Search results for "Nonlinear oscillations"

showing 5 items of 5 documents

Hidden oscillations in aircraft flight control system with input saturation

2013

Abstract The presence of actuator saturation can dramatically degrade the system performance. Since the feedback loop is broken when the actuator saturates the unstable modes of the regulator may then drift to undesirable values. The consequences are that undesired nonlinear oscillations appear and that the settling time may unacceptably increase. Rigorous analysis of nonlinear aircraft models is a very difficult task, that is why a numerical simulation is often used as an analysis and design tool. In this paper difficulties of numerical analysis related to the existence of hidden oscillations in the aircraft control system are demonstrated.

EngineeringSettling timebusiness.industryDescribing functionControl engineeringGeneral MedicineFeedback loopAircraft flight control systemNonlinear systemControl theoryControl systemNonlinear OscillationsbusinessActuatorIFAC Proceedings Volumes
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Steady states and nonlinear buckling of cable-suspended beam systems

2018

This paper deals with the equilibria of an elastically-coupled cable-suspended beam system, where the beam is assumed to be extensible and subject to a compressive axial load. When no vertical load is applied, necessary and sufficient conditions in order to have nontrivial solutions are established, and their explicit closed-form expressions are found. In particular, the stationary solutions are shown to exhibit at most two non-vanishing Fourier modes and the critical values of the axial-load parameter which produce their pitchfork bifurcation (buckling) are established. Depending on two dimensionless parameters, the complete set of resonant modes is devised. As expected, breakdown of the p…

Perturbation (astronomy)010103 numerical & computational mathematicsBiparametric resonance; Cable-suspended beam; Nonlinear oscillations; Pitchfork bifurcation; Stationary solutions; Suspension bridgeCable-suspended beam01 natural sciencesBiparametric resonanceNonlinear oscillationssymbols.namesakeStationary solutions0101 mathematicsNonlinear bucklingNonlinear OscillationsPhysicsMechanical EngineeringPitchfork bifurcationMechanicsCondensed Matter PhysicsSuspension bridge010101 applied mathematicsPitchfork bifurcationFourier transformBucklingMechanics of MaterialssymbolsAxial loadDimensionless quantity
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Sharp conditions for rapid nonlinear oscillations

2000

Nonlinear systemApplied MathematicsNonlinear resonanceMathematical analysisNonlinear OscillationsAnalysisMathematicsNonlinear Analysis: Theory, Methods & Applications
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Buckling and nonlinear dynamics of elastically coupled double-beam systems

2016

Abstract This paper deals with damped transverse vibrations of elastically coupled double-beam system under even compressive axial loading. Each beam is assumed to be elastic, extensible and supported at the ends. The related stationary problem is proved to admit both unimodal (only one eigenfunction is involved) and bimodal (two eigenfunctions are involved) buckled solutions, and their number depends on structural parameters and applied axial loads. The occurrence of a so complex structure of the steady states motivates a global analysis of the longtime dynamics. In this regard, we are able to prove the existence of a global regular attractor of solutions. When a finite set of stationary s…

Buckling; Double-beam system; Global attractor; Nonlinear oscillations; Steady states; Mechanics of Materials; Mechanical Engineering; Applied MathematicsSteady statesBucklingApplied MathematicsMechanical Engineering010102 general mathematicsEigenfunctionDouble-beam system01 natural sciencesGlobal attractorNonlinear oscillations010101 applied mathematicsVibrationNonlinear systemClassical mechanicsBucklingMechanics of MaterialsAttractor0101 mathematicsNonlinear OscillationsFinite setBeam (structure)MathematicsInternational Journal of Non-Linear Mechanics
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Advances in Design, Simulation and Manufacturing IV

2021

This book reports on topics at the interface between mechanical and chemical engineering, emphasizing design, simulation, and manufacturing. Specifically, it covers recent developments in the mechanics of solids and structures, numerical simulation of coupled problems, including fatigue, fluid behavior, particle movement, pressure distribution. Further, it reports on developments in chemical process technology, heat and mass transfer, energy-efficient technologies, and industrial ecology. Based on the 4th International Conference on Design, Simulation, Manufacturing: The Innovation Exchange (DSMIE-2021), held on June 8-11, 2021, in Lviv, Ukraine, this second volume of a 2-volume set provide…

Granular Materials SeparationNonlinear OscillationsHydraulic motorsRotor SystemsDSMIE 2021Frictional ContactManufacturing engineeringActive Hydrodynamic RegimesNanocrystalline Hardened LayerOrgano-mineral FertilizerHydrodynamic characteristicsOilfield Wastewater TreatmentSlider-crank mechanismsVibratory EquipmentHydraulic Mechatronic SystemsFriction treatmentModels of Hydraulic DrivesHydrovolumetric transmissionSwirling FlowMechanical Control SystemsVolume (compression)
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