air vehicle's endurance (sec.) i incidence angle (radians) I x mass moment of inertia about x-axis (Kg.m 2 ) L lift force (N) m number of wing stations solved M x moment about x-axis (N.m) n vortex location q dynamic pressure (Pa) Q amount of electric charge stored in battery R air vehicle's range (m) ABSTRACTThe aerodynamic design optimisation of a Micro Air Vehicle (MAV) wing is performed to obtain the optimal anti-symmetric wing twist distribution for the roll control of the MAV's wing instead of using conventional ailerons. This twist distribution should produce minimum induced drag and achieve a better roll response. The implementation of several anti-symmetric load distributions such as the half lemniscates and the Horten distributions is studied leading to an initial solution for the optimal distribution that could achieve better roll requirements. Multhopp's method based on Prandtl's classical lifting line theory is used for the determination of the spanwise load distribution required during the optimisation process. The optimisation process is based on the modified feasible directions gradient based optimisation algorithm implemented in the optimisation system, VisualDOC, given by Dr. Garret Vanderplaats. The proposed optimisation process is applied to the 'BARQ'developed MAV which has successful flight in July 2009. NOMENCLATUREa o aerofoil lift curve slope (rad -1 ) AR aspect ratio

The aerodynamic shape optimisation of a micro air vehicle (MAV) wing is performed to obtain the basic wing geometrical characteristics which produce the maximum range and endurance requirements. Multhopp's method based on Prandtl's classical lifting line theory is used for the determination of the spanwise load distribution required during the optimisation process. The obtained lift and drag characteristics are used for the derivation of the range and endurance equations of an electrically driven micro air vehicle. The optimisation process is based on the modified feasible directions gradient based optimisation algorithm. Results are validated using wind tunnel measurements showing very good agreement. Results are also compared with solutions to the Navier-Stokes equations obtained with ANSYS-CFX finite elements using different turbulence models. These include the k-ε and the shear stress transport (SST) models as well as the Reynolds stress model.

Reissner's, stress-based, shear deformation plate theory is chosen to approximate the stress field for balanced symmetric laminates. The longitudinal stresses are assumed to vary linearly along the plate thickness. In fact, we may view the purpose of this work as an examination of effectiveness of mathematical laminate models in which the response is defined in terms of force and moment resultants. Average stiffness moduli are considered to characterize the laminate properties. The accuracy and the range of application of the present approach are proved for laminated plate:1-in cylindrical bending and 2-simplly-supported with different thickness, for which elasticity solutions exist. The paper presents the first step of validation of the developed theory. The cylindrical bending of symmetric cross-ply laminated plates subjected to sinusoidal loading is investigated. Results from the present theory are compared with those from exact solutions and other known theories as well.

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The wing of an UAV plays an important role in the vehicle behavior. In order to understand its main influences, a dedicated test rig was designed and realized to load the composite wing in the bending configuration. This study describes the details of a numerical and an experimental investigation done with the aim to identify the stiffness characteristics of a composite wing structure of an Unmanned Aerial Vehicle (UAV). The wing was divided into discrete span-wise stations. Wooden bolted clamps were placed along the upper and lower surfaces of the wing at each station, to support the applied load and the displacement transducers. The wing was suspended and secured horizontally (at the wingfuselage connection base) in a rigid test stand in an orientation similar to the familiar cantilever beam. A single weight was applied individually, at each station to stress the wing in elastic yield, as in real conditions. Displacement transducers were installed to measure the vertical displacements of the entire wing, and monitor any motion of the overall airframe. During the measurement procedures (loading and unloading) were conducted on the specified stations, and repeated 10 times, the mean value of the measurements was obtained. A detailed numerical model of the composite wing was developed using of the finite element method in order to reproduce the experimental experiences. Numerical and experimental results were compared to validate the model of the composite wing. All the obtained parameters are mainly being used in a development process of UAV behavior.