The purpose of this research is to evaluate certain performance characteristics of a morphing<br />wing system that uses Macro Fiber Composites (MFC) to create camber change. This<br />thesis can be broken into two major sections. The first half compares a few current MFC<br />airfoil designs to each other and to a conventional servomechanism (servo) airfoil. Their<br />performance was measured in terms of lift and drag in a 2-D wind tunnel. The results<br />showed MFC airfoils were effective but limited by aeroelasticity compared to the servo. In<br />addition, a morphed airfoil and a flapped airfoil were rapid prototyped and tested to isolate<br />the effects of discontinuity. The continuous morphed airfoil produced more lift with less<br />drag.<br />The second half of this thesis work focused on determining the ideal MFC configurations for<br />a thin wing application. Simulations were run on a thin wing with embedded MFCs such<br />that the whole wing morphed. Finite element and vortex lattice models were used to predict<br />deflections and rolling moment coefficients. Different configuration parameters were then<br />varied to quantify their effect. The comparisons included MFC location, number of MFCs,<br />material substrate, and wing thickness. A prototype wing was then built and flight tested.<br />While the simulations overestimated the wing deflection, the flight results illustrated the<br />complexity and variability associated with the MFC morphing system. The rolling moment<br />coefficients from flight were consistent with the simulation given the differences in deflection. / Master of Science

Thesis ( MTech(Mechanical Engineering))--Cape Peninsula University of Technology, 2011 / This study deals with the development of aero morphing reinforced composite materials embedded with NiTi alloys. It is shown that the composite materials can be manufactured using resin infusion process to produce better mechanical properties such as tensile strength and material stiffness. These composite materials are modelled experimentally using temperature and time parameters. The object of the modelling is to determine the effect of process temperature on the smart material alloy (SMA). As a result, a composite structural designer would now possess an added dimension in optimising material design. In addition, the study is conducted to analyse the structural behaviour of composite materials when embedded and when not embedded with NiTi alloys. The analysis is constrained to the evaluation of material tensile strength and stiffness upon performance of composite structures. A macro mechanical approach is employed to perform the analysis in specimens with different fibre orientation [0°, 45° and 90°]. The estimation of tensile strength and stiffness parameters is based on the characteristics obtained from a macro mechanical approach. The orientation which posses the best material properties is selected to embed NiTi alloys. The experimental results of unembedded specimens are validated with the application of micromechanics equations and an Ansys software finite element modelling tool. There is fair agreement between the finite element simulation of macro mechanical test of the specimens and the measured experimental results. Although the macro mechanical approach is found to be successful, it is imperative to characterise the material interface strength of embedded specimens using a pull out test. The pullout test showed to some great extent the properties of reinforced composite embedded with NiTi alloys.

Morphing aircraft are envisioned to have multirole capability where the ability to change shape allows for adaptation to a changing mission environment. In order to calculate the properties of many wing configurations efficiently and rapidly, a model of a morphing aircraft is needed. This paper develops an aerodynamic model and a dynamic model of a morphing flying wing aircraft. The dynamic model includes realistic aerodynamic forces, consisting of lift, drag, and pitching moment about the leading edge, calculated using a constant strength source doublet panel method. The panel method allows for the calculation of aerodynamic forces due to large scale shape changing effects. The aerodynamic model allows for asymmetric configurations in order to generate rolling and yawing moments. The dynamic model calculates state information for the morphing wing based on the aerodynamic forces from the panel method. The model allows for multiple shape changing degrees-of-freedom for the wing, including thickness, sweep, dihedral angle, and chord length. Results show the model provides a versatile and computationally efficient tool for calculating the aerodynamic forces on the morphing aircraft and using these forces to show the associated states.

Thesis (M. Phil.)--University of Hong Kong, 1999. / Includes bibliographical references.

Morphing aircraft offer many benefits. However, the design of stiff yet flexible structures still provides many obstacles to fully exploring and realizing morphing structures. Due to this, many morphing challenges remain open. Topology optimization is a type of structural optimization that optimizes the material layout of a structure based on imposed boundary conditions and load paths. This type of optimization is promising for solving morphing design challenges but many of the optimized structures are not suited for traditional manufacturing and material arrangements. Multi-material additive manufacturing is an emerging technology that can produce a single structure with many different materials integrated in custom geometries. This could be the solution to realizing topology optimized structures. Despite the rich amount of current research in morphing aircraft, many challenges still remain open and topology of morphing structures could provide the solution to these morphing challenges. / Master of Science

Thin unsymmetric carbon fiber reinforced polymeric(CFRP) composite laminates are examined for use of morphing structures using piezoelectric actuation. During fabrication, unsymmetric laminates are able to deform to more than one post-cure room temperature shape. Thin cross-ply laminates will deform to a cylindrical post-cure room temperature shape while thicker non-cross-ply laminates will deform to a saddle shape. Predictions of the deformed post-cure shape will be made by modeling the cure process using analytical and numerical. These models will then serve as expectations for experimental tests. Modeling the fabrication process allowed for characterizing important data such as residual stresses from the cure process, room temperature shapes, and bi-stability of the CFRP composite laminates all of which are needed to accurately model morphing structures. Cross-ply laminates will deform to a symmetric cylindrical shape, cylindrical shape I, after the cure process. Non cross-ply laminates will deform to a non-uniform saddle shape after the cure process. These post-cure room temperature deformation shapes can be used as morphing structures by applying a force large enough to create ”snap” through to the other cylindrical shape, cylindrical shape II. A piezoelectric actuator, bonded to the deformed room temperature shapes, is used to generate this ”snap through force”. Experimental verification was done by fabricating the CFRP composite laminates and comparing the post cure room temperature shapes to the analytical and numerical fabrication models. For morphing structures, experimental verification was done by actuating the piezoelectric actuator and comparing the deformation of cylindrical shape II to analytical and numerical piezoelectric models.

No description available.

An investigation into an adaptable morphing concept for enhancing aircraft control and performance is described in this thesis. The impetus for the work was multi-legend. Initially, the work involved identifying and optimizing winglets on a swept wing baseline configuration to enhance the controllability and aerodynamic efficiency of unmanned aerial vehicles. Moreover, the other objective was to develop a realistic skin for a morphing aircraft concept that would allow subtle, more efficient shape changes to improve aircraft efficiency. In this regard, preliminary computations were performed with Athena Vortex Lattice modelling in which varying degrees of twist, swept and dihedral angle were considered. The results from this work indicated that if adaptable winglets were employed on small scale UAVs improvements in both aircraft control and performance could be achieved. Subsequent to this computational study, novel morphing wing and/or winglet mechanisms were developed to provide efficient shape changing as well as to develop a novel alternative method for a morphing skin. This new technique was numerically optimized in ANSYS Mechanical, experimentally investigated in a wind tunnel, and also compared with a baseline aileron configuration. Afterwards, flight testing was performed with an Extra 300 78 inch remote controller aircraft with the results being compared against existing fixed wing configurations. After evaluating numerical results, from various winglet configurations investigated in AVL, selected cases were found to provide good evidence that adaptable winglets, through morphing, could provide benefits for small scale aircraft control and performance as well as offering an acceptable alternative aircraft control methodology to the current discrete, 3-axis control philosophies. Using ANSYS Mechanical for structural analysis, rib configurations were also optimised in terms of weight, stress, and displacement, as well as required twist deformation magnitudes (±6° of twist achieved). Furthermore, the skin was found to be rigid with a low rate of surface wrinkling promoting a low drag surface. Ultimately, the viability of this novel concept mechanism was validated through flight testing with similar roll authority achieved compared to traditional aileron configuration. Finally, a morphing concept also provided potential shape changing performance with smooth aerodynamic surface finish. Leading to the possibility of the concept is being a viable skin for morphing application.

No description available.

This thesis presents an efficient and biologically informed 3D human body morphing technique through data-driven alteration of standardized 3D models. The anthropometric data is derived from a large empirical database and processed using principal component analysis (PCA). Although techniques using PCA are relatively commonplace in computer graphics, they are mainly used for scientific visualizations and animation. Here we focus on uncovering the underlying mathematical structure of anthropometric data and using it to build an intuitive interface that allows the interactive manipulation of body shape within the normal range of human variation. We achieve weight/gender based body morphing by using PCA. First we calculate the principal vector space of the original data. The data then are transformed into a new orthogonal multidimensional space. Next, we reduce the dimension of the data by only keeping the components of the most significant principal vectors. We then fit a curve through the original data points and are able to generate a new human body shape by inversely transforming the data from principal vector space back to the original measuring data space. Finally, we sort the original data by the body weight, calculating males and females separately. This enables us to use weight and gender as two intuitive controls for body morphing. The Deformer program is implemented using the programming language C++ with OPENGL and FLTK API. 3D and human body models are created using Alias MayaTm.