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Full-Text Articles in Engineering
Electronic Image Stabilization For Mobile Robotic Vision Systems, Michael John Smith
Electronic Image Stabilization For Mobile Robotic Vision Systems, Michael John Smith
Theses and Dissertations
When a camera is affixed on a dynamic mobile robot, image stabilization is the first step towards more complex analysis on the video feed. This thesis presents a novel electronic image stabilization (EIS) algorithm for small inexpensive highly dynamic mobile robotic platforms with onboard camera systems. The algorithm combines optical flow motion parameter estimation with angular rate data provided by a strapdown inertial measurement unit (IMU). A discrete Kalman filter in feedforward configuration is used for optimal fusion of the two data sources. Performance evaluations are conducted by a simulated video truth model (capturing the effects of image translation, rotation, …
System Identification Of An On Orbit Spacecraft's Antenna Dynamics, Christopher M. Sylvester
System Identification Of An On Orbit Spacecraft's Antenna Dynamics, Christopher M. Sylvester
Theses and Dissertations
As a result of previous efforts [Pachter, Barba, 2007] a tight control loop was designed to meet performance specifications while minimizing the feedback control system’s gains of a spacecraft mounted flexible antenna. Emphasis is now shifted to on orbit system identification of the antenna dynamics in order to increase nominal plant knowledge, estimate plant uncertainty bounds, as well as determine the disturbance band. Non-parametric system identification is undertaken. Knowledge of the plant dynamics along with the corresponding uncertainty bounds will provide for the design of a control system which meets the specifications (tracking and disturbance rejection) while at the same …
Implementation Of Collaborative Rf Localization Using A Software-Defined Radio Network, Augustine A. Honore
Implementation Of Collaborative Rf Localization Using A Software-Defined Radio Network, Augustine A. Honore
Theses and Dissertations
This thesis investigates the use of collaboration between sensor nodes that were tasked with localizing a radio frequency emitter. Localization is a necessary component for dynamic spectrum access. Using a set of software-defined radios as our sensors and a received signal strength-based maximum likelihood localization algorithm, we successfully localized transmitting nodes based on their received signal strength. Our experiment was conducted outdoors using a flexible topology that could be shaped into 21 sub-topologies that varied in size, and orientation with respect to the transmitters. This was made possible through application of a time shift concept and a post-processing technique. We …
Using Shadows To Detect Targets In Synthetic Aperture Radar Imagery, Brian P. Donnell
Using Shadows To Detect Targets In Synthetic Aperture Radar Imagery, Brian P. Donnell
Theses and Dissertations
Synthetic Aperture Radar (SAR) can generate high resolution imagery of re- mote scenes by combining the phase information of multiple radar pulses along a given path. SAR based Intelligence, Surveillance, and Reconnaissance (ISR) has the advantage over optical ISR that it can provide usable imagery in adverse weather or nighttime conditions. Certain radar frequencies can even result in foliage or limited soil penetration, enabling imagery to be created of objects of interest that would otherwise be hidden from optical surveillance systems. This thesis demonstrates the capability of locating stationary targets of interest based on the locations of their shadows and …