Global ETD Search
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Showing 1 to 15 of 15 for “"Wind estimation"”.
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Mesospheric wind estimation with the Jicamarca MST radar
… con figuration used for mesospheric Doppler wind measurements as well as the data processing procedure used to obtain wind estimates from spectral data. The procedure was initially developed by Sheth et al. [2006] and improved by Smith [2014], but it still gave biased wind estimates when the …
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Spectral processing and wind estimation with Jicamarca mesospheric radar data
… to estimate the zonal, meridional, and vertical wind velocities. The winds and spectral parameters will be uploaded to the CEDAR Archival Madrigal Database. Winds and spectral data are also displayed at http://remote2.csl.illinois.edu/MSTISR/showmaps_2 utilizing dynamic javascript tools. Abstract …
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Robust State Estimation, Uncertainty Quantification, and Uncertainty Reduction with Applications to Wind Estimation
Indirect wind estimation onboard unmanned aerial systems (UASs) can be accomplished using existing air vehicle sensors along with a dynamic model of the UAS augmented with additional wind-related states. It is often desired to extract a mean component of the wind the from frequency fluctuations …
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A machine learning approach to wind estimation and uncertainty using remote dropsondes and deterministic forecasts
… and a dropsonde measurement to predict the winds over a DZ. The uncertainty in the DZ wind prediction is inferred using quantile regression. The uncertainty estimate is nonstatic meaning it is unique for each airdrop mission, and the uncertainty estimate is derived from data that is already …
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Identification of Unsteady Flight Dynamic Models and Model-based Wind Estimation with Flight Test Validation
… weather modeling can benefit from improved wind sensing in the Earth's atmospheric boundary layer (ABL). Small, low-cost, uncrewed aircraft (drones) can be used to measure wind and a distribution of these vehicles could potentially provide measurements with much greater density and …
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An Invariant Extended Kalman Filter for Indirect Wind Estimation Using a Small, Fixed-Wing Uncrewed Aerial Vehicle
… temperature, and humidity) and kinematic state (wind velocity) of the atmospheric boundary layer (ABL) can aid in numerical weather prediction, help scientists assess climatological and topological features over a region, and can be incorporated into flight path planning and control of small …
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Towards Detecting Atmospheric Coherent Structures using Small Fixed-Wing Unmanned Aircraft
… prediction of material transport by turbulent winds, such as those observed in the Earth's Atmospheric Boundary Layer. In this dissertation, both theory and experimental methods are developed for utilizing small fixed-wing unmanned aircraft systems (UAS) in detecting these atmospheric coherent …
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An Implementation of Field-Wise Wind Retrieval for Seawinds on QuikSCAT
<p>Field-wise wind estimation (also known as model-based wind estimation) is a sophisticated technique to derive wind estimates from radar backscatter measurements. In contrast to the more traditional method known as point-wise wind retrieval, field-wise techniques estimate wind field model …
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An application of a proposed airdrop planning system
… research converges on tools to assist in the estimation and improvement of airdrop landing errors. Wind estimation was studied to better understand the landing errors that stem from different wind prediction methods, as well as from onboard wind measurement systems. Other uncertainties, …
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Improved gust rejection for a micro coaxial helicopter in urban environments
… areas are notoriously complex with the mean winds varying spatially and temporally with sharp changes in wind magnitude and direction over small distances. This results in velocity perturbations which are on the same order of magnitude as the maximum flight speeds of micro rotorcraft leading …
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Nonlinear Observers for Aircraft Maneuvering in Wind
Knowledge of wind velocity is fundamental across fields from atmospheric science to aeronautics, yet direct wind sensing is often constrained by operational limits. This motivates indirect wind estimation methods that infer wind from aircraft motion. However, typical model-based estimators lack …
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Wind and Wake Sensing with UAV Formation Flight: System Development and Flight Testing
Wind turbulence including atmospheric turbulence and wake turbulence have been widely investigated; however, only recently it become possible to use Unmanned Aerial Vehicles (UAVs) as a validation tool for research in this area. Wind can be a major contributing factor of adverse weather for …
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Design of Flight Control Laws for a Novel Stratospheric Dual-Aircraft Platform
… without propulsion, using vertical wind shear. DAP offers the potential of a low-cost atmospheric satellite. This thesis presents the results of an initiative to demonstrate this novel flight concept through modeling, simulation, and flight testing at Embry-Riddle Aeronautical …
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Accurate Target Geolocation and Vision-Based Landing with Application to Search and Engage Missions for Miniature Air Vehicles
… accomplish this, methods are presented for bias estimation, wind estimation, recursive least squares filtering, and optimal flight path generation. Hardware results are presented which demonstrate the ability to consistently localize targets to within 5 m regardless of wind conditions. The second …
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Sensing Atmospheric Winds from Quadrotor Motion
Wind observations that are critical for understanding meteorological processes occurring inside of the Earth's atmospheric boundary layer (ABL) are sparse due to limitations of conventional atmospheric sensors. In this dissertation, dynamic systems and estimation theory are combined with …