Hide/Show Apps

Synthesis, analysis and design of a novel mechanism for the trailing edge of a morphing wing

Download
2018
Şahin, Harun Levent
In this thesis, synthesis, analysis and design of a novel scissor-structural mechanism (SSM) with a four-bar (FB) linkage for the trailing edge of a morphing wing has been presented. The SSM, which is deployable, is created via combination of various scissor-like elements (SLEs). In order to provide mobility requirements, a FB linkage is assembled to the proposed SSM. The FB linkage is synthesized and optimized in order to give the structure required torque with a complete rotation. The SSM is designed with a novel kinematic synthesis concept in order to follow the airfoil camber with minimum design error. In this concept, various types of SLEs are assembled together to provide the desired airfoil geometries. The types (translational, polar), the number of SLEs, their orientations with respect to centerline of the airfoil and their distribution frequencies over the chord length are the design parameters, which allow designers to achieve all the possible geometric shapes. The combination rule is optimized in order to satisfy desired airfoil shapes with minimum design error as possible. Moreover, the position, velocity and acceleration analyses of the SSM have also been conducted. In order to prove aerodynamic efficiency of newly created airfoil geometries and obtain pressure distribution over the airfoil, 2D aerodynamic analyses have been done with the package program XFOIL. The flow characteristics used for the analysis are determined by the flight envelope of a generic UAV. Obtained pressure distribution is applied as the lumped force on the joints. By assigning the approximate link masses and mass centers, the dynamic force analysis of the mechanism has also been performed in order to estimate the required torque to drive the synthesized SSM.