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Showing 1 to 20 of 41 for “"Snap-Through"”.
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Prediction of snap-through instability under harmonic excitation
A method is developed to predict the critical harmonic excitation of systems undergoing nonlinear oscillations. The method is based on the total energy approach which limits the system responses within a region bounded by a critical total energy in the phase space. Three one-degree-of-freedom …
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Snap-through of a shallow arch subjected to random excitation
… under low intensity loading, but will snap back and forth about its horizontal axis under high intensity loading. The parameter of interest is the time of first snap-through of the shallow arch under random load. This is defined as the time taken for the arch to snap to the other side …
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Large Elastic Deformations and Snap-Through of Shallow Doubly-Curved Shells
Made available in DSpace on 2014-12-08T23:56:45Z (GMT). No. of bitstreams: 1 6706656.pdf: 5239827 bytes, checksum: 6ae9def427101d87e17e1333365f7202 (MD5) Previous issue date: 1966
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Use of Piezoelectric Actuators to Effect Snap-Through Behavior of Unsymmetric Composite Laminates
… the use of piezoelectric actuators to effect snap-through behavior of simple unsymmetric cross-ply composite laminates is examined. Many unsymmetric laminates have more than one stable room-temperature shape and can be snapped through from one stable shape to another. In this new concept for …
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SMA-Induced Deformations In general Unsymmetric Laminates
… stable configuration to the other by a simple snap-through action. This situation offers the opportunity to use shape memory alloys (SMA) attached to the laminate to generate the snap-through forces and change the shape of the laminate on command. Presented is a model which can predict …
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A Variable Stiffness Energy Dissipation Device for Vibration Control of Steel Frames
… imparted to a structure. However, the use of snap-through instability to dissipate energy and control vibration is rather new. The proposed energy dissipation device is a passive device that can exhibit snap-through and snap-back behaviors; and in the process of doing so, is able to dissipate …
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Transient behavior of curved structures
… extreme loadings, the structure might undergo snap-through buckling, i.e., the structure is forced to its inverted configuration, inducing fatigue. The focus of this research is the development of a reliable and accurate model for simulating the nonlinear response of shallow arches under …
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At the Intersection of Bistability and Elastic Instability: Switching and Locking Structures using Asymmetric Carbon Fiber Composites
… from one state to the other is termed as a snap-through process. This study for the first time investigates the bistable laminates from a holistic perspective by understanding their quasi-static behaviors in mainly two important scenarios i.e. Out-of-plane and In-plane direction loadings. …
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BISTABLE STRUCTURES ENABLE PASSIVE TRANSITIONS IN MOBILE ROBOTS
… inertial forces are responsible for producing snap-through. In this case, there is a direct relationship between the inertial forces and the output force of the actuators that produce the associated motions. We find that the minimum actuating force required for snap-through depends on the ratio …
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Characterization of Bistability Behavior in Unsymmetric CFRP Laminates
… in unsymmetrical [0/0/90/90] laminates through a combination of experiments and modeling. Several unsymmetrical laminates with different aspect ratios were fabricated using autoclave processing. Digital image correlation (DIC) is used to monitor laminate strains in situ during the …
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Self-folding bilayers: Mechanistic design principles for programmable and on-demand shape reconfiguration
… morphing have been established and validated through a combination of nonlinear finite element modeling and experiments with cross-linked polymeric systems. Several classes of structures such as hemispherical domes, convex regular polygons, star-shaped planar bilayers and geometries with …
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Analysis of Instabilities in Microelectromechanical Systems, and of Local Water Slamming
… curve. Here we study the symmetry breaking, the snap-through instability, and the pull-in instability of bi-stable arch shaped MEMS under steady and transient electric loads. We analyze transient finite electroelastodynamic deformations of perfect electrically conducting clamped-clamped beams and …
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Equilibrium of a shallow arch subjected to PZT actuators and a deadweight load
… induced strain actuation, the panel exhibits snap-through behavior under the midspan load. Induced strain distributions are determined at a constant midspan load to displace the panel to an inverted configuration in a stable manner. This adaptive structure may find application as an …
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Linear and nonlinear analysis of space trusses relative to cylindrical coordinates
… symmetric reticulated domes which exhibit snap-through instability and which were subjected to radially symmetric loads were analyzed both linearly and nonlinearly. Along with the entire structures, "pie slices" of the structures were also analyzed. Accuracy was observed by comparison of …
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On the use of impact-induced nonlinearities in limit switch design
… can be detected in coupled electrical systems through both electromagnetic and electrostatic coupling mechanisms. The dissertation concludes with a realization in a prototype microelectromechanical systems (MEMS) design in which a grazing bifurcation may trigger snap-through in a parallel plate …
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Bending, Creasing, and Snapping of Soft, Slender Structures
… soft, synthetic material that can bend, crease, snap, wrinkle in response to external stimulus like pH, humidity, electric field or swelling. If a droplet of favorable solvent is placed on top of a thin, elastomer beam, it bends drastically to accommodate the excessive swelling stress. Keeping …
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Topology Optimization of Nonlinear Elastic Structures and Compliant Mechanisms
… behavior, e.g. to design structures that exhibit snap-through behavior. Structure and compliant mechanism design problems are presented throughout the discussion.
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Design of a morphing airfoil exhibiting bi-stability using topology optimization
… using topology optimization. The goal is to use snap-through instabilities to actuate and maintain the shape of the morphing airfoil. Topology optimization has been used to distribute material over the design domain and to tailor the nonlinear response of the baseline structure to achieve the …
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Modelling of a Bio-inspired Bistable Structure for Potential Application in Fish Telemetry Tags
… characteristics of the hysteresis loop and snap-through discontinuity of the bistable structure are investigated using experimentation and finite element analysis. The finite element model is found to qualitatively replicate experimental observations. Addition- ally, geometrical and assembly …
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From a thin membrane to an unbounded solid : dynamics and instabilities in radial motion of nonlinearly viscoelastic spheres
… like rubber balloons, which may exhibit snap-through instabilities and consequent ruptures. By accounting for rate-dependence, the results of this thesis also shed light on the response of biological materials to dynamic load and the possible instabilities that can lead to injury in …
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