共查询到18条相似文献,搜索用时 187 毫秒
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扑翼飞行器动力系统建模方法 总被引:1,自引:0,他引:1
为快速评估扑翼飞行器的航时,便于针对不同扑动翼进行动力系统设计与优化,逐步减少实物验证与试飞,加快扑翼飞行器的研制,基于实验数据参数辨识的方法建立了包含直流无刷电机、电调(ESC)、锂电池和扑动机构等扑翼飞行器动力系统组件的动态模型,其中电机模型相对误差小于10%,锂电池动态模型相对误差小于6%;提出了一种基于风洞试验气动数据和功率数据的扑动轴瞬时气动载荷半经验高精度建模方法,解决了气动载荷测量较为困难的问题,模型确定系数大于0.89;集成以上模型后的扑翼飞行器仿真系统还包含扑动翼周期平均气动模型、平尾气动模型和纵向控制模型,确保仿真在动态配平状态下进行,可进行全任务剖面航时仿真,航时仿真与实际试飞结果相比误差小于3%。集成的扑翼飞行器仿真系统采用模块化建模思想,各模型参数独立可调,能进一步应用于扑翼飞行器多学科优化等研究。 相似文献
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微型扑翼飞行器的气动建模分析与试验 总被引:7,自引:1,他引:6
用计算流体力学的数值模拟方法研究了微扑翼飞行器的扑翼飞行的非定常空气动力学问题。在对昆虫扑翼飞行运动的仿生模拟基础上 ,对实际可飞的微扑翼飞行器的扑翼运动建立了三维翼型的运动学与空气动力学模型。利用任意拉格朗日欧拉 ( ALE)有限元方法求解出 N-S方程的数值解 ,证明简单扑翼布局所提供的升力足以克服微扑翼飞行器本身的重力使其飞行。在此基础上 ,分别计算并分析了拍动幅值、俯仰幅度以及扑翼频率等各种扑翼参数对升力的影响。最后 ,探索性的扑翼风洞试验与飞行试验结果在一定程度上验证了文中计算方法的可行性 相似文献
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仿生微扑翼飞行器机构动态分析与工程设计方法 总被引:12,自引:0,他引:12
以工程应用为背景,从全局的角度提出了一种仿生微扑翼飞行器的动态分析与设计方法。在对鸟类的飞行参数进行统计分析的基础之上,拟合出扑翼飞行的仿生学公式,并据此进行了微扑翼飞行器的仿生学初步设计。根据仿生学结果设计了飞行器的传动布局、动力方案以及总体结构,并按照运动学分析、气动力分析以及动力学分析相结合的动态分析方法研究了微扑翼飞行器的动态特性。在动态分析的基础上进行了飞行参数的优化设计,使得微扑翼飞行器达到性能最佳。样机制作及风洞试验结果证明了这种方法的有效性与可行性。所得研究结论对微扑翼飞行器的设计、制作和应用提供了一定的理论依据。 相似文献
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主动变形扑翼飞行器的设计和风洞测力试验研究 总被引:1,自引:0,他引:1
主动变形扑翼可以模仿鸟翼飞行时的复杂运动。为了了解主动变形扑翼飞行器的气动特性,在研究鸟类骨骼结构和翅膀及尾翼运动规律的基础上,设计并制造了一种基于机器人技术的主动变形扑翼飞行器;给出了主动变形扑翼飞行器的机构运动规律函数,并设计出机构运动控制系统;在低速风洞中对此飞行器进行了一系列测力试验,研究了主动变形扑翼的升力、推力特性,以及风速、扑动频率、扑动幅度、伸展相位等参数对升力和推力的影响,并与常规扑翼进行了对比分析。试验结果表明,较之常规扑翼,主动变形扑翼可以显著增加升力和增强对不同飞行状态的适应能力。 相似文献
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介绍了翼展为320mm的电动力微型飞机的一体化优化设计方法,优化设计的目标是飞机的留空时间。为求出全局最优解,选择遗传算法作为优化算子,同时采用了变复杂度的优化计算方法提高设计计算效率.然后进行了优化灵敏度分析.并根据分析结果提出了微型飞机的一般设计准则。 相似文献
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《Progress in Aerospace Sciences》1999,35(5):455-505
Micro air vehicles (MAVs) with wing spans of 15 cm or less, and flight speed of 30–60 kph are of interest for military and civilian applications. There are two prominent features of MAV flight: (i) low Reynolds number (104–105), resulting in unfavorable aerodynamic conditions to support controlled flight, and (ii) small physical dimensions, resulting in certain favorable scaling characteristics including structural strength, reduced stall speed, and low inertia. Based on observations of biological flight vehicles, it appears that wing motion and flexible airfoils are two key attributes for flight at low Reynolds number. The small size of MAVs corresponds in nature to small birds, which do not glide like large birds, but instead flap with considerable change of wing shape during a single flapping cycle. With flapping and flexible wings, birds overcome the deteriorating aerodynamic performance under steady flow conditions by employing unsteady mechanisms. In this article, we review both biological and aeronautical literatures to present salient features relevant to MAVs. We first summarize scaling laws of biological and micro air vehicles involving wing span, wing loading, vehicle mass, cruising speed, flapping frequency, and power. Next we discuss kinematics of flapping wings and aerodynamic models for analyzing lift, drag and power. Then we present issues related to low Reynolds number flows and airfoil shape selection. Recent work on flexible structures capable of adjusting the airfoil shape in response to freestream variations is also discussed. 相似文献
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Optimal thickness distributions of aeroelastic flapping shells 总被引:1,自引:0,他引:1
The severe weight limitations of flapping wing micro air vehicles necessitates the use of thin flexible wings, which in turn requires an aeroelastic modeling tool for proper numerical characterization. Furthermore, due to the unconventional nature of these vehicles, wing design guidelines for thrust and/or power considerations are not generally available; numerical design optimization then becomes a valuable tool. This work couples a nonlinear shell model to an unsteady vortex lattice solver, and then computes analytical design gradients: the derivative of aerodynamic force/power quantities with respect to a large vector of thickness variables. Gradient-based optimization is then used to locate the wing structure that maximizes the thrust, or minimizes the power under a thrust constraint, for a variety of shell boundary conditions. Changes in the topological features of the optimal wing thicknesses highlight important aeroelastic interactions that can be exploited for efficient flapping wings. 相似文献
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为了研究不同柔度的柔性翼气动特性和抗风性性能,制作了九种不同柔段的柔性翼,利用西北工业大学微型飞行器专用风洞对其进行初步的风洞试验,在实验中进行了不同风速,不同迎角对柔段的气动特性研究。通过试验优选出气动特性较好的柔段,为柔性翼微型飞行器的总体设计和气动特性提供参考。 相似文献
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通过求解雷诺平均Navier-Stokes方程,研究了同时具有扑动和俯仰运动的三维扑翼气动特性.为了模拟扑翼的弹性特性,在扑翼俯仰轴处设计了扭簧.研究了扑翼平面形状、俯仰弹性轴与质心的相对位置、俯仰刚度变化等参数的影响.结果表明:俯仰角相对扑动角有一个大的相位超前量,且刚度系数越大该超前量越大;考虑了俯仰弹性特征后,计... 相似文献
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Fixed wing micro air vehicles (wingspan between 10 and 15 cm) are aerodynamically challenging due to the low Reynolds number regime (104–105) they operate in. The low aspect ratio wings (typically used to maximize area under a size constraint) promote strong tip vortices, and are susceptible to rolling instabilities. Wind gusts can be of the same order of magnitude as the flight speed (10–15 m/s). Standard control surfaces on an empennage must be eliminated for size considerations and drag reduction, and the range of stable center of gravity locations is only a few millimeters long. Membrane aeroelasticity has been identified as a tenable method to alleviate these issues: flexible wing structures with geometric twist (adaptive washout for gust rejection, delayed stall) and aerodynamic twist (adaptive inflation for high lift, larger stability margins) are both considered here. Recent investigations in static aeroelastic characterization, including flight loads, wing deformation, flow structures, aeroelastic-tailoring studies through laminate orientation, as well as unconventional techniques based on membrane pre-tension, are reviewed. Multi-objective optimization aimed at improving lift, drag, and pitching moment considerations is also discussed. 相似文献
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