Browsing AE Research Publications by Title
Now showing items 154-173 of 182
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Selecting planning horizon length for sequential low-thrust orbit-raising optimization problem
(Univelt Inc., 2019-09)In this paper, we revisit the low-thrust multi-revolution orbit-raising problem formulated as a sequence of optimal control sub-problems, each of which computes the trajectory over a planning horizon. Each sub-problem ... -
Sensor fusion of structural finite element model with inertial sensor data to measure wing deflection of a fixed wing aircraft
(American Institute of Aeronautics and Astronautics Inc, 2020-01-05)This research is a continuation of prior experimental work describing the application of sensor fusion to obtain structural wing deflection data with acceptable accuracy. A Kalman filter design is described introducing a ... -
Sequential low-thrust orbit-raising of all-electric satellites
(MDPI Multidisciplinary Digital Publishing Institute, 2020-06-04)In this paper, we consider a recently developed formulation of the electric orbit-raising problem that utilizes a novel dynamic model and a sequence of optimal control sub-problems to yield fast and robust computations of ... -
Simulated flight testing of an adaptive loss-of-control avoidance pilot advisory display
(American Institute of Aeronautics and Astronautics Inc., 2019-01-06)Loss-of-Control has been consistently deemed the primary contributor to air accidents globally. Systems capable of alerting pilots when impending control loss is predicted to occur have the potential to promote safer flight. ... -
Simulation of a laminar flow model to enable design for manufacturing of laminar flow aerostructures
(CAMX - The Composites and Advanced Materials Exp, 2019-09)Advances in manufacturing technology can produce smooth aircraft surfaces to achieve laminar flow at high Reynolds numbers which can reduce drag significantly. Potential benefits include increased range, improved fuel ... -
Single network adaptive critic aided dynamic inversion for optimal regulation and command tracking with online adaptation for enhanced robustness
(John Wiley & Sons, Inc., 2014-07)To combine the advantages of both stability and optimality-based designs, a single network adaptive critic (SNAC) aided nonlinear dynamic inversion approach is presented in this paper. Here, the gains of a dynamic inversion ... -
Single Network Adaptive Critic aided nonlinear dynamic inversion for suboptimal command tracking
(IEEE, 2011-09-28)Using the Approximate Dynamic Programming (ADP) approach, nonlinear optimal control problems can be solved by using a dual neural network architecture called the Adaptive Critic (AC). A Single Network Adaptive Critic (SNAC) ... -
Solution of Maxwell’s equations for nonrectangular electromagnetic applications
(American Institute of Aeronautics and Astronautics, 2021-01)The use of a fourth-order modified Runge–Kutta (MRK) scheme on a transformed coordinate system with Maxwell’s equations for nonrectangular domains and applications is presented. Maxwell’s equations are the governing equations ... -
Solution of Maxwell’s equations using fourth-order modified Runge-Kutta scheme on transformed coordinates
(American Institute of Aeronautics and Astronautics Inc, 2020-01-05)The development and application of a fourth-order Modified Runge-Kutta (MRK) scheme on a transformed coordinate system with Maxwell’s equations are presented here. Maxwell’s equations are the governing equations for modeling ... -
Sound absorption and transmission loss properties of open-celled aluminum foams with stepwise relative density gradients
(Elsevier Ltd, 2022-05-01)We investigate the acoustical properties of uncompressed and compressed open-celled aluminum metal foams fabricated using a directional solidification foaming process. We compressed the fabricated foams using a hydraulic ... -
Spacecraft maneuver detection using optimal control theory and equations of relative motion
(Univelt Inc., 2018)In this paper, we investigate the spacecraft maneuver detection problem by considering an optimal control formulation, in which we minimize the control effort subject to the Hill-Clohessy-Wiltshire equations of relative ... -
Stochastic optimization framework for spacecraft maneuver detection
(American Institute of Aeronautics and Astronautics Inc, 2020-01-05)The main focus of the paper is the detection and characterization of unobserved spacecraft maneuvers, by considering a stochastic optimal control approach. Specifically, the propagation of uncertainty associated with state ... -
Strain energy release rate analysis of adhesive-bonded composite joints with a prescribed interlaminar crack
(American Institute of Aeronautics and Astronautics, 2009-01)Delamination is among the critical failure modes in fiber-reinforced laminated composite structures. This paper presents an analytical approach by taking into account the first-ply failure in adhesive-bonded composite ... -
Strain energy release rate determination of prescribed cracks in adhesively-bonded single-lap composite joints with thick bondlines
(Elsevier, 2008-07)An analytical model for determining the strain energy release rate due to a prescribed crack in an adhesively-bonded, single-lap composite joint with thick bondlines and subjected to axial tension is presented. An existing ... -
Stress analysis of composite pipe joints under combined torsional and tensile loading
(American Society of Mechanical Engineers (ASME), 2009-09)An analytical model was developed using the first-order laminated shell theory to determine stress and strain distributions within a composite pipe joint under combined torsional and tensile loading. Due to the axisymmetric ... -
Stress and failure analyses of adhesive-bonded composite joints using ASTM D3165 specimens
(American Society for Testing and Materials, 2002-04)An analytical model was developed to determine the stress and strain distributions of single-lap adhesive-bonded composite joints under tension. Both the adherend and the adhesive were assumed linear elastic in the ... -
Stress model and strain energy release rate of a prescribed crack in scarf joint/repair of composite panels
(SAGE Publications, 2015-12)An analytical model for stress distribution was derived and an analytical model for determining the strain energy release rate of a prescribed crack in a scarf joint or a bonded scarf repair of a composite panel was ... -
Stress model of composite pipe joints under bending
(SAGE Publications, 2002-06)Recently, composite pipe is becoming popular in the offshore oil and gas industry due to the new floating designs of various platforms which have made deepwater oil and gas exploration and production more economical and ... -
Stress-strain analysis of a taper-taper adhesive-bonded joint under cylindrical bending
(American Society of Mechanical Engineers (ASME), 1999-07)A model of a taper-taper adhesive-bonded joint under cylindrical bending has been derived using first-order laminated plate theory. Shear correction factors were used to account for transverse shear deformation. A FORTRAN ... -
Study of CL-415 usage in forest service operation
(American Institute of Aeronautics and Astronautics, Inc., 2022-06-20)Results of analyzing airframe usage from a fleet of four CL-415 Super Scooper aircraft flown in support of the United States Forest Service aerial firefighting operations are reported. Data used for this report was collected ...