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Showing 1 to 14 of 14 for “"assumed modes"”.
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Frequency dependence on the temperature in nuclear quadrupole resonance of sodium bromate
… extended by Kushida. The inequality of the two assumed modes of bromate-group vibration as well as the possibility of temperature dependence associated with these bromate-group vibrations were considered. Results indicate that a temperature dependence of the bromate-group vibrations must be …
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An Analytical Investigation of Flapping Wing Structures for Micro Air Vehicles
… model addresses this need. A time-periodic assumed-modes beam analysis of a flapping, flexible wing undergoing linear deformations is developed from a beam analysis of a helicopter blade. The resultant structural model includes bending and torsion degrees of freedom. The model is …
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Optimal joint trajectory planning for a robot with elastic links
… derive the dynamic equations of motion and the Assumed-modes method is used for numerical solution. The proposed optimum joint angle trajectory can be implemented by off-line programming for the minimum vibration of robot arms; One and two flexible links cases are investigated and computer …
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Modeling of the UNLV-Aro light-weight robot using Lagrange's assumed mode method, symbolic manipulation, and numerical simulation
… mechanics were used to model this system. Assumed modes method was used to approximate the vibration mode shape of the links. Using these analytical techniques in conjunction with the inverse dynamics method, a set of equations of motion was formulated to describe the vibrations of the …
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Optimal control of a rotating cylinder partially filled with ideal fluid
… lower suspension mass. For (2) the method of assumed modes is used to discretize the system and obtain a set of n linear algebraic equations. In both cases the treatment is two dimensional and axial motion of the fluid is considered negligible. In both models, the uncontrolled system, shown by …
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Time optimal slewing of flexible spacecraft
… a discrete nonlinear model is obtained by the assumed modes method. The problem is first solved in a discrete linearized space by parameter optimization. Optimality is verified by Pontryagin’s Maximum Principle. The linear solutions are then used to obtain time optimal solutions for the …
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Nonlinear Dynamics Analysis and Control of Space Vehicles with Flexible Structures
… beam. Discretization techniques, such as the assumed modes method and the finite element method, are used to model the coupled dynamics by transforming the partial differential equations of motion into a finite set of differential equations. State feedback control laws are designed to achieve …
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Multifunctional Piezoelectric Energy Harvesting Concepts
… load during operation. An electromechanical assumed modes model used to predict the coupled electrical and mechanical response of a cantilever self-charging structure subjected to harmonic base excitation is described. Experimental evaluation of a prototype self-charging structure is then …
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Dynamics of spinning flexible satellites
… coordinates are discretized by the assumed-modes method based on the Rayleigh-Ritz approach. The matrix form of the linearized equations of motion, which is of gyroscopic type, can be reduced to a general matrix multiplied by the state vector. The constrained system Hamiltonian is …
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Hybrid Active/Passive Models with Frequency Dependent Damping
… equations of motion, which are discretized using assumed modes method. The frequency dependent damping is modeled using the Golla-Hughes-McTavish (GHM) method and the system is analyzed in the time domain. GHM increases the size of the original system by adding fictitious dissipation coordinates …
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Prediction of Limit Cycle Oscillation in an Aeroelastic System using Nonlinear Normal Modes
… recently developed method of nonlinear normal modes (NNM) is investigated for LCO calculation. Nonlinear normal modes were used to analyze a spring-mass-damper system with nonlinear damping and stiffness to demonstrate the ability and limitations of the method to identify limit cycle …
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Electromechanical Modeling of Piezoelectric Energy Harvesters
… approximate electromechanical solution using the assumed-modes method is presented and it can be used for modeling of asymmetric and moderately thick energy harvester configurations. Finally, a piezo-magneto-elastic energy harvester is introduced as a non-conventional broadband energy harvester.
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Linear and non-linear deformations of a wind turbine blade considering warping and all aeroelastic load couplings
… all these factors has not been done before. The "assumed modes method" was used, in which displacements are assumed to be an expansion of products of time-step dependent constants and polynomial functions of x (where x is the coordinate along the length of the blade) that satisfy the boundary …
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Structural health monitoring of inland navigation infrastructure
The inland navigation system in the U.S. is a civil infrastructure network that relies on the performance of a vast array of infrastructure assets scattered across the nation to function successfully. The system is critical to the U.S. economy, allowing the transportation of billions of dollars in …