Publication Date
2008
Document Type
Thesis
Committee Members
Thomas N. Hangartner (Advisor), David F. Short (Committee Member), Julie A. Skipper (Committee Member)
Degree Name
Master of Science in Engineering (MSEgr)
Abstract
Computed Tomography (CT) imaging has found applications in many areas such as diagnostic visualization, quantitative estimation, and therapeutic verification. In this wide range of applications, a CT scanner that can provide the data collection schemes of both second- and third-generation data-collection geometries will be an asset for laboratory research. In this thesis project, we developed a mechanical design and constructed a dual-generation CT scanner that provides flexibility in accommodating a wide range of object sizes with minimum scan time. Using 3-D graphical design software, models of the current second-generation CT scanner and possible solutions for modification were simulated. Based on material availability, cost, and benefits of each design, an appropriate modification scheme was selected to upgrade the current second-generation CT scanner to a third-generation CT scanner.
The modified CT scanner requires integration of both hardware and software components for its motion-control system. An open-loop motion-control system, which incorporates stepper motors, drivers, and a motion controller, is used to provide both the translate-rotate and rotate-only data collection movements. The software was developed in National Instrument's LabVIEW graphical language and is designed to control the movements of both motors and to generate the necessary timing pulses for the detectors. The LabVIEW program provides a flexible, user-friendly interface to the motion-control system and synchronizes all motor movements with the timing pulses to ensure data collection at the desired scanner positions. For both scanner movements, a set of mechanical limit switches monitors the mechanical end positions, and all movements are suspended upon activation of any limit switch. Metal proximity sensors are used for each movement to establish a home position.
The modified CT scanner, with the new hardware and software integrated, provides a full rotation in 3.6 seconds. It retains the flexibility to be operated as a second-generation translate-rotate or a third-generation rotate-only CT scanner.
Page Count
96
Department or Program
Department of Biomedical, Industrial & Human Factors Engineering
Year Degree Awarded
2008
Copyright
Copyright 2008, all rights reserved. This open access ETD is published by Wright State University and OhioLINK.
