This study presents a camber morphing concept as an alternative to existing plain flap or aileron type hinged control surfaces used in wings. Structural aspects of the concept are investigated with static nonlinear finite element analyses by using MSC Nastran. In order to assess the aerodynamic characteristics / CFD based 2D solutions are obtained using ANSYS Fluent. The camber morphing concept is applied to the full scale hingeless control surface and implemented in the adaptive camber wing. Hingeless control surfaces and adaptive camber wing are manufactured and changes made in manufacture stages are incorporated into finite element models. Finite element analyses of the wing are conducted with static and dynamic loading and comparison with experimental dynamic analyses are performed.

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An orthosis, or orthotic device is used to straighten or correct the posture of part of the body. A foot orthosis (FO) is the subject of study for this dissertation. A FO is situated between the foot and the midsole of the shoe and replaces the insole. Foot orthoses (FOs) are intended to prevent or aid in the recovery of injury by acting to redistribute pressure experienced by the plantar surface of the foot as well as cause adjustments to the relative positions of the foot's bones during standing and gait. Traditional methods for developing a FO require extensive skilled manual labour and are highly dependent on subjective input. Modern FO development methods have sought to address these issues through the use of computer driven technological advancements. Foot scanners record geometry, computer aided design (CAD) software is used to develop the FO geometry, and automated manufacturing tools are used to either fabricate the FO or fabricate a mould about which the FO can be formed. A variety of modern solutions have successfully automated the process, however, it remains highly subjective. Skilled manual labour has merely been replaced with equally subjective skilled computer labour. In particular, adjustments to the foot are made with basic deformation functions to the static surface foot models generated by modern digitizers. To improve upon this, a model that describes the mechanics and properties of the various tissues of the foot is required. Such a model will also be useful for validating and optimizing FO designs prior to fabrication through simulation of weight-bearing conditions. Given the deformable characteristics of the tissues of the foot, the finite element (FE) modeling method is appropriate. The FE foot model has become a common medical and engineering tool in recent years. Its application, however, has primarily been limited to research as few clinical applications warrant the development cost. High cost stems from the MRI or CT scan and the skilled labour required to assemble the model for FE analysis. Consequently, the FE modeling approach has previously been out of reach for the application of FO development. The solution proposed and implemented was to map a detailed generic FE foot model to an inexpensive surface scan obtained from a modern digitizer. The mapping accurately predicted anatomical geometry and resulted in simulation models that can be used in the FO development process first to carry out postural adjustments prescribed by a practitioner and second in a validation step where a FO design can be tested prior to fabrication. In addition to simulation tools, novel complementary tools were developed for designing and fabricating FOs. The simulation, design, and fabrication tools were incorporated into a novel, seven step FO development process. The proposed process is beneficial to FO development as it reduces the required subjective input from practitioners and lab technicians and allows for the validation of potential FO designs prior to fabrication. Future work is required to improve computational efficiency of the FE foot models and to fully automate the process to make it commercially viable. In addition to FOs, the proposed approach also presents opportunities for improving other orthoses and prostheses for the human body.

This study is concerned with the design and development of a novel wing for UAVs that morphs seamlessly without the use of complex hydraulics, servo motors and controllers. The selected novel design is characterized by a high degree of flight adaptability and improved performance with a limited added weight. These characteristics were attained through the use of shape memory actuators in an antagonistic fashion. Unlike compliant actuators, the antagonistic setup requires the thermal energy to deform the wing but not to maintain its deformed shape. Structural analysis based upon safety factors specified by FAR23 standards and aerodynamic analysis using FLUENT were conducted on the novel design to validate its suitability as a viable wing for UAVs. In addition, thermal conditioning of the shape memory actuators was conducted using a specially designed programmable controller. This thesis does not concern itself with the design of a skin that accommodates the shape changes.

This study is concerned with the design and development of a novel wing for UAVs that morphs seamlessly without the use of complex hydraulics, servo motors and controllers. The selected novel design is characterized by a high degree of flight adaptability and improved performance with a limited added weight. These characteristics were attained through the use of shape memory actuators in an antagonistic fashion. Unlike compliant actuators, the antagonistic setup requires the thermal energy to deform the wing but not to maintain its deformed shape. Structural analysis based upon safety factors specified by FAR23 standards and aerodynamic analysis using FLUENT were conducted on the novel design to validate its suitability as a viable wing for UAVs. In addition, thermal conditioning of the shape memory actuators was conducted using a specially designed programmable controller. This thesis does not concern itself with the design of a skin that accommodates the shape changes.

The past twenty years have seen the successful characterization and computational modeling efforts by the smart materials community to better understand the Shape Memory Alloy (SMA). Commercially available numerical analysis tools, coupled with powerful constitutive models, have been shown to be highly accurate for predicting the response of these materials when subjected to predetermined loading conditions. This thesis acknowledges the development of such an established analysis framework and proposes an expanded design framework that is capable of accounting for the complex coupling behavior between SMA components and the surrounding assembly or system. In order to capture these effects, additional analysis tools are implemented in addition to the standard use of the non-linear finite element analysis (FEA) solver and a full, robust SMA constitutive model coded as a custom user-defined material subroutine (UMAT). These additional tools include a computational fluid dynamics (CFD) solver, a cosimulation module that allows separate FEA and CFD solvers to iteratively analyze fluid-structure interaction (FSI) and conjugate heat transfer (CHT) problems, and the addition of the latent heat term to the heat equations in the UMAT to fully account for transient thermomechanical coupling. Procedures for optimizing SMA component and assembly designs through iterative analysis are also introduced at the highest level. These techniques are implemented using commercially available simulation process management and scripting tools. The expanded framework is demonstrated on example engineering problems that are motivated by real morphing structure applications, namely the Boeing Variable Geometry Chevron (VGC) and the NASA Shape Memory Alloy Hybrid Composite (SMAHC) chevron. Three different studies are conducted on these applications, focusing on component-, assembly-, and system-level analysis, each of which may necessitate accounting for certain coupling interactions between thermal, mechanical, and fluid fields. Output analysis data from each of the three models are validated against experimental data, where available. It is shown that the expanded design framework can account for the additional coupling effects at each analysis level, while providing an efficient and accurate alternative to the cost- and time-expensive legacy design-build-test methods that are still used today to engineer SMA actuated morphing aerostructures.

Orientador: Leo Pini Magalhães / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-09T21:26:28Z (GMT). No. of bitstreams: 1 Schroeder_GreyceNogueira_M.pdf: 4292885 bytes, checksum: 37f5409f283c62fcb20cf1456b55943f (MD5) Previous issue date: 2007 / Resumo: O morphing de imagens é uma transformação que mapeia uma imagem em outra, alterando tanto a sua forma quanto as suas intensidades. Esta transformação possui diversas aplicações em imagens médicas e especialmente na indústria de entretenimento. Este trabalho objetiva, através do uso de morphing, apresentar um protótipo para a simulação de envelhecimento de faces frontais, utilizando um método chamado Funções de Base Radial (RBF) juntamente com um modelo quantitativo para expressar o processo de envelhecimento no rosto humano. O protótipo trabalha com imagens de pessoas a partir de 20 anos e realiza o envelhecimento até no máximo 70 anos. Além disso, o trabalho apresenta uma revisão bibliográfica sobre as principais técnicas de morphing e sobre o que já foi realizado sobre simulações computacionais de envelhecimento facial por imagens / Abstract: Image morphing is a transformation that maps one image into another, altering both its shape and intensities. These types of transformation have a wide range of applications in medical imaging and, specially, in entertainment industry. This work attempts to present a prototype for aging simulation on frontal face images, using a method of morphing called Radial Basis Functions (RBF) together with a quantitative model for expressing human aging. The prototype works with images from people with 20 years old up and performs the aging up to 70 years. Moreover, the work presents a bibliographical revision on the main techniques of morphing and on the state of the art on computational simulations of image face aging / Mestrado / Engenharia de Computação / Mestre em Engenharia Elétrica

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<p>A key aspect of color change is altering perceived value or intensity. This dissertation presents a methodology to achieve value change through mechanical means via the deflection of bistable structures. We create the Mechxel, two methods of mechanical pixel-based, reversible color change using 3D printed switchable multistability and bistable switch panels that augment the projected area a viewer perceives which enables the creation of image and character tessellation.</p> <p>Switchable multistability (SMS) arises from the combination of pre-strain and shape memory, allowing us to access multiple elastically programmed shapes at elevated temperatures with fast morphing and low actuation forces, while retaining high stiffness at room temperature. We design and manufacture SMS Mechxels using fused deposition modeling (FDM) 3D printing on the Ultimaker 3D printer in a bilayer layup of polylactic acid (PLA) with a [90/0] print direction while iteratively miniaturizing the physical size to enhance the resolution while also reducing the size of the overall tessellated display. Leveraging SMS properties programmed into each Mechxel, the projected area to a viewer will vary between the unit’s stable states, creating a difference in perceived value of coloration due to changes in area. To ease the tessellation process, we also introduce a tessellation user interface that maps images to their tessellated equivalent to reduce tessellation trial and error. This interface also calculates the number of Mechxels required in their respective states and the final physical size of the display. We then carry out image processing to justify this change in value between stable states and run preliminary optical character recognition.</p> <p>Inspired by mechanical bistable mechanisms, the bistable switch Mechxels utilize changes in a surface’s projected area to a viewer via changes in the angle of a bistable tile using a 5-by-5 grid for character replication and display. Comprising of three main components – two bistable switches, a colored tile and a base, design considerations were made to create an easy to assemble and replaceable 3D printed grid system that could be interacted with by audiences or easily electromechanically actuated. Using pixel-by-pixel comparisons and Sorensen-Dice coefficient, characters using the typeface Silkscreen were documented on these tiled grids yielding high similarity and low error when compared to their digital reference images in various positions and orientations. We also experiment with transitional waves as a promising means of actuation to change the Mechxel between their stable states.</p> <p>The Mechxels considered in this research introduce a new means of purely mechanical color change, character, and image display either leveraging the elastic properties of shape memory polymers (SMPs) or bistable mechanisms. With potential applications in passive morphing architecture, adaptive camouflage, and interactive aesthetic, Mechxels opens the door to limitless design possibilities through a new perspective into color change.</p>