Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 84 for “"control surface"”.
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Aircraft System Identification Approach for Control Surface Fault Diagnosis
… a model-based FDD approach for identifying control-surface loss of effectiveness on a small, fixed-wing research aircraft. The work considers several real-time system identification methods to estimate changes in control effectiveness and provide fault information to a fault-tolerant control …
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Design Demonstration and Optimization of a Morphing Aircraft Control Surface Using Flexible Matrix Composite Actuators
The morphing of aircraft wings for flight control started as a necessity for the Wright Brothers but quickly fell out of favor as aircraft increased speed. Currently morphing aircraft control is one of many ideas being explored as we seek to improve aircraft efficiency, reduce noise, and other …
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An investigation of the heat transfer and transport mechanisms which control surface water during glaze ice accretion
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1988.
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The effect of free stream disturbances and control surface deflections on the performance of the Wortmann airfoil at low Reynolds numbers
… bubble which frequently occurs on the upper surface of the wing is found to dominate its performance and gives rise to a hysteresis loop for lift and drag. Changes in airfoil performance due to positive flap or control surface deflections resemble changes witnessed at higher Reynolds numbers. …
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Actuator-Work Concepts Applied to Morphing and Conventional Aerodynamic Control Devices
… for the comparison of various aerodynamic control device configurations. This estimated "actuator work," or practical work as it will be referred to as in this thesis, is based on the aerodynamic and structural resistance to a control surface deflection. It is meant to represent the …
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Retrofit systems for reconfiguration in civil aviation
… a reconfiguration module to an existing control law is reported in this thesis. The concept is motivated by the need for low cost, add-on modules that improve air safety in the existing fleet of civil air transport vehicles. A direct adaptive approach that accommodates control surface …
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Macro Fiber Composite Actuated Control Surfaces with Applications Toward Ducted Fan Vehicles
In most man-made flight, vehicle control is achieved by deflecting flaps. However, in nature, morphing surfaces are found on both flying and swimming creatures. Morphing is used in nature because it is a more efficient form of control. This thesis investigates using morphing flaps to control a …
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The effect of a knurled heat transfer surface upon pool nucleate boiling of normal pentane
… of knurling a nucleate boiling heat transfer surface was studied. The knurling utilized produced regular, four-sided, adjacent pyramids with an apex angle of 90 degrees. Four knurling densities were used ranging from 416 to 2591 pyramids per square inch. The transfer surface was gold-plated …
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The contribution of the pectoral fins, body, and the ribbon fin to turning maneuvers of a gymnotiform swimmer
… complex environments. Fishes with traditional control surfaces primarily use body bending and pectoral fins to turn. However, little is known about how fishes with atypical control surfaces facilitate turning. This study investigated the weakly electric Black ghost knifefish (<em>Apteronotus …
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Effect of Centrifugal Stiffening on the Natural Frequencies of Aircraft Wings During Rapid Roll Maneuvers
… for the mAEWing2 aircraft and the roll rate, control surface deflection and angle of attack are identified as the parameters to be studied. For a given angle of attack and control surface deflection, the centrifugal forces in the aircraft in steady roll are determined using trim analysis. …
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L1 adaptive control augmentation system for the X-48B Aircraft
… thesis considers the application of L1 adaptive control methodology to a model of the X-48B Blended Wing Body aircraft. We explicitly verify the performance bounds of the adaptive flight control system at various flight conditions. We demonstrate that the resulting L1 adaptive controller does not …
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Dynamic Inversion and Backstepping Controller Robustness Analysis for a Reusable Launch Vehicle
… gain tuning techniques are used to design a controller for a specific mission, which may hinder the vehicle’s ability to perform multiple missions if gains have to be re-tuned. Advanced nonlinear control methods like dynamic inversion and backstepping may eliminate the need to use classical …
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Approximations for Singular Integral Equations
… flow. The flap can be viewed as an active control surface to dampen vibrations that contribute to flutter. The goal of this work is to provide accurate approximations for weakly singular neutral equations using finite elements as basis functions for the initial function space. Several …
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The development of a fixed wing aircraft analysis and design flight dynamic software
… software for flight dynamic analysis and controlling the behavior of a fixed-wing aircraft. For a given aircraft geometry, mass and inertia properties, and flight conditions, the software was designed in such a way to start the estimation of aerodynamic characteristics, trimmed flight, …
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Performance of an airfoil with a power-saving, tab-assisted flap system
… study investigated the feasibility of reducing control surface input power with the use of a tab-assisted flap. Wind tunnel tests were conducted at the University of Illinois at Urbana-Champaign (UIUC) on a NACA 3415 airfoil model with a flap including a trim tab. Measurements were taken for two …
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A thesis on the application of neural network computing to the constrained flight control allocation problem
… a neural network to solve the constrained flight control allocation problem is investigated for the purposes of developing guidelines for the selection of a neural network structure as a function of the control allocation problem parameters. The control allocation problem of finding the …
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Numerical simulations of subsonic aeroelastic behavior and flutter suppression by active control
… of a wing has been developed. The air, wing, and control surface are considered to be a single dynamical system. All equations are solved simultaneously in the time domain by a predictor-corrector method. The scheme allows nonlinear aerodynamic and structural models to be used and subcritical, …
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Robust nonlinear controller based on set propagation
A novel control method, based on interval analysis, that optimises the control surface (or u-surface) for sampled systems with output disturbances is demonstrated on a driven pendulum with actuator constraints. The fitness function to be maximized is the probability of each state of the system …
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Harmonic Acoustics for Single Cell Manipulation
… and temporal modulation methods to generate and control surface acoustic waves to dynamically manipulate single cells. And further biophysical analysis studies, such as the assay of differences in intercellular adhesion among cancer cell lines with different malignancies and metastatic potentials …
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Design and Development of Stability and Control Systems for Small, Deployable Aircraft
… requirements present challenges in designing control surfaces with adequate stability and control performance. To satisfy the stowability requirements, the tail was designed with an oblique hinge in which the deployment axis doubles as the control-surface actuation axis. Actuation mechanics, …
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