Design of a variable-span morphing wing

• Autor(a) principal: Mestrinho, João Rafael da Conceição
• Data de Publicação: 2009
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.6/2048

The present work focuses on the study, design and validation of a variable-span morphing wing to be tted to the UAV \Olharapo". Using an optimization code, which uses a viscous two-dimensional panel method formulation coupled with a non-linear liftingline algorithm and a sequential quadratic programming optimization routine, na aerodynamic analysis is performed to estimate the optimal values of wing span which ensure minimum drag across the ight speed envelope. The UAV ies in a relatively short speed range - from about 12 m/s to 30 m/s. Near its maximum speed it is possible to obtain a 20% drag reduction with the variable-span wing in comparison with the original xed wing. A stability analysis is also performed to estimate the roll rate available with asymmetric span control. The variable-span wing matches the aileron in terms of roll power and maximum roll rate. It is concluded that roll control is possible with asymmetric span control. A new electro-mechanical actuation mechanism is developed using a simple and cheap rack and pinion system. The wing model is designed with graphical CAD/CAM tools and then a full scale model is built for bench testing the wing/actuator system. The concepts used on the morphing wing for both xed and movable part are considered simple and e ective. The actuation concept is also feasible but needs improvements in the attenuator. A powerful servo is also needed to more easily deploy the wing. Some future modi cations at structural level and ideas for an in-flight automatic span controller are also presented.