基于甲虫后翅仿生的微小型飞行器柔性可折叠翼设计及动力学研究

Hind wing of beetles (Coleoptera) has bigger folding rate, and the behavior of folding wing’s folding/unfolding and flapping relates to the interaction of the wing’s material, structure motion and load-carrying capability. The flexible folding wing has an important application prospect in the field of imitation insect air vehicle with flapping wing. The control augmented -structural synthesis and kinetic of flexible folding wing based on Electroactive Polymer (EAP) are studied in this project. In this study, the experimental and finite element simulation methods are used to quantitatively analyze folding and unfolding movement of micro flexible folding wings with multi degree of freedom. The bionic folding mechanism for flexible folding wing with semi-active by elastic hinge is designed by the bionic method. The dynamic model of unfolding and folding process is established by Lagrange method, and the numerical simulation and analysis of dynamic characteristics are conducted. The inherent laws of folding and unfolding performance and some factors, such as the structural parameters of flexible folding wing and the stiffness of elastic hinge, are explored. Based on aerodynamic model of three-dimensional unsteady vortex lattice method，the flapping dynamical model of the folding wing is established. The coupling effects of the whole flapping movement，relative rotation between the wing, flexible deformation，pneumatic resistance，the structure and physical parameters of folding wing and elastic hinge are studied. The results will provide a novel way for the micro-air vehicle.

鞘翅类甲虫后翅拥有较大的折叠率，甲虫后翅的展开、折叠及飞行行为涉及翼面的材料、结构、运动和受力等多因素作用。仿甲虫后翅折叠翼在微型扑翼飞行器领域有重要的应用前景。本项目研究基于介电型电活性聚合物（EAP）的柔性可折叠翼控制-结构一体化仿生设计及其动态特性。运用实验与有限元模拟等方法定量研究柔性折叠翼的运动特征，基于仿生设计法，提出一种依靠弹性铰链驱动的柔性折叠翼的半主动展开机构；建立折叠翼机构展开与折叠过程的动力学方程，通过动力学分析与数值仿真，探讨折叠翼的几何结构与物理参数、弹性铰链刚度等因素对折叠与展开性能的影响程度与内在规律。基于三维非定常涡格法建立折叠翼扑翼过程的空气动力学模型，结合柔性多体系统方法，研究折叠翼的几何结构与物理参数、弹性铰链参数对其扑翼过程的整体运动、各翼板间的相对转动、翼板柔性变形与气动阻力的耦合效应。研究结果将为仿甲虫微型扑翼飞行器的开发提供新思路与新方法。

自然界中，飞鸟、昆虫等扑翼飞行生物经过不断适应环境和优化选择，具有令人惊叹的飞行技巧，其在形态、运动方式、能量利用等方面有显著优点。鞘翅类甲虫后翅拥有较大的折叠率，甲虫后翅的展开、折叠及飞行行为涉及翼面的材料、结构、运动和受力等多因素作用。仿甲虫后翅折叠翼在微型扑翼飞行器领域有广泛的应用前景。项目通过分析甲虫后翅折叠翼的折叠、展开与扑翼运动的特征，进行柔性折叠翼仿生设计，提出一种多自由度柔性折叠翼的控制-结构一体化设计实现方案。研究了IPMC弹性铰链特性，进行折叠翼折叠性能分析。建立折叠翼的折叠率计算数学模型，获得不同折痕角度下，翅翼的面积折叠率。采用多柔体系统动力学方法和流体力学相结合的方法，建立可折叠翼的展开折叠、展开与扑翼过程的动力学方程。利用ADAMS软件建立折叠翼机构的刚柔动力学仿真模型，进行运动仿真分析，分析两者运动特性，得出了刚性翅翼和柔性翅翼在折叠过程中的二面角和扭矩变化规律，改进翅翼的折叠性能。研究折叠翼的几何结构与物理参数、弹性铰链参数对其刚体运动、柔性变形与气动阻力的综合影响及其耦合效应。采用双向流固耦合（FSI）数值模拟方法，对仿生折叠翼飞行器的前飞过程和滑翔过程的气动性能建模与仿真分析。对不同运动参数下的扑翼前飞过程进行数值模拟，对不同条件下翅翼的升、阻力系数、平均升力系数、推力系数进行对比分析，获得了柔性折叠翼的最佳结构参数和运动参数。研制了仿甲虫柔性可折叠翼飞行器样机，进行了初步样机测试试验。项目研究成果为仿甲虫扑翼微型飞行器的设计提供新思路与新方法，进一步推动新型微型飞行器的研发和实际应用。