University of Michigan

Kimberlee Jane Kearfott

Douglas Scott McGregor

Roland R Benke

Bozidar Stojadinovic

Clair J Branch-Sullivan

An image reconstruction algorithm system for hazardous source mapping. The algorithm system can be used to automate and optimize the search path of a movable vehicle (such as a UAV), equipped with detection capability. The algorithm allows the vehicle to localize hazardous sources in multiple scenarios effectively. Hazard mapping is formulated as an inverse problem and solved either with a deconvolution or a reconstruction algorithm, according to the problem complexity. The algorithms can use the Maximum a Posteriori (MAP) and the least square regression algorithm, respectively. However, alternative algorithms can be used as set forth herein. The source mapping algorithms are able to provide a quantitative estimation of the hazard source magnitude. A non-negative version of the least square algorithm is used to reconstruct the map at each step of the navigation algorithm of the vehicle. The navigation algorithm correctly located single and multiples simulated hazardous sources.

Rapid characterization of the sources of electromagnetic signals and environmental substances

A method of determining the radiation type and energy distribution of a radiation source that outputs radiation. The method including providing a plurality of detector materials and exposing the plurality of detector materials to the radiation. Each of the plurality of detector materials stores a signal in response to being exposed to the radiation. The signals are representative of the radiation. The plurality of detector materials is stimulated to output the signals as measured signals. These measured signals are used to determine the radiation type and energy distribution of the radiation.

Integrative and real-time radiation measurement methods and systems

A neutron elastic scattering detector device for non-invasively detecting the presence of at least one predetermined element of an object of interest. The detector device comprises a neutron source that simultaneously outputs, at a creation time, a neutron in a first direction and an associated baseline particle in a second direction. The first direction is opposite of the second direction. The neutron can impinge upon the predetermined element of the object of interest and scatter therefrom in a third direction. A baseline particle detector system detects the baseline particle and outputs a baseline signal characteristic thereof. A neutron detector system detects the neutron and outputs a scattering signal in characteristic thereof. The processing unit analyzes the baseline signal and the scattering signal to determine the presence of the predetermined element.

Neutron irradiative methods and systems

A high-speed, three-dimensional, gamma-ray imaging method and system as well as a detector and array of such detectors for use therein are provided which characterize radioactivity distributions in nuclear and radioactive waste and materials facilities by superimposing radiation images on a view of the environment using see-through display screens or shields to provide a stereoscopic view of the radiation. The method and system provide real-time visual feedback about the locations and relative strengths of radioactive sources. The method and system dynamically provide continuous updates to the displayed image illustrating changes, such as source movement. A pair of spaced gamma-ray cameras of a detector subsystem function like &ldquo;gamma eyes&rdquo;. A pair of CCD cameras may be coupled to the detector subsystem to obtain information about the physical architecture of the environment. A motion tracking subsystem is used to generate information on the user's position and head orientation to determine what a user &ldquo;sees&rdquo;. The invention exploits the human brain's ability to naturally reconstruct a 3D, stereoscopic image from 2D images generated by two &ldquo;imagers&rdquo; separated by a known angle(s) without the need for 3D mathematical image reconstruction. The method and system are not only tools for minimizing human exposure to radiation thus assisting in ALARA (As Low As Reasonably Achievable) planning, but also are helpful for identifying contamination in, for example, laboratory or industrial settings. Other optically-invisible radiation such as infrared radiation caused by smoldering fires may also be imaged. Detectors are manufactured or configured in curvilinear geometries (such as hemispheres, spheres, circles, arcs, or other arrangements) to enable sampling of the ionizing radiation field for determination of positional activity (absolute or relative amounts of ionizing radiation) or spectroscopy (energy distributions of photons). More than one detector system may be used to obtain three-dimensional information. The detector systems are specifically suitable for direct visualization of radiation fields.

Method and system for high-speed, 3D imaging of optically-invisible radiation

A method and system for detecting ionizing radiation emitted by material located over an extended area are provided. The method and system include a radiation detector disposed within a detector space on a detection axis. An array of collimating louvers is positioned about the radiation detector and is movable between different polar positions or angles relative to the detection axis. A mechanism is provided for moving the array of collimating louvers between the different polar angles to collimate the ionizing radiation from different locations over the area. The detector produces electrical signals as a function of the polar positions of the array of collimating louvers.

Method and system for detecting ionizing radiation

A radiation detector system includes detectors having different properties (sensitivity, energy resolution) which are combined so that excellent spectral information may be obtained along with good determinations of the radiation field as a function of position.

Method and system for determining depth distribution of radiation-emitting material located in a source medium and radiation detector system for use therein

A method, system and a radiation detector system for use therein are provided for determining the depth distribution of radiation-emitting material distributed in a source medium, such as a contaminated field, without the need to take samples, such as extensive soil samples, to determine the depth distribution. The system includes a portable detector assembly with an x-ray or gamma-ray detector having a detector axis for detecting the emitted radiation. The radiation may be naturally-emitted by the material, such as gamma-ray-emitting radionuclides, or emitted when the material is struck by other radiation. The assembly also includes a hollow collimator in which the detector is positioned. The collimator causes the emitted radiation to bend toward the detector as rays parallel to the detector axis of the detector. The collimator may be a hollow cylinder positioned so that its central axis is perpendicular to the upper surface of the large area source when positioned thereon. The collimator allows the detector to angularly sample the emitted radiation over many ranges of polar angles. This is done by forming the collimator as a single adjustable collimator or a set of collimator pieces having various possible configurations when connected together. In any one configuration, the collimator allows the detector to detect only the radiation emitted from a selected range of polar angles measured from the detector axis. Adjustment of the collimator or the detector therein enables the detector to detect radiation emitted from a different range of polar angles. The system further includes a signal processor for processing the signals from the detector wherein signals obtained from different ranges of polar angles are processed together to obtain a reconstruction of the radiation-emitting material as a function of depth, assuming, but not limited to, a spatially-uniform depth distribution of the material within each layer. The detector system includes detectors having different properties (sensitivity, energy resolution) which are combined so that excellent spectral information may be obtained along with good determinations of the radiation field as a function of position.

Growing community of inventors

Ann Arbor, MI, United States of America

Kimberlee Jane Kearfott