28,311 research outputs found
The 3D laser radar vision processor system
Loral Defense Systems (LDS) developed a 3D Laser Radar Vision Processor system capable of detecting, classifying, and identifying small mobile targets as well as larger fixed targets using three dimensional laser radar imagery for use with a robotic type system. This processor system is designed to interface with the NASA Johnson Space Center in-house Extra Vehicular Activity (EVA) Retriever robot program and provide to it needed information so it can fetch and grasp targets in a space-type scenario
The MEV project: design and testing of a new high-resolution telescope for Muography of Etna Volcano
The MEV project aims at developing a muon telescope expressly designed for
the muography of Etna Volcano. In particular, one of the active craters in the
summit area of the volcano would be a suitable target for this experiment. A
muon tracking telescope with high imaging resolution was built and tested
during 2017. The telescope is a tracker based on extruded scintillating bars
with WLS fibres and featuring an innovative read-out architecture. It is
composed of three XY planes with a sensitive area of \SI{1}{m^2}; the angular
resolution does not exceeds \SI{0.4}{\milli\steradian} and the total angular
aperture is about \SI{45}{\degree}. A special effort concerned the design
of mechanics and electronics in order to meet the requirements of a detector
capable to work in a hostile environment such as the top of a tall volcano, at
a far distance from any facility. The test phase started in January 2017 and
ended successfully at the end of July 2017. An extinct volcanic crater (the
Monti Rossi, in the village of Nicolosi, about 15km from Catania) is the target
of the measurement. The detector acquired data for about 120 days and the
preliminary results are reported in this work
Grid computing for the numerical reconstruction of digital holograms
Digital holography has the potential to greatly extend holography's applications and move it from the lab into the field: a single CCD or other solid-state sensor can capture any number of holograms while numerical reconstruction within a computer eliminates the need for chemical processing and readily allows further processing and visualisation of the holographic image. The steady increase in sensor pixel count and resolution leads to the possibilities of larger sample volumes and of higher spatial resolution sampling, enabling the practical use of digital off-axis holography.
However this increase in pixel count also drives a corresponding expansion of the computational effort needed to numerically reconstruct such holograms to an extent where the reconstruction process for a single depth slice takes significantly longer than the capture process for each single hologram. Grid computing - a recent innovation in largescale distributed processing -provides a convenient means of harnessing significant computing resources in an ad-hoc fashion that might match the field deployment of a holographic instrument.
In this paper we consider the computational needs of digital holography and discuss the deployment of numericals reconstruction software over an existing Grid testbed. The analysis of marine organisms is used as an exemplar for work flow and job execution of in-line digital holography
Proton-counting radiography for proton therapy: a proof of principle using CMOS APS technology
Despite the early recognition of the potential of proton imaging to assist proton therapy (Cormack 1963 J. Appl. Phys. 34 2722), the modality is still removed from clinical practice, with various approaches in development. For proton-counting radiography applications such as computed tomography (CT), the water-equivalent-path-length that each proton has travelled through an imaged object must be inferred. Typically, scintillator-based technology has been used in various energy/range telescope designs. Here we propose a very different alternative of using radiation-hard CMOS active pixel sensor technology. The ability of such a sensor to resolve the passage of individual protons in a therapy beam has not been previously shown. Here, such capability is demonstrated using a 36 MeV cyclotron beam (University of Birmingham Cyclotron, Birmingham, UK) and a 200 MeV clinical radiotherapy beam (iThemba LABS, Cape Town, SA). The feasibility of tracking individual protons through multiple CMOS layers is also demonstrated using a two-layer stack of sensors. The chief advantages of this solution are the spatial discrimination of events intrinsic to pixelated sensors, combined with the potential provision of information on both the range and residual energy of a proton. The challenges in developing a practical system are discussed
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