Pedemis (PortablE Decoupled Electromagnetic Induction Sensor) is a time-domain handheld electromagnetic induction (EMI) instrument with the intended purpose of improving the detection and classification of UneXploded Ordnance (UXO). Pedemis sports nine coplanar transmitters (the Tx assembly) and nine triaxial receivers held in a fixed geometry with respect to each other (the Rx assembly) but with that Rx assembly physically decoupled from the Tx assembly allowing flexible data acquisition modes and deployment options. The data acquisition (DAQ) electronics consists of the National Instruments (NI) cRIO platform which is much lighter and more energy efficient that prior DAQ platforms. Pedemis has successfully acquired initial data, and inversion of the data acquired during these initial tests has yielded satisfactory polarizabilities of a spherical target. In addition, precise positioning of the Rx assembly has been achieved via position inversion algorithms based solely on the data acquired from the receivers during the on-time of the primary field. Pedemis has been designed to be a flexible yet user friendly EMI instrument that can survey, detect and classify targets in a one pass solution. In this paper, the Pedemis instrument is introduced along with its operation protocols, initial data results, and current status.

关键词：光机电；传感器；电磁感应；集成定位

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The objective of the project is to undertake research and development in the area of wireless sensor networks to provide an effective and affordable solution in support increasing requirements for reconnaissance and surveillance. A wireless sensor network, such as unattended ground sensors (UGS) network represents a set of inexpensive sensors of various types (modes) that provide an effective and affordable solution for battlefield surveillance. For example, acoustic sensors could obtain bearing angles of targets, and proximity sensors report the presence or absence of targets within their sensing ranges. The ultimate goal of this research is to explore fundamental performance bounds that determine how well a sensor network can resolve and localize multiple targets as a function of the operating parameters such as sensor density, the threshold settings, and the spacing between the targets. The major contribution of this project is the development of the particle-based probability density (PHD) filter for binary measurements using proximity sensors.

关键词：光机电；传感器；融合；追踪

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The objective of the work reported herein was to use a systems engineering approach to guide development of integrated instrumentation/sensor systems (IISS) incorporating communications, interconnections, and signal acquisition. These require enhanced suitability and effectiveness for diagnostics and health management of aerospace equipment governed by the principles of Condition-based maintenance (CBM). It is concluded that the systems engineering approach to IISS definition provided clear benefits in identifying overall system requirements and an architectural framework for categorizing and evaluating alternative architectures, relative to a bottom up focus on sensor technology blind to system level user needs. CBM IISS imperatives identified include factors such as tolerance of the bulk of aerospace equipment operational environments, low intrusiveness, rapid reconfiguration, and affordable life cycle costs. The functional features identified include interrogation of the variety of sensor types and interfaces common in aerospace equipment applications overmultiplexed communication media with flexibility to allow rapid system reconfiguration to adapt to evolving sensor needs. This implies standardized interfaces at the sensor location (preferably to open standards), reduced wire/connector pin count in harnesses (or their elimination through use of wireless communications).

关键词：光机电；传感器；航空航天设备；仪表维修

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The objective of this project, was therfore, to develop a prototype sensor technology, membrane-extraction(ME)-IMS, that could be used in situ or ex situ, to characterize the extent of groundwater plumes, conduct compliance monitoring around waste facilities or at the leading edge of a plume, and monitor re,merial actions. The IMS instrument could also be used to monitor CHC in the vapor phase.

关键词：光机电；传感器；地下水；原位监测

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The long-term goals of this project are to enable observations of pH in the ocean at depths to 2000 m using sensors deployed on autonomous platforms, particularly profiling floats of the type used in the Argo array. These systems will enable robust, basin-scale observations of changing pH driven by natural and anthropogenic processes. Develop a robust and stable pH sensor for deep-sea applications that is based on the Honeywell Durafet Ion Sensitive Field Effect Transistor (ISFET). The sensor should operate to depths of at least 2000 m. It should have a precision of 0.001 pH and a stability of 0.005 pH over periods up to 5 years throughout the oceanic temperature and salinity range. Capabilities will be demonstrated with deployments on four Webb Research Apex profiling floats.

关键词：光机电；传感器；高压集成；ISFET pH

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The novelly designed optical sensor for autonomous ocean monitoring works on equilibrium principles. When the pH-sensitive reagent solution sitting behind a gas-permeable membrane is exposed to seawater, the CO2 molecules present in the seawater diffuse across the membrane into the reagent and induce a pH change. After equilibrium is reached, the fluorescence is measured and the pCO2 data are recovered from a calibration curve. A specific feature of our measurement technique is the use of excitation ratiometric approach. A violet LED (Light Emitting Diode) and a blue LED are used to excite the sensing reagent through an excitation filter and the pCO2 dependent emission is measured through an emission filter by a photodiode.

关键词：光机电；传感器；光学二氧化碳；海洋监测

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We compared classification capabilities for handheld electromagnetic sensors that were deployed using either a grid-based template for spatial registration or an IMU-based positioning system. Demonstration data were collected at the Aberdeen Proving Ground using both systems. The two data sets were analyzed separately and submitted to the Institute for Defense Analyses for grading. The IMU-based positioning system involved in this demonstration is known as the Small Area Inertial Navigation and Tracking (SAINT) system. It was developed by ENSCO as part of an earlier ESTCP project and enhanced and integrated with the EM61HH sensor in support of this effort. The SAINT system consists of a Honeywell HG1900 IMU and a LEICA DMC. The Honeywell HG1900 IMU consists of orthogonally aligned MEMS accelerometers and gyroscopes that record 3-axis acceleration and rotation rates, respectively enclosed in an 8-cubic inch container. The LEICA DMC is employed to aid the IMU and constrain heading drift. The digital magnetic compass measures the strength and direction of a magnetic field and can be used to determine magnetic north in an environment free of additional magnetic fields. SAINT records all IMU and digital magnetic compass data onto an internal compact flash card.

关键词：光机电；传感器；惯性测量单元；辨识性能

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Results from a field demonstration of autonomous detection, localization, and verification of multiple acoustic events using sparsely deployed unattended ground sensors, unmanned aerial vehicles (UAV) as data mules, and a ground control interface are discussed. A novel algorithm is demonstrated to address the problem of multiple event acoustic source localization in the presence of false and missed detections. We also demonstrate an algorithm to route a UAV equipped with a radio to collect data from sparsely deployed ground sensors that takes advantage of communication range of the aircraft while adhering to kinematic constraints of the UAV. A second UAV was utilized to provide video verification of localized events to a human operator at a ground control station.

关键词：光机电；传感器；定位；无人机

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This research addresses theoretical and computational issues for estimation of gas concentration associated with an emitting stationary or moving source. Estimation of the concentration field provides a superior ability for detection of the gas source location, assessment of possible impacts and eventual containment. The model based concentration estimation is made possible via a sensing aerial vehicle (SAV). The theoretical component considers an abstract and finite-dimensional approximation framework that strongly couples theoretical estimation and control with advanced computational fluid dynamics methods. The gas dispersion model is based on the 2D advection diffusion equation with variable eddy diffusivities and ambient winds. The process state estimator is based on a 2D adaptive, multi grid, multi step finite volume method with upwind and flux limiting. The grid is adapted with local refinement and coarsening during the process state estimation, in order to improve accuracy and efficiency. The SAV motion dynamics is incorporated into the spatial process and its guidance is linked to the performance of the state estimator.

关键词：光机电；传感器；气体源；检测

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In this paper, the output parameters of the planar electromagnetic sensor have observed with different kind of water samples at different concentrations. The output parameters have been derived and tested to be incorporated with independent component analysis (ICA) and as inputs for an analysis model. The analysis model targeted to estimate the amount of nitrate contamination in water samples with the assistance of ICA based on FastICA fixed point algorithm under the contrast functions of pow3 and tanh. Nitrates sample in the form of ammonium nitrates (NH_4NO_3), each of different concentration between 5 mg and 20 mg dissolved in 1 litre of deionized water (mili-q) was used as one of the main references. A model based on independent component analysis was developed to estimate nitrate contamination in natural water source. The model was tested with two sets of mixed NH_4NO_3 and (NH_4)_2HPO_4 water samples based on Manawatu river water. From the results, the model can acceptably detect the presence of nitrate in Manawatu River and capable of distinguishing the concentration level in the presence of other type of contamination. Furthermore, the effect of temperature change was also observed in this study. The system and approach presented in this paper has the potential to be used as a useful tool for water sources monitoring.

关键词：光机电；传感器；硝酸；温度检测

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