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1	Vision-based Target Localization from a Small, Fixed-wing Unmanned Air Vehicle Redding, Joshua D. 07 July 2005 (has links) (PDF) Unmanned air vehicles (UAVs) are attracting increased attention as their envelope of suitable tasks expands to include activities such as perimeter tracking, search and rescue assistance, surveillance and reconnaissance. The simplified goal of many of these tasks is to image an object for tracking or information-gathering purposes. The ability to determine the inertial location of a visible, ground-based object without requiring a priori knowledge of its exact location would therefore prove beneficial. This thesis discusses a method of localizing a ground-based object when imaged from a fixed-wing UAV. Using the target's pixel location in an image, with measurements of UAV position, attitude and camera pose angles, the target is localized in world coordinates. This thesis also presents a study of possible error sources and localization sensitivities to each source. From this study, an accuracy within 15.5 m of actual target location is expected. Also, several methods of filtering are presented, which allow for effective noise reduction. Finally, filtered hardware results are presented that verify these expectations by localizing a target from a fixed-wing UAV using on-board vision to within 10.9 meters. localization UAV unmanned UAV vision Mechanical Engineering
2	Feature-based Mini Unmanned Air Vehicle Video Euclidean Stabilization with Local Mosaics Gerhardt, Damon Dyck 01 February 2007 (has links) (PDF) Video acquired using a camera mounted on a mini Unmanned Air Vehicle (mUAV) may be very helpful in Wilderness Search and Rescue and many other applications but is commonly plagued with limited spatial and temporal field of views, distractive jittery motions, disorienting rotations, and noisy and distorted images. These problems collectively make it very difficult for human viewers to identify objects of interest as well as infer correct orientations throughout the video. In order to expand the temporal and spatial field of view, stabilize, and better orient users of noisy and distorted mUAV video, a method is proposed of estimating in software and in real time the relative motions of each frame to the next by tracking a small subset of features within each frame to the next. Using these relative motions, a local Euclidean mosaic of the video can be created and a curve can be fit to the video's accumulative motion path to stabilize the presentations of both the video and the local Euclidean mosaic. The increase in users' abilities to perform common search-and-rescue tasks of identifying objects of interest throughout the stabilized and locally mosaiced mUAV video is then evaluated. Finally, a discussion of remaining limitations is presented along with some possibilities for future work. feature-based mini unmanned air vehicle mUAV UAV mUAV vision UAV vision video stabilization video mosaic Euclidean mosaic Euclidean stabilization local mosaic aerial video E-mosaic stable-E stable-E-mosaic homography RANSAC filter short circuit jitter Computer Sciences

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Vision-based Target Localization from a Small, Fixed-wing Unmanned Air Vehicle

Feature-based Mini Unmanned Air Vehicle Video Euclidean Stabilization with Local Mosaics