本文通过优化的方式设计了一种具有较高变形精度的适用于变体飞行器的柔性后缘变弯度装置。该装置通过结构的弹性变形传递力和运动，包括驱动器、一体成型的蒙皮与梁结构组成。在给定的结构拓扑形状下，为了寻找到最优的驱动、结构参数，本文系统化地提出了柔性变弯度后缘的设计框架。该设计框架包括了变弯度机翼外形参数化方法、变弯度气动外形的优化设计方法和结构参数优化方法，求解结构变形时考虑了几何非线性大变形，采用最小平方误差和考虑空间顺序的Fréchet距离来衡量后缘真实变形与目标变形之间的相似性。对比研究表明，最小误差距离不能捕捉到局部的噪声，而Fréchet距离可以很好地控制最大的变形误差，所需迭代次数较少，并能获得整体变形精度较高的结果。数值仿真验证了所提出的优化方法的有效性。本文对多种具有不同拓扑的初始结构进行参数优化，最大能提高91%变形精度。最后，利用增材制造技术实现了柔性变弯度后缘翼段，该部件具备下偏22.5°，上偏7.5°的变形能力。
In this paper, optimal size parameters are explored for a compliant morphing trailing edge device with high deformation accuracy. This device transmits force and movement through elastic deformation, and includes an actuator, and an integral skin-beams structural. A systematical design framework is proposed in order to find the optimal actuating and structural size parameters for a morphing trailing edge under a given structural topology. This framework consists of a shape parameterization for morphing trailing edge wing, aerodynamic shape optimization tool, and structural parameter optimization methods. Geometric nonlinearity is considered when solving structural large deformation. Comparative studies have shown that the Least Square Error distance cannot capture the local disturbance, while the Fréchet distance can well control the maximum deformation error, needs fewer iterations, and can obtain better results with higher overall deformation accuracy. Numerical simulations verify the effectiveness of the proposed optimization method. The optimal design of four initial structures with different topology are obtained, with a maxi-mum improvement for deformation accuracy of 91%. Finally, a prototype of compliant morphing trailing edge is realized through additive manufacturing, which has a deformability of 22.5° downward and 7.5° upwards.
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