Analysis & Manufacturing of Composite Airframe for Uniaxial Unmanned Aerial System (UAS)

该项目的工业合作伙伴Airvinci正在开发一种带管道风扇的同轴旋翼机，有载人和无人两种类型。增加旋翼机的有效载荷比例是AirVinci的主要目标，因为它将提高燃油经济性和机动性。因此，根据FAR Part 27的规定，Airvinci需要一种符合所有规定的复合材料机身。复合材料机身将需要进行优化，以承受所有飞行载荷以及着陆阶段的冲击载荷消散。该项目的两个主要目标是：1.用复合材料等效物直接替换现有的钢结构空间框架。2.设计优化的减震复合材料机身因此，研究工作将集中在以下方面：1.非线性显式动力结构分析根据FAR Part 27标准，机身需要具有耐撞性。因此，它将被要求显示机身在动态载荷下不会显著变形或回弹。传统的有限元模型使用线性求解器进行静态分析和小位移。为了准确估计机体的耐撞性和着陆滑板的能量吸收能力，需要一个非线性模型和显式模型。非线性模型将允许进行更复杂的故障模式和动态分析。显式求解器将允许模拟着陆。2.设计优化复合材料的各向异性特性允许大量定制以适应设计载荷。利用有限元分析软件中可用的组件组合，可以确定各层的方向以及它们的堆叠顺序。由此产生的设计也将针对制造进行优化，以避免复杂的工具。

The project industrial partner, Airvinci, is developing a coaxial rotorcraft with a ducted fan in both manned andunmanned types. Increasing the payload fraction of the rotorcraft is Airvinci's major objective as it wouldincrease fuel economy and maneuverability. As a result Airvinci desires a composite airframe that meets allregulations according to FAR part 27. The composite airframe will need to be optimized to endure all flightloads as well as impact load dissipation during the landing phase. The two main objectives of the proposedproject are:1.Direct Replacement of an existing steel spaceframe with composite equivalent.2.Design of an optimized impact reducing composite airframeThe research effort will therefore focus on the following:1.Non-linear Explicit Dynamic Structural AnalysisThe airframe will need to be crashworthy according to FAR part 27 standards. Therefore, it will be required toshow that the airframe will not deform significantly or will springback under dynamic loads. Traditional FEmodels utilize linear solvers for static analysis and small displacements. For an accurate estimation towards theairframe's crashworthiness and energy absorbing capabilities of the landing skids, a Non-linear model explicitmodel will be required. The nonlinear model will allow for more complex failure modes as well as dynamicanalysis. An explicit solver will allow for simulating the landing.2.Design OptimizationThe anisotropic properties of composites allow for a great deal of tailoring towards the design loads. Using acombination of the packages available in ANSYS it is possible to determine the directions of the plies as wellas their stacking sequence. The resulting design will also be optimized for manufacturing to avoid complextooling.