面向结构形状控制的压电纤维复合薄膜驱动器布局方式与控制参数协同优化设计

Integrated Design Optimization of MFC-layout Form and Control Parameters for Morphing Structural Shapes

能够根据工作环境改变翼面形状的自适应变形能力是未来航空、航天飞行器结构设计追求的重要目标。研究驱动器布局方式以及控制参数的设计技术是实现该目标的关键。以压电纤维复合薄膜(Macro fiber composites,MFC)作为驱动器,研究在一定数量的MFC驱动器条件下,通过驱动器布局与控制参数的协同设计,以实现类翼面平板结构具有理想形状的最优控制设计方法。以驱动器的铺设位置、铺设角度、层数、对称性以及控制电压为设计变量,以驱动器的击穿电压、铺设位置限制等为约束,建立多参数下的协同优化设计模型。数值算例以类机翼平板的弯曲、扭转、弯扭型面作为理想型面,以实际型面与理想型面在81个参考点位置的均方差为评价指标,设计获得弯曲、扭转和弯扭组合型面的均方差分别为9.977×10–5、4.394×10–4和5.308×10–4,实现了较高的变形控制精度。研究了驱动器数量对变形精度的影响,制作了具有6个驱动器的类翼面平板结构测试平台,仿真与试验结果高度吻合,从而验证了所提出的驱动器布局与控制电压协同优化设计模型的有效性和可行性。

One of the key objectives in the structural design of aircraft and spacecraft is the capability of accurate shape morphing that can meet various operational and environmental requirements for enhanced performance of the flight vehicles. The key to realize such capability could be dependent on the research into the design methods for finding the optimum layout of actuators and the associated controlling parameters. An integrated design optimization method for morphing a thin plate was presented with the shape like an aircraft wing via a concurrent design of the layout for given number of macro fiber composite （MFC）actuators and their relevant controlling parameters without the consideration of the external loads. An integrated optimization model is developed with the goal of minimizing the deviation between a required shape and an actual one through optimizing actuator locations, angles, layer number, symmetry and control voltages subject to the constraints, such as the breakdown voltage of the MFC and the geometrical limit of MFC-actuators. In the numerical examples, considered are three desired shapes of a thin plate with the shape like an aircraft wing, namely, bending, twisting and bending-twisting shapes. A total of 81 uniformly distributed observation points are used to implement shape morphing via evaluating the standard deviation between a desired shape and an actuated one. The optimal standard deviations for the bending, twisting, and bending-twisting shapes are 9.977×10^–5, 4.394×10^–4 and 5.308×10^–4, respectively, which indicate a good accuracy for these multi-parameter shape morphing. Test panels of idealized control surfaces were prepared and experimental setup was constructed. The test results show a good correlation between the desired shape and the actuated one by using the present MFC-layout and controlling parameters, which in turn validates the effectiveness and feasibility of the proposed method.