both a series of airborne simulations and a ground- based experiment. The computed navigation solution performance is analyzed with the following sensor availability: radar-only, INS-only, and combined radar/INS. In both simulations and experimental scenarios, the integrated INS/UWB-OFDM system shows significant improvements over an INS-only navigation solution.
关键词:传感器;雷达导航;多普勒系统;全球定位系统
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3725.巷道环境感测系统的冻雨算法的开发和示范
[信息传输、软件和信息技术服务业] [2014-05-14]
The primary goal of this project is to demonstrate the accuracy and utility of a freezing drizzle algorithm that can be implemented on roadway environmental sensing systems (ESSs). The types of problems related to the occurrence of freezing precipitation range from simple traffic delays to major accidents that involve fatalities. Freezing drizzle can also lead to economic impacts in communities with lost work hours, vehicular damage, and downed power lines. There are means for transportation agencies to perform preventive and reactive treatments to roadways, but freezing drizzle can be difficult to forecast accurately or even detect as weather radar and surface observation networks poorly observe these conditions. The detection of freezing precipitation is problematic and requires special instrumentation and analysis. The Federal Aviation Administration (FAA) development of aircraft anti-icing and deicing technologies has led to the development of a freezing drizzle algorithm that utilizes air temperature data and a specialized sensor capable of detecting ice accretion. However, at present, roadway ESSs are not capable of reporting freezing drizzle. This study investigates the use of the methods developed for the FAA and the National Weather Service (NWS) within a roadway environment to detect the occurrence of freezing drizzle using a combination of icing detection equipment and available ESS sensors. The work performed in this study incorporated the algorithm developed initially and further modified for work with the FAA for aircraft icing. The freezing drizzle algorithm developed for the FAA was applied using data from standard roadway ESSs. The work performed in this study lays the foundation for addressing the central question of interest to winter maintenance professionals as to whether it is possible to use roadside freezing precipitation detection (e.g., icing detection) sensors to determine the occurrence of pavement icing during freezing precipitation events and the rates at which this occurs.
关键词:传感器;路维护支持;航空器;算法
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3726.重返航天器航天飞机轨道器的远距离观测
[计算机、通信和其他电子设备制造业] [2014-05-14]
Flight measurement is a critical phase in development, validation and certification processes of technologies destined for future civilian and military operational capabilities. This paper focuses on several recent NASA-sponsored remote observations that have provided unique engineering and scientific insights of reentry vehicle flight phenomenology and performance that could not necessarily be obtained with more traditional instrumentation methods such as onboard discrete surface sensors. The missions highlighted include multiple spatially-resolved infrared observations of the NASA Space Shuttle Orbiter during hypersonic reentry from 2009 to 2011, and emission spectroscopy of comparatively small-sized sample return capsules returning from exploration missions. Emphasis has been placed upon identifying the challenges associated with these remote sensing missions with focus on end-to-end aspects that include the initial science objective, selection of the appropriate imaging platform and instrumentation suite, target flight path analysis and acquisition strategy, pre-mission simulations to optimize sensor configuration, logistics and communications during the actual observation. Explored are collaborative opportunities and technology investments required to develop a next-generation quantitative imaging system (i.e., an intelligent sensor and platform) with greater capability, which could more affordably support cross cutting civilian and military flight test needs.
关键词:传感器;天飞机轨道器;成像技术;飞行试验
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3727.拉格朗日框架中纬度深对流系统的生命周期
[信息传输、软件和信息技术服务业] [2014-05-14]
Deep Convective Systems (DCSs) consist of intense convective cores (CC), large stratiform rain (SR) regions, and extensive non-precipitating anvil clouds (AC). This study focuses on the evolution of these three components and the factors that affect convective AC production. An automated satellite tracking method is used in conjunction with a recently developed multi-sensor hybrid classification to analyze the evolution of DCS structure in a Lagrangian framework over the central United States. Composite analysis from 4221 tracked DCSs during two warm seasons (May-August, 2010-2011) shows that maximum system size correlates with lifetime, and longer-lived DCSs have more extensive SR and AC. Maximum SR and AC area lag behind peak convective intensity and the lag increases linearly from approximately 1-hour for short-lived systems to more than 3-hours for long-lived ones. The increased lag, which depends on the convective environment, suggests that changes in the overall diabatic heating structure associated with the transition from CC to SR and AC could prolong the system lifetime by sustaining stratiform cloud development. Longer-lasting systems are associated with up to 60higher mid-tropospheric relative humidity and up to 40stronger middle to upper tropospheric wind shear. Regression analysis shows that the areal coverage of thick AC is strongly correlated with the size of CC, updraft strength, and SR area. Ambient upper tropospheric wind speed and wind shear also play an important role for convective AC production where for systems with large AC (radius greater than 120-km) they are 24and 20higher, respectively, than those with small AC (radius=20 km).
关键词:传感器;拉格朗日函数;回归分析;频率分布
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3728.埃琳ASIC中Prototupe探测器系统的直线加速器相干光源表征
[计算机、通信和其他电子设备制造业] [2014-05-14]
eLine, a class of multichannel time-variant integrating front-end Application Specific Integrated Circuits (ASICs), has been completed at SLAC National Accelerator Laboratory for applications at the Linac Coherent Light Source (LCLS). The class, designed for pixelated sensors with column parallel readout, is composed of two front-end ASICs: one designed for high-dynamic range applications (eLine10k) and one designed for ultra-low noise applications (eLine100). The first allows large input full-scale signals, on the order of 104 8keV photons, with a resolution of half a photon FWHM; while the second provides low noise charge integration, up to a full-scale signal of 100 8keV photons, with an equivalent noise charge (ENC) of 55e- r.m.s. Three different prototype systems utilizing the ASICs are described. The first is a 32k-pixel X-ray Active Matrix Pixel Sensor (XAMPS) detector developed at Brookhaven National Laboratory (BNL) for the X-ray Pump Probe instrument (XPP) at LCLS. The XAMPS are monolithic detectors with fast-frame readout and large full-scale signal. In particular, they provide a full well capacity on the order of 104 8keV photons per pixel and a resolution of half a photon FWHM. The second prototype, developed around eLine10k, is a beam finder with high dynamic range. The third prototype is developed around eLine100 to be used as detector in a spectrometer. Applications, test results and performance are discussed.
关键词:传感器;集成电路;探测器;直线加速器相干光源
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3729.表征轮静电光谱仪的性能
[计算机、通信和其他电子设备制造业] [2014-05-14]
A Wheel Electrostatic Spectrometer has been developed as a surveying tool to be incorporated into a planetary rover design. Electrostatic sensors with various protruding cover insulators are embedded into a prototype rover wheel. When these insulators come into contact with a surface, a charge develops on the cover insulator through tribocharging. A charge spectrum is created by analyzing the accumulated charge on each of the dissimilar cover insulators. We eventually intend to prove charge spectra can be used to determine differences in planetary regolith properties. We tested the effects of residual surface charge on the cover insulators and discovered a need to discharge the sensor cover insulators after each revolution. We proved the repeatability of the measurements for this sensor package and found that the sensor repeatability lies within one standard deviation of the noise in the signal.
关键词:传感器;静电学;光谱仪;绝缘子
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3730.平衡微机电系统(MEMS)力学和机械逻辑规模仿生导航传感器
[计算机、通信和其他电子设备制造业] [2014-05-13]
Small autonomous aerial systems require the ability to detect roll, pitch, and yaw to enable stable flight. Existing inertial measurement units (IMUs) are incapable of accurately measuring roll-pitch-yaw within the size, weight, and power requirements of small autonomous systems. To overcome this, we have designed novel IMUs based on the biological haltere system in a microelectromechanical system (MEMS). MEMS haltere sensors were successfully simulated, designed, and fabricated with a control scheme that enables simple, straightforward decoupling of the signals. Passive mechanical logic was designed to facilitate the decoupling of the forces acting on the sensor. The control scheme was developed that efficiently and accurately decouples the three component parts from the haltere sensors. Individual, coupled, and arrayed halteres were fabricated. A series of static electrical tests and dynamic device tests were conducted, in addition to in-situ bend tests, to validate the simulation results, and these, taken as a whole, indicate that the MEMS haltere sensors will be inherently sensitive to the Coriolis forces caused by changes in angular rate. The successful fabrication of a micro-angular rate sensor represents a substantial breakthrough and is an enabling technology for a number of Army applications, including micro air vehicles (MAVs).
关键词:传感器;自主导航;仿生学;科里奥利效应;本体感受传感器