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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 21 for “"Macro-Fiber Composite"”.
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Using Macro-Fiber Composite Actuators for Aquatic Locomotion
… for an autonomous underwater vehicle using Macro-Fiber Composite (MFC) actuators. The swimming system draws inspiration from the motion of carangiform fish, which limit their body motion while rapidly oscillating their caudal tail fin. The foundation for the bio-inspired swimming system is …
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Electrical Properties of Macro-Fiber Composite Actuators and Sensors
Piezoceramic fiber composite (PFC) actuators and sensors offer many advantages over conventional monolithic piezoceramic devices. Conformable, durable and, when equipped with interdigitated electrodes (IDEs), more responsive than regular monolithic devices, PFCs promise to revolutionize the …
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Macro Fiber Composite Actuated Unmanned Air Vehicles: Design, Development, and Testing
… and fabricate in a repeatable fashion on thin, composite-wing micro-air-vehicles. Assembly is complex and time consuming. A type of piezoceramic composite actuator commonly known as Macro Fiber Composite (MFC) is used for wing morphing. The actuation capability of this actuator on fiberglass …
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Macro Fiber Composite Actuated Control Surfaces with Applications Toward Ducted Fan Vehicles
… morphing, a piezoelectric device known as Macro Fiber Composites is used. These devices are embedded in the skin of the vehicles control surface, and when actuated, they cause the control surface to increase or decrease camber. This thesis describes experiments that were performed to …
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Integration of Macro-Fiber Composite Material on a Low Cost Unmanned Aerial System
… a simulation environment for mechanical and Macro-Fiber Composite (MFC) actuated ailerons in a Skywalker 1880 UAV using model reference adaptive control law. This work will contribute to a baseline model for the research and development of future UAV with morphing control surfaces up to a …
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Finite Element Modeling of Macro Fiber Composite Actuators with Application to Wing De-icing
… technique is studied in which lightweight Macro Fiber Composite (MFC) actuators are used to break the adhesive bond between the leading edge of a wing and an accumulated ice layer. The concept for this technique relies on the fact that when a structure is excited at its natural frequencies, …
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Dual Mode Macro Fiber Composite-Actuated Morphing Tip Feathers for Controlling Small Unmanned Aircraft
… control surfaces and uses for smart materials. A Macro Fiber Composite (MFC), a smart material, takes advantage of the piezoelectric effect and provides an attractive alternative actuator to servos in the Small Unmanned Aerial Systems (SUAS) regime of flight. This research looks to take MFC …
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Aerodynamic and Electromechanical Design, Modeling and Implementation Of Piezocomposite Airfoils
… and sensing over a wide range of frequencies. A Macro-Fiber Composite is a type of piezoelectric device that offers structural flexibility and high actuation authority. A challenge with piezoelectric actuators is that they require high voltage input; however the low power consumption allows for …
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Dynamics and Control of Membrane Mirrors for Adaptive Optic Applications
… and a membrane strip augmented with multiple macro-fiber composite bimorphs. The later structure is studied under two actuation configurations. In the first configuration, both actuators act in bending. In the other configuration, one actuator acts in bending and the second acts in tension. …
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Nonlinear Mechanical and Actuation Characterization of Piezoceramic Fiber Composites
… However, actuators with piezoceramic fibers and interdigitated electrodes have risen to the forefront of the intelligent structures community due to their increased actuation capability. However, their fiber-reinforced construction causes them to exhibit anisotropic piezomechanical …
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Characterization of Oscillatory Lift in MFC Airfoils
… of an airfoil with an oscillatory morphing, Macro-fiber composite (MFC) trailing edge. Correlation of the airfoil lift with the oscillatory input is presented. Modal analysis of the test airfoil and apparatus is used to determine the frequency response function. The effects of static MFC …
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Design, Fabrication, and Testing of a Proprioceptive Electroadhesion Pad for Space Applications
… to obtain optimum surface adhesion, the use of Macro Fiber Composite (MFC) actuators were embedded on the electroadhesion pad. Fabrication methods involving the use of chemical etching process on copper clad composites were used in order to test the pads and determine the level of adhesion …
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Use of Piezoelectric Actuators to Effect Snap-Through Behavior of Unsymmetric Composite Laminates
… 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 morphing structures, one or more piezoelectric …
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High Frequency Modeling and Experimental Analysis for Implementation of Impedance-based Structural Health Monitoring
… point. Preferred excitation frequencies for macro-fiber composite (MFC) active sensors are statistically determined for a long composite boom under development for use in rigidizable inflatable space structures.
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Desarrollo de dispositivos recolectores de energía de fuentes vibratorias
… en los extremos libres y una lámina de MFC (Macro Fiber Composite) adherida a una de las vigas. Como aspecto fundamental del dispositivo se destaca la capacidad de generar energía en condición resonante y no resonante en un rango de baja frecuencia de operación; este comportamiento se debe a …
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MEMS Technologies for Energy Harvesting and Sensing
… we also fabricated the first magnetoelectric macro fiber composite. This device also employs a novel low temperature metallic bonding technique to fuse the magnetostrictive layer to the piezoelectric layers. A special low viscosity epoxy enabled the joining of the flexible circuit to the …
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Design, Simulation, and Wind Tunnel Verication of a Morphing Airfoil
… achieved through the use of piezoelectric Macro Fiber Composites (MFCs). These devices exhibit low power draw but excellent bandwidth characteristics. This thesis provides a background in the 2D analytical and computer modeling tools and methods needed to design and characterize an …
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Macro-Fiber Composites for Sensing, Actuation and Power Generation
The research presented in this thesis uses the macro-fiber composite (MFC) actuator that was recently developed at the NASA Langley Research Center for two major themes, sensing and actuation for vibration control, and power harvesting. The MFC is constructed using piezofibers embedded in an epoxy …
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Crack Detection in Aluminum Structures
Structural health monitoring (SHM) is the process of using measurements of a structure's response to known excitations and trying to determine if damage has occurred to the structure. This also fits the description of non-destructive evaluation (NDE). The main difference is that NDE takes place …
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A comparison of power harvesting techniques and related energy storage issues
… bimorph. Next, an investigation into new active fiber composite materials and macro fiber composite devices utilizing the d31 coefficient is performed in comparison to a monolithic piezoelectric bimorph. The information gathered here was used to design a two bimorph device termed the mobile …
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